NASA Astrophysics Data System (ADS)
Pool, Thomas K.; Strecker, Angela L.; Olden, Julian D.
2013-03-01
A commonly overlooked aspect of conservation planning assessments is that wildlife managers are increasingly focused on habitats that contain non-native species. We examine this management challenge in the Gila River basin (150,730 km2), and present a new planning strategy for fish conservation. By applying a hierarchical prioritization algorithm to >850,000 fish records in 27,181 sub-watersheds we first identified high priority areas (PAs) termed "preservation PAs" with high native fish richness and low non-native richness; these represent traditional conservation targets. Second, we identified "restoration PAs" with high native fish richness that also contained high numbers of non-native species; these represent less traditional conservation targets. The top 10 % of preservation and restoration PAs contained common native species (e.g., Catostomus clarkii, desert sucker; Catostomus insignis, Sonora sucker) in addition to native species with limited distributions (i.e., Xyrauchen texanus, razorback sucker; Oncorhynchus gilae apache, Apache trout). The top preservation and restoration PAs overlapped by 42 %, indicating areas with high native fish richness range from minimally to highly invaded. Areas exclusively identified as restoration PAs also encompassed a greater percentage of native species ranges than would be expected by the random addition of an equivalent basin area. Restoration PAs identified an additional 19.0 and 26.6 % of the total ranges of two federally endangered species— Meda fulgida (spikedace) and Gila intermedia (Gila chub), respectively, compared to top preservation PAs alone—despite adding only 5.8 % of basin area. We contend that in addition to preservation PAs, restoration PAs are well suited for complementary management activities benefiting native fishes.
Pool, Thomas K; Strecker, Angela L; Olden, Julian D
2013-03-01
A commonly overlooked aspect of conservation planning assessments is that wildlife managers are increasingly focused on habitats that contain non-native species. We examine this management challenge in the Gila River basin (150,730 km(2)), and present a new planning strategy for fish conservation. By applying a hierarchical prioritization algorithm to >850,000 fish records in 27,181 sub-watersheds we first identified high priority areas (PAs) termed "preservation PAs" with high native fish richness and low non-native richness; these represent traditional conservation targets. Second, we identified "restoration PAs" with high native fish richness that also contained high numbers of non-native species; these represent less traditional conservation targets. The top 10 % of preservation and restoration PAs contained common native species (e.g., Catostomus clarkii, desert sucker; Catostomus insignis, Sonora sucker) in addition to native species with limited distributions (i.e., Xyrauchen texanus, razorback sucker; Oncorhynchus gilae apache, Apache trout). The top preservation and restoration PAs overlapped by 42 %, indicating areas with high native fish richness range from minimally to highly invaded. Areas exclusively identified as restoration PAs also encompassed a greater percentage of native species ranges than would be expected by the random addition of an equivalent basin area. Restoration PAs identified an additional 19.0 and 26.6 % of the total ranges of two federally endangered species-Meda fulgida (spikedace) and Gila intermedia (Gila chub), respectively, compared to top preservation PAs alone-despite adding only 5.8 % of basin area. We contend that in addition to preservation PAs, restoration PAs are well suited for complementary management activities benefiting native fishes.
Turek, Kelly C.; Pegg, Mark A.; Pope, Kevin L.; Schainost, Steve
2014-01-01
Non-native trout are currently stocked to support recreational fisheries in headwater streams throughout Nebraska. The influence of non-native trout introductions on native fish populations and their role in structuring fish assemblages in these systems is unknown. The objectives of this study were to determine (i) if the size structure or relative abundance of native fish differs in the presence and absence of non-native trout, (ii) if native fish-assemblage structure differs in the presence and absence of non-native trout and (iii) if native fish-assemblage structure differs across a gradient in abundances of non-native trout. Longnose dace Rhinichthys cataractae were larger in the presence of brown trout Salmo trutta and smaller in the presence of rainbow trout Oncorhynchus mykiss compared to sites without trout. There was also a greater proportion of larger white suckers Catostomus commersonii in the presence of brown trout. Creek chub Semotilus atromaculatus and fathead minnow Pimephales promelas size structures were similar in the presence and absence of trout. Relative abundances of longnose dace, white sucker, creek chub and fathead minnow were similar in the presence and absence of trout, but there was greater distinction in native fish-assemblage structure between sites with trout compared to sites without trout as trout abundances increased. These results suggest increased risk to native fish assemblages in sites with high abundances of trout. However, more research is needed to determine the role of non-native trout in structuring native fish assemblages in streams, and the mechanisms through which introduced trout may influence native fish populations.
Moyle, Peter B; Kiernan, Joseph D; Crain, Patrick K; Quiñones, Rebecca M
2013-01-01
Freshwater fishes are highly vulnerable to human-caused climate change. Because quantitative data on status and trends are unavailable for most fish species, a systematic assessment approach that incorporates expert knowledge was developed to determine status and future vulnerability to climate change of freshwater fishes in California, USA. The method uses expert knowledge, supported by literature reviews of status and biology of the fishes, to score ten metrics for both (1) current status of each species (baseline vulnerability to extinction) and (2) likely future impacts of climate change (vulnerability to extinction). Baseline and climate change vulnerability scores were derived for 121 native and 43 alien fish species. The two scores were highly correlated and were concordant among different scorers. Native species had both greater baseline and greater climate change vulnerability than did alien species. Fifty percent of California's native fish fauna was assessed as having critical or high baseline vulnerability to extinction whereas all alien species were classified as being less or least vulnerable. For vulnerability to climate change, 82% of native species were classified as highly vulnerable, compared with only 19% for aliens. Predicted climate change effects on freshwater environments will dramatically change the fish fauna of California. Most native fishes will suffer population declines and become more restricted in their distributions; some will likely be driven to extinction. Fishes requiring cold water (<22°C) are particularly likely to go extinct. In contrast, most alien fishes will thrive, with some species increasing in abundance and range. However, a few alien species will likewise be negatively affected through loss of aquatic habitats during severe droughts and physiologically stressful conditions present in most waterways during summer. Our method has high utility for predicting vulnerability to climate change of diverse fish species. It should be useful for setting conservation priorities in many different regions.
Moyle, Peter B.; Kiernan, Joseph D.; Crain, Patrick K.; Quiñones, Rebecca M.
2013-01-01
Freshwater fishes are highly vulnerable to human-caused climate change. Because quantitative data on status and trends are unavailable for most fish species, a systematic assessment approach that incorporates expert knowledge was developed to determine status and future vulnerability to climate change of freshwater fishes in California, USA. The method uses expert knowledge, supported by literature reviews of status and biology of the fishes, to score ten metrics for both (1) current status of each species (baseline vulnerability to extinction) and (2) likely future impacts of climate change (vulnerability to extinction). Baseline and climate change vulnerability scores were derived for 121 native and 43 alien fish species. The two scores were highly correlated and were concordant among different scorers. Native species had both greater baseline and greater climate change vulnerability than did alien species. Fifty percent of California’s native fish fauna was assessed as having critical or high baseline vulnerability to extinction whereas all alien species were classified as being less or least vulnerable. For vulnerability to climate change, 82% of native species were classified as highly vulnerable, compared with only 19% for aliens. Predicted climate change effects on freshwater environments will dramatically change the fish fauna of California. Most native fishes will suffer population declines and become more restricted in their distributions; some will likely be driven to extinction. Fishes requiring cold water (<22°C) are particularly likely to go extinct. In contrast, most alien fishes will thrive, with some species increasing in abundance and range. However, a few alien species will likewise be negatively affected through loss of aquatic habitats during severe droughts and physiologically stressful conditions present in most waterways during summer. Our method has high utility for predicting vulnerability to climate change of diverse fish species. It should be useful for setting conservation priorities in many different regions. PMID:23717503
Wang, Jianzhu; Chapman, Duane C.; Xu, Jun; Wang, Yang; Gu, Binhe
2018-01-01
Stable carbon and nitrogen isotope values (δ13C and δ15N) were used to evaluate trophic niche overlap between two filter-feeding fishes (known together as bigheaded carp) native to China, silver carp (Hypophthalmichthys molitrix) and bighead carp (Hypophthalmichthys nobilis), and three native filter-feeding fish including bigmouth buffalo (Ictiobus cyprinellus), gizzard shad (Dorosoma cepedianum) and paddlefish (Polyodon spathula) in the lower Missouri River, USA, using the Bayesian Stable Isotope in R statistics. Results indicate that except for bigmouth buffalo, all species displayed similar trophic niche size and trophic diversity. Bigmouth buffalo occupied a small trophic niche and had the greatest trophic overlap with silver carp (93.6%) and bighead carp (94.1%) followed by gizzard shad (91.0%). Paddlefish had a trophic niche which relied on some resources different from those used by other species, and therefore had the lowest trophic overlap with bigheaded carp and other two native fish. The trophic overlap by bigheaded carp onto native fish was typically stronger than the reverse effects from native fish. Average niche overlap between silver carp and native species was as high as 71%, greater than niche overlap between bighead carp and native fish (64%). Our findings indicate that bigheaded carps are a potential threat to a diverse and stable native fish community.
Status of native stream fishes within selected protected areas of Niobrara River in western Nebraska
Spurgeon, Jonathan J.; Stasiak, Richard H.; Cunningham, George R.; Pope, Kevin L.; Pegg, Mark A.
2014-01-01
Lotic systems within the Great Plains are characterized by highly fluctuating conditions through both space and time. Fishes inhabiting these systems have adopted specific life-history strategies to survive in such environments; however, anthropogenic disturbance to prairie streams has resulted in declines and extirpation of many native stream fishes. Terrestrial protected areas (i.e., parks and reserves) are designated to support native flora and fauna and, it is assumed, to provide protection to native fishes. We assessed the presence and relative abundance of stream fish populations within protected areas along the Niobrara River in western Nebraska based on data collected during 1979, 1989, 2008, and 2011. The spatial extent of protection, landscape changes resulting in degraded physiochemical parameters, and introduced species may reduce the effectiveness of these terrestrial protected areas in protecting native fishes in Great Plains stream environments.
Anomalous droughts, not invasion, decrease persistence of native fishes in a desert river.
Ruhí, Albert; Holmes, Elizabeth E; Rinne, John N; Sabo, John L
2015-04-01
Changing climate extremes and invasion by non-native species are two of the most prominent threats to native faunas. Predicting the relationships between global change and native faunas requires a quantitative toolkit that effectively links the timing and magnitude of extreme events to variation in species abundances. Here, we examine how discharge anomalies--unexpected floods and droughts--determine covariation in abundance of native and non-native fish species in a highly variable desert river in Arizona. We quantified stochastic variation in discharge using Fourier analyses on >15,000 daily observations. We subsequently coupled maximum annual spectral anomalies with a 15-year time series of fish abundances (1994-2008), using Multivariate Autoregressive State-Space (MARSS) models. Abiotic drivers (discharge anomalies) were paramount in determining long-term fish abundances, whereas biotic drivers (species interactions) played only a secondary role. As predicted, anomalous droughts reduced the abundances of native species, while floods increased them. However, in contrast to previous studies, we observed that the non-native assemblage was surprisingly unresponsive to extreme events. Biological trait analyses showed that functional uniqueness was higher in native than in non-native fishes. We also found that discharge anomalies influenced diversity patterns at the meta-community level, with nestedness increasing after anomalous droughts due to the differential impairment of native species. Overall, our results advance the notion that discharge variation is key in determining community trajectories in the long term, predicting the persistence of native fauna even in the face of invasion. We suggest this variation, rather than biotic interactions, may commonly underlie covariation between native and non-native faunas, especially in highly variable environments. If droughts become increasingly severe due to climate change, and floods increasingly muted due to regulation, fish assemblages in desert rivers may become taxonomically and functionally impoverished and dominated by non-native taxa. © 2014 John Wiley & Sons Ltd.
Non-native fishes in Florida freshwaters: a literature review and synthesis
Schofield, Pamela J.; Loftus, William F.
2015-01-01
Non-native fishes have been known from freshwater ecosystems of Florida since the 1950s, and dozens of species have established self-sustaining populations. Nonetheless, no synthesis of data collected on those species in Florida has been published until now. We searched the literature for peer-reviewed publications reporting original data for 42 species of non-native fishes in Florida that are currently established, were established in the past, or are sustained by human intervention. Since the 1950s, the number of non-native fish species increased steadily at a rate of roughly six new species per decade. Studies documented (in decreasing abundance): geographic location/range expansion, life- and natural-history characteristics (e.g., diet, habitat use), ecophysiology, community composition, population structure, behaviour, aquatic-plant management, and fisheries/aquaculture. Although there is a great deal of taxonomic uncertainty and confusion associated with many taxa, very few studies focused on clarifying taxonomic ambiguities of non-native fishes in the State. Most studies were descriptive; only 15 % were manipulative. Risk assessments, population-control studies and evaluations of effects of non-native fishes were rare topics for research, although they are highly valued by natural-resource managers. Though some authors equated lack of data with lack of effects, research is needed to confirm or deny conclusions. Much more is known regarding the effects of lionfish (Pterois spp.) on native fauna, despite its much shorter establishment time. Natural-resource managers need biological and ecological information to make policy decisions regarding non-native fishes. Given the near-absence of empirical data on effects of Florida non-native fishes, and the lengthy time-frames usually needed to collect such information, we provide suggestions for data collection in a manner that may be useful in the evaluation and prediction of non-native fish effects.
Geography of invasion in mountain streams: consequences of headwater lake fish introductions
Susan B. Adams; Christopher A. Frissell; Bruce E. Rieman
2001-01-01
The introduction of fish into high-elevation lakes can provide a geographic and demographic boost to their invasion of stream networks, thereby further endangering the native stream fauna. Increasingly, remaining populations of native salmonids are concentrated in fragmented headwater refugia that are protected by physical or biological barriers from introduced fishes...
NASA Astrophysics Data System (ADS)
Ruhi, A.; Olden, J. D.; Sabo, J. L.
2015-12-01
In the American Southwest, hydrologic drought has become a new normal as a result of increasing human appropriation of freshwater resources and increased aridity associated with global warming. Although drought has often been touted to threaten freshwater biodiversity, connecting drought to extinction risk of highly-imperiled faunas remains a challenge. Here we combine time-series methods from signal processing and econometrics to analyze a spatially comprehensive and long-term dataset to link discharge variation and community abundance of fish across the American Southwest. This novel time series framework identifies ongoing trends in daily discharge anomalies across the Southwest, quantifies the effect of the historical hydrologic drivers on fish community abundance, and allows us to simulate species trajectories and range-wide risk of decline (quasiextinction) under scenarios of future climate. Spectral anomalies are declining over the last 30 years in at least a quarter of the stream gaging stations across the American Southwest and these anomalies are robust predictors of historical abundance of native and non-native fishes. Quasiextinction probabilities are high (>50 %) for nearly ¾ of the native species across several large river basins in the same region; and the negative trend in annual anomalies increases quasiextinction risk for native but reduces this risk for non-native fishes. These findings suggest that ongoing drought is causing range-wide collapse and replacement of native fish faunas, and that this homogenization of western fish faunas will continue given the prevailing negative trend in discharge anomalies. Additionally, this combination of methods can be applied elsewhere as long as environmental and biological long-term time-series data are available. Collectively, these methods allow identifying the link between hydroclimatic forcing and ecological responses and thus may help anticipating the potential impacts of ongoing and future hydrologic extremes in freshwater ecosystems.
Jezorek, Ian G.; Connolly, Patrick J.; Munz, Carrie S.; Dixon, Chris
2011-01-01
Executive Summary: This project was designed to document habitat conditions and populations of native and non-native fish within the 8-kilometer Condor Canyon section of Meadow Valley Wash, Nevada, with an emphasis on Big Spring spinedace (Lepidomeda mollispinis pratensis). Other native fish present were speckled dace (Rhinichthys osculus) and desert sucker (Catostomus clarki). Big Spring spinedace were known to exist only within this drainage and were known to have been extirpated from a portion of their former habitat located downstream of Condor Canyon. Because of this extirpation and the limited distribution of Big Spring spinedace, the U.S. Fish and Wildlife Service listed this species as threatened under the Endangered Species Act in 1985. Prior to our effort, little was known about Big Spring spinedace populations or life histories and habitat associations. In 2008, personnel from the U.S. Geological Survey's Columbia River Research Laboratory began surveys of Meadow Valley Wash in Condor Canyon. Habitat surveys characterized numerous variables within 13 reaches, thermologgers were deployed at 9 locations to record water temperatures, and fish populations were surveyed at 22 individual sites. Additionally, fish were tagged with Passive Integrated Transponder (PIT) tags, which allowed movement and growth information to be collected on individual fish. The movements of tagged fish were monitored with a combination of recapture events and stationary in-stream antennas, which detected tagged fish. Meadow Valley Wash within Condor Canyon was divided by a 12-meter (m) waterfall known as Delmue Falls. About 6,100 m of stream were surveyed downstream of the falls and about 2,200 m of stream were surveyed upstream of the falls. Although about three-quarters of the surveyed stream length was downstream of Delmue Falls, the highest densities and abundance of native fish were upstream of the falls. Big Spring spinedace and desert sucker populations were highest near the upper end of Condor Canyon, where a tributary known as Kill Wash, and several springs, contribute flow and moderate high and low water temperature. Kill Wash and the area around its confluence with Meadow Valley Wash appeared important for spawning of all three native species. Detections of PIT-tagged fish indicated that there were substantial movements to this area during the spring. Our surveys included about 700 m of Meadow Valley Wash upstream of Kill Wash. A small falls about 2 m high was about 560 m upstream of Kill Wash. This falls is likely a barrier to upstream fish movement at most flows. Populations of all three native species were found upstream of this small falls. Age-0 fish of all three species were present, indicating successful spawning. The maximum upstream extent of native fish within Meadow Valley Wash was not determined. Our surveys included about 700 m of Meadow Valley Wash upstream of Kill Wash. A small falls about 2 m high was about 560 m upstream of Kill Wash. This falls is likely a barrier to upstream fish movement at most flows. Populations of all three native species were found upstream of this small falls. Age-0 fish of all three species were present, indicating successful spawning. The maximum upstream extent of native fish within Meadow Valley Wash was not determined. A population of non-native rainbow trout (Oncorhynchus mykiss) was found within the 2,000 m of stream immediately downstream of Delmue Falls. Non-native crayfish were very common both upstream and downstream of Delmue Falls. We were not able to quantify crayfish populations, but they compose a significant portion of the biomass of aquatic species in Condor Canyon. There were some distinctive habitat features that may have favored native fish upstream of Delmue Falls. Upstream of the falls, water temperatures were moderated by inputs from springs, turbidity was lower, pool habitat was more prevalent, substrate heterogeneity was higher, and there was less fine sediment than
Brown, L.R.; Michniuk, D.
2007-01-01
We analyzed monthly boat electrofishing data to characterize the littoral fish assemblages of five regions of the Sacramento-San Joaquin Delta (northern, southern, eastern, western, and central), California, during two sampling periods, 1980-1983 (1980s) and 2001-2003 (2000s), to provide information pertinent to the restoration of fish populations in this highly altered estuary. During the 1980s, almost 11,000 fish were captured, including 13 native species and 24 alien species. During the 2000s, just over 39,000 fish were captured, including 15 native species and 24 alien species. Catch per unit effort (CPUE) of total fish, alien fish, and centrarchid fish were greater in the 2000s compared with the 1980s, largely because of increased centrarchid fish CPUE. These differences in CPUE were associated with the spread of submerged aquatic vegetation (SAV), particularly an alien aquatic macrophyte Egeria densa. Native fish CPUE declined from the 1980s to the 2000s, but there was no single factor that could explain the decline. Native fish were most abundant in the northern region during both sampling periods. Nonmetric multidimensional scaling indicated similar patterns of fish assemblage composition during the two sampling periods, with the northern and western regions characterized by the presence of native species. The separation of the northern and western regions from the other regions was most distinct in the 2000s. Our results suggest that native fish restoration efforts will be most successful in the northern portion of the Delta. Management decisions on the Delta should include consideration of possible effects on SAV in littoral habitats and the associated fish assemblages and ecological processes. ?? 2007 Estuarine Research Federation.
Cooling water of power plant creates "hot spots" for tropical fishes and parasites.
Emde, Sebastian; Kochmann, Judith; Kuhn, Thomas; Dörge, Dorian D; Plath, Martin; Miesen, Friedrich W; Klimpel, Sven
2016-01-01
Thermally altered water bodies can function as "hot spots" where non-native species are establishing self-sustaining populations beyond their tropical and subtropical native regions. Whereas many tropical fish species have been found in these habitats, the introduction of non-native parasites often remains undetected. Here, n = 77 convict cichlids (Amatitlania nigrofasciata) were sampled by electro-fishing at two sites from a thermally altered stream in Germany and examined for parasite fauna and feeding ecology. Stomach content analysis suggests an opportunistic feeding strategy of A. nigrofasciata: while plant material dominated the diet at the warm water inlet (∼30 °C), relative contributions of insects, plants, and crustaceans were balanced 3 km downstream (∼27 °C). The most abundant non-native parasite species was the tropical nematode Camallanus cotti with P = 11.90 % and P = 80.00 % at the inlet and further downstream, respectively. Additionally, nematode larvae of Anguillicoloides crassus and one specimen of the subtropical species Bothriocephalus acheilognathi were isolated. A. nigrofasciata was also highly infected with the native parasite Acanthocephalus anguillae, which could be linked to high numbers of the parasite's intermediate host Asellus aquaticus. The aim of this study was to highlight the risk and consequences of the release and establishment of ornamental fish species for the introduction and spread of non-indigenous metazoan parasites using the convict cichlid as a model species. Furthermore, the spread of non-native parasites into adjacent fish communities needs to be addressed in the future as first evidence of Camallanus cotti in native fish species was also found.
Ward, David L.; O'neill, Matthew W.; Ka'apu-Lyons, Cassie
2015-01-01
Electrofishing is commonly used when renovating small streams to remove nuisance fishes but the likelihood of complete eradication of unwanted species, particularly warm-water fishes, is unknown. In October of 2008, we electrofished Bonita Creek, a small stream with base flows (<0.56 m3/s) in southern Arizona, and then treated the stream with rotenone to kill all of the remaining fish and quantify the effectiveness of single and multiple-pass electro fishing. Six, 100-m transects were electro fished on three consecutive days followed by a single treatment with rotenone. Fish caught using electrofishing were identified, counted and removed from each transect daily and then compared to numbers of dead fish collected during the subsequent rotenone application. Electrofishing effectiveness was highly variable among transects. Single-pass electrofishing caught an average of 23% (95% CI=5 to 40%) of the fish present, and three-pass electrofishing on consecutive days caught on average 55% (95% CI=28 to 83%) of the fish in each transect. Native Arizona fishes were more susceptible to electrofishing (77 % captured) than non-native species (54% captured), though native fish were rare. Transects in Bonita Creek averaged 3.6±1.5 m wide and 0.25±0.20 m deep (max depth 1.2 m). Bonita Creek is a small first-order stream which exhibits ideal conditions for backpack electrofishing, yet we captured a relatively small percentage of the fish present. This suggests that complete removal of non-native warm-water fishes using backpack electrofishing is not likely to be successful, especially in larger more complex streams.
Habitat restoration as a means of controlling non-native fish in a Mojave desert Oasis
Scoppettone, G.G.; Rissler, P.H.; Gourley, C.; Martinez, C.
2005-01-01
Non-native fish generally cause native fish decline, and once non-natives are established, control or elimination is usually problematic. Because non-native fish colonization has been greatest in anthropogenically altered habitats, restoring habitat similar to predisturbance conditions may offer a viable means of non-native fish control. In this investigation we identified habitats favoring native over non-native fish in a Mojave Desert oasis (Ash Meadows) and used this information to restore one of its major warm water spring systems (Kings Pool Spring). Prior to restoration, native fishes predominated in warm water (25-32??C) stream and spring-pool habitat, whereas non-natives predominated in cool water (???23??C) spring-pool and marsh/slack water habitat. Native Amargosa pupfish (Cyprinodon nevadensis) and Ash Meadows speckled dace (Rhinichthys osculus nevadensis) inhabited significantly faster mean water column velocities (MWCV) and greater total depth (TD) than non-native Sailfin molly (Poecilia latipinna) and Mosquitofish (Gambusia affinis) in warm water stream habitat, and Ash Meadows speckled dace inhabited significantly faster water than non-natives in cool water stream habitat. Modification of the outflow of Kings Pool Spring from marsh to warm water stream, with MWCV, TD, and temperature favoring native fish, changed the fish composition from predominantly non-native Sailfin molly and Mosquitofish to predominantly Ash Meadows pupfish. This result supports the hypothesis that restoring spring systems to a semblance of predisturbance conditions would promote recolonization of native fishes and deter non-native fish invasion and proliferation. ?? 2005 Society for Ecological Restoration International.
An Ecosystem-Service Approach to Evaluate the Role of Non-Native Species in Urbanized Wetlands
Yam, Rita S. W.; Huang, Ko-Pu; Hsieh, Hwey-Lian; Lin, Hsing-Juh; Huang, Shou-Chung
2015-01-01
Natural wetlands have been increasingly transformed into urbanized ecosystems commonly colonized by stress-tolerant non-native species. Although non-native species present numerous threats to natural ecosystems, some could provide important benefits to urbanized ecosystems. This study investigated the extent of colonization by non-native fish and bird species of three urbanized wetlands in subtropical Taiwan. Using literature data the role of each non-native species in the urbanized wetland was evaluated by their effect (benefits/damages) on ecosystem services (ES) based on their ecological traits. Our sites were seriously colonized by non-native fishes (39%–100%), but <3% by non-native birds. Although most non-native species could damage ES regulation (disease control and wastewater purification), some could be beneficial to the urbanized wetland ES. Our results indicated the importance of non-native fishes in supporting ES by serving as food source to fish-eating waterbirds (native, and migratory species) due to their high abundance, particularly for Oreochromis spp. However, all non-native birds are regarded as “harmful” species causing important ecosystem disservices, and thus eradication of these bird-invaders from urban wetlands would be needed. This simple framework for role evaluation of non-native species represents a holistic and transferable approach to facilitate decision making on management priority of non-native species in urbanized wetlands. PMID:25860870
Environmental drivers of fish functional diversity and composition in the Lower Colorado River Basin
Pool, T.K.; Olden, J.D.; Whittier, Joanna B.; Paukert, C.P.
2010-01-01
Freshwater conservation efforts require an understanding of how natural and anthropogenic factors shape the present-day biogeography of native and non-native species. This knowledge need is especially acute for imperiled native fishes in the highly modified Lower Colorado River Basin (LCRB), USA. In the present study we employed both a taxonomic and functional approach to explore how natural and human-related environmental drivers shape landscape-scale patterns of fish community composition in the LCRB. Our results showed that hydrologic alteration, watershed land use, and regional climate explained 30.3% and 44.7% of the total variation in fish community taxonomic and functional composition, respectively. Watersheds with greater dam densities and upstream storage capacity supported higher non-native functional diversity, suggesting that dams have provided additional "niche opportunities" for non-native equilibrium life-history strategists by introducing new reservoir habitat and modifying downstream flow and thermal regimes. By contrast, watersheds characterized by greater upstream land protection, lower dam densities, and higher variation in spring and summer precipitation supported fish communities with a strong complement of native species (opportunistic-periodic strategists). In conclusion, our study highlights the utility of a life-history approach to better understand the patterns and processes by which fish communities vary along environmental gradients.
Invasive lionfish harbor a different external bacterial community than native Bahamian fishes
NASA Astrophysics Data System (ADS)
Stevens, J. L.; Olson, J. B.
2013-12-01
The introduction and subsequent spread of lionfish into the Atlantic Ocean and Caribbean Sea has become a worldwide conservation issue. These highly successful invaders may also be capable of introducing non-native microorganisms to the invaded regions. This study compared the bacterial communities associated with lionfish external tissue to those of native Bahamian fishes and ambient water. Terminal restriction fragment length polymorphism analyses demonstrated that lionfish bacterial communities were significantly different than those associated with three native Bahamian fishes. Additionally, all fishes harbored distinct bacterial communities from the ambient bacterioplankton. Analysis of bacterial clone libraries from invasive lionfish and native squirrelfish indicated that lionfish communities were more diverse than those associated with squirrelfish, yet did not contain known fish pathogens. Using microscopy and molecular genetic approaches, lionfish eggs were examined for the presence of bacteria to evaluate the capacity for vertical transmission. Eggs removed from the ovaries of gravid females were free of bacteria, suggesting that lionfish likely acquire bacteria from the environment. This study was the first examination of bacterial communities associated with the invasive lionfish and indicated that they support different communities of environmentally derived bacteria than Caribbean reef fishes.
Early detection of non-native fishes using fish larvae
Our objective was to evaluate the use of fish larvae for early detection of non-native fishes, comparing traditional and molecular taxonomy approaches to investigate potential efficiencies. Fish larvae present an interesting opportunity for non-native fish early detection. First,...
DNA metabarcoding of fish larvae for detection of non-native fishes
Our objective was to evaluate the use of fish larvae for early detection of non-native fishes, comparing traditional and molecular taxonomy approaches to investigate potential efficiencies. Fish larvae present an interesting opportunity for non-native fish early detection because...
Warren, Melvin L.; Burr, Brooks M.; Walsh, Stephen J.; Bart, Henry L.; Cashner, Robert C.; Etnier, David A.; Freeman, Byron J.; Kuhajda, Bernard R.; Mayden, Richard L.; Robison, Henry W.; Ross, Stephen T.; Starnes, Wayne C.
2000-01-01
The Southeastern Fishes Council Technical Advisory Committee reviewed the diversity, distribution, and status of all native freshwater and diadromous fishes across 51 major drainage units of the southern United States. The southern United States supports more native fishes than any area of comparable size on the North American continent north of Mexico, but also has a high proportion of its fishes in need of conservation action. The review included 662 native freshwater and diadromous fishes and 24 marine fishes that are significant components of freshwater ecosystems. Of this total, 560 described, freshwater fish species are documented, and 49 undescribed species are included provisionally pending formal description. Described subspecies (86) are recognized within 43 species, 6 fishes have undescribed subspecies, and 9 others are recognized as complexes of undescribed taxa. Extinct, endangered, threatened, or vulnerable status is recognized for 28% (187 taxa) of southern freshwater and diadromous fishes. To date, 3 southern fishes are known to be extinct throughout their ranges, 2 are extirpated from the study region, and 2 others may be extinct. Of the extant southern fishes, 41 (6%) are regarded as endangered, 46 (7%) are regarded as threatened, and 101 (15%) are regarded as vulnerable. Five marine fishes that frequent fresh water are regarded as vulnerable. Our assessment represents a 75% increase in jeopardized southern fishes since 1989 and a 125% increase in 20 years. The trend for fishes in the southern United States is clear; jeopardized fishes are successively being moved from the vulnerable category to that of imminent threat of extinction.
Species richness and patterns of invasion in plants, birds, and fishes in the United States
Stohlgren, Thomas J.; Barnett, David; Flather, Curtis; Fuller, Pamela L.; Peterjohn, Bruce G.; Kartesz, John; Master, Lawrence L.
2006-01-01
We quantified broad-scale patterns of species richness and species density (mean # species/km2) for native and non-indigenous plants, birds, and fishes in the continental USA and Hawaii. We hypothesized that the species density of native and non-indigenous taxa would generally decrease in northern latitudes and higher elevations following declines in potential evapotranspiration, mean temperature, and precipitation. County data on plants (n = 3004 counties) and birds (n=3074 counties), and drainage (6 HUC) data on fishes (n = 328 drainages) showed that the densities of native and non-indigenous species were strongly positively correlated for plant species (r = 0.86, P < 0.0001), bird species (r = 0.93, P<0.0001), and fish species (r = 0.41, P<0.0001). Multiple regression models showed that the densities of native plant and bird species could be strongly predicted (adj. R2 = 0.66 in both models) at county levels, but fish species densities were less predictable at drainage levels (adj. R2 = 0.31,P<0.0001). Similarly, non-indigenous plant and bird species densities were strongly predictable (adj. R2 = 0.84 and 0.91 respectively), but non-indigenous fish species density was less predictable (adj. R2 = 0.38). County level hotspots of native and non-indigenous plants, birds, and fishes were located in low elevation areas close to the coast with high precipitation and productivity (vegetation carbon). We show that (1) native species richness can be moderately well predicted with abiotic factors; (2) human populations have tended to settle in areas rich in native species; and (3) the richness and density of non-indigenous plant, bird, and fish species can be accurately predicted from biotic and abiotic factors largely because they are positively correlated to native species densities. We conclude that while humans facilitate the initial establishment, invasions of non-indigenous species, the spread and subsequent distributions of non-indigenous species may be controlled largely by environmental factors.
Protocol for Monitoring Fish Assemblages in Pacific Northwest National Parks
Brenkman, Samuel J.; Connolly, Patrick J.
2008-01-01
Rivers and streams that drain from Olympic, Mount Rainier, and North Cascades National Parks are among the most protected corridors in the lower 48 States, and represent some of the largest tracts of contiguous, undisturbed habitat throughout the range of several key fish species of the Pacific Northwest. These watersheds are of high regional importance as freshwater habitat sanctuaries for native fish, where habitat conditions are characterized as having little to no disturbance from development, channelization, impervious surfaces, roads, diversions, or hydroelectric projects. Fishery resources are of high ecological and cultural importance in Pacific Northwest National Parks, and significantly contribute to economically important recreational, commercial, and tribal fisheries. This protocol describes procedures to monitor trends in fish assemblages, fish abundance, and water temperature in eight rivers and five wadeable streams in Olympic National Park during summer months, and is based on 4 years of field testing. Fish assemblages link freshwater, marine, and terrestrial ecosystems. They also serve as focal resources of national parks and are excellent indicators of ecological conditions of rivers and streams. Despite the vital importance of native anadromous and resident fish populations, there is no existing monitoring program for fish assemblages in the North Coast and Cascades Network. Specific monitoring objectives of this protocol are to determine seasonal and annual trends in: (1) fish species composition, (2) timing of migration of adult fish, (3) relative abundance, (4) age and size structure, (5) extent of non-native and hatchery fish, and (6) water temperature. To detect seasonal and annual trends in fish assemblages in reference sites, we rely on repeated and consistent annual sampling at each monitoring site. The general rationale for the repeated sampling of reference sites is to ensure that we account for the high interannual variability in fish movements and abundances in rivers. One underlying assumption is that the monitoring program is designed in perpetuity, and consequently our capability to detect trends substantially increases with time. The protocol describes sampling designs, methods, training procedures, safety considerations, data management, data analysis, and reporting. The allocation of sampling effort represents a balance between ecological considerations, a sound monitoring approach, and practical limitations caused by logistical constraints and a limited annual budget of $55,000. The widespread declines of native fish species in western North America highlights the importance and urgency of understanding trends in fish assemblages from undisturbed habitats. Seasonal and annual trends in fish assemblages will provide insights at the individual, population, and assemblage level. This protocol will allow managers to detect increases and decreases in abundance of priority management species, and occurrence of non-native, hatchery, and federally listed fish. The detection of trends in fish assemblages will allow for specific management actions that may include: implementation of more appropriate fishing regulations, evaluation of existing hatchery releases, control of non-native fish species, and prioritization of habitat restoration projects. Dissemination and communication of scientific findings on North Coast and Cascades Network fish assemblages will be a core product of this protocol, which will have much relevance to decision makers, park visitors, researchers, and educators.
Coggins,, Lewis G.; Yard, Michael D.; Pine, William E.
2011-01-01
The federally endangered humpback chub Gila cypha in the Colorado River within Grand Canyon is currently the focus of a multiyear program of ecosystem-level experimentation designed to improve native fish survival and promote population recovery as part of the Glen Canyon Dam Adaptive Management Program. A key element of this experiment was a 4-year effort to remove nonnative fishes from critical humpback chub habitat, thereby reducing potentially negative interactions between native and nonnative fishes. Over 36,500 fish from 15 species were captured in the mechanical removal reach during 2003–2006. The majority (64%) of the catch consisted of nonnative fish, including rainbow trout Oncorhynchus mykiss (19,020), fathead minnow Pimephales promelas (2,569), common carp Cyprinus carpio (802), and brown trout Salmo trutta (479). Native fish (13,268) constituted 36% of the total catch and included flannelmouth suckers Catostomus latipinnis (7,347), humpback chub (2,606), bluehead suckers Catostomus discobolus (2,243), and speckled dace Rhinichthys osculus (1,072). The contribution of rainbow trout to the overall species composition fell steadily throughout the study period from a high of approximately 90% in January 2003 to less than 10% in August 2006. Overall, the catch of nonnative fish exceeded 95% in January 2003 and fell to less than 50% after July 2005. Our results suggest that removal efforts were successful in rapidly shifting the fish community from one dominated numerically by nonnative species to one dominated by native species. Additionally, increases in juvenile native fish abundance within the removal reach suggest that removal efforts may have promoted greater survival and recruitment. However, drought-induced increases in river water temperature and a systemwide decrease in rainbow trout abundance concurrent with our experiment made it difficult to determine the cause of the apparent increase in juvenile native fish survival and recruitment. Experimental efforts continue and may be able to distinguish among these factors and to better inform future management actions.
Native Fish Sanctuary Project - Sanctuary Development Phase, 2007 Annual Report
Mueller, Gordon A.
2007-01-01
Notable progress was made in 2007 toward the development of native fish facilities in the Lower Colorado River Basin. More than a dozen facilities are, or soon will be, online to benefit native fish. When this study began in 2005 no self-supporting communities of either bonytail or razorback sucker existed. Razorback suckers were removed from Rock Tank in 1997 and the communities at High Levee Pond had been compromised by largemouth bass in 2004. This project reversed that trend with the establishment of the Davis Cove native fish community in 2005. Bonytail and razorback sucker successfully produced young in Davis Cove in 2006. Bonytail successfully produced young in Parker Dam Pond in 2007, representing the first successful sanctuary established solely for bonytail. This past year, Three Fingers Lake received 135 large razorback suckers, and Federal and State agencies have agreed to develop a cooperative management approach dedicating a portion of that lake toward grow-out and (or) the establishment of another sanctuary. Two ponds at River's Edge Golf Course in Needles, California, were renovated in June and soon will be stocked with bonytail. Similar activities are taking place at Mohave Community College, Cerbat Cliffs Golf Course, Cibola High Levee Pond, Office Cove, Emerald Canyon Golf Course, and Bulkhead Cove. Recruitment can be expected as fish become sexually mature at these facilities. Flood-plain facilities have the potential to support 6,000 adult razorback suckers and nearly 20,000 bonytail if native fish management is aggressively pursued. This sanctuary project has assisted agencies in developing 15 native fish communities by identifying specific resource objectives for those sites, listing and prioritizing research opportunities and needs, and strategizing on management approaches through the use of resource-management plans. Such documents have been developed for Davis Cove, Cibola High Levee Pond, Parker Dam Pond, and Three Fingers Lake. We anticipate similar documents will be developed in the near future for River's Edge Golf Course Ponds, Office Cove, Emerald Canyon Golf Course Ponds, Bulkhead Cove, Mohave Community College, and Cerbat Cliffs Golf Course ponds as these facilities come on line or are developed in the future. The following report discusses the process that went into the development of these facilities. Sites were visited, assessed as to their suitability based on the control of nonnative predators, habitat suitability, conversion cost, logistics, geographical location, and willingness of landowners. They were then prioritized according to their suitability, cost, timely conversion, and willingness of landowners. Existing native fish facilities were included in this evaluation for their value in helping to determine physical and biological parameter ranges. This report describes the approaches that led to success, those leading to failure, and some of the biological, institutional, and management issues of implementing native fish sanctuary development.
Ward, David L.; Morton-Starner, Rylan
2015-01-01
Predation on juvenile native fish by introduced Rainbow Trout and Brown Trout is considered a significant threat to the persistence of endangered Humpback Chub Gila cypha in the Colorado River in the Grand Canyon. Diet studies of Rainbow Trout and Brown Trout in Glen and Grand canyons indicate that these species do eat native fish, but impacts are difficult to assess because predation vulnerability is highly variable, depending on prey size, predator size, and the water temperatures under which the predation interactions take place. We conducted laboratory experiments to evaluate how short-term predation vulnerability of juvenile native fish changes in response to fish size and water temperature using captivity-reared Humpback Chub, Bonytail, and Roundtail Chub. Juvenile chub 45–90 mm total length (TL) were exposed to adult Rainbow and Brown trouts at 10, 15, and 20°C to measure predation vulnerability as a function of water temperature and fish size. A 1°C increase in water temperature decreased short-term predation vulnerability of Humpback Chub to Rainbow Trout by about 5%, although the relationship is not linear. Brown Trout were highly piscivorous in the laboratory at any size > 220 mm TL and at all water temperatures we tested. Understanding the effects of predation by trout on endangered Humpback Chub is critical in evaluating management options aimed at preserving native fishes in Grand Canyon National Park.
Weaver, D.; Kwak, Thomas J.
2013-01-01
Fisheries managers are faced with the challenge of balancing the management of recreational fisheries with that of conserving native species and preserving ecological integrity. The negative effects that nonnative trout species exert on native trout are well documented and include alteration of competitive interactions, habitat use, and production. However, the effects that nonnative trout may exert on nongame fish assemblages are poorly understood. Our objectives were to quantify the effects of trout stocking on native nongame fish assemblages intensively on one newly stocked river, the North Toe River, North Carolina, and extensively on other southern Appalachian Mountain streams that are annually stocked with trout. In the intensive study, we adopted a before-after, control-impact (BACI) experimental design to detect short-term effects on the nongame fish assemblage and found no significant differences in fish density, species richness, species diversity, or fish microhabitat use associated with trout stocking. We observed differences in fish microhabitat use between years, however, which suggests there is a response to environmental changes, such as the flow regime, which influence available habitat. In the extensive study, we sampled paired stocked and unstocked stream reaches to detect long-term effects from trout stocking; however, we detected no differences in nongame fish density, species richness, species diversity, or population size structure between paired sites. Our results revealed high inherent system variation caused by natural and anthropogenic factors that appear to overwhelm any acute or chronic effect of stocked trout. Furthermore, hatchery-reared trout may be poor competitors in a natural setting and exert a minimal or undetectable impact on native fish assemblages in these streams. These findings provide quantitative results necessary to assist agencies in strategic planning and decision making associated with trout fisheries, stream management, and conservation of native fishes.
Native fish sanctuaries of the lower Colorado River: Cibola High Levee Pond, Desert Pupfish Pond
Mueller, G.
2005-01-01
Isolated by high mountains and harsh deserts, its fish community developed unique and specialized traits that helped them survive raging floods and prolonged droughts. Conditions were so unique that three quarters of the fish species are found nowhere else in the world?|
Spatial extent and dynamics of dam impacts on tropical island freshwater fish assemblages
Cooney, Patrick B.; Kwak, Thomas J.
2013-01-01
Habitat connectivity is vital to the persistence of migratory fishes. Native tropical island stream fish assemblages composed of diadromous species require intact corridors between ocean and riverine habitats. High dams block fish migration, but low-head artificial barriers are more widespread and are rarely assessed for impacts. Among all 46 drainages in Puerto Rico, we identified and surveyed 335 artificial barriers that hinder fish migration to 74.5% of the upstream habitat. We also surveyed occupancy of native diadromous fishes (Anguillidae, Eleotridae, Gobiidae, and Mugilidae) in 118 river reaches. Occupancy models demonstrated that barriers 2 meters (m) high restricted nongoby fish migration and extirpated those fish upstream of 4-m barriers. Gobies are adapted to climbing and are restricted by 12-m barriers and extirpated upstream of 32-m barriers. Our findings quantitatively illustrate the extensive impact of low-head structures on island stream fauna and provide guidance for natural resource management, habitat restoration, and water development strategies.
Colin, Nicole; Villéger, Sébastien; Wilkes, Martin; de Sostoa, Adolfo; Maceda-Veiga, Alberto
2018-06-01
Trait-based ecology has been developed for decades to infer ecosystem responses to stressors based on the functional structure of communities, yet its value in species-poor systems is largely unknown. Here, we used an extensive dataset in a Spanish region highly prone to non-native fish invasions (15 catchments, N=389 sites) to assess for the first time how species-poor communities respond to large-scale environmental gradients using a taxonomic and functional trait-based approach in riverine fish. We examined total species richness and three functional trait-based indices available when many sites have ≤3 species (specialization, FSpe; originality, FOri and entropy, FEnt). We assessed the responses of these taxonomic and functional indices along gradients of altitude, water pollution, physical habitat degradation and non-native fish biomass. Whilst species richness was relatively sensitive to spatial effects, functional diversity indices were responsive across natural and anthropogenic gradients. All four diversity measures declined with altitude but this decline was modulated by physical habitat degradation (richness, FSpe and FEnt) and the non-native:total fish biomass ratio (FSpe and FOri) in ways that varied between indices. Furthermore, FSpe and FOri were significantly correlated with Total Nitrogen. Non-native fish were a major component of the taxonomic and functional structure of fish communities, raising concerns about potential misdiagnosis between invaded and environmentally-degraded river reaches. Such misdiagnosis was evident in a regional fish index widely used in official monitoring programs. We recommend the application of FSpe and FOri to extensive datasets from monitoring programs in order to generate valuable cross-system information about the impacts of non-native species and habitat degradation, even in species-poor systems. Scoring non-native species apart from habitat degradation in the indices used to determine ecosystem health is essential to develop better management strategies. Copyright © 2018 Elsevier B.V. All rights reserved.
Mercury and selenium in the food web of Lake Nahuel Huapi, Patagonia, Argentina.
Arcagni, Marina; Rizzo, Andrea; Juncos, Romina; Pavlin, Majda; Campbell, Linda M; Arribére, María A; Horvat, Milena; Ribeiro Guevara, Sergio
2017-01-01
Despite located far from point sources of Hg pollution, high concentrations were recorded in plankton from the deep oligotrophic Lake Nahuel Huapi, located in North Patagonia. Native and introduced top predator fish with differing feeding habits are a valuable economic resource to the region. Hence, Hg and Se trophic interactions and pathways to these fish were assessed in the food web of this lake at three sites, using stable nitrogen and carbon isotopes. As expected based on the high THg in plankton, mercury did not biomagnify in the food web of Lake Nahuel Huapi, as most of the THg in plankton is in the inorganic form. As was observed in other aquatic systems, Se did not biomagnify either. When trophic pathways to top predator fish were analyzed, they showed that THg biomagnified in the food chains of native fish but biodiluted in the food chains of introduced salmonids. A more benthic diet, typical of native fish, resulted in higher [THg] bioaccumulation than a more pelagic or mixed diet, as in the case of introduced fish. Se:THg molar ratios were higher than 1 in all the fish species, indicating that Se might be offering a natural protection against Hg toxicity. Copyright © 2016 Elsevier Ltd. All rights reserved.
Seegert, Sarah E. Zahn; Rosi-Marshall, Emma J.; Baxter, Colden V.; Kennedy, Theodore A.; Hall, Robert O.; Cross, Wyatt F.
2014-01-01
River regulation may mediate the interactions among native and nonnative species, potentially favoring nonnative species and contributing to the decline of native populations. We examined food resource use and diet overlap among small-bodied fishes in the Grand Canyon section of the Colorado River as a first step in evaluating potential resource competition. We compared the diets of the predominant small-bodied fishes (native Speckled Dace Rhinichthys osculus, juvenile Flannelmouth Sucker Catostomus latipinnis, and juvenile Bluehead Sucker C. discobolus, and nonnative Fathead Minnow Pimephales promelas) across seasons at four sites downstream of Glen Canyon Dam using nonmetric multidimensional scaling and Schoener's similarity index. The diets of these fishes included diatoms, amorphous detritus, aquatic invertebrates (especially simuliid and chironomid larvae), terrestrial invertebrates, and terrestrial vegetation. Diets varied with season and were affected by high turbidity. Fish consumed more amorphous detritus and terrestrial vegetation during the summer monsoon season (July–September), when turbidity was higher. The diets of all species overlapped, but there was large variation in the degree of overlap. The diets of juvenile suckers and Fathead Minnows were most similar, while Speckled Dace had relatively distinct diets. The differences took the form of higher proportions of diatoms and amorphous detritus in the diets of Bluehead Suckers and Fathead Minnows and higher proportions of simuliids and chironomids in those of Speckled Dace. If food resources are or become limiting, diet overlap suggests that competition may occur among native and nonnative species, which could have implications for the population dynamics of these fishes and for the management of the Colorado River ecosystem in Grand Canyon.
Wang, Kai; Zhang, Shou-Yu; Wang, Zhen-Hua; Zhao, Jing; Xu, Min; Lin, Jun
2012-02-01
Based on the monthly investigation data of fish resources in the rocky reef habitat off Gouqi Island from March 2009 to February 2010, this paper studied the dietary composition of three native fish species (Sebasticus marmoratus, Hexagrammos otakii and Hexagrammos agrammus) and three non-native fish species (Lateolabrax japonica, Nibea albiflora and Larimichthys polyactis). The analysis of gut content indicated that the main prey items of these six dominant fish species were Caprellidae, Gammaridea, juvenile S. marmoratus, Engraulis japonicas and Acetes chinensis and the dietary composition of each of the 6 fish species had obvious seasonal variation. There was an intense food competition between native species H. otakii and H. agrammus in autumn, between non-native species N. albiflora and L. polyactis in summer, between non-native species N. albiflora and native species S. marmoratus in autumn, and between non-native species N. albiflora and native species H. otakii in winter. It was suggested the non-native species N. albiflora was the key species in the food competition among the six dominant fish species in this rocky reef habitat, and thus the feeding behaviors of these six fish species could have definite effects on the resource capacity of juvenile S. marmoratus.
Behaviors of southwestern native fishes in response to introduced catfish predators
Ward, David L.; Figiel, Chester R.
2013-01-01
Native fishes reared in hatcheries typically suffer high predation mortality when stocked into natural environments. We evaluated the behavior of juvenile bonytail Gila elegans, roundtail chub Gila robusta, razorback sucker Xyrauchen texanus, and Sonora sucker Catostomus insignis in response to introduced channel catfish Ictalurus punctatus and flathead catfish Pylodictis olivaris. Our laboratory tests indicate these species did not inherently recognize catfish as a threat, but they can quickly (within 12 h) change their behavior in response to a novel predator paired with the sight and scent of a dead conspecific. Chubs appear to avoid predation by swimming away from the threat, whereas suckers reduced movement. Effects of antipredator conditioning on survival of fish reared in hatcheries is unknown; however, our results suggest some native fish can be conditioned to recognize introduced predators, which could increase poststocking survival.
Natural flow regimes, nonnative fishes, and native fish persistence in arid-land river systems.
Propst, David L; Gido, Keith B; Stefferud, Jerome A
2008-07-01
Escalating demands for water have led to substantial modifications of river systems in arid regions, which coupled with the widespread invasion of nonnative organisms, have increased the vulnerability of native aquatic species to extirpation. Whereas a number of studies have evaluated the role of modified flow regimes and nonnative species on native aquatic assemblages, few have been conducted where the compounding effects of modified flow regimes and established nonnatives do not confound interpretations, particularly at spatial and temporal scales that are relevant to conservation of species at a range-wide level. By evaluating a 19-year data set across six sites in the relatively unaltered upper Gila River basin, New Mexico, USA, we tested how natural flow regimes and presence of nonnative species affected long-term stability of native fish assemblages. Overall, we found that native fish density was greatest during a wet period at the beginning of our study and declined during a dry period near the end of the study. Nonnative fishes, particularly predators, generally responded in opposite directions to these climatic cycles. Our data suggested that chronic presence of nonnative fishes, coupled with naturally low flows reduced abundance of individual species and compromised persistence of native fish assemblages. We also found that a natural flow regime alone was unlikely to ensure persistence of native fish assemblages. Rather, active management that maintains natural flow regimes while concurrently suppressing or excluding nonnative fishes from remaining native fish strongholds is critical to conservation of native fish assemblages in a system, such as the upper Gila River drainage, with comparatively little anthropogenic modification.
Patterns and drivers of fish extirpations in rivers of the American Southwest and Southeast.
Kominoski, John S; Ruhí, Albert; Hagler, Megan M; Petersen, Kelly; Sabo, John L; Sinha, Tushar; Sankarasubramanian, Arumugam; Olden, Julian D
2018-03-01
Effective conservation of freshwater biodiversity requires spatially explicit investigations of how dams and hydroclimatic alterations among climate regions may interact to drive species to extinction. We investigated how dams and hydroclimatic alterations interact with species ecological and life history traits to influence past extirpation probabilities of native freshwater fishes in the Upper and Lower Colorado River (CR), Alabama-Coosa-Tallapoosa (ACT), and Apalachicola-Chattahoochee-Flint (ACF) basins. Using long-term discharge data for continuously gaged streams and rivers, we quantified streamflow anomalies (i.e., departure "expected" streamflow) at the sub-basin scale over the past half-century. Next, we related extirpation probabilities of native fishes in both regions to streamflow anomalies, river basin characteristics, species traits, and non-native species richness using binomial logistic regression. Sub-basin extirpations in the Southwest (n = 95 Upper CR, n = 130 Lower CR) were highest in lowland mainstem rivers impacted by large dams and in desert springs. Dampened flow seasonality, increased longevity (i.e., delayed reproduction), and decreased fish egg sizes (i.e., lower parental care) were related to elevated fish extirpation probability in the Southwest. Sub-basin extirpations in the Southeast (ACT n = 46, ACF n = 22) were most prevalent in upland rivers, with flow dependency, greater age and length at maturity, isolation by dams, and greater distance upstream. Our results confirm that dams are an overriding driver of native fish species losses, irrespective of basin-wide differences in native or non-native species richness. Dams and hydrologic alterations interact with species traits to influence community disassembly, and very high extirpation risks in the Southeast are due to interactions between high dam density and species restricted ranges. Given global surges in dam building and retrofitting, increased extirpation risks should be expected unless management strategies that balance flow regulation with ecological outcomes are widely implemented. © 2017 John Wiley & Sons Ltd.
Modeling the response of native steelhead to hatchery supplementation programs in an Idaho River
Byrne, Alan; Bjornn, T.C.; McIntyre, J.D.
1993-01-01
A life history model was used to predict the response of native steelhead Oncorhynchus mykiss in the Lochsa River, Idaho, to long-term supplementation with hatchery fry and smolts. The four key factors affecting the response of the native fish to a stocking program were (1) the number of native spawners, (2) the number of stocked fish, (3) the number and fitness of progeny from stocked fish, and (4) the amount of mating between hatchery and native fish. Long-term stocking of fry or smolts led to the extinction of native fish in some scenarios. The model can be used to help assess the risks and benefits of proposed stocking programs.
Cutting, Kyle A.; Cross, Wyatt F.; Anderson, Michelle L.; Reese, Elizabeth G.
2016-01-01
Introduction of non-native species is a leading threat to global aquatic biodiversity. Competition between native and non-native species is often influenced by changes in suitable habitat or food availability. We investigated diet breadth and degree of trophic niche overlap for a fish assemblage of native and non-native species inhabiting a shallow, high elevation lake system. This assemblage includes one of the last remaining post-glacial endemic populations of adfluvial Arctic grayling (Thymallus arcticus) in the contiguous United States. We examined gut contents and stable isotope values of fish taxa in fall and spring to assess both short- (days) and long-term (few months) changes in trophic niches. We incorporate these short-term (gut contents) data into a secondary isotope analysis using a Bayesian statistical framework to estimate long-term trophic niche. Our data suggest that in this system, Arctic grayling share both a short- and long-term common food base with non-native trout of cutthroat x rainbow hybrid species (Oncorhynchus clarkia bouvieri x Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis). In addition, trophic niche overlap among Arctic grayling, hybrid trout, and brook trout appeared to be stronger during spring than fall. In contrast, the native species of Arctic grayling, burbot (Lota lota), and suckers (Catostomus spp.) largely consumed different prey items. Our results suggest strong seasonal differences in trophic niche overlap among Arctic grayling and non-native trout, with a potential for greatest competition for food during spring. We suggest that conservation of endemic Arctic grayling in high-elevation lakes will require recognition of the potential for coexisting non-native taxa to impede well-intentioned recovery efforts. PMID:27205901
Effects of introduced crayfish on selected native fishes of Arizona
Carpenter, J.
2000-01-01
The virile crayfish (Orconectes virilis), an aggressive polytrophic species, has been introduced into many Arizona streams. I investigated competition and predation between this crayfish and several native Arizona fishes. I conducted field experiments to assess competition for food between crayfish and fish, and laboratory experiments to examine competition for shelter and food, and predation. In Sabino Creek, I manipulated crayfish densities in isolated pools to examine effects of crayfish on growth, mortality, and recruitment of Gila chub (Gila intermedia). Regardless of crayfish density, Gila chub declined slightly in weight and condition. Mortality and recruitment did not differ between densities of crayfish. I examined crayfish effects on benthic macroinvertebrates, a submerged aquatic macrophyte and associated invertebrates, and three fish species in a small stream in the White Mountains by fencing eight stream sections to prevent movement. The three fishes were speckled dace (Rhinichthys osculus), Sonora sucker (Catostomus insignis), and desert sucker (C. clarki). Molluscs > 10 mm and macrophytes were less abundant at sites with a high density of crayfish than at sites with low crayfish densities. Insect diversity was lower in high- vs. low-density sites. No treatment effect was observed on growth or condition of individually marked fish. Short-term laboratory experiments demonstrated predatory interactions and competition for shelter between crayfish and Gila chub, desert sucker, and speckled dace. Crayfish used shelter more than fish, displaced fish from shelter, and frequently attacked fish. Fish never attacked crayfish, and only once displaced crayfish from shelter. In predation experiments, crayfish preyed upon all species, but preyed most heavily upon desert suckers. Fish never altered use of the water column in the presence of crayfish. Density manipulation experiments in a laboratory measured food competition between crayfish and two native fishes. Growth of Gila chub was less affected by crayfish than by increased density of Gila chub. Thus crayfish are not strong competitors with Gila chub for food. However, growth of flannelmouth sucker (Catostomus latipinnis) was negatively impacted by presence of crayfish. These laboratory experiments provide evidence that introduced crayfish can reduce fish growth by competition for food, and that native fishes are vulnerable to crayfish predation.
Gila River Basin Native Fishes Conservation Program
Doug Duncan; Robert W. Clarkson
2013-01-01
The Gila River Basin Native Fishes Conservation Program was established to conserve native fishes and manage against nonnative fishes in response to several Endangered Species Act biological opinions between the Bureau of Reclamation and the U.S. Fish and Wildlife Service on Central Arizona Project (CAP) water transfers to the Gila River basin. Populations of some Gila...
Summer food habits and trophic overlap of roundtail chub and creek chub in Muddy Creek, Wyoming
Quist, M.C.; Bower, M.R.; Hubert, W.A.
2006-01-01
Native fishes of the Upper Colorado River Basin have experienced substantial declines in abundance and distribution, and are extirpated from most of Wyoming. Muddy Creek, in south-central Wyoming (Little Snake River watershed), contains sympatric populations of native roundtail chub (Gila robusta), bluehead sucker, (Catostomus discobolus), and flannelmouth sucker (C. tatipinnis), and represents an area of high conservation concern because it is the only area known to have sympatric populations of all 3 species in Wyoming. However, introduced creek chub (Semotilus atromaculatus) are abundant and might have a negative influence on native fishes. We assessed summer food habits of roundtail chub and creek chub to provide information on the ecology of each species and obtain insight on potential trophic overlap. Roundtail chub and creek chub seemed to be opportunistic generalists that consumed a diverse array of food items. Stomach contents of both species were dominated by plant material, aquatic and terrestrial insects, and Fishes, but also included gastropods and mussels. Stomach contents were similar between species, indicating high trophic, overlap. No length-related patterns in diet were observed for either species. These results suggest that creek chubs have the potential to adversely influence the roundtail chub population through competition for food and the native fish assemblage through predation.
Helminth parasites of native Hawaiian freshwater fishes: an example of extreme ecological isolation.
Font, W F; Tate, D C
1994-10-01
The Hawaiian Islands harbor a depauperate native freshwater fish fauna comprised of 4 endemic gobies (Gobiidae) and 1 endemic sleeper (Eleotridae). We hypothesized that the natural helminth parasite community of these stream fishes would be depauperate because of colonizing constraints. In the absence of exotic fishes, native fishes in streams of Hanakapi'ai and Nu'alolo valleys harbored no adult helminth parasites. In Hakalau Stream on Hawai'i and Wainiha River on Kaua'i, we found introduced swordtails and guppies (Poeciliidae); here, the native gobioid fishes shared species of helminths with poeciliids. They were the nematode Camallanus cotti, the Asian tapeworm Bothriocephalus acheilognathi, and the leech Myzobdella lugubris. Such parasitological data should be incorporated into management plans for the conservation of native Hawaiian stream fishes as these parasites have been previously demonstrated to cause disease.
Pilliod, David S.; Arkle, Robert S.; Maxell, Bryce A.
2012-01-01
Studies have demonstrated negative effects of non-native, predatory fishes on native amphibians, yet it is still unclear why some amphibian populations persist, while others are extirpated, following fish invasion. We examined this question by developing habitat-based occupancy models for the long-toed salamander (Ambystoma macrodactylum) and nonnative fish using survey data from 1,749 water bodies across 470 catchments in the Northern Rocky Mountains, USA. We first modeled the habitat associations of salamanders at 468 fishless water bodies in 154 catchments where non-native fish were historically, and are currently, absent from the entire catchment. Wethen applied this habitat model to the complete data set to predict the probability of salamander occupancy in each water body, removing any effect of fish presence. Finally, we compared field-observed occurrences of salamanders and fish to modeled probability of salamander occupancy. Suitability models indicated that fish and salamanders had similar habitat preferences, possibly resulting in extirpations of salamander populations from entire catchments where suitable habitats were limiting. Salamanders coexisted with non-native fish in some catchments by using marginal quality, isolated (no inlet or outlet) habitats that remained fishless. They rarely coexisted with fish within individual water bodies and only where habitat quality was highest. Connectivity of water bodies via streams resulted in increased probability of fish invasion and consequently reduced probability of salamander occupancy.These results could be used to identify and prioritize catchments and water bodies where control measures would be most effective at restoring amphibian populations. Our approach could be useful as a framework for improved investigations into questions of persistence and extirpation of native species when non-native species have already become established.
Peter Landres; Shannon Meyer; Sue Matthews
2001-01-01
Many high-elevation lakes in designated wilderness are stocked with native and nonnative fish by state fish and game agencies to provide recreational fishing opportunities. In several areas, this practice has become controversial with state wildlife managers who support historical recreational use of wilderness, federal wilderness managers who assert that stocking...
Hermoso, Virgilio; Clavero, Miguel; Blanco-Garrido, Francisco; Prenda, José
2011-01-01
Mediterranean endemic freshwater fish are among the most threatened biota in the world. Distinguishing the role of different extinction drivers and their potential interactions is crucial for achieving conservation goals. While some authors argue that invasive species are a main driver of native species declines, others see their proliferation as a co-occurring process to biodiversity loss driven by habitat degradation. It is difficult to discern between the two potential causes given that few invaded ecosystems are free from habitat degradation, and that both factors may interact in different ways. Here we analyze the relative importance of habitat degradation and invasive species in the decline of native fish assemblages in the Guadiana River basin (southwestern Iberian Peninsula) using an information theoretic approach to evaluate interaction pathways between invasive species and habitat degradation (structural equation modeling, SEM). We also tested the possible changes in the functional relationships between invasive and native species, measured as the per capita effect of invasive species, using ANCOVA. We found that the abundance of invasive species was the best single predictor of natives' decline and had the highest Akaike weight among the set of predictor variables examined. Habitat degradation neither played an active role nor influenced the per capita effect of invasive species on natives. Our analyses indicated that downstream reaches and areas close to reservoirs had the most invaded fish assemblages, independently of their habitat degradation status. The proliferation of invasive species poses a strong threat to the persistence of native assemblages in highly fluctuating environments. Therefore, conservation efforts to reduce native freshwater fish diversity loss in Mediterranean rivers should focus on mitigating the effect of invasive species and preventing future invasions.
Danny C. Lee; James R. Sedell; Bruce E. Rieman; Russell F. Thurow; Jack E. Williams
1998-01-01
Continuing human activities threaten the highly prized aquatic resources of the interior Columbia basin. Precipitous declines in native species, particularly Pacific salmon, and a large influx of introduced species have radically altered the composition and distribution of native fishes. Fortunately, areas of relatively high aquatic integrity remain, much of it on...
Richness patterns in the parasite communities of exotic poeciliid fishes.
Dove, A D
2000-06-01
Three species of poeciliids (Gambusia holbrooki, Xiphophorus helleri and X. maculatus) and 15 species of ecologically similar native freshwater fishes (mainly eleotrids, ambassids, melanotaeniids and retropinnids) were examined for parasite richness to investigate parasite flux, qualitative differences, quantitative differences and the structuring factors in parasite communities in the 2 fish types in Queensland, Australia. Theory suggests that poeciliids would harbour depauperate parasite communities. Results supported this hypothesis; poeciliids harboured more species-poor parasite infracommunities and regional faunas than natives (P < 0.0001), despite greater sampling effort for the former. Cluster analysis of presence/absence data for poeciliids and the 6 most-sampled native fishes revealed that parasite communities of the 2 fish groups are qualitatively distinct; the proportion of parasite species with complex life-cycles was lower in poeciliids than in native species, and Myxosporea, Microspora, Coccidia and parasitic Crustacea were all absent from poeciliids. Limited exchange of parasite species has occurred between natives and poeciliids. Logistic ordinal regression analysis revealed that fish origin (exotic or native), environmental disturbance and host sex were all significant determinants of parasite community richness (P < 0.05). Theoretical modelling suggests that poeciliids are at a competitive advantage over native fishes because of their lack of parasites.
Moran, Clinton J; Gerry, Shannon P; O'Neill, Matthew W; Rzucidlo, Caroline L; Gibb, Alice C
2018-05-18
Morphological streamlining is often associated with physiological advantages for steady swimming in fishes. Though most commonly studied in pelagic fishes, streamlining also occurs in fishes that occupy high-flow environments. Before the installation of dams and water diversions, bonytail (Cyprinidae, Gila elegans ), a fish endemic to the Colorado River (USA), regularly experienced massive, seasonal flooding events. Individuals of G. elegans display morphological characteristics that may facilitate swimming in high-flow conditions, including a narrow caudal peduncle and a high aspect ratio caudal fin. We tested the hypothesis that these features improve sustained swimming performance in bonytail by comparing locomotor performance in G. elegans with that of the closely related roundtail chub ( Gila robusta ) and two non-native species, rainbow trout ( Oncorhynchus mykiss ) and smallmouth bass ( Micropterus dolomieu ), using a Brett-style respirometer and locomotor step-tests. Gila elegans had the lowest estimated drag coefficient and the highest sustained swimming speeds relative to the other three species. There were no detectible differences in locomotor energetics during steady swimming among the four species. When challenged by high-velocity water flows, the second native species examined in this study, G. robusta , exploited the boundary effects in the flow tank by pitching forward and bracing the pelvic and pectoral fins against the acrylic tank bottom to 'hold station'. Because G. robusta can station hold to prevent being swept downstream during high flows and G. elegans can maintain swimming speeds greater than those of smallmouth bass and rainbow trout with comparable metabolic costs, we suggest that management agencies could use artificial flooding events to wash non-native competitors downstream and out of the Colorado River habitat. © 2018. Published by The Company of Biologists Ltd.
Kiernan, Joseph D; Moyle, Peter B
2012-06-01
The fishes of Martis Creek, in the Sierra Nevada of California (USA), were sampled at four sites annually over 30 years, 1979-2008. This long-term data set was used to examine (1) the persistence and stability of the Martis Creek fish assemblage in the face of environmental stochasticity; (2) whether native and alien fishes responded differently to a natural hydrologic regime (e.g., timing and magnitude of high and low flows); and (3) the importance of various hydrologic and physical habitat variables in explaining the abundances of native and alien fish species through time. Our results showed that fish assemblages were persistent at all sample sites, but individual species exhibited marked interannual variability in density, biomass, and relative abundance. The density and biomass of native fishes generally declined over the period of study, whereas most alien species showed no significant long-term trends. Only alien rainbow trout increased in both density and biomass at all sites over time. Redundancy analysis identified three hydrologic variables (annual 7-day minimum discharge, maximum winter discharge, and number of distinct winter floods) and two habitat variables (percentage of pool habitat and percentage of gravel substrate) that each explained a significant portion of the annual variation in fish assemblage structure. For alien taxa, their proportional contribution to the total fish assemblage was inversely related to mean annual streamflow, one-day maximum discharge in both winter and spring, and the frequency of springtime floods. Results of this study highlight the need for continuous annual monitoring of streams with highly variable flow regimes to evaluate shifts in fish community structure. Apparent successes or failures in stream management may appear differently depending on the time series of available data.
Parasites of native and exotic freshwater fishes in south-western Australia.
Lymbery, A J; Hassan, M; Morgan, D L; Beatty, S J; Doupé, R G
2010-05-01
In this study, 1429 fishes of 18 different species (12 native and six exotic) were sampled from 29 localities to compare the levels of parasitism between native and exotic fish species and to examine the relationship between environmental degradation and parasite diversity. Forty-four putative species of parasites were found and most of these appear to be native parasites, which have not previously been described. Two parasite species, Lernaea cyprinacea and Ligula intestinalis, are probably introduced. Both were found on or in a range of native fish species, where they may cause severe disease. Levels of parasitism and parasite diversity were significantly greater in native fishes than in exotic species, and this may contribute to an enhanced demographic performance and competitive ability in invading exotics. Levels of parasitism and parasite diversity in native fishes were negatively related to habitat disturbance, in particular to a suite of factors that indicate increased human use of the river and surrounding environment. This was due principally to the absence in more disturbed habitats of a number of species of endoparasites with complex life cycles, involving transmission between different host species.
Melvin L. Warren; Brooks M. Burr; Stephen J. Walsh; Henry L. Bart; Robert C. Cashner; David A. Etnier; Byron J. Freeman; Bernard R. Kuhajda; Richard L. Mayden; Henry W. Robison; Stephen T. Ross; Wayne C. Starnes
2000-01-01
The Southeastern Fishes Council Technical Advisory Committee reviewed the diversity, distribution, and status of all native freshwater and diadromous fishes across 51 major drainage units of the Southern United States. The Southern United States supports more native fishes than any area of comparable size on the North American continent north of Mexico, but also has a...
Indian Summer: A "Hands-On, Feet-Wet" Approach to Science Education.
ERIC Educational Resources Information Center
Galindo, Ed; Barta, Jim
2001-01-01
A summer fish recovery program along the Salmon River (Idaho) involves Native American high school students in science, technology, and research within a cultural and environmental context. The positive attitudes and work ethic of Native students and the research and study skills they acquired demonstrate that Native students succeed when their…
DOE Office of Scientific and Technical Information (OSTI.GOV)
U.S. Fish & Wildlife Service, Abernathy Fish Technology Center
2008-12-01
Many hatchery programs for steelhead pose genetic or ecological risks to natural populations because those programs release or outplant fish from non-native stocks. The goal of many steelhead programs has been to simply provide 'fishing opportunities' with little consideration given to conservation concerns. For example, the Washington Department of Fish and Wildlife (WDFW) has widely propagated and outplanted one stock of winter-run steelhead (Chambers Creek stock) and one stock of summer-run steelhead (Skamania stock) throughout western Washington. Biologists and managers now recognize potential negative effects can occur when non-native hatchery fish interact biologically with native populations. Not only do non-nativemore » stocks pose genetic and ecological risks to naturally spawning populations, but non-native fish stray as returning adults at a much higher rate than do native fish (Quinn 1993). Biologists and managers also recognize the need to (a) maintain the genetic resources associated with naturally spawning populations and (b) restore or recover natural populations wherever possible. As a consequence, the U.S. Fish & Wildlife Service (USFWS) and the NOAA Fisheries have been recommending a general policy that discourages the use of non-native hatchery stocks and encourages development of native broodstocks. There are two primary motivations for these recommendations: (1) reduce or minimize potential negative biological effects resulting from genetic or ecological interactions between hatchery-origin and native-origin fish and (2) use native broodstocks as genetic repositories to potentially assist with recovery of naturally spawning populations. A major motivation for the captive-rearing work described in this report resulted from NOAA's 1998 Biological Opinion on Artificial Propagation in the Columbia River Basin. In that biological opinion (BO), NOAA concluded that non-native hatchery stocks of steelhead jeopardize the continued existence of U.S. Endangered Species Act (ESA)-listed, naturally spawning populations in the Columbia River Basin. As a consequence of that BO, NOAA recommended - as a reasonable and prudent alternative (RPA) - that federal and state agencies phase out non-native broodstocks of steelhead and replace them with native broodstocks. However, NOAA provided no guidance on how to achieve that RPA. The development of native broodstocks of hatchery steelhead can potentially pose unacceptable biological risks to naturally spawning populations, particularly those that are already listed as threatened or endangered under the ESA. The traditional method of initiating new hatchery broodstocks of anadromous salmonid fishes is by trapping adults during their upstream, spawning migration. However, removing natural-origin adults from ESA listed populations may not be biologically acceptable because such activities may further depress those populations via 'broodstock mining'. In addition, trapping adult steelhead may be logistically unfeasible in many subbasins due to high water flows in the spring, when steelhead are moving upstream to spawn, that will often 'blow out' temporary weirs. Additional risks associated with trapping adults include genetic founder effects and difficulties meeting minimum, genetic effective number of breeders without 'mining' the wild population to potential extinction. As a result, alternative methods for developing native broodstocks are highly desired. One alternative for developing native broodstocks, particularly when the collection of adults is logistically unfeasible or biologically unacceptable, is captive rearing of natural-origin juveniles to sexual maturity. In this approach, pre-smolt juveniles are collected from the stream or watershed for which a native broodstock is desired, and those juveniles are raised to sexual maturity in a hatchery. Those hatchery-reared adults then become the broodstock source for gametes and initial progeny releases. Such a captive rearing program offers many genetic advantages over traditional adult-trapping programs for developing native broodstocks: (1) Large numbers of juveniles can be collected from the wild with only minimal impacts to naturally spawning populations because juvenile (age 0+parr)-to-adult survivals are typically very small (<1%) under natural conditions. (2) The genetic base of the broodstock (i.e. genetic effective population size) can be substantially larger for juveniles than adults because juveniles can theoretically represent the offspring of all adults that spawned successfully within a stream or watershed, as opposed to trapping only a small portion of returning adults for broodstock. (3) Collecting juveniles for broodstock can substantially reduce the risk of genetically 'swamping' naturally spawning populations with hatchery-origin fish (i.e. via a 'Ryman-Laikre effect') as occurs when hatchery-released fish represent the progeny of a relatively small number of trapped adults.« less
Landscape-scale determinants of native and nonnative Great Plains fish distributions
Stewart, David R.; Walters, Annika W.; Rahel, Frank J.
2015-01-01
The similar relationships between native and non-native fish species richness are likely evidence that they share similar ecological rules, which supports that non-native species become naturalized and they may be affected by the same environmental factors that determine distribution of native species.
Culvert roughness elements for native Utah fish passage : phase II.
DOT National Transportation Integrated Search
2012-04-01
Native fishes have become an increasingly important concern when designing fish passable culverts. Many operational culverts constrict waterways which increase velocities and prevent upstream passage of small fish species. The current method to ensur...
Paretti, Nicholas; Brasher, Anne M. D.; Pearlstein, Susanna L.; Skow, Dena M.; Gungle, Bruce W.; Garner, Bradley D.
2018-05-15
A 3-year study was undertaken to evaluate the suitability of the available modeling tools for characterizing environmental flows in the middle Verde River watershed of central Arizona, describe riparian vegetation throughout the watershed, and estimate sediment mobilization in the river. Existing data on fish and macroinvertebrates were analyzed in relation to basin characteristics, flow regimes, and microhabitat, and a pilot study was conducted that sampled fish and macroinvertebrates and the microhabitats in which they were found. The sampling for the pilot study took place at five different locations in the middle Verde River watershed. This report presents the results of this 3-year study. The Northern Arizona Groundwater Flow Model (NARGFM) was found to be capable of predicting long-term changes caused by alteration of regional recharge (such as may result from climate variability) and groundwater pumping in gaining, losing, and dry reaches of the major streams in the middle Verde River watershed. Over the period 1910 to 2006, the model simulated an increase in dry reaches, a small increase in reaches losing discharge to the groundwater aquifer, and a concurrent decrease in reaches gaining discharge from groundwater. Although evaluations of the suitability of using the NARGFM and Basin Characteristic Model to characterize various streamflow intervals showed that smallerscale basin monthly runoff could be estimated adequately at locations of interest, monthly stream-flow estimates were found unsatisfactory for determining environmental flows.Orthoimagery and Moderate Resolution Imaging Spectroradiometer data were used to quantify stream and riparian vegetation properties related to biotic habitat. The relative abundance of riparian vegetation varied along the main channel of the Verde River. As would be expected, more upland plant species and fewer lowland species were found in the upper-middle section compared to the lower-middle section, and vice-versa. Vegetation changes within the upper-middle and lower-middle reaches are related to differences in climate and hydrology. In general, the riparian vegetation of the middle Verde River watershed is that of a healthy ecosystem’s mixed age, mixed patch structure, likely a result of the mostly unaltered disturbance regime.The frequency of in-river hydrogeomorphic features (pool, riffle, run) varied along the middle Verde River channel. There was a greater abundance of riffle habitat in the upper-middle reach; the lower-middle reach included more pool habitat. The Oak Creek tributary was more homogenous in geomorphic stream habitat composition than West Clear Creek, where runs dominated the upper reaches and pools dominated many of the lower reaches.On the basis of the period of record and discharges recorded at 15-minute intervals, five flows were found to reach the gravel-transport threshold. Sediment mobilization computed with flows averaged over daily time steps yielded just three flows that reached the gravel-transport threshold, and monthly averaged flows yielded none. In the middle Verde River watershed, 15-minute data should be used when possible to evaluate sediment transport in the river system.Data from more than 300 fish surveys conducted from 1992 to 2011 were analyzed using two schemes, one that divided the river into five reaches based on basin characteristics, and a second that divided the river into five reaches based on degree of flow alteration (specifically, diversions). Fish community metrics and assemblage data were used to analyze patterns of species composition and abundance in the two approaches. Overall, native and non-native species were regularly interacting and probably competing for similar resources. Fish abundances were also analyzed in response to floods and other flow metrics. Although the data are limited, native fish abundances increased more rapidly than non-native fish abundances in response to large floods. The basin-characteristic reach analysis showed native fish in greater abundance in the upper-middle reaches of the Verde River watershed and generally decreasing with downstream distance. The median relative abundance of native fish decreased by 50 percent from reach 1 to reach 5. Using the reach scheme based on degree of flow alteration, nondiverted reaches were found to have a greater abundance of native fish than diverted reaches. In heavily diverted reaches, non-native species outnumbered native species.Fish metrics and stream-flow metrics for the 30, 90, and 365-day periods before collection were computed and the results analyzed statistically. Only abundance of all fish species was associated with the 30-day flow metrics. The 90-day flow metrics were generally positively associated with fish metrics, whereas the 365-day flow metrics had more negative correlations. In particular, significant relations were found between fish metrics and the magnitude and frequency of high flows, including maximum monthly flow, median annual number of high-flow events, and median annual maximum streamflow. Native sucker (Catostomidae) populations tended to decrease in periods of extended base flow, and fish in the non-native sunfish family (Centrarchidae) decreased in periods of flashy, high magnitude flows.A pilot study surveyed fish at five locations in the upper part of the middle Verde River watershed as a means to measure microhabitat availability and quantify native and non-native fish use of that available microhabitat. Results indicated that native and non-native species exhibit some clear differences in microhabitat use. Although at least some native and non-native fish were found in each velocity, depth, and substrate category, preferential microhabitat use was common. On a percentage basis, non-native species had a strong preference for slow-moving and deeper water with silt and sand substrate, with a secondary preference for faster moving and very shallow water and a coarse gravel substrate. Native species showed a general preference for somewhat faster, moderate depth water over coarse gravel and had no clear secondary preference.Macroinvertebrate-variables index period, high-flow year, and collection location (upper-middle Verde River, lowermiddle Verde River, or Verde River tributaries) were found to be important explanatory variables in differentiating among community metrics. Overall richness (number of unique taxa), Shannon’s diversity index, and the percent of the most dominant taxa were all highly correlated, but their response to each macroinvertebrate variable was different. The percentage of mayfly (order Ephemeroptera) taxa was significantly higher in Oak Creek and the upper-middle and lower-middle Verde River reaches, locations which have higher flows and more urbanization than other reaches. When community metrics were related to hydrologic metrics, caddisfly (order Trichoptera) populations appeared to increase and mayfly populations to decrease in response to less flashy and more stable streamflows. Conversely, caddisfly populations appeared to decrease and mayfly populations to increase in response to greater flow variability.Six locations along the Verde River were sampled for macroinvertebrates as part of a pilot study associated with this report—(1) below Granite Creek, (2) near Campbell Ranch, (3) at the U.S. Geological Survey Paulden gage, (4) at the Perkinsville Bridge, (5) at the USGS Clarkdale gage, and (6) near the Reitz Ranch property. A nonmetric multidimensional scaling ordination of macroinvertebrate assemblages showed that the Verde River below Granite Creek site was different from the five other sites and that the Perkinsville Bridge and near Reitz Ranch samples had similar community structure. The near Campbell Ranch and Paulden gage locations had similar microhabitat characteristics, with the exception of riparian cover, yet the assemblage structure was very different. The different community composition at Verde River below Granite Creek was likely due to it having the smallest substrate sizes, lowest velocities, shallowest depths, and most riparian cover of the six sites.
Tran, Thi Nhat Quyen; Jackson, Michelle C; Sheath, Danny; Verreycken, Hugo; Britton, J Robert
2015-07-01
Ecological theory attempts to predict how impacts for native species arise from biological invasions. A fundamental question centres on the feeding interactions of invasive and native species: whether invasion will result in increased interspecific competition, which would result in negative consequences for the competing species, or trophic niche divergence, which would facilitate the invader's integration into the community and their coexistence with native species. Here, the feeding interactions of a highly invasive fish, topmouth gudgeon Pseudorasbora parva, with three native and functionally similar fishes were studied to determine whether patterns of either niche overlap or divergence detected in mesocosm experiments were apparent between the species at larger spatial scales. Using stable isotope analysis, their feeding relationships were assessed initially in the mesocosms (1000 L) and then in small ponds (<400 m(2) ) and large ponds (>600 m(2) ). In the mesocosms, a consistent pattern of trophic niche divergence was evident between the sympatric fishes, with niches shifting further apart in isotopic space than suggested in allopatry, revealing that sharing of food resources was limited. Sympatric P. parva also had a smaller niche than their allopatric populations. In eight small ponds where P. parva had coexisted for several years with at least one of the fish species used in the mesocosms, strong patterns of niche differentiation were also apparent, with P. parva always at a lower trophic position than the other fishes, as also occurred in the mesocosms. Where these fishes were sympatric within more complex fish communities in the large ponds, similar patterns were also apparent, with strong evidence of trophic niche differentiation. Aspects of the ecological impacts of P. parva invasion for native communities in larger ponds were consistent with those in the mesocosm experiments. Their invasion resulted in divergence in trophic niches, partly due to their reduced niche widths when in sympatry with other species, facilitating their coexistence in invaded ecosystems. Our study highlights the utility of controlled mesocosm studies for predicting the trophic relationships that can develop from introductions of non-native species into more complex ecosystems and at larger spatial scales. © 2015 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.
Lake Michigan: Man's effects on native fish stocks and other biota
Wells, LaRue; McLain, Alberton L.
1973-01-01
Exploitation was largely responsible for the changes in Lake Michigan fish stocks before the invasion of the smelt, and probably before the invasion of the sea lamprey. The lamprey and alewife, however, have exerted a greater impact than the fishery on native fish populations in recent decades. Accelerated eutrophication and other pollution, although important, have not equalled the other factors in causing changes in native fish populations.
The offshore benthic fish community
Lantry, Brian F.; Lantry, Jana R.; Weidel, Brian C.; Walsh, Maureen; Hoyle, James A.; Schaner, Teodore; Neave, Fraser B.; Keir, Michael
2014-01-01
The offshore benthic fish community will be composed of self-sustaining native fishes characterized by lake trout as the top predator, a population expansion of lake whitefish from northeastern waters to other areas of the lake, and rehabilitated native prey fishes.
NASA Astrophysics Data System (ADS)
Sakuma, Masami; Kunimatsu, Fumihiro; Tsuchiya, Taku; Kawamura, Makiko; Fujita, Hiroshi
Largemouth bass and Bluegill, major invasive alien fish species in Japan, have been extending their habitat ranges over not only Lake Biwa and the lagoons but also surrounding waters connected to them through small rivers and canals. Their increasing number is bringing about the reduction in the number of native fish species. To prevent the spread of these alien species through small rivers and canals during breeding season of the native fish (crucian carp), this study experimentally examined the effect of a submerged weir on controlling upstream migration of the alien species and the native fish. As a result of the experiment, the ratio of the alien species migrating upstream decreased as the weir height rose, whereas the ratio did not show the same trend in the case of the native fish. The ratio of the alien species also decreased as the overflow velocity over the weir rose. On the other hand, the ratio of the native fish increased as the overflow velocity rose up to 1.0m/s and decreased thereafter. These results suggest that the submerged weir may control upstream migration of the alien species to surrounding waters through small rivers and canals without interfering with the reproductive migration of the native fish.
Trophic interactions between native and introduced fish species in a littoral fish community.
Monroy, M; Maceda-Veiga, A; Caiola, N; De Sostoa, A
2014-11-01
The trophic interactions between 15 native and two introduced fish species, silverside Odontesthes bonariensis and rainbow trout Oncorhynchus mykiss, collected in a major fishery area at Lake Titicaca were explored by integrating traditional ecological knowledge and stable-isotope analyses (SIA). SIA suggested the existence of six trophic groups in this fish community based on δ(13)C and δ(15)N signatures. This was supported by ecological evidence illustrating marked spatial segregation between groups, but a similar trophic level for most of the native groups. Based on Bayesian ellipse analyses, niche overlap appeared to occur between small O. bonariensis (<90 mm) and benthopelagic native species (31.6%), and between the native pelagic killifish Orestias ispi and large O. bonariensis (39%) or O. mykiss (19.7%). In addition, Bayesian mixing models suggested that O. ispi and epipelagic species are likely to be the main prey items for the two introduced fish species. This study reveals a trophic link between native and introduced fish species, and demonstrates the utility of combining both SIA and traditional ecological knowledge to understand trophic relationships between fish species with similar feeding habits. © 2014 The Fisheries Society of the British Isles.
Phelps, Quinton E; Tripp, Sara J; Bales, Kyle R; James, Daniel; Hrabik, Robert A; Herzog, David P
2017-01-01
Numerous studies throughout North America allege deleterious associations among invasive Asian Carp and native fishes; however, no empirical evidence on a system-wide scale exists. We used Mississippi River Basin fish community data collected by the Long Term Resource Monitoring program and the Missouri Department of Conservation to evaluate possible interaction between Asian Carp and native fishes. Results from two decades of long-term monitoring throughout much of the Mississippi River suggest that Silver Carp relative abundance has increased while relative abundance (Bigmouth Buffalo [F 3, 8240 = 6.44, P<0.01] and Gizzard Shad [F 3, 8240 = 31.04, P<0.01]) and condition (Bigmouth Buffalo [slope = -0.11; t = -1.71; P = 0.1014] and Gizzard Shad [slope = -0.39; t = -3.02; P = 0.0073]) of native planktivores have declined. Floodplain lake qualitative evaluations yielded similar results; floodplain lake fish communities were likely altered (i.e., reductions in native species) by Silver Carp. Furthermore, laboratory experiments corroborated field evidence; Silver Carp negatively influence native planktivores through competition for prey (all comparisons, P > 0.05). To this end, this study provides evidence that Silver Carp are likely adversely influencing native fishes; however, mere presence of Silver Carp in the system does not induce deleterious effects on native fishes. To the best of our knowledge, this evaluation is the first to describe the effects of Asian Carp throughout the Mississippi River Basin and could be used to reduce the effects of Asian Carp on native biota through an integrated pest management program as suggested by congressional policy. Despite the simplicity of the data analyzed and approach used, this study provides a framework for beginning to identify the interactions of invasive fish pests on native fishes (i.e., necessary first step of integrated pest management). However, knowledge gaps remain. We suggest future efforts should conduct more in depth analyses (i.e., multivariate statistical approaches) that investigate the influence on all native species.
Tripp, Sara J.; James, Daniel; Hrabik, Robert A.; Herzog, David P.
2017-01-01
Numerous studies throughout North America allege deleterious associations among invasive Asian Carp and native fishes; however, no empirical evidence on a system-wide scale exists. We used Mississippi River Basin fish community data collected by the Long Term Resource Monitoring program and the Missouri Department of Conservation to evaluate possible interaction between Asian Carp and native fishes. Results from two decades of long-term monitoring throughout much of the Mississippi River suggest that Silver Carp relative abundance has increased while relative abundance (Bigmouth Buffalo [F 3, 8240 = 6.44, P<0.01] and Gizzard Shad [F 3, 8240 = 31.04, P<0.01]) and condition (Bigmouth Buffalo [slope = -0.11; t = -1.71; P = 0.1014] and Gizzard Shad [slope = -0.39; t = -3.02; P = 0.0073]) of native planktivores have declined. Floodplain lake qualitative evaluations yielded similar results; floodplain lake fish communities were likely altered (i.e., reductions in native species) by Silver Carp. Furthermore, laboratory experiments corroborated field evidence; Silver Carp negatively influence native planktivores through competition for prey (all comparisons, P > 0.05). To this end, this study provides evidence that Silver Carp are likely adversely influencing native fishes; however, mere presence of Silver Carp in the system does not induce deleterious effects on native fishes. To the best of our knowledge, this evaluation is the first to describe the effects of Asian Carp throughout the Mississippi River Basin and could be used to reduce the effects of Asian Carp on native biota through an integrated pest management program as suggested by congressional policy. Despite the simplicity of the data analyzed and approach used, this study provides a framework for beginning to identify the interactions of invasive fish pests on native fishes (i.e., necessary first step of integrated pest management). However, knowledge gaps remain. We suggest future efforts should conduct more in depth analyses (i.e., multivariate statistical approaches) that investigate the influence on all native species. PMID:28873472
Ongoing removals of invasive lionfish in Honduras and their effect on native Caribbean prey fishes.
Peiffer, Friederike; Bejarano, Sonia; Palavicini de Witte, Giacomo; Wild, Christian
2017-01-01
The invasion of Indo-Pacific lionfish is one of the most pressing concerns in the context of coral reef conservation throughout the Caribbean. Invasive lionfish threaten Caribbean fish communities by feeding on a wide range of native prey species, some of which have high ecological and economic value. In Roatan (Honduras) a local non-governmental organisation (i.e. Roatan Marine Park) trains residents and tourists in the use of spears to remove invasive lionfish. Here, we assess the effectiveness of local removal efforts in reducing lionfish populations. We ask whether reefs subject to relatively frequent removals support more diverse and abundant native fish assemblages compared to sites were no removals take place. Lionfish biomass, as well as density and diversity of native prey species were quantified on reefs subject to regular and no removal efforts. Reefs subject to regular lionfish removals (two to three removals month -1 ) with a mean catch per unit effort of 2.76 ± 1.72 lionfish fisher -1 h -1 had 95% lower lionfish biomass compared to non-removal sites. Sites subject to lionfish removals supported 30% higher densities of native prey-sized fishes compared to sites subject to no removal efforts. We found no evidence that species richness and diversity of native fish communities differ between removal and non-removal sites. We conclude that opportunistic voluntary removals are an effective management intervention to reduce lionfish populations locally and might alleviate negative impacts of lionfish predation. We recommend that local management and the diving industry cooperate to cost-effectively extend the spatial scale at which removal regimes are currently sustained.
Ongoing removals of invasive lionfish in Honduras and their effect on native Caribbean prey fishes
Palavicini de Witte, Giacomo; Wild, Christian
2017-01-01
The invasion of Indo-Pacific lionfish is one of the most pressing concerns in the context of coral reef conservation throughout the Caribbean. Invasive lionfish threaten Caribbean fish communities by feeding on a wide range of native prey species, some of which have high ecological and economic value. In Roatan (Honduras) a local non-governmental organisation (i.e. Roatan Marine Park) trains residents and tourists in the use of spears to remove invasive lionfish. Here, we assess the effectiveness of local removal efforts in reducing lionfish populations. We ask whether reefs subject to relatively frequent removals support more diverse and abundant native fish assemblages compared to sites were no removals take place. Lionfish biomass, as well as density and diversity of native prey species were quantified on reefs subject to regular and no removal efforts. Reefs subject to regular lionfish removals (two to three removals month−1) with a mean catch per unit effort of 2.76 ± 1.72 lionfish fisher−1 h−1 had 95% lower lionfish biomass compared to non-removal sites. Sites subject to lionfish removals supported 30% higher densities of native prey-sized fishes compared to sites subject to no removal efforts. We found no evidence that species richness and diversity of native fish communities differ between removal and non-removal sites. We conclude that opportunistic voluntary removals are an effective management intervention to reduce lionfish populations locally and might alleviate negative impacts of lionfish predation. We recommend that local management and the diving industry cooperate to cost-effectively extend the spatial scale at which removal regimes are currently sustained. PMID:29062597
Unintended consequences and trade-offs of fish passage
McLaughlin, Robert L.; Smyth, Eric R.; Castro-Santos, Theodore; Jones, Michael L.; Koops, Marten A.; Pratt, Thomas C.; Vélez-Espino, Luis-Antonio
2012-01-01
We synthesized evidence for unintended consequences and trade-offs associated with the passage of fishes. Provisioning of fish passageways at dams and dam removals are being carried out increasingly as resource managers seek ways to reduce fragmentation of migratory fish populations and restore biodiversity and nature-like ecosystem services in tributaries altered by dams. The benefits of provisioning upstream passage are highlighted widely. Possible unwanted consequences and trade-offs of upstream passage are coming to light, but remain poorly examined and underappreciated. Unintended consequences arise when passage of native and desirable introduced fishes is delayed, undone (fallback), results in patterns of movement and habitat use that reduce Darwinian fitness (e.g. ecological traps), or is highly selective taxonomically and numerically. Trade-offs arise when passage decisions intended to benefit native species interfere with management decisions intended to control the unwanted spread of non-native fishes and aquatic invertebrates, or genes, diseases and contaminants carried by hatchery and wild fishes. These consequences and trade-offs will vary in importance from system to system and can result in large economic and environmental costs. For some river systems, decisions about how to manage fish passage involve substantial risks and could benefit from use of a formal, structured process that allows transparent, objective and, where possible, quantitative evaluation of these risks. Such a process can also facilitate the design of an adaptive framework that provides valuable insights into future decisions.
Cultural and health implications of fish advisories in a Native American community
Hoover, Elizabeth
2014-01-01
Introduction Fish advisories are issued in an effort to protect human health from exposure to contaminants, but Native American communities may suffer unintended health, social, and cultural consequences as a result of warnings against eating local fish. This paper focuses on the Mohawk community of Akwesasne, which lies downstream from a Superfund site, and explores how fish advisories have impacted fish consumption and health. Methods 65 Akwesasne community members were interviewed between March 2008 and April 2009. Interviews were semi-structured, lasted from 30–90 minutes and consisted of open-ended questions about the impacts of environmental contamination on the community. Detailed field notes were also maintained during extensive visits between 2007–2011. Interviews were transcribed, and these transcripts as well as the field notes were analyzed in NVivo 8.0. This research received approval from the Akwesasne Task Force on the Environment Research Advisory Committee, as well as the Brown University Institutional Review Board. Results Three-quarters of the 50 Akwesasne Mohawks interviewed have ceased or significantly curtailed their local fish consumption due to the issuance of fish advisories or witnessing or hearing about deformities on fish. Many of these respondents have turned to outside sources of fish, from other communities or from grocery stores. This change in fish consumption concerns many residents because cultural and social connections developed around fishing are being lost and because fish has been replaced with high-fat high-carb processed foods, which has led to other health complications. One-quarter of the 50 interviewees still eat local fish, but these are generally middle-aged or older residents; fish consumption no longer occurs in the multi-generational social context it once did. Conclusions Human health in Native American communities such as Akwesasne is intimately tied to the health of the environment. Fish advisories should not be used as an institutional control to protect humans from exposure to contaminants; if Akwesasne are to achieve optimal health, the contaminated environment has to be remediated to a level that supports clean, edible fish. PMID:25243106
Information to support to monitoring and habitat restoration on Ash Meadows National Wildlife Refuge
Scoppettone, G. Gary
2013-01-01
The Ash Meadows National Wildlife Refuge staff focuses on improving habitat for the highest incidence of endemic species for an area of its size in the continental United States. Attempts are being made to restore habitat to some semblance of its pre-anthropogenic undisturbed condition, and to provide habitat conditions to which native plant and animal species have evolved. Unfortunately, restoring the Ash Meadows’ Oases to its pre-anthropogenic undisturbed condition is almost impossible. First, there are constraints on water manipulation because there are private holdings within the refuge boundary; second, there has been at least one species extinction—the Ash Meadows pool fish (Empetrichthys merriami). It is also quite possible that thermal endemic invertebrate species were lost before ever being described. Perhaps the primary obstacle to restoring Ash Meadows to its pre-anthropogenic undisturbed conditions is the presence of invasive species. However, invasive species, such as red swamp crayfish (Procambarus clarki) and western mosquitofish (Gambusia affinis), are a primary driving force in restoring Ash Meadows’ spring systems, because under certain habitat conditions they can all but replace native species. Returning Ash Meadows’ physical landscape to some semblance of its pre-anthropogenic undisturbed condition through natural processes may take decades. Meanwhile, the natural dissolution of concrete and earthen irrigation channels threatens to allow cattail marshes to flourish instead of spring-brooks immediately downstream of spring discharge. This successional stage favors non-native crayfish and mosquitofish over the native Amargosa pupfish (Cyprinodon nevadensis). Thus, restoration is needed to control non-natives and to promote native species, and without such intervention the probability of native fish reduction or loss, is anticipated. The four studies in this report are intended to provide information for restoring native fish habitat and for monitoring native fish populations in relation to restoration efforts on the Ash Meadows National Wildlife Refuge. There are no precise records on conditions of each of the spring systems prior to anthropogenic alteration; however, fostering conditions that favor native over non-natives will be key to habitat restoration. Information regarding native species carbon source is needed to create habitat that favors native species, thus habitat restoration fostering food stuff consumed by native species should be considered in restoration efforts. In compiling data for the first part of this report, we tracked carbon source for native and non-native species at four stations along the Jackrabbit Spring system. Thus, we were able to contrast carbon source in warm- and cool-water habitats. Habitat in Jackrabbit Spring was improved for native fishes in 2007. The second paper in this report focuses on native fish populations in Jackrabbit Spring system pre- and post-restoration. Much of the Ash Meadows Oases is marsh habitat where non-native red swamp crayfish and western mosquitofish are often abundant, to the detriment of non-natives. Because marsh habitat is broadly represented in the Ash Meadows landscape, establishing marsh habitat most conducive to the native fishes is important to the restoration effort, and the third paper addresses marsh habitat type with the relative abundance of fishes and crayfish. There are previous years of monitoring Ash Meadows’ native fish populations, but not all monitoring occurred at the same time of year. Desert-fish populations sometimes undergo seasonal fluctuation, so it might not be valid to compare population trends using difference seasons. For report four, we tracked a closed population of Amargosa pupfish (Cyprinodon nevadensis) year round to track seasonal trends. Knowledge of seasonal trends is important in tracking changes of populations pre- and post-restoration.
Conserving large-river fishes: Is the highway analogy an appropriate paradigm
Galat, D.L.; Zweimuller, I.
2001-01-01
A tenet of the flood pulse concept, the highway analogy, states that the mare channel of large floodplain rivers is used by fishes mainly as a route for gaining access to floodplain habitats. We examined this proposition by analyzing habitat use for freshwater fishes in 4 large rivers in the United States (Colorado, Columbia, Mississippi, Missouri) and 4 in Europe (Danube, Rhine, Rho??ne, Volga). Fish species from floodplain segments of each river were classified as fluvial specialist, fluvial dependent, and macrohabitat generalist based on literature and expert opinion. We also summarized the proportion of imperiled and introduced fishes present in each of these categories. The high proportion (mean ?? 1 SD = 29 ?? 17.5%) of fluvial specialist fishes inhabiting north-temperate large rivers was inconsistent with the highway analogy. Most members of the families Petromyzontidae, Acidpenseridae, Hiodontidae, Osmeridae, Salmonidae, and Gobiidae require flowing water during some life stage. Between 29 and 100% of the native fish assemblage was of conservation concern, and from 50 to 85% of these fishes required riverine habitats to complete their life cycles. Macrohabitat generalists are adapted to capitalize on floodplain habitats and composed from 44 to 96% of introduced fishes in the rivers studied. Habitat diversity inherent in main-channel complexes of unaltered large rivers and reestablished in regulated large rivers is essential to meet life-history needs of native fluvial fishes while discouraging expansion of introduced species. Restoration of north-temperate large rivers and their native fish fauna should incorporate the dynamic interplay among main channel, floodplain, and tributary habitats and processes.
What percentage of the West's 209,381 kilometers of streams and rivers contain fish? What proportion contains only native fish? Do aliens dominate the fish fauna of streams in any region or state? What are the ranges and relative densities of the most common fish, native and al...
Barriers, invasion, and conservation of native salmonids in coldwater streams [Box 18.2
Bruce Rieman; Michael Young; Kurt Fausch; Jason Dunham; Douglas Peterson
2010-01-01
Habitat loss and fragmentation are threats to persistence of many native fish populations. Invading nonnative species that may restrict or displace native species are also important. These two issues are particularly relevant for native salmonids that are often limited to remnant habitats in cold, headwater streams. On the surface, reversing threats to native fishes...
Brown, L.R.; Moyle, P.B.
1997-01-01
We examined invasions of non-native fishes into the Eel River, California. At least 16 species of fish have been introduced into the drainage which originally supported 12-14 fish species. Our study was prompted by the unauthorized introduction in 1979 of Sacramento squawfish, Ptychocheilus grandis, a large predatory cyprinid. From 1986 to 1990, we conducted growth and diet studies of squaw fish, conducted intensive surveys of the distribution and habitat associations of both native and introduced species, and examined the nature of species-habitat and interspecies relationships. We found no evidence for increased growth or expanded feeding habits, compared to native populations, of Sacramento squawfish as they invaded the Eel River drainage. Ten of the introduced species were well established, with four species limited to a reservoir and six species established in streams. The success or failure of introductions of stream species appeared to be a function of the ability of a species to survive the fluctuating, highly seasonal, flow regime. The present mixture of native and exotic species has not formed stable fish assemblages but it seems likely that four habitat-associated assemblages will develop. The overall effect of the successful species introductions has been to assemble a group of species, with some exceptions, that are native to and occur together in many California streams. The assemblages now forming are similar to those found in other California streams. The assemblage characterized by squawfish and suckers is likely to be resistant to invasion, in the absence of human caused habitat modifications.
Improving non-native fish larvae detection based on temporal habitat use.
As part of the development of an early detection monitoring strategy for non-native fishes, larval fish surveys have been conducted since 2012 in the St. Louis River estuary. Survey data demonstrates considerable variability in fish abundance and species assemblages across habit...
An experiment to control nonnative fish in the Colorado River, Grand Canyon, Arizona
Coggins,, Lewis G.; Yard, Michael D.
2011-01-01
The humpback chub (Gila cypha) is an endangered native fish found only in the Colorado River Basin. In Grand Canyon, most humpback chub are found in the Little Colorado River and its confluence with the Colorado River. For decades, however, nonnative rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta), which prey on and compete with native fish, have dominated the Grand Canyon fish community. Between 2003 and 2006, scientists with the U.S. Geological Survey and Arizona Game and Fish Department experimentally removed 23,266 nonnative fish from a 9.4-mile-long reach of the Colorado River near where it joins the Little Colorado River. During the experiment, rainbow trout were reduced by as much as 90% and native fish abundance apparently increased in the reach. Concurrent environmental changes and a decrease in rainbow trout throughout the river make it difficult to determine if the apparent increase in native fish was the result of the experiment.
Environmental DNA for freshwater fish monitoring: insights for conservation within a protected area.
Fernandez, Sara; Sandin, Miguel M; Beaulieu, Paul G; Clusa, Laura; Martinez, Jose L; Ardura, Alba; García-Vázquez, Eva
2018-01-01
Many fish species have been introduced in wild ecosystems around the world to provide food or leisure, deliberately or from farm escapes. Some of those introductions have had large ecological effects. The north American native rainbow trout ( Oncorhynchus mykiss Walbaum, 1792) is one of the most widely farmed fish species in the world. It was first introduced in Spain in the late 19th century for sport fishing (Elvira 1995) and nowadays is used there for both fishing and aquaculture. On the other hand, the European native brown trout ( Salmo trutta L.) is catalogued as vulnerable in Spain. Detecting native and invasive fish populations in ecosystem monitoring is crucial, but it may be difficult from conventional sampling methods such as electrofishing. These techniques encompass some mortality, thus are not adequate for some ecosystems as the case of protected areas. Environmental DNA (eDNA) analysis is a sensitive and non-invasive method that can be especially useful for rare and low-density species detection and inventory in water bodies. In this study we employed two eDNA based methods (qPCR and nested PCR-RFLP) to detect salmonid species from mountain streams within a protected area, The Biosphere Reserve and Natural Park of Redes (Upper Nalón Basin, Asturias, Northern Spain), where brown trout is the only native salmonid. We also measured some habitat variables to see how appropriate for salmonids the area is. The sampling area is located upstream impassable dams and contains one rainbow trout fish farm. Employing qPCR methodology, brown trout eDNA was detected in all the nine sampling sites surveyed, while nested PCR-RFLP method failed to detect it in two sampling points. Rainbow trout eDNA was detected with both techniques at all sites in the Nalón River' (n1, n2 and n3). Salmonid habitat units and water quality were high from the area studied. In this study, a high quantity of rainbow trout eDNA was found upstream and downstream of a fish farm located inside a Biosphere Reserve. Unreported escapes from the fish farm are a likely explanation of these results. Since salmonid habitat is abundant and the water quality high, the establishment of rainbow trout populations would be favored should escapes occur. Environmental DNA has here proved to be a valuable tool for species detection in freshwater environments, and the probe-based qPCR highly sensitive technique for detection of scarce species. We would recommend this method for routine monitoring and early detection of introduced species within natural reserves.
DISTRIBUTION AND EXTENT OF NON-NATIVE FISH IN WESTERN STREAMS AND RIVERS
Introduced species can produce a variety of impacts on native assemblages and ecosystems. Reliable knowledge about the extent of non-native species should be a useful tool for effective management of fisheries and aquatic ecosystems. It is well known that many non-native fish s...
Sharing Tails®: A State-Wide Public Outreach Program Teaching Children about Native Arizona Fish
ERIC Educational Resources Information Center
Pacey, Carol A.; Marsh, Paul C.
2013-01-01
Limited public outreach programs about Arizona native fish exist and those that do are passive, fee-based, or Web-oriented, while others limit their geographic range. The program this article addresses sought to improve this situation with development of a state-wide outreach program with a goal to educate Arizona's children about native fish with…
Korman, Josh; Melis, Theodore S.
2011-01-01
The Lees Ferry reach of the Colorado River-a 16-mile segment from Glen Canyon Dam to the confluence with the Paria River-supports an important recreational rainbow trout (Oncorhynchus mykiss) fishery. In Grand Canyon, nonnative rainbow trout prey on and compete for habitat and food with native fish, such as the endangered humpback chub (Gila cypha). Experimental flow fluctuations from the dam during winter and spring 2003-5 dewatered and killed a high proportion of rainbow trout eggs in gravel spawning bars, but this mortality had no measurable effect on the abundance of juvenile fish. Flow fluctuations during summer months reduced growth of juvenile trout relative to steadier flows. A high-flow experiment in March 2008 increased both trout survival rates for early life stages and fish abundance. These findings demonstrate that Glen Canyon Dam operations directly affect the trout population in the Lees Ferry reach and could be used to regulate nonnative fish abundance to limit potential negative effects of trout on native fish in Grand Canyon.
Bronte, Charles R.; Evrard, Lori M.; Brown, William P.; Mayo, Kathleen R.; Edwards, Andrew J.
1998-01-01
Ruffe (Gymnocephalus cernuus) have been implicated in density declines of native species through egg predation and competition for food in some European waters where they were introduced. Density estimates for ruffe and principal native fishes in the St. Louis River estuary (western Lake Superior) were developed for 1989 to 1996 to measure changes in the fish community in response to an unintentional introduction of ruffe. During the study, ruffe density increased and the densities of several native species decreased. The reductions of native stocks to the natural population dynamics of the same species from Chequamegon Bay, Lake Superior (an area with very few ruffe) were developed, where there was a 24-year record of density. Using these data, short- and long-term variations in catch and correlations among species within years were compared, and species-specific distributions were developed of observed trends in abundance of native fishes in Chequamegon Bay indexed by the slopes of densities across years. From these distributions and our observed trend-line slopes from the St. Louis River, probabilities of measuring negative change at the magnitude observed in the St. Louis River were estimated. Compared with trends in Chequamegon Bay, there was a high probability of obtaining the negative slopes measured for most species, which suggests natural population dynamics could explain, the declines rather than interactions with ruffe. Variable recruitment, which was not related to ruffe density, and associated density-dependent changes in mortality likely were responsible for density declines of native species.
Early detection of non-native fishes using next-generation DNA sequencing of fish larvae
Our objective was to evaluate the use of fish larvae for early detection of non-native fishes, comparing traditional and molecular taxonomy based on next-generation DNA sequencing to investigate potential efficiencies. Our approach was to intensively sample a Great Lakes non-nati...
Laub, Brian G.; Thiede, Gary P.; Macfarlane, William W.; Budy, Phaedra
2018-01-01
We explored the conservation potential of tributaries in the upper Colorado River basin by modeling native fish species richness as a function of river discharge, temperature, barrier‐free length, and distance to nearest free‐flowing main‐stem section. We investigated a historic period prior to large‐scale water development and a contemporary period. In the historic period, species richness was log‐linearly correlated to variables capturing flow magnitude, particularly mean annual discharge. In the contemporary period, the log‐linear relationship between discharge and species richness was still evident but weaker. Tributaries with lower average temperature and separated from free‐flowing main‐stem sections often had fewer native species compared to tributaries with similar discharge but with warmer temperature and directly connected to free‐flowing main stems. Thus, tributaries containing only a small proportion of main‐stem discharge, especially those at lower elevations with warmer temperatures and connected to free‐flowing main stems, can support a relatively high species richness. Tributaries can help maintain viable populations by providing ecological processes disrupted on large regulated rivers, such as natural flow and temperature regimes, and may present unique conservation opportunities. Efforts to improve fish passage, secure environmental flows, and restore habitat in these tributaries could greatly contribute to conservation of native fish richness throughout the watershed.
Dispersal and selection mediate hybridization between a native and invasive species
Kovach, Ryan P.; Muhlfeld, Clint C.; Boyer, Matthew C.; Lowe, Winsor H.; Allendorf, Fred W.; Luikart, Gordon
2015-01-01
Hybridization between native and non-native species has serious biological consequences, but our understanding of how dispersal and selection interact to influence invasive hybridization is limited. Here, we document the spread of genetic introgression between a native (Oncorhynchus clarkii) and invasive (Oncorhynchus mykiss) trout, and identify the mechanisms influencing genetic admixture. In two populations inhabiting contrasting environments, non-native admixture increased rapidly from 1984 to 2007 and was driven by surprisingly consistent processes. Individual admixture was related to two phenotypic traits associated with fitness: size at spawning and age of juvenile emigration. Fish with higher non-native admixture were larger and tended to emigrate at a younger age—relationships that are expected to confer fitness advantages to hybrid individuals. However, strong selection against non-native admixture was evident across streams and cohorts (mean selection coefficient against genotypes with non-native alleles (s) ¼ 0.60; s.e. ¼ 0.10). Nevertheless, hybridization was promoted in both streams by the continuous immigration of individuals with high levels of non-native admixture from other hybrid source populations. Thus, antagonistic relationships between dispersal and selection are mediating invasive hybridization between these fish, emphasizing that data on dispersal and natural selection are needed to fully understand the dynamics of introgression between native and non-native species. .
Homogenization patterns of the world’s freshwater fish faunas
Villéger, Sébastien; Blanchet, Simon; Beauchard, Olivier; Oberdorff, Thierry; Brosse, Sébastien
2011-01-01
The world is currently undergoing an unprecedented decline in biodiversity, which is mainly attributable to human activities. For instance, nonnative species introduction, combined with the extirpation of native species, affects biodiversity patterns, notably by increasing the similarity among species assemblages. This biodiversity change, called taxonomic homogenization, has rarely been assessed at the world scale. Here, we fill this gap by assessing the current homogenization status of one of the most diverse vertebrate groups (i.e., freshwater fishes) at global and regional scales. We demonstrate that current homogenization of the freshwater fish faunas is still low at the world scale (0.5%) but reaches substantial levels (up to 10%) in some highly invaded river basins from the Nearctic and Palearctic realms. In these realms experiencing high changes, nonnative species introductions rather than native species extirpations drive taxonomic homogenization. Our results suggest that the “Homogocene era” is not yet the case for freshwater fish fauna at the worldwide scale. However, the distressingly high level of homogenization noted for some biogeographical realms stresses the need for further understanding of the ecological consequences of homogenization processes. PMID:22025692
Homogenization patterns of the world's freshwater fish faunas.
Villéger, Sébastien; Blanchet, Simon; Beauchard, Olivier; Oberdorff, Thierry; Brosse, Sébastien
2011-11-01
The world is currently undergoing an unprecedented decline in biodiversity, which is mainly attributable to human activities. For instance, nonnative species introduction, combined with the extirpation of native species, affects biodiversity patterns, notably by increasing the similarity among species assemblages. This biodiversity change, called taxonomic homogenization, has rarely been assessed at the world scale. Here, we fill this gap by assessing the current homogenization status of one of the most diverse vertebrate groups (i.e., freshwater fishes) at global and regional scales. We demonstrate that current homogenization of the freshwater fish faunas is still low at the world scale (0.5%) but reaches substantial levels (up to 10%) in some highly invaded river basins from the Nearctic and Palearctic realms. In these realms experiencing high changes, nonnative species introductions rather than native species extirpations drive taxonomic homogenization. Our results suggest that the "Homogocene era" is not yet the case for freshwater fish fauna at the worldwide scale. However, the distressingly high level of homogenization noted for some biogeographical realms stresses the need for further understanding of the ecological consequences of homogenization processes.
Status of native fishes in the western United States and issues for fire and fuels management
Bruce Rieman; Danny Lee; Dave Burns; Robert Gresswell; Michael Young; Rick Stowell; John Rinne; Philip Howell
2003-01-01
Conservation of native fishes and changing patterns in wildfire and fuels are defining challenges for managers of forested landscapes in the western United States. Many species and populations of native fishes have declined in recorded history and some now occur as isolated remnants of what once were larger more complex systems. Land management activities have been...
Fish trypsins: potential applications in biomedicine and prospects for production.
Jesús-de la Cruz, Kristal; Álvarez-González, Carlos Alfonso; Peña, Emyr; Morales-Contreras, José Antonio; Ávila-Fernández, Ángela
2018-04-01
In fishes, trypsins are adapted to different environmental conditions, and the biochemical and kinetic properties of a broad variety of native isoforms have been studied. Proteolytic enzymes remain in high demand in the detergent, food, and feed industries; however, our analysis of the literature showed that, in the last decade, some fish trypsins have been studied for the synthesis of industrial peptides and for specific biomedical uses as antipathogenic agents against viruses and bacteria, which have been recently patented. In addition, innovative strategies of trypsin administration have been studied to ensure that trypsins retain their properties until they exert their action. Biomedical uses require the production of high-quality enzymes. In this context, the production of recombinant trypsins is an alternative. For this purpose, E. coli -based systems have been tested for the production of fish trypsins; however, P. pastoris -based systems also seem to show great potential in the production of fish trypsins with higher production quality. On the other hand, there is a lack of information regarding the specific structures, biochemical and kinetic properties, and characteristics of trypsins produced using heterologous systems. This review describes the potential uses of fish trypsins in biomedicine and the enzymatic and structural properties of native and recombinant fish trypsins obtained to date, outlining some prospects for their study.
Brown trout and food web interactions in a Minnesota stream
Zimmerman, J.K.H.; Vondracek, B.
2007-01-01
1. We examined indirect, community-level interactions in a stream that contained non-native brown trout (Salmo trutta Linnaeus), native brook trout (Salvelinus fontinalis Mitchill) and native slimy sculpin (Cottus cognatus Richardson). Our objectives were to examine benthic invertebrate composition and prey selection of fishes (measured by total invertebrate dry mass, dry mass of individual invertebrate taxa and relative proportion of invertebrate taxa in the benthos and diet) among treatments (no fish, juvenile brook trout alone, juvenile brown trout alone, sculpin with brook trout and sculpin with brown trout). 2. We assigned treatments to 1 m2 enclosures/exclosures placed in riffles in Valley Creek, Minnesota, and conducted six experimental trials. We used three designs of fish densities (addition of trout to a constant number of sculpin with unequal numbers of trout and sculpin; addition of trout to a constant number of sculpin with equal numbers of trout and sculpin; and replacement of half the sculpin with an equal number of trout) to investigate the relative strength of interspecific versus intraspecific interactions. 3. Presence of fish (all three species, alone or in combined-species treatments) was not associated with changes in total dry mass of benthic invertebrates or shifts in relative abundance of benthic invertebrate taxa, regardless of fish density design. 4. Brook trout and sculpin diets did not change when each species was alone compared with treatments of both species together. Likewise, we did not find evidence for shifts in brown trout or sculpin diets when each species was alone or together. 5. We suggest that native brook trout and non-native brown trout fill similar niches in Valley Creek. We did not find evidence that either species had an effect on stream communities, potentially due to high invertebrate productivity in Valley Creek. ?? 2007 Blackwell Publishing Ltd.
Yavno, Stan; Rooke, Anna C; Fox, Michael G
2014-06-01
Non-indigenous species are oftentimes exposed to ecosystems with unfamiliar species, and organisms that exhibit a high degree of phenotypic plasticity may be better able to contend with the novel competitors that they may encounter during range expansion. In this study, differences in morphological plasticity were investigated using young-of-year pumpkinseed sunfish (Lepomis gibbosus) from native North American and non-native European populations. Two Canadian populations, isolated from bluegill sunfish (L. macrochirus) since the last glaciation, and two Spanish populations, isolated from bluegill since their introduction in Europe, were reared in a common environment using artificial enclosures. Fish were subjected to allopatric (without bluegill) or sympatric (with bluegill) conditions, and differences in plasticity were tested through a MANOVA of discriminant function scores. All pumpkinseed populations exhibited dietary shifts towards more benthivorous prey when held with bluegill. Differences between North American and European populations were observed in body dimensions, gill raker length and pelvic fin position. Sympatric treatments induced an increase in body width and a decrease in caudal peduncle length in native fish; non-native fish exhibited longer caudal peduncle lengths when held in sympatry with bluegill. Overall, phenotypic plasticity influenced morphological divergence less than genetic factors, regardless of population. Contrary to predictions, pumpkinseeds from Europe exhibited lower levels of phenotypic plasticity than Canadian populations, suggesting that European pumpkinseeds are more canalized than their North American counterparts.
NASA Astrophysics Data System (ADS)
Yavno, Stan; Rooke, Anna C.; Fox, Michael G.
2014-06-01
Non-indigenous species are oftentimes exposed to ecosystems with unfamiliar species, and organisms that exhibit a high degree of phenotypic plasticity may be better able to contend with the novel competitors that they may encounter during range expansion. In this study, differences in morphological plasticity were investigated using young-of-year pumpkinseed sunfish ( Lepomis gibbosus) from native North American and non-native European populations. Two Canadian populations, isolated from bluegill sunfish ( L. macrochirus) since the last glaciation, and two Spanish populations, isolated from bluegill since their introduction in Europe, were reared in a common environment using artificial enclosures. Fish were subjected to allopatric (without bluegill) or sympatric (with bluegill) conditions, and differences in plasticity were tested through a MANOVA of discriminant function scores. All pumpkinseed populations exhibited dietary shifts towards more benthivorous prey when held with bluegill. Differences between North American and European populations were observed in body dimensions, gill raker length and pelvic fin position. Sympatric treatments induced an increase in body width and a decrease in caudal peduncle length in native fish; non-native fish exhibited longer caudal peduncle lengths when held in sympatry with bluegill. Overall, phenotypic plasticity influenced morphological divergence less than genetic factors, regardless of population. Contrary to predictions, pumpkinseeds from Europe exhibited lower levels of phenotypic plasticity than Canadian populations, suggesting that European pumpkinseeds are more canalized than their North American counterparts.
Jason B. Dunham; Michael K. Young; Robert E. Gresswell; Bruce E. Rieman
2003-01-01
Our limited understanding of the short and long-term effects of fire on fish contributes to considerable uncertainty in assessments of the risks and benefits of fire management alternatives. A primary concern among the many potential effects of fire is the effects of fire and fire management on persistence of native fish populations. Limited evidence suggests...
Lake Ontario benthic prey fish assessment, 2016
Weidel, Brian C.; Walsh, Maureen; Holden, Jeremy P.; Connerton, Michael J.
2017-01-01
Benthic prey fishes are a critical component of the Lake Ontario food web, serving as energy vectors from benthic invertebrates to native and introduced piscivores. Beginning in 1978, Lake Ontario benthic prey fishes were assessed using bottom trawls collected from the lake’s south shore (depth range: 8 – 150 m). Historically, the survey targeted the then dominant species, Slimy Sculpin, however in 2015, the Benthic Prey Fish Survey was cooperatively expanded to a whole-lake survey, to address resource management information needs related to Round Goby, Deepwater Sculpin, and nearshore native fishes. In 2016, 142 trawls were collected at 18 transects, and spanned depths from 6 – 225 m. Trawl catches indicated the benthic and demersal prey fish community was dominated by Round Goby, however the proportional importance of native Deepwater Sculpin is increasing. Species-specific assessments found lake-wide Round Goby density (~600 fish per hectare) was slightly lower in 2016 relative to 2015. Deepwater Sculpin density has generally increased since 2004. In 2016 their estimated density was greater than 100 fish per hectare. Slimy Sculpin density (15 fish/ha) was similar to the past 3 years. Catches of juvenile Slimy Sculpin continue to be low relative to historic catches and the timing of their decline coincides with the proliferation of Round Goby. Additionally, we found a strong negative relationship between trawl catches of Round Goby and near-shore native benthic and demersal fishes such as Trout-perch, Johnny Darter and Spottail Shiner. The introduction of Round Goby and the reappearance of native Deepwater Sculpin have shaped the Lake Ontario benthic prey fish community.
Mechanical suppression of northern pike (Esox lucius) populations in small Arizona reservoirs
Kuzmenko, Yuliya; Spesiviy, Timofy; Bonar, Scott A.
2010-01-01
Introduced populations of northern pike Esox lucius have provided angling opportunities in the western United States (McMahon and Bennett 1996). However, the northern pike is a voracious piscivore and its large size, high fecundity, and broad physiological tolerance make it capable of drastically altering ecosystems it invades (Marchetti et al. 2004). Indeed, predation by northern pike has been shown to significantly alter fish community structure and put native fishes at a higher extinction risk (He and Kitchell 1990, Findlay et al. 2000). Predation by northern pike is viewed as a significant threat to native stocks of salmonids in Washington, British Columbia, and California (McMahon and Bennett 1996, California Department of Fish and Game [CDFG] 2003).
Water withdrawals reduce native fish diversity across the sunbelt of the US
NASA Astrophysics Data System (ADS)
Sabo, J. L.; Bowling, L. C.; Roath, J.; Sinha, T.; Kominoski, J.; Fuller, P.
2012-12-01
Water withdrawals for urban, industrial and agricultural uses are known to have negative effects on freshwater biodiversity, but this conclusion is based largely on a small number of place based studies. In this talk we will present results from a continental scale analysis of water withdrawals on the species richness of native and non-native fishes in the coterminous US. To do this we compiled data from the USGS on water withdrawals and the species richness of non-native fishes. We obtained data on the native fish species richness from NatureServe's native fish database. We also compiled spatial data on cropland area and urban impervious surfaces. Finally, we used gridded estimates of streamflow from the Variable Infiltration Capacity model and a routing model to estimate streamflow (less upstream water withdrawal). We estimate the water stress index (WSI) as withdrawals standardized by streamflow (local and upstream deliveries) and use this as a metric of sustainability of human water use. All data were compiled at the spatial resolution of 8-digit hydrologic unit code hydrologic accounting units. Our key finding is that human water use (WSI)--and not impervious surfaces or cropland area--has a strong negative effect on native, but not non-native biodiversity in rivers. This result was robust across the US sunbelt but weaker across the coterminous US. Our result suggests that the effects of cities and farms on native freshwater fauna are outweighed by the upstream and cross-basin extraction of water to support these land uses.
Buckwalter, Joseph D.; Frimpong, Emmanuel A.; Angermeier, Paul L.; Barney, Jacob N.
2018-01-01
AimKnowledge of expanding and contracting ranges is critical for monitoring invasions and assessing conservation status, yet reliable data on distributional trends are lacking for most freshwater species. We developed a quantitative technique to detect the sign (expansion or contraction) and functional form of range‐size changes for freshwater species based on collections data, while accounting for possible biases due to variable collection effort. We applied this technique to quantify stream‐fish range expansions and contractions in a highly invaded river system.LocationUpper and middle New River (UMNR) basin, Appalachian Mountains, USA.MethodsWe compiled a 77‐year stream‐fish collections dataset partitioned into ten time periods. To account for variable collection effort among time periods, we aggregated the collections into 100 watersheds and expressed a species’ range size as detections per watershed (HUC) sampled (DPHS). We regressed DPHS against time by species and used an information‐theoretic approach to compare linear and nonlinear functional forms fitted to the data points and to classify each species as spreader, stable or decliner.ResultsWe analysed changes in range size for 74 UMNR fishes, including 35 native and 39 established introduced species. We classified the majority (51%) of introduced species as spreaders, compared to 31% of natives. An exponential functional form fits best for 84% of spreaders. Three natives were among the most rapid spreaders. All four decliners were New River natives.Main conclusionsOur DPHS‐based approach facilitated quantitative analyses of distributional trends for stream fishes based on collections data. Partitioning the dataset into multiple time periods allowed us to distinguish long‐term trends from population fluctuations and to examine nonlinear forms of spread. Our framework sets the stage for further study of drivers of stream‐fish invasions and declines in the UMNR and is widely transferable to other freshwater taxa and geographic regions.
Work, Thierry M.; Rameyer, Robert; Takata, Geraldine; Kent, Michael L.
2003-01-01
The bluestripe snapper, or taape, was introduced into Hawaii in the 1950s and has since become very abundant throughout the archipelago. As part of a health survey of reef fish in Hawaii, we necropsied 120 taape collected from various coastal areas south of Oahu and examined fish histology for extraintestinal organisms. Forty-seven percent of taape were infected with an apicomplexan protozoan compatible with a coccidian. Infection was evident mainly in the spleen and, less commonly, the kidney. Prevalence of this coccidian increased with size of fish, and we saw no significant pathology associated with the organism. Twenty-six percent of taape were also infected with an epitheliocystis-like organism that occurred mainly in the kidney and, less commonly, the spleen. In contrast to the coccidian, fish mounted a notable inflammatory response to the epitheliocystis-like organism, and this inflammation appeared to increase in severity with age. Prevalence of the epitheliocystis-like organism infection increased with age, but infection was not seen in fish greater than 26.5 cm fork length. The high prevalence of coccidial infection in introduced taape prompts the concern that these organisms, along with the epitheliocystis-like organism, have the potential to be transmitted to native reef fish. Given the impact of other introduced microbial organisms on native Hawaiian fauna, there is a clear need to assess whether protozoa and bacteria are endemic to Hawaii, and whether they negatively impact native reef fish that closely associate with taape.
Dodrill, Michael J.; Yackulic, Charles B.; Gerig, Brandon; Pine, William E.; Korman, Josh; Finch, Colton
2015-01-01
Many management actions in aquatic ecosystems are directed at restoring or improving specific habitats to benefit fish populations. In the Grand Canyon reach of the Colorado River, experimental flow operations as part of the Glen Canyon Dam Adaptive Management Program have been designed to restore sandbars and associated backwater habitats. Backwaters can have warmer water temperatures than other habitats, and native fish, including the federally endangered humpback chub Gila cypha, are frequently observed in backwaters, leading to a common perception that this habitat is critical for juvenile native fish conservation. However, it is unknown how fish densities in backwaters compare with that in other habitats or what proportion of juvenile fish populations reside in backwaters. Here, we develop and fit multi-species hierarchical models to estimate habitat-specific abundances and densities of juvenile humpback chub, bluehead suckerCatostomus discobolus, flannelmouth sucker Catostomus latipinnis and speckled dace Rhinichthys osculus in a portion of the Colorado River. Densities of all four native fish were greatest in backwater habitats in 2009 and 2010. However, backwaters are rare and ephemeral habitats, so they contain only a small portion of the overall population. For example, the total abundance of juvenile humpback chub in this study was much higher in talus than in backwater habitats. Moreover, when we extrapolated relative densities based on estimates of backwater prevalence directly after a controlled flood, the majority of juvenile humpback chub were still found outside of backwaters. This suggests that the role of controlled floods in influencing native fish population trends may be limited in this section of the Colorado River.
Howeth, Jennifer G.; Gantz, Crysta A.; Angermeier, Paul; Frimpong, Emmanuel A.; Hoff, Michael H.; Keller, Reuben P.; Mandrak, Nicholas E.; Marchetti, Michael P.; Olden, Julian D.; Romagosa, Christina M.; Lodge, David M.
2016-01-01
AimImpacts of non-native species have motivated development of risk assessment tools for identifying introduced species likely to become invasive. Here, we develop trait-based models for the establishment and impact stages of freshwater fish invasion, and use them to screen non-native species common in international trade. We also determine which species in the aquarium, biological supply, live bait, live food and water garden trades are likely to become invasive. Results are compared to historical patterns of non-native fish establishment to assess the relative importance over time of pathways in causing invasions.LocationLaurentian Great Lakes region.MethodsTrait-based classification trees for the establishment and impact stages of invasion were developed from data on freshwater fish species that established or failed to establish in the Great Lakes. Fishes in trade were determined from import data from Canadian and United States regulatory agencies, assigned to specific trades and screened through the developed models.ResultsClimate match between a species’ native range and the Great Lakes region predicted establishment success with 75–81% accuracy. Trophic guild and fecundity predicted potential harmful impacts of established non-native fishes with 75–83% accuracy. Screening outcomes suggest the water garden trade poses the greatest risk of introducing new invasive species, followed by the live food and aquarium trades. Analysis of historical patterns of introduction pathways demonstrates the increasing importance of these trades relative to other pathways. Comparisons among trades reveal that model predictions parallel historical patterns; all fishes previously introduced from the water garden trade have established. The live bait, biological supply, aquarium and live food trades have also contributed established non-native fishes.Main conclusionsOur models predict invasion risk of potential fish invaders to the Great Lakes region and could help managers prioritize efforts among species and pathways to minimize such risk. Similar approaches could be applied to other taxonomic groups and geographic regions.
Luiz, Tatiane Ferraz; Velludo, Marcela Roquetti; Peret, Alberto Carvalho; Rodrigues Filho, Jorge Luiz; Peret, André Moldenhauer
2011-06-01
The Blue Peacock Bass (Cichla piquiti), native to the Tocantins-Araguaia river basin of the Amazon system, was introduced into the basin of the Paranaíba River, Paraná River system. Cachoeira Dourada reservoir is one of a series of dams on the Paranaíba River in central Brazil, where this fish has become established. A study of its feeding spectrum, combined with information about its reproductive characteristics and population structure, would enable the current state of this species in the reservoir to be assessed and might provide useful data for the management of other species native to this habitat. This study showed that the peacock bass has no predators or natural competitors in the reservoir and that reproduces continuously, with high reproductive rates, and has a smaller median length at first maturity (L50) than other species of Cichla. Its successful establishment in habitats strongly affected by human activity should cause changes in the whole structure of the local fish communities. Nonetheless, in this reservoir, there appears to be some sharing of the functions of this species with native carnivorous fish, a situation that may be sustained by the presence of a wide variety of foraging fish.
Sikkel, Paul C.; Tuttle, Lillian J.; Cure, Katherine; Coile, Ann Marie; Hixon, Mark A.
2014-01-01
Escape from parasites in their native range is one of many mechanisms that can contribute to the success of an invasive species. Gnathiid isopods are blood-feeding ectoparasites that infest a wide range of fish hosts, mostly in coral reef habitats. They are ecologically similar to terrestrial ticks, with the ability to transmit blood-borne parasites and cause damage or even death to heavily infected hosts. Therefore, being highly resistant or highly susceptible to gnathiids can have significant fitness consequences for reef-associated fishes. Indo-Pacific red lionfish (Pterois volitans) have invaded coastal habitats of the western tropical and subtropical Atlantic and Caribbean regions. We assessed the susceptibility of red lionfish to parasitic gnathiid isopods in both their native Pacific and introduced Atlantic ranges via experimental field studies during which lionfish and other, ecologically-similar reef fishes were caged and exposed to gnathiid infestation on shallow coral reefs. Lionfish in both ranges had very few gnathiids when compared with other species, suggesting that lionfish are not highly susceptible to infestation by generalist ectoparasitic gnathiids. While this pattern implies that release from gnathiid infestation is unlikely to contribute to the success of lionfish as invaders, it does suggest that in environments with high gnathiid densities, lionfish may have an advantage over species that are more susceptible to gnathiids. Also, because lionfish are not completely resistant to gnathiids, our results suggest that lionfish could possibly have transported blood parasites between their native Pacific and invaded Atlantic ranges. PMID:24796701
Sikkel, Paul C; Tuttle, Lillian J; Cure, Katherine; Coile, Ann Marie; Hixon, Mark A
2014-01-01
Escape from parasites in their native range is one of many mechanisms that can contribute to the success of an invasive species. Gnathiid isopods are blood-feeding ectoparasites that infest a wide range of fish hosts, mostly in coral reef habitats. They are ecologically similar to terrestrial ticks, with the ability to transmit blood-borne parasites and cause damage or even death to heavily infected hosts. Therefore, being highly resistant or highly susceptible to gnathiids can have significant fitness consequences for reef-associated fishes. Indo-Pacific red lionfish (Pterois volitans) have invaded coastal habitats of the western tropical and subtropical Atlantic and Caribbean regions. We assessed the susceptibility of red lionfish to parasitic gnathiid isopods in both their native Pacific and introduced Atlantic ranges via experimental field studies during which lionfish and other, ecologically-similar reef fishes were caged and exposed to gnathiid infestation on shallow coral reefs. Lionfish in both ranges had very few gnathiids when compared with other species, suggesting that lionfish are not highly susceptible to infestation by generalist ectoparasitic gnathiids. While this pattern implies that release from gnathiid infestation is unlikely to contribute to the success of lionfish as invaders, it does suggest that in environments with high gnathiid densities, lionfish may have an advantage over species that are more susceptible to gnathiids. Also, because lionfish are not completely resistant to gnathiids, our results suggest that lionfish could possibly have transported blood parasites between their native Pacific and invaded Atlantic ranges.
Environmental DNA for freshwater fish monitoring: insights for conservation within a protected area
Sandin, Miguel M.; Beaulieu, Paul G.; Clusa, Laura; Martinez, Jose L.; Ardura, Alba; García-Vázquez, Eva
2018-01-01
Background Many fish species have been introduced in wild ecosystems around the world to provide food or leisure, deliberately or from farm escapes. Some of those introductions have had large ecological effects. The north American native rainbow trout (Oncorhynchus mykiss Walbaum, 1792) is one of the most widely farmed fish species in the world. It was first introduced in Spain in the late 19th century for sport fishing (Elvira 1995) and nowadays is used there for both fishing and aquaculture. On the other hand, the European native brown trout (Salmo trutta L.) is catalogued as vulnerable in Spain. Detecting native and invasive fish populations in ecosystem monitoring is crucial, but it may be difficult from conventional sampling methods such as electrofishing. These techniques encompass some mortality, thus are not adequate for some ecosystems as the case of protected areas. Environmental DNA (eDNA) analysis is a sensitive and non-invasive method that can be especially useful for rare and low-density species detection and inventory in water bodies. Methods In this study we employed two eDNA based methods (qPCR and nested PCR-RFLP) to detect salmonid species from mountain streams within a protected area, The Biosphere Reserve and Natural Park of Redes (Upper Nalón Basin, Asturias, Northern Spain), where brown trout is the only native salmonid. We also measured some habitat variables to see how appropriate for salmonids the area is. The sampling area is located upstream impassable dams and contains one rainbow trout fish farm. Results Employing qPCR methodology, brown trout eDNA was detected in all the nine sampling sites surveyed, while nested PCR-RFLP method failed to detect it in two sampling points. Rainbow trout eDNA was detected with both techniques at all sites in the Nalón River’ (n1, n2 and n3). Salmonid habitat units and water quality were high from the area studied. Discussion In this study, a high quantity of rainbow trout eDNA was found upstream and downstream of a fish farm located inside a Biosphere Reserve. Unreported escapes from the fish farm are a likely explanation of these results. Since salmonid habitat is abundant and the water quality high, the establishment of rainbow trout populations would be favored should escapes occur. Environmental DNA has here proved to be a valuable tool for species detection in freshwater environments, and the probe-based qPCR highly sensitive technique for detection of scarce species. We would recommend this method for routine monitoring and early detection of introduced species within natural reserves. PMID:29527421
Native fish conservation areas: A vision for large-scale conservation of native fish communities
Williams, Jack E.; Williams, Richard N.; Thurow, Russell F.; Elwell, Leah; Philipp, David P.; Harris, Fred A.; Kershner, Jeffrey L.; Martinez, Patrick J.; Miller, Dirk; Reeves, Gordon H.; Frissell, Christopher A.; Sedell, James R.
2011-01-01
The status of freshwater fishes continues to decline despite substantial conservation efforts to reverse this trend and recover threatened and endangered aquatic species. Lack of success is partially due to working at smaller spatial scales and focusing on habitats and species that are already degraded. Protecting entire watersheds and aquatic communities, which we term "native fish conservation areas" (NFCAs), would complement existing conservation efforts by protecting intact aquatic communities while allowing compatible uses. Four critical elements need to be met within a NFCA: (1) maintain processes that create habitat complexity, diversity, and connectivity; (2) nurture all of the life history stages of the fishes being protected; (3) include a long-term enough watershed to provide long-term persistence of native fish populations; and (4) provide management that is sustainable over time. We describe how a network of protected watersheds could be created that would anchor aquatic conservation needs in river basins across the country.
Invasive fishes generate biogeochemical hotspots in a nutrient-limited system.
Capps, Krista A; Flecker, Alexander S
2013-01-01
Fishes can play important functional roles in the nutrient dynamics of freshwater systems. Aggregating fishes have the potential to generate areas of increased biogeochemical activity, or hotspots, in streams and rivers. Many of the studies documenting the functional role of fishes in nutrient dynamics have focused on native fish species; however, introduced fishes may restructure nutrient storage and cycling freshwater systems as they can attain high population densities in novel environments. The purpose of this study was to examine the impact of a non-native catfish (Loricariidae: Pterygoplichthys) on nitrogen and phosphorus remineralization and estimate whether large aggregations of these fish generate measurable biogeochemical hotspots within nutrient-limited ecosystems. Loricariids formed large aggregations during daylight hours and dispersed throughout the stream during evening hours to graze benthic habitats. Excretion rates of phosphorus were twice as great during nighttime hours when fishes were actively feeding; however, there was no diel pattern in nitrogen excretion rates. Our results indicate that spatially heterogeneous aggregations of loricariids can significantly elevate dissolved nutrient concentrations via excretion relative to ambient nitrogen and phosphorus concentrations during daylight hours, creating biogeochemical hotspots and potentially altering nutrient dynamics in invaded systems.
Invasive Fishes Generate Biogeochemical Hotspots in a Nutrient-Limited System
Capps, Krista A.; Flecker, Alexander S.
2013-01-01
Fishes can play important functional roles in the nutrient dynamics of freshwater systems. Aggregating fishes have the potential to generate areas of increased biogeochemical activity, or hotspots, in streams and rivers. Many of the studies documenting the functional role of fishes in nutrient dynamics have focused on native fish species; however, introduced fishes may restructure nutrient storage and cycling freshwater systems as they can attain high population densities in novel environments. The purpose of this study was to examine the impact of a non-native catfish (Loricariidae: Pterygoplichthys) on nitrogen and phosphorus remineralization and estimate whether large aggregations of these fish generate measurable biogeochemical hotspots within nutrient-limited ecosystems. Loricariids formed large aggregations during daylight hours and dispersed throughout the stream during evening hours to graze benthic habitats. Excretion rates of phosphorus were twice as great during nighttime hours when fishes were actively feeding; however, there was no diel pattern in nitrogen excretion rates. Our results indicate that spatially heterogeneous aggregations of loricariids can significantly elevate dissolved nutrient concentrations via excretion relative to ambient nitrogen and phosphorus concentrations during daylight hours, creating biogeochemical hotspots and potentially altering nutrient dynamics in invaded systems. PMID:23342083
Dispersal and selection mediate hybridization between a native and invasive species.
Kovach, Ryan P; Muhlfeld, Clint C; Boyer, Matthew C; Lowe, Winsor H; Allendorf, Fred W; Luikart, Gordon
2015-01-22
Hybridization between native and non-native species has serious biological consequences, but our understanding of how dispersal and selection interact to influence invasive hybridization is limited. Here, we document the spread of genetic introgression between a native (Oncorhynchus clarkii) and invasive (Oncorhynchus mykiss) trout, and identify the mechanisms influencing genetic admixture. In two populations inhabiting contrasting environments, non-native admixture increased rapidly from 1984 to 2007 and was driven by surprisingly consistent processes. Individual admixture was related to two phenotypic traits associated with fitness: size at spawning and age of juvenile emigration. Fish with higher non-native admixture were larger and tended to emigrate at a younger age--relationships that are expected to confer fitness advantages to hybrid individuals. However, strong selection against non-native admixture was evident across streams and cohorts (mean selection coefficient against genotypes with non-native alleles (s) = 0.60; s.e. = 0.10). Nevertheless, hybridization was promoted in both streams by the continuous immigration of individuals with high levels of non-native admixture from other hybrid source populations. Thus, antagonistic relationships between dispersal and selection are mediating invasive hybridization between these fish, emphasizing that data on dispersal and natural selection are needed to fully understand the dynamics of introgression between native and non-native species. © 2014 The Author(s) Published by the Royal Society. All rights reserved.
Almeida, David; Ribeiro, Filipe; Leunda, Pedro M; Vilizzi, Lorenzo; Copp, Gordon H
2013-08-01
Risk assessments are crucial for identifying and mitigating impacts from biological invasions. The Fish Invasiveness Scoring Kit (FISK) is a risk identification (screening) tool for freshwater fishes consisting of two subject areas: biogeography/history and biology/ecology. According to the outcomes, species can be classified under particular risk categories. The aim of this study was to apply FISK to the Iberian Peninsula, a Mediterranean climate region highly important for freshwater fish conservation due to a high level of endemism. In total, 89 fish species were assessed by three independent assessors. Results from receiver operating characteristic analysis showed that FISK can discriminate reliably between noninvasive and invasive fishes for Iberia, with a threshold of 20.25, similar to those obtained in several regions around the world. Based on mean scores, no species was categorized as "low risk," 50 species as "medium risk," 17 as "moderately high risk," 11 as "high risk," and 11 as "very high risk." The highest scoring species was goldfish Carassius auratus. Mean certainty in response was above the category "mostly certain," ranging from tinfoil barb Barbonymus schwanenfeldii with the lowest certainty to eastern mosquitofish Gambusia holbrooki with the highest level. Pair-wise comparison showed significant differences between one assessor and the other two on mean certainty, with these two assessors showing a high coincidence rate for the species categorization. Overall, the results suggest that FISK is a useful and viable tool for assessing risks posed by non-native fish in the Iberian Peninsula and contributes to a "watch list" in this region. © 2013 Crown copyright This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.
Snakeheads (Pisces, Channidae): A biological synopsis and risk assessment
Courtenay, Walter R.; Williams, James D.
2004-01-01
Snakeheads (family Channidae) are airbreathing freshwater fishes containing two genera, Channa with 26 species native to Asia, Malaysia, and Indonesia; and Parachanna with 3 species native to tropical Africa. Some snakeheads are small, reaching about 17 centimeters, but most are much larger, the largest reported to be 1.8 meters in length. All are considered thrust predators with most being piscivorous as adults. A few of the smaller snakeheads and colorful juveniles of some larger ones have been available to hobbyists through the aquarium fish trade. Several species are highly valued as food fishes within parts of their native ranges, especially in Asia where they are an important part of capture fisheries and aquaculture. Because of these uses by humans, introductions far beyond native ranges have occurred. One Asian snakehead has been established in Oahu, Hawaii, since before 1900. Another species was discovered established in southeastern Florida in 2000, and a third in a pond in Maryland in 2002. Others have been captured from natural waters of the United States without evidence of reproduction and likely represent released aquarium fishes. That snakeheads at or near sexual maturity were being sold alive in ethnic food markets raised fears that they could be introduced into novel waters. These concerns led to this study on the biology of snakeheads. A risk assessment is included that examines environmental and related aspects of snakehead introductions.
Tropical fish community does not recover 45 years after predator introduction.
Sharpe, D M T; De León, L F; González, R; Torchin, M E
2017-02-01
Predation is considered to be an important factor structuring natural communities. However, it is often difficult to determine how it may influence long-term, broad-scale, diversity patterns, particularly in diverse tropical systems. Biological introductions can provide powerful insight to test the sustained consequences of predation in natural communities, if pre-introduction data are available. Half a century ago, Zaret and Paine demonstrated strong and immediate community-level effects following the introduction of a novel apex predator (peacock bass, Cichla monoculus) into Lake Gatun, Panama. To test for long-term changes associated with this predator introduction, we followed up on their classic study by replicating historical sampling methods and examining changes in the littoral fish community at two sites in Lake Gatun 45 years post-introduction. To broaden our inference, we complemented this temporal comparison with a spatial analysis, wherein we compared the fish communities from two lakes with and one lake without peacock bass. Comparisons with historical data revealed that the peacock bass remains the most abundant predator in Lake Gatun. Furthermore, the collapse of the littoral prey community observed immediately following the invasion has been sustained over the past 45 years. The mean abundance of native littoral fish is now 96% lower than it was prior to the introduction. Diversity (rarefied species richness) declined by 64% post-introduction, and some native species appear to have been locally extirpated. We observed a similar pattern across invaded and uninvaded lakes: the mean abundance of native fishes was 5-40 times lower in lakes with (Gatun, Alajuela) relative to the lake without peacock bass (Bayano). In particular, small-bodied native fishes (Characidae, Peociliidae), which are common prey of the peacock bass, were more than two orders of magnitude (307 times) less abundant in Gatun and one order of magnitude (28 times) less abundant in Alajuela than in Bayano. However, total native fish diversity did not differ significantly across lakes, suggesting that while many native species have declined in abundance, few have been completely extirpated. Introduced predators can have strong effects on community structure and functional diversity, even in highly diverse tropical communities, and these effects can persist over multiple decades. © 2016 by the Ecological Society of America.
Karen Pope; Erin C. Hannelly
2013-01-01
Introduced fish reduce the abundance and diversity of native aquatic fauna, but the effect can be reduced in complex habitats. We manipulated fish populations in forested mountain lakes to determine whether or not fish affected benthic macroinvertebrate composition across lakes with differing habitat complexity. We compared abundance, biomass, body-length, and...
Rose, Brien P.; Hansen, Gabriel S.; Mesa, Matthew G.
2011-01-01
In response to these recent concerns about the potential predatory impact of non-native piscivores on salmon survival, the Bonneville Power Administration (BPA) and the Columbia Basin Fish and Wildlife Authority (CBFWA) co-hosted a workshop to address predation on juvenile salmonids in the CRB by non-native fish (Halton 2008). The purpose of the workshop was to review, evaluate, and develop strategies to reduce predation by non-native fishes on juvenile salmonids. In the end, discussion at the workshop and at subsequent meetings considered two potential ideas to reduce predation by non-native fish on juvenile salmonids; (1) understanding the role of juvenile American shad Alosa sapidissima in the diet of non-native predators in the fall; and (2) the effects of localized, intense reductions of smallmouth bass in areas of particularly high salmonid predation. In this report, we describe initial efforts to understand the influence of juvenile American shad as a prey item for introduced predators in the middle Columbia River. Our first objective, addressed in Chapter 1, was to evaluate the efficacy of nonlethal methods to describe the physiological condition of smallmouth bass, walleye, and channel catfish from late summer through late fall. Such information will be used to understand the contribution of juvenile American shad to the energy reserves of predaceous fish prior to winter. In Chapter 2, we describe the results of some limited sampling to document the food habits of smallmouth bass, walleye, and channel catfish in three reservoirs of the middle Columbia River during late fall. Collectively, we hope to increase our understanding of the contribution of juvenile American shad to the diets of introduced predators and the contribution of this diet to their energy reserves, growth, and perhaps over-winter survival. Managers should be able to use this information for deciding whether to control the population of American shad in the CRB or for managing introduced predaceous fish in the CRB.
Peacock, Mary M; Gustin, Mae S; Kirchoff, Veronica S; Robinson, Morgan L; Hekkala, Evon; Pizzarro-Barraza, Claudia; Loux, Tim
2016-09-01
In-stream structures are recognized as significant impediments to movement for freshwater fishes. Apex predators such as salmonids have been the focus of much research on the impacts of such barriers to population dynamics and population viability however much less research has focused on native fishes, where in-stream structures may have a greater impact on long term population viability of these smaller, less mobile species. Patterns of genetic structure on a riverscape can provide information on which structures represent real barriers to movement for fish species and under what specific flow conditions. Here we characterize the impact of 41 dam and diversion structures on movement dynamics under varying flow conditions for a suite of six native fishes found in the Truckee River of California and Nevada. Microsatellite loci were used to estimate total allelic diversity, effective population size and assess genetic population structure. Although there is spatial overlap among species within the river there are clear differences in species distributions within the watershed. Observed population genetic structure was associated with in-stream structures, but only under low flow conditions. High total discharge in 2006 allowed fish to move over potential barriers resulting in no observed population genetic structure for any species in 2007. The efficacy of in-stream structures to impede movement and isolate fish emerged only after multiple years of low flow conditions. Our results suggest that restricted movement of fish species, as a result of in-stream barriers, can be mitigated by flow management. However, as flow dynamics are likely to be altered under global climate change, fragmentation due to barriers could isolate stream fishes into small subpopulations susceptible to both demographic losses and losses of genetic variation. Copyright © 2016 Elsevier B.V. All rights reserved.
The Western Fisheries Research Center studies: threatened and endangered fishes
Parsley, M.; Scoppettone, G.G.; Shively, R.; Gadomski, D.; Becker, D.
2005-01-01
Within historical time, western native fish communities have faced increasing threats from habitat loss, invasive species, and pollution. It should come as no surprise that human development has greatly altered fish habitat in the west because of the importance of water for domestic, agricultural, and industrial uses, power generation, waste disposal, flood protection, and transportation. Fish that were adapted to natural cycles of river flow, lake levels, and water temperatures have been unable to adapt to the changes to these cycles caused by development, leading to the listing as threatened or endangered of 68 species of western native fishes. Rapid expansion of non-native fishes, aquatic plants, and invertebrates has increased competition for food and space while pollutants from past and present degrade our lakes, streams, and rivers.
Yard, Michael D.; Coggins,, Lewis G.; Baxter, Colden V.; Bennett, Glenn E.; Korman, Josh
2011-01-01
Introductions of nonnative salmonids, such as rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta, have affected native fishes worldwide in unforeseen and undesirable ways. Predation and other interactions with nonnative rainbow trout and brown trout have been hypothesized as contributing to the decline of native fishes (including the endangered humpback chub Gila cypha) in the Colorado River, Grand Canyon. A multiyear study was conducted to remove nonnative fish from a 15-km segment of the Colorado River near the Little Colorado River confluence. We evaluated how sediment, temperature, fish prey availability, and predator abundance influenced the incidence of piscivory (IP) by nonnative salmonids. Study objectives were addressed through spatial (upstream and downstream of the Little Colorado River confluence) and temporal (seasonal and annual) comparisons of prey availability and predator abundance. Data were then evaluated by modeling the quantity of fish prey ingested by trout during the first 2 years (2003–2004) of the mechanical removal period. Field effort resulted in the capture of 20,000 nonnative fish, of which 90% were salmonids. Results indicated that the brown trout IP was higher (8–70%) than the rainbow trout IP (0.5–3.3%); however, rainbow trout were 50 times more abundant than brown trout in the study area. We estimated that during the study period, over 30,000 fish (native and nonnative species combined) were consumed by rainbow trout (21,641 fish) and brown trout (11,797 fish). On average, rainbow trout and brown trout ingested 85% more native fish than nonnative fish in spite of the fact that native fish constituted less than 30% of the small fish available in the study area. Turbidity may mediate piscivory directly by reducing prey detection, but this effect was not apparent in our data, as rainbow trout IP was greater when suspended sediment levels (range = 5.9–20,000 mg/L) were higher.
SHAHI, Mehran; KAMRANI, Ehsan; SALEHI, Mehrdad; HABIBI, Reza; HANAFI-BOJD, Ahmad Ali
2015-01-01
Background: The widespread use of chemical insecticides, resistance in vectors and environmental problems, all have led to an increased interest in the use of biological agents in malaria control programs. The most important functional elements are the native fish. The aim of this study was to identify the native species of lavivorous fish in Rudan County, southern Iran, to introduce an effective species and to propose its’ implementation in the national malaria control program. Methods: This ecologically descriptive study was conducted during 2011–2012 using random sampling from different fish habitats of Rudan County. The shoals of fish were caught using fishing net. Fish samples were then identified in the Ichthyology lab, Department of Fisheries and the Environment, Hormozgan University. Results: Three species of larvivorous fish were identified as follows: Gambusia holbrooki, Aphaniusdispar dispar and Aphanius sp. The latter species has the most distribution in the study area and needs more morphological and molecular studies for identification at the species level. Conclusion: Two species of native fish, i.e., A. dispar and A. sp. with larvivorous potential live in the area. Further studies on their predatory property are recommended in order to apply this local potential against malaria vectors in the area. PMID:26744713
Aquatic assemblages of the highly urbanized Santa Ana River Basin, California
Brown, Larry R.; Burton, Carmen; Belitz, Kenneth
2005-01-01
We assessed the structure of periphyton, benthic macroinvertebrate, and fish assemblages and their associations with environmental variables at 17 sites on streams of the highly urbanized Santa Ana River basin in Southern California. All assemblages exhibited strong differences between highly urbanized sites in the valley and the least-impacted sites at the transition between the valley and undeveloped mountains. Results within the urbanized area differed among taxa. Periphyton assemblages were dominated by diatoms (>75% of total taxa). Periphyton assemblages within the urbanized area were not associated with any of the measured environmental variables, suggesting that structure of urban periphyton assemblages might be highly dependent on colonization dynamics. The number of Ephemeroptera, Trichoptera, and Plecoptera (EPT) taxa included in macroinvertebrate assemblages ranged from 0 to 6 at urbanized sites. Benthic macroinvertebrate assemblages had significant correlations with several environmental variables within the urban area, suggesting that stream size and permanence were important determinants of distribution among the species able to survive conditions in urban streams. Only 4 of 16 fish species collected were native to the drainage. Fish assemblages of urbanized sites included two native species, arroyo chub Gila orcuttii and Santa Ana sucker Catostomus santaanae, at sites that were intermediate in coefficient of variation of bank-full width, depth, bed substrate, and water temperature. Alien species dominated urbanized sites with lesser or greater values for these variables. These results suggest that urban streams can be structured to enhance populations of native fishes. Continued study of urban streams in the Santa Ana River basin and elsewhere will contribute to the basic understanding of ecological principles and help preserve the maximum ecological value of streams in highly urbanized areas.
R. A. Knapp; Kathleen R. Matthews
2000-01-01
Wilderness areas of the Sierra Nevada, California contain thousands of lakes and ponds, nearly all of which were historically fishless. After more than a century of fish stocking, introduced trout are now present in up to 80% of larger lakes. These nonnative fishes have had profound impacts on native fishes, amphibians, and invertebrates. Several of these native...
Non-native salmonids affect amphibian occupancy at multiple spatial scales
Pilliod, David S.; Hossack, Blake R.; Bahls, Peter F.; Bull, Evelyn L.; Corn, Paul Stephen; Hokit, Grant; Maxell, Bryce A.; Munger, James C.; Wyrick, Aimee
2010-01-01
Aim The introduction of non-native species into aquatic environments has been linked with local extinctions and altered distributions of native species. We investigated the effect of non-native salmonids on the occupancy of two native amphibians, the long-toed salamander (Ambystoma macrodactylum) and Columbia spotted frog (Rana luteiventris), across three spatial scales: water bodies, small catchments and large catchments. Location Mountain lakes at ≥ 1500 m elevation were surveyed across the northern Rocky Mountains, USA. Methods We surveyed 2267 water bodies for amphibian occupancy (based on evidence of reproduction) and fish presence between 1986 and 2002 and modelled the probability of amphibian occupancy at each spatial scale in relation to habitat availability and quality and fish presence. Results After accounting for habitat features, we estimated that A. macrodactylum was 2.3 times more likely to breed in fishless water bodies than in water bodies with fish. Ambystoma macrodactylum also was more likely to occupy small catchments where none of the water bodies contained fish than in catchments where at least one water body contained fish. However, the probability of salamander occupancy in small catchments was also influenced by habitat availability (i.e. the number of water bodies within a catchment) and suitability of remaining fishless water bodies. We found no relationship between fish presence and salamander occupancy at the large-catchment scale, probably because of increased habitat availability. In contrast to A. macrodactylum, we found no relationship between fish presence and R. luteiventris occupancy at any scale. Main conclusions Our results suggest that the negative effects of non-native salmonids can extend beyond the boundaries of individual water bodies and increase A. macrodactylum extinction risk at landscape scales. We suspect that niche overlap between non-native fish and A. macrodactylum at higher elevations in the northern Rocky Mountains may lead to extinction in catchments with limited suitable habitat.
NASA Astrophysics Data System (ADS)
McCleary, R. J.; Hassan, M. A.
2006-12-01
An automated procedure was developed to model spatial fish distributions within small streams in the Foothills of Alberta. Native fish populations and their habitats are susceptible to impacts arising from both industrial forestry and rapid development of petroleum resources in the region. Knowledge of fish distributions and the effects of industrial activities on their habitats is required to help conserve native fish populations. Resource selection function (RSF) models were used to explain presence/absence of fish in small streams. Target species were bull trout, rainbow trout and non-native brook trout. Using GIS, the drainage network was divided into reaches with uniform slope and drainage area and then polygons for each reach were created. Predictor variables described stream size, stream energy, climate and land-use. We identified a set of candidate models and selected the best model using a standard Akaike Information Criteria approach. The best models were validated with two external data sets. Drainage area and basin slope parameters were included in all best models. This finding emphasizes the importance of controlling for the energy dimension at the basin scale in investigations into the effects of land-use on aquatic resources in this transitional landscape between the mountains and plains. The best model for bull trout indicated a relation between the presence of artificial migration barriers in downstream areas and the extirpation of the species from headwater reaches. We produced reach-scale maps by species and summarized this information within all small catchments across the 12,000 km2 study area. These maps had included three categories based on predicted probability of capture for individual reaches. The high probability category had a 78 percent accuracy for correctly predicting both fish present and fish not-present reaches. Basin scale maps highlight specific watersheds likely to support both native bull trout and invasive brook trout, while reach-scale maps indicate specific reaches where interactions between these two species are likely to occur. With regional calibration, this automated modeling and mapping procedure could apply in headwater catchments throughout the Rocky Mountain Foothills and other areas where sporadic waterfalls or other natural migration barriers are not an important feature limiting fish distribution.
A conservation plan for native fishes of the Lower Colorado River
Minckley, W.L.; Marsh, P.C.; Deacon, J.E.; Dowling, T.E.; Hedrick, P.W.; Matthews, W.J.; Mueller, G.
2003-01-01
The native fish fauna of the lower Colorado River, in the western United States, includes four “big-river” fishes that are federally listed as endangered. Existing recovery implementation plans are inadequate for these critically imperiled species. We describe a realistic, proactive management program founded on demographic and genetic principles and crafted to avoid potential conflicts with nonnative sport fisheries. In this program, native species would breed and their progeny grow in isolated, protected, off-channel habitats in the absence of nonnative fishes. Panmictic adult populations would reside in the main channel and connected waters, exchanging reproductive adults and repatriated subadults with populations occupying isolated habitats. Implementation of the plan would greatly enhance recovery potential of the four listed fishes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Loranger, S.; Houde, L.; Schetagne, R.
1995-12-31
Hydro-Quebec is planning to build two hydroelectric reservoirs in the upper Saint-Maurice River, which would flood about 80% of the surrounding area. The methylmercury (MeHg) content in freshwater fish will therefore tend to increase during the first few years. This development will have a direct impact on the amount of MeHg that the actual users of this river section are exposed to. The objective of this study is to assess the consumption of local fish of these target groups using a Monte-Carlo approach. This study is part of a larger research project aimed at assessing human exposure and the healthmore » risks related to MeHg contamination in local fish. The fish consumption rate for recreational freshwater anglers was calculated using the duration of the average annual fishing trip, the average number of catches per species, the average fish weight per species exceeding a specific length of fish usually caught, and the edible portion of fish consumed. This rate was calculated for the native communities based on the total number of meals per year per species, the average fish weight per species, and the edible portion. Based on these calculations, average intake for sport fishermen is estimated at 6.9 g/day (sd = 6.4). This value is 5 to 25 times lower on average than for other North American native communities. However, it must be pointed out that the food habits of the native population were very similar to those of non-native populations; less than 30% of the food comes from traditional sources.« less
Ruppert, Jonathan L W; Docherty, Cassandra; Neufeld, Kenton; Hamilton, Kyle; MacPherson, Laura; Poesch, Mark S
2017-10-01
Prussian carp ( Carassius gibelio ) are one of the most noxious non-native species in Eurasia. Recently, Prussian carp, a non-native freshwater fish species, were genetically confirmed in Alberta, Canada and have been rapidly expanding their range in North America since establishment. Given their rapid range expansion, there is an increasing need to determine how Prussian carp may impact native species. We assessed the severity of the Prussian carp invasion by (i) determining their impact on fish communities, (ii) assessing their impact on benthic invertebrate communities, (iii) evaluating if Prussian carp alter abiotic conditions, and (iv) identifying where we find higher abundances of Prussian carp. When Prussian carp were established, we found significant changes to the fish community. Correspondingly, the degree of impact to benthic invertebrate communities was related to the stage of invasion (none, early or recent), where changes in fish communities were significantly concordant with changes in benthic invertebrate communities. Finally, we found that higher abundances of Prussian carp were significantly associated with lower abundances of a majority of native fish species. Altogether, using three lines of evidence, we determine that Prussian carp can have wide-ranging impacts on freshwater ecosystems in North America, pressing the need for management intervention.
Ruppert, Jonathan L. W.; Docherty, Cassandra; Neufeld, Kenton; Hamilton, Kyle; MacPherson, Laura
2017-01-01
Prussian carp (Carassius gibelio) are one of the most noxious non-native species in Eurasia. Recently, Prussian carp, a non-native freshwater fish species, were genetically confirmed in Alberta, Canada and have been rapidly expanding their range in North America since establishment. Given their rapid range expansion, there is an increasing need to determine how Prussian carp may impact native species. We assessed the severity of the Prussian carp invasion by (i) determining their impact on fish communities, (ii) assessing their impact on benthic invertebrate communities, (iii) evaluating if Prussian carp alter abiotic conditions, and (iv) identifying where we find higher abundances of Prussian carp. When Prussian carp were established, we found significant changes to the fish community. Correspondingly, the degree of impact to benthic invertebrate communities was related to the stage of invasion (none, early or recent), where changes in fish communities were significantly concordant with changes in benthic invertebrate communities. Finally, we found that higher abundances of Prussian carp were significantly associated with lower abundances of a majority of native fish species. Altogether, using three lines of evidence, we determine that Prussian carp can have wide-ranging impacts on freshwater ecosystems in North America, pressing the need for management intervention. PMID:29134062
Miller, Matthew P.; Lambert, Patrick M.; Hardy, Thomas B.
2014-01-01
Pah Tempe Springs discharge hot, saline, low dissolved-oxygen water to the Virgin River in southwestern Utah, which is transported downstream to Lake Mead and the Colorado River. The dissolved salts in the Virgin River negatively influence the suitability of this water for downstream agricultural, municipal, and industrial use. Therefore, various remediation scenarios to remove the salt load discharged from Pah Tempe Springs to the Virgin River are being considered. One concern about this load removal is the potential to impact the ecology of the Virgin River. Specifically, information is needed regarding possible impacts of Pah Tempe Springs remediation scenarios on the abundance, distribution, and survival of native fish in the Virgin River. Future efforts that aim to quantitatively assess how various remediation scenarios to reduce the load of dissolved salts from Pah Tempe Springs into the Virgin River may influence the abundance, distribution, and survival of native fish will require data on discharge, water quality, and native fish abundance. This report contains organized accessible discharge, water quality, and native fish abundance data sets from the Virgin River, documents the compilation of these data, and discusses approaches for quantifying relations between abiotic physical and chemical conditions, and fish abundance.
Adaptive Flow Management in Regulated Rivers: Successes and Challenges (Invited)
NASA Astrophysics Data System (ADS)
Robinson, C. T.; Melis, T. S.; Kennedy, T.; Korman, J.; Ortlepp, J.
2013-12-01
Experimental high flows are becoming common management actions in rivers affected by large dams. When implemented under clear objectives and goals, experimental flows provide opportunities for long-term ecological successes but also impose various ecological challenges as systems shift under environmental change or from human-related actions. We present case studies from long-term adaptive flow management programs on the River Spöl, Switzerland and the Colorado River, USA, both of which are regulated by high dams and flow through National Parks. The management goals in each system differ thus reflecting the different high flow practices implemented over time. Regulated flows in the Spöl reflect a compromise between hydropower needs and ecology (native brown trout fishery), whereas Glen Canyon Dam flows have mainly been directed towards maintenance of river beaches in Grand Canyon National Park with co-management of both nonnative rainbow trout in the tailwater immediately below the dam and downstream endangered native fish of Grand Canyon also an objective. Some 24 experimental floods have occurred on the Spöl over the last 13 years, resulting in a positive effect on the trout fishery and a zoobenthic assemblage having a more typical alpine stream composition. The system has experienced various shifts in assemblage composition over time with the last shift occurring 7 years after the initial floods. A major challenge occurred in spring 2013 with an accidental release of fine sediments from the reservoir behind Punt dal Gall Dam, causing high fish mortality and smothering of the river bottom. Results showed that the effect was pronounced near the dam and gradually lessened downriver to the lower reservoir. Zoobenthic assemblages displayed relatively high resistance to the event and some fish found refugia in the lower reservoir and larger side tributaries, thus projecting a faster recovery than initially thought. Below Glen Canyon dam, benefits to sandbars have been marginal since experimental constrained hydropower releases began in 1991 and controlled floods began in 1996 (7 have been released through 2012), while native fish populations have increased, although apparently not in response to flows. However, nonnative rainbow trout have been shown to increase in abundance repeatedly below Glen Canyon Dam in response to both controlled floods and more stable flows, both of which were originally proposed to benefit Grand Canyon beaches. Survival of trout fry following the 2008 spring flood was apparently tied to increased abundance of benthic invertebrates in the tailwater. Expansion of nonnative trout in response to high flows pose a potential threat to native fish downstream through competition for limited food and habitat, and through predation of juvenile native fish. Challenges are presented for each system in terms of flow implementation under hydropower needs (Spöl) and environmental change (Colorado). We close with perspectives on improving adaptive flow management actions in regulated rivers as learning-based, long-term ecological experiments.
Desired future condition: Fish habitat in southwestern riparian-stream habitats
John N. Rinne
1996-01-01
Riparian ecosystems in the southwestern United States provide valuable habitats for many living organisms including native fishes. An analysis of habitat components important to native fishes was made based on the literature, case histories, and unpublished and observational data. Results suggest a natural, surface water hydrograph and lack of introduced species of...
We reviewed the results of seven extensive and two reach-specific fish surveys conducted on the mainstem Willamette River between 1944 and 2006 to document changes in the summer distribution and species richness of non-native fishes through time and the relative abundances of the...
Critical role of seasonal tributaries for native fish and aquatic biota in the Sacramento River
NASA Astrophysics Data System (ADS)
Marchetti, M.
2016-12-01
We examined the ecology of seasonal tributaries in California in terms of native fishes and aquatic macroinvertebrates. This talk summarizes data from five individual studies. Studying juvenile Chinook growth using otolith microstructure we find that fish grow faster and larger in seasonal tributaries. In a four-year study on the abundance of native fish larvae in tributaries of the Sacramento River we find certain tributaries produce an order of magnitude more native fish larvae than nearby permanent streams. In a study comparing the distribution and abundance of aquatic macroinvertebrates in a seasonal tributary with a permanent stream we find the seasonal tributary contains unique taxa, higher drift densities and ecologically distinct communities. In a cross-watershed comparison of larval fish drift we find that a seasonal tributary produces more larvae than all other streams/rivers we examined. In a comparison of juvenile Chinook growth morphology between seasonal and permanent streams using geometric morphometrics we find that salmon show phenotypic plasticity and their growth is characteristically different in seasonal tributaries. Taken together, this body of work highlights the critical ecological importance of this habitat.
Forest landscape restoration: linkages with stream fishes of the southern United States
Melvin L. Warren
2012-01-01
With well over 600 native species, the southern United States supports one of the richest temperate freshwater fish faunas on Earth (Fig. 10.1 ). Unfortunately, an expert review revealed that 27% (188 taxa) of southern fishes are endangered, threatened, or vulnerable (Warren et al. 2000 ) and that 16â18% of native fishes are imperiled in 45 of 51 major southern river...
Spatial variation in fish species richness of the upper Mississippi River system
Koel, T.M.
2004-01-01
Important natural environmental gradients, including the connectivity of off-channel aquatic habitats to the main-stem river, have been lost in many reaches of the upper Mississippi River system, and an understanding of the consequences of this isolation is lacking in regard to native fish communities. The objectives of this study were to describe patterns of fish species richness, evenness, and diversity among representative habitats and river reaches and to examine the relationship between fish species richness and habitat diversity. Each year (1994-1999) fish communities of main-channel borders (MCB), side channel borders (SCB), and contiguous backwater shorelines (BWS) were sampled using boat-mounted electrofishing, mini-fyke-nets, tyke nets, hoop nets, and seines at a standardized number of sites. A total of 0.65 million fish were collected, representing 106 species from upper Mississippi River Pools 4, 8, 13, and 26; the open (unimpounded) river reach; and the La Grange Reach of the Illinois River. Within pools, species richness based on rarefaction differed significantly among habitats and was highest in BWS and lowest in MCB (P < 0.0001). At the reach scale, Pools 4, 8, and 13 consistently had the highest species richness and Pool 26, the open-river reach, and the La Grange Reach were significantly lower (P < 0.0001). Species evenness and diversity indices showed similar trends. The relationship between native fish species richness and habitat diversity was highly significant (r(2) = 0.85; P = 0.0091). These results support efforts aimed at the conservation and enhancement of connected side channels and backwaters. Although constrained by dams, pools with high native species richness could serve as a relative reference. The remnants of natural riverine dynamics that remain in these reaches should be preserved and enhanced; conditions could be used to guide restoration activities in more degraded reaches.
The free-flowing Clinch and Powell watershed in Virginia, USA harbors a high number of endemic mussel and fish species but they are declining or going extinct at an alarming rate. In order to prioritize resource management strategies with respect to these fauna, a Graphical Info...
Fishes, mussels, crayfishes, and aquatic habitats of the Hoosier-Shawnee ecological assessment area
M. Burr Brooks; Justin T. Sipiorski; Matthew R. Thomas; Kevin S. Cummings; Christopher A. Taylor
2004-01-01
The Hoosier-Shawnee Ecological Assessment Area, part of the Coastal Plain and Interior Low Plateau physiographic provinces, includes 194 native fish species, 76 native mussel species, and 34 native crayfish species. Five of the subregions (e.g., Mississippi Embayment) that make up the assessment area were recently ranked as either globally or bioregionally outstanding...
Mueller, G.A.; Carpenter, J.; Thornbrugh, D.
2006-01-01
Bullfrog tadpoles (Rana catesbeiana) and red swamp crayfish (Procambarus clarkii) are widespread introduced taxa that are problematic throughout the western United States. Their impact on native amphibians and crustaceans is well documented, but less is known regarding their influence on native fishes. Predator-prey tank tests showed both species consumed eggs and larvae of the endangered razorback sucker (Xyrauchen texanus) in a laboratory setting. Tadpoles consumed 2.2 razorback sucker eggs/d and 1.4 razorback sucker larvae/d, while crayfish ate 6.0 eggs/d and 3.5 larvae/d. Relatively high densities of bullfrog tadpoles and crayfish in razorback sucker spawning areas suggest that these nonnative taxa might pose a threat to the recruitment success of this and other imperiled native fish.
Jack E. Williams; Gordon H. Reeves
2006-01-01
Restored, high-quality streams provide innumerable benefits to society. In the Pacific Northwest, high-quality stream habitat often is associated with an abundance of salmonid fishes such as chinook salmon (Oncorhynchus tshawytscha), coho salmon (O. kisutch), and steelhead (O. mykiss). Many other native...
Hasegawa, K; Mori, T; Yamazaki, C
2017-01-01
The spatial scale and density-dependent effects of non-native brown trout Salmo trutta on species richness of fish assemblages were examined at 48 study sites in Mamachi Stream, a tributary of Chitose River, Hokkaido, Japan. The density of age ≥1 year S. trutta was high in the upstream side of the main stem of Mamachi Stream. Fish species richness increased with increasing area of study sites (habitat size), but the increasing magnitude of the species richness with area decreased with increasing age of ≥1 year S. trutta density. The relationships between age ≥1 year S. trutta, however, and presence-absence of each species seemed to be different among species. Species richness was also determined by location and physical environmental variables, i.e. it was high on the downstream side and in structurally complex environments. © 2016 The Fisheries Society of the British Isles.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-06-17
...--Native Endangered and Threatened Species AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice... requested in accordance with various Federal wildlife conservation laws, including: Endangered Species Act.... [[Page 36238
Lawson, Katelyn M.; Tuckett, Quenton M.; Ritch, Jared L.; Nico, Leo; Fuller, Pam; Matheson, Richard E.; Hill, Jeffrey E.
2017-01-01
The Tampa Bay region of Florida (USA) is a hot spot for non-native freshwater fishes. However, published information on most non-native fishes in the basin is not current. Systematic sampling efforts targeting non-native fishes in the region were conducted from 2013–2015 by the University of Florida Tropical Aquaculture Laboratory. Data from these recent surveys were analyzed, along with historic and new data from published and unpublished sources, to assess current fish distributions and determine status. We focus on five of the non-native species sampled: pike killifish Belonesox belizanus Kner, 1860, green swordtail Xiphophorus hellerii Heckel, 1848, southern platyfish Xiphophorus maculatus (Günther, 1866), Mayan cichlid Mayaheros urophthalmus (Günther, 1862), and Jack Dempsey Rocio octofasciata (Regan, 1903). All five were found to have reproducing populations in the basin, each showing broader distributions than previously indicated. Non-native populations of four of the species have persisted in the Tampa Bay region since at least the 1990s. In contrast, the presence of Mayan cichlid in the basin was not confirmed until 2004. Based on numbers, distributions, and years of persistence, these five species all maintain established populations. Pike killifish and Mayan cichlid are established and spreading throughout multiple habitat types, while green swordtail, southern platyfish, and Jack Dempsey are localized and found primarily in more marginal habitats (e.g., small ditches and first order tributary streams). Factors affecting continued existence and distributions likely include aquaculture, biotic resistance, and thermal and salinity tolerances. We also clarify non-native species status determination using a multi-agency collaborative approach, and reconcile differences in terminology usage and interpretation.
Synergistic impacts by an invasive amphipod and an invasive fish explain native gammarid extinction.
Beggel, S; Brandner, J; Cerwenka, A F; Geist, J
2016-07-14
Worldwide freshwater ecosystems are increasingly affected by invasive alien species. In particular, Ponto-Caspian gobiid fishes and amphipods are suspected to have pronounced effects on aquatic food webs. However, there is a lack of systematic studies mechanistically testing the potential synergistic effects of invasive species on native fauna. In this study we investigated the interrelations between the invasive amphipod Dikerogammarus villosus and the invasive fish species Neogobius melanostomus in their effects on the native amphipod Gammarus pulex. We hypothesized selective predation by the fish as a driver for displacement of native species resulting in potential extinction of G. pulex. The survival of G. pulex in the presence of N. melanostomus in relation to the presence of D. villosus and availability of shelter was analyzed in the context of behavioural differences between the amphipod species. Gammarus pulex had a significantly higher susceptibility to predation by N. melanostomus compared to D. villosus in all experiments, suggesting preferential predation by this fish on native gammarids. Furthermore, the presence of D. villosus significantly increased the vulnerability of G. pulex to fish predation. Habitat structure was an important factor for swimming activity of amphipods and their mortality, resulting in a threefold decrease in amphipods consumed with shelter habitat structures provided. Behavioral differences in swimming activity were additionally responsible for higher predation rates on G. pulex. Intraguild predation could be neglected within short experimental durations. The results of this study provide evidence for synergistic effects of the two invasive Ponto-Caspian species on the native amphipod as an underlying process of species displacements during invasion processes. Prey behaviour and monotonous habitat structures additionally contribute to the decline of the native gammarid fauna in the upper Danube River and elsewhere.
Native fish conservation areas: a vision for large-scale conservation of native fish communities
Jack E. Williams; Richard N. Williams; Russell F. Thurow; Leah Elwell; David P. Philipp; Fred A. Harris; Jeffrey L. Kershner; Patrick J. Martinez; Dirk Miller; Gordon H. Reeves; Christopher A. Frissell; James R. Sedell
2011-01-01
The status of freshwater fishes continues to decline despite substantial conservation efforts to reverse this trend and recover threatened and endangered aquatic species. Lack of success is partially due to working at smaller spatial scales and focusing on habitats and species that are already degraded. Protecting entire watersheds and aquatic communities, which we...
Effects of an introduced piscivorous fish on native benthic fishes in a coastal river
Jason L. White; Bret C. Harvey
2001-01-01
We used field surveys to compare the density and mesohabitat-scale distribution of the native coastrange sculpin (Cottus aleuticus) and the prickly sculpin (C. asper) in coastal rivers in northwestern California, U.S.A., with and without an introduced piscivorous fish, the Sacramento pikeminnow, Ptychocheilus grandis. We also measured mortality of tethered prickly...
Establishment success (numerically or spatially) of an introduced non-native fish species is difficult to predict and its relative status in a fish community can be difficult to measure. We conducted a 2-year, multi-gear survey in the lower St. Louis River, including the DuluthSu...
Torgersen, Christian E.; Hockman-Wert, David P.; Bateman, Douglas S.; Leer, David W.; Gresswell, Robert E.
2007-01-01
The goal of this project was to examine longitudinal patterns in fish assemblages, aquatic habitat, and water temperature in the Lower Crooked River during summer conditions. Specific objectives were to (1) characterize the spatial distribution of native and non-native fishes, (2) describe variation in channel morphology, substrate composition, and water temperature, and (3) evaluate the associations between fishes, aquatic habitat, and water temperature.
Quist, M.C.; Gerow, K.G.; Bower, M.R.; Hubert, W.A.
2006-01-01
Native fishes of the upper Colorado River basin (UCRB) have declined in distribution and abundance due to habitat degradation and interactions with normative fishes. Consequently, monitoring populations of both native and nonnative fishes is important for conservation of native species. We used data collected from Muddy Creek, Wyoming (2003-2004), to compare sample size estimates using a random and a fixed-site sampling design to monitor changes in catch per unit effort (CPUE) of native bluehead suckers Catostomus discobolus, flannelmouth suckers C. latipinnis, roundtail chub Gila robusta, and speckled dace Rhinichthys osculus, as well as nonnative creek chub Semotilus atromaculatus and white suckers C. commersonii. When one-pass backpack electrofishing was used, detection of 10% or 25% changes in CPUE (fish/100 m) at 60% statistical power required 50-1,000 randomly sampled reaches among species regardless of sampling design. However, use of a fixed-site sampling design with 25-50 reaches greatly enhanced the ability to detect changes in CPUE. The addition of seining did not appreciably reduce required effort. When detection of 25-50% changes in CPUE of native and nonnative fishes is acceptable, we recommend establishment of 25-50 fixed reaches sampled by one-pass electrofishing in Muddy Creek. Because Muddy Creek has habitat and fish assemblages characteristic of other headwater streams in the UCRB, our results are likely to apply to many other streams in the basin. ?? Copyright by the American Fisheries Society 2006.
Parasites of native and nonnative fishes of the Little Colorado River, Grand Canyon, Arizona
Choudhury, A.; Hoffnagle, T.L.; Cole, Rebecca A.
2004-01-01
A 2-yr, seasonal, parasitological study of 1,435 fish, belonging to 4 species of native fishes and 7 species of nonnative fishes from the lower Little Colorado River (LCR) and tributary creeks, Grand Canyon, Arizona, yielded 17 species of parasites. These comprised 1 myxozoan (Henneguya exilis), 2 copepods (Ergasilus arthrosis and Lernaea cyprinacea), 1 acarine (Oribatida gen. sp.), 1 piscicolid leech (Myzobdella lugubris), 4 monogeneans (Gyrodactylus hoffmani, Gyrodactylus sp., Dactylogyrus extensus, and Ligictaluridus floridanus), 4 nematodes (Contracaecum sp., Eustrongylides sp., Rhabdochona sp., and Truttaedacnitis truttae), 3 cestodes (Bothriocephalus acheilognathi, Corallobothrium fimbriatum, and Megathylacoides giganteum), and 2 trematodes (Ornithodiplostomum sp. and Posthodiplostomum sp.). Rhabdochona sp. was the only adult parasite native to the LCR. Infection intensities of Ornithodiplostomum sp. and B. acheilognathi were positively correlated with length of the humpback chub Gila cypha. Adult helminths showed a high degree of host specificity, except B. acheilognathi, which was recovered from all fish species examined but was most abundant in cyprinids. Abundance of B. acheilognathi in the humpback chub was highest in the fall and lowest in the summer in both reaches of the LCR. There was no major taxonomic difference in parasite assemblages between the 2 different reaches of the river (LC1 and LC2). Parasite community diversity was very similar in humpback chub, regardless of sampling site or time. The parasite fauna of the LCR is numerically dominated by B. acheilognathi and metacercariae of Ornithodiplostomum sp. The richest and most diverse component community occurred in a nonnative species, the channel catfish Ictalurus punctatus, but infracommunity species richness was highest in a native host, humpback chub.
Poletto, Jamilynn B.; Cocherell, Dennis E.; Mussen, Timothy D.; Ercan, Ali; Bandeh, Hossein; Kavvas, M. Levent; Cech, Joseph J.; Fangue, Nann A.
2015-01-01
Diversion (i.e. extraction) of water from rivers and estuaries can potentially affect native wildlife populations if operation is not carefully managed. For example, open, unmodified water diversions can act as a source of injury or mortality to resident or migratory fishes from entrainment and impingement, and can cause habitat degradation and fragmentation. Fish-protection devices, such as exclusion screens, louvres or sensory deterrents, can physically or behaviourally deter fish from approaching or being entrained into water diversions. However, empirical assessment of their efficacy is often lacking or is investigated only for particular economically or culturally important fishes, such as salmonids. The Southern population of anadromous green sturgeon (Acipenser medirostris) is listed as threatened in California, and there is a high density of water diversions located within their native range (the Sacramento–San Joaquin watershed). Coupled with their unique physiology and behaviour compared with many other fishes native to California, the green sturgeon is susceptible to entrainment into diversions and is an ideal species with which to study the efficacy of mitigation techniques. Therefore, we investigated juvenile green sturgeon (188–202 days post-hatch) in the presence of several fish-protection devices to assess behaviour and entrainment risk. Using a large experimental flume (∼500 kl), we found that compared with an open diversion pipe (control), the addition of a trash-rack box, louvre box, or perforated cylinder on the pipe inlet all significantly reduced the proportion of fish that were entrained through the pipe (P = 0.03, P = 0.028, and P = 0.028, respectively). Likewise, these devices decreased entrainment risk during a single movement past the pipe by between 60 and 96%. These fish-protection devices should decrease the risk of fish entrainment during water-diversion activities. PMID:27293725
California golden trout and climate change: Is their stream habitat vulnerable to climate warming?
Kathleen R. Matthews
2010-01-01
The California golden trout (CGT) Oncorhynchus mykiss aguabonita is one of the few native high-elevation fish in the Sierra Nevada. They are already in trouble because of exotic trout, genetic introgression, and degraded habitat, and now face further stress from climate warming. Their native habitat on the Kern Plateau meadows mostly in the Golden...
Yao, Weiwei; Chen, Yuansheng
2018-04-01
Colorado River is a unique ecosystem and provides important ecological services such as habitat for fish species as well as water power energy supplies. River management for this ecosystem requires assessment and decision support tools for fish which involves protecting, restoring as well as forecasting of future conditions. In this paper, a habitat and population model was developed and used to determine the levels of fish habitat suitability and population density in Colorado River between Lees Ferry and Lake Mead. The short term target fish populations are also predicted based on native fish recovery strategy. This model has been developed by combining hydrodynamics, heat transfer and sediment transport models with a habitat suitability index model and then coupling with habitat model into life stage population model. The fish were divided into four life stages according to the fish length. Three most abundant and typical native and non-native fish were selected as target species, which are rainbow trout (Oncorhynchus mykiss), brown trout (Salmo trutta) and flannelmouth sucker (Catostomus latipinnis). Flow velocity, water depth, water temperature and substrates were used as the suitability indicators in habitat model and overall suitability index (OSI) as well as weight usable area (WUA) was used as an indicator in population model. A comparison was made between simulated fish population alteration and surveyed fish number fluctuation during 2000 to 2009. The application of this habitat and population model indicates that this model can be accurate present habitat situation and targets fish population dynamics of in the study areas. The analysis also indicates the flannelmouth sucker population will steadily increase while the rainbow trout will decrease based on the native fish recovery scheme. Copyright © 2018. Published by Elsevier Inc.
A fish survey of the White River, Nevada
Scoppettone, G. Gary; Rissler, Peter H.; Shea, Sean
2004-01-01
In spring and summer 1991 and 1992, we surveyed fishes of the White River system, Nye and White Pine Counties, Nevada, to determine the status of natives. There are 5 known native fishes to the White River: Lepidomeda albivallis (White River spinedace), Crenichthys baileyi albivallis (Preston White River springfish), Crenichthys baileyi thermophilus (Moorman White River springfish), Catostomus clarki intermedius (White River desert sucker), and Rhinichthys osculus ssp. (White River speckled dace). All 5 had declined in range. Lepidomeda albivallis had experienced the greatest decline, with less than 50 remaining, and these were restricted to a 70-m stream reach. Rhinichthys osculus spp. was most widespread, found in 18 spring systems. Cottus bairdi (mottled sculpin) was collected for the 1st time from the White River system, where it was probably native. Protective measures should be implemented to conserve all native White River fishes to include C. bairdi.
Predator effects on reef fish settlement depend on predator origin and recruit density.
Benkwitt, Cassandra E
2017-04-01
During major life-history transitions, animals often experience high mortality rates due to predation, making predator avoidance particularly advantageous during these times. There is mixed evidence from a limited number of studies, however, regarding how predator presence influences settlement of coral-reef fishes and it is unknown how other potentially mediating factors, including predator origin (native vs. nonnative) or interactions among conspecific recruits, mediate the non-consumptive effects of predators on reef fish settlement. During a field experiment in the Caribbean, approximately 52% fewer mahogany snapper (Lutjanus mahogoni) recruited to reefs with a native predator (graysby grouper, Cephalopholis cruentata) than to predator-free control reefs and reefs with an invasive predator (red lionfish, Pterois volitans) regardless of predator diet. These results suggest that snapper recruits do not recognize nonnative lionfish as a threat. However, these effects depended on the density of conspecific recruits, with evidence that competition may limit the response of snapper to even native predators at the highest recruit densities. In contrast, there was no effect of predator presence or conspecific density on the recruitment of bicolor damselfish (Stegastes partitus). These context-dependent responses of coral-reef fishes to predators during settlement may influence individual survival and shape subsequent population and community dynamics. © 2017 by the Ecological Society of America.
May, J.T.; Brown, L.R.
2002-01-01
The associations of resident fish communities with environmental variables and stream condition were evaluated at representative sites within the Sacramento River Basin, California between 1996 and 1998 using multivariate ordination techniques and by calculating six fish community metrics. In addition, the results of the current study were compared with recent studies in the San Joaquin River drainage to provide a wider perspective of the condition of resident fish communities in the Central Valley of California as a whole. Within the Sacramento drainage, species distributions were correlated with elevational and substrate size gradients; however, the elevation of a sampling site was correlated with a suite of water-quality and habitat variables that are indicative of land use effects on physiochemical stream parameters. Four fish community metrics - percentage of native fish, percentage of intolerant fish, number of tolerant species, and percentage of fish with external anomalies - were responsive to environmental quality. Comparisons between the current study and recent studies in the San Joaquin River drainage suggested that differences in water-management practices may have significant effects on native species fish community structure. Additionally, the results of the current study suggest that index of biotic integrity-type indices can be developed for the Sacramento River Basin and possibly the entire Central Valley, California. The protection of native fish communities in the Central Valley and other arid environments continues to be a conflict between human needs for water resources and the requirements of aquatic ecosystems; preservation of these ecosystems will require innovative management strategies.
Fish community change in Lake Superior, 1970-2000
Bronte, Charles R.; Ebener, Mark P.; Schreiner, Donald R.; DeVault, David S.; Petzold, Michael M.; Jensen, Douglas A.; Richards, Carl; Lozano, Steven J.
2003-01-01
Changes in Lake Superior's fish community are reviewed from 1970 to 2000. Lake trout (Salvelinus namaycush) and lake whitefish (Coregonus clupeaformis) stocks have increased substantially and may be approaching ancestral states. Lake herring (Coregonus artedi) have also recovered, but under sporadic recruitment. Contaminant levels have declined and are in equilibrium with inputs, but toxaphene levels are higher than in all other Great Lakes. Sea lamprey (Petromyzon marinus) control, harvest limits, and stocking fostered recoveries of lake trout and allowed establishment of small nonnative salmonine populations. Natural reproduction supports most salmonine populations, therefore further stocking is not required. Nonnative salmonines will likely remain minor components of the fish community. Forage biomass has shifted from exotic rainbow smelt (Osmerus mordax) to native species, and high predation may prevent their recovery. Introductions of exotics have increased and threaten the recovering fish community. Agencies have little influence on the abundance of forage fish or the major predator, siscowet lake trout, and must now focus on habitat protection and enhancement in nearshore areas and prevent additional species introductions to further restoration. Persistence of Lake Superior's native deepwater species is in contrast to other Great Lakes where restoration will be difficult in the absence of these ecologically important fishes.
Karen L. Pope; Justin M. Garwood; Hartwell H. Welsh Jr.; Sharon P. Lawler
2008-01-01
Hyperpredation occurs when non-native prey facilitate invasive predators, which then suppress native prey. Direct impacts of introduced fish on amphibians are well studied, but the role of fish in supporting shared predators has not been considered. We present evidence for indirect effects of trout on amphibians through snake predation. Analyses of the diet,...
NASA Astrophysics Data System (ADS)
Leke, J. R.; Mandey, J. S.; Laihad, J. T.; Tinangon, R. M.; Tangkau, L.; Junus, C.
2018-01-01
The study was conducted to determine the use of fish oil as by-product of fish canning factory in diet on the performance and lipid profiles of native chickens. The experiment used 100 native chicken with an average initial body weight of 48,9 gram (sd + 9.9), was used in this study for 8 weeks experiment. These were arranged by a completely randomized design with 5 treatments, 5 replications and 4 hens in replication each. The diets were: R0 = 100% Based Diet (BD) + 0% Fish Oil (FO); R1 = 98.5% BD + 1.5% FO; R2 = 98% BD + 2% FO; R3 = 97.5% BD + 2.5% FO; R4 = 97 % BD + 3% FO. Feed and water were provided ad libitum. Variables were performance parameters and lipid profiles. Results showed that fish oil inclusion in diets were significantly increased feed intake, body weight gain, carcass percentage, liver, breast and thigh weight, and decreased blood cholesterol, carbohydrate and meat cholesterol, and also tended to decrease abdominal fat. However, there were no affected on feed conversion, water, protein, fat and ash of breast meat. It can be concluded that the use of fish oil in diet up to 3% could improved performance parameters of native chickens.
Carbon dioxide as an under-ice lethal control for invasive fishes
Cupp, Aaron R.; Woiak, Zebadiah; Erickson, Richard A.; Amberg, Jon J.; Gaikowski, Mark
2017-01-01
Resource managers need effective tools to control invasive fish populations. In this study, we tested under-ice carbon dioxide (CO2) injection as a novel piscicide method for non-native Silver Carp (Hypophthalmichthys molitrix), Bighead Carp (Hypophthalmichthys nobilis), Grass Carp (Ctenopharyngodon idella), Common Carp (Cyprinus carpio) and native Bigmouth Buffalo (Ictiobus cyprinellus). Fish were held overwinter in nine outdoor ponds (0.04 ha surface area; 340,000 L volume) treated with no CO2 (control), 43.5–44.0 kg CO2 (low treatment), and 87.5–88.5 kg CO2 (high treatment). Ponds were harvested immediately after ice-out to assess survival and condition. Resulting survival in low (mean = 32%) and high (mean = 5%) CO2-treated ponds was significantly lower than untreated control ponds (mean = 84%). Lethal efficacy varied across species with no Bighead Carp, Silver Carp, or Bigmouth Buffalo surviving the high CO2 treatment. External infections were observed more frequently after CO2 treatments (means = 49–67%) relative to untreated ponds (mean = 2%), suggesting a secondary mechanism for poor survival. This study demonstrates that CO2 can be used as a lethal control for invasive fishes, but effectiveness may vary by species and CO2concentration.
Weidel, Brian C.; Dunlop, Erin
2017-01-01
Prey fish communities across the Great Lakes continue to change, although the direction and magnitude of those changes are not consistent across the lakes. The metrics used to categorize prey fish status in this and previous periods are based on elements that are common among each of the lake’s Fish Community Objectives and include diversity and the relative role of native species in the prey fish communities. The diversity index categorized three of lakes as ‘fair’, while Superior and Erie were ‘good’ (Table 1). The short term trend, from the previous period (2008-2010) to the current period (2011-2014) found diversity in Erie and Superior to be unchanging, but the other three lakes to be ‘deteriorating’, resulting in an overall trend categorization of ‘undetermined’ (Table 1). The long term diversity trend suggested Lakes Superior and Erie have the most diverse prey communities although the index for those prey fish have been quite variable over time (Figure 1). In Lake Huron, where non-native alewife have substantially declined, the diversity index has also declined. The continued dominance of alewife in Lake Ontario (96% of the prey fish biomass) resulted in the lowest diversity index value (Figure 1). The proportion of native species within the community was judged as ‘good’ in Lakes Superior and Huron, ‘fair’ in Michigan and Erie and ‘poor’ in Ontario (Table 2). The short term trend was improving in in all lakes except Michigan (‘deteriorating’) and Ontario (‘unchanging’), resulting in an overall short term trend of ‘undetermined’ (Table 2). Over the current period, Lake Superior consistently had the highest proportion native prey fish (87%) while Lake Ontario had the lowest (1%) (Figure 2). Lake Michigan’s percent native has declined as round goby increase and comprises a greater proportion of the community. Native prey fish make up 51% of Lake Erie, although basin-specific values differed (Figure 2). Most notably, native species in Lake Huron comprised less than 10% of the community in 1970, but since alewife have declined, now represent nearly 80% of the community (Figure 2). Prey fish data are most consistent for in-lake populations, which are reported here; data from connecting channels was not consistently available across the basin. Abundance was not used to judge prey fish status since successful, basin-wide management actions, including mineral nutrient input reductions and piscivore restoration, both inherently reduce prey fish abundance. However, recent abundance trends as they relate to predator prey balance are referenced, such as in Lakes Michigan and Huron where piscivore stocking is being reduced to lower predation demand on prey fish populations and maintain sport fisheries.
The St. Louis River freshwater estuary which drains into western Lake Superior and includes the Duluth-Superior (MN-WI) harbor, has a long history of non-native fish introductions. From 1985 to 2002, seven new fishes were identified in the estuary, an unprecedented rate of non-n...
Culvert roughness elements for native Utah fish passage : phase I.
DOT National Transportation Integrated Search
2011-01-01
Laboratory flume testing of native Utah non-salmonid fish was performed to observe how : they use altered flow around obstacles to swim upstream. Three experimental setups included : a bare Plexiglas flume, vertical cylinders, and natural substrate p...
Lost, a desert river and its native fishes: A historical perspective of the lower Colorado River
Mueller, Gordon A.; Marsh, Paul C.
2002-01-01
The Colorado River had one of the most unique fish communities in the world. Seventy-five percent of those species were found no where else in the world. Settlement of the lower basin brought dramatic changes to both the river and its native fish. Those changes began more than 120 years ago as settlers began stocking nonnative fishes. By 1930, nonnative fish had spread throughout the lower basin and replaced native communities. All resemblance of historic river conditions faded with the construction of Hoover Dam in 1935 and other large water development projects. Today, few remember what the Colorado River was really like. Seven of the nine mainstream fishes are now federally protected as endangered. Federal and state agencies are attempting to recover these fish; however, progress has been frustrated due to the severity of human impact. This report presents testimony, old descriptions, and photographs describing the changes that have taken place in hopes that it will provide managers, biologists, and the interested public a better appreciation of the environment that shaped these unique fish.
Predation on exotic zebra mussels by native fishes: Effects on predator and prey
Magoulick, D.D.; Lewis, L.C.
2002-01-01
1. Exotic zebra mussels, Dreissena polymorpha, occur in southern U.S. waterways in high densities, but little is known about the interaction between native fish predators and zebra mussels. Previous studies have suggested that exotic zebra mussels are low profitability prey items and native vertebrate predators are unlikely to reduce zebra mussel densities. We tested these hypotheses by observing prey use of fishes, determining energy content of primary prey species of fishes, and conducting predator exclusion experiments in Lake Dardanelle, Arkansas. 2. Zebra mussels were the primary prey eaten by 52.9% of blue catfish, Ictalurus furcatus; 48.2% of freshwater drum, Aplodinotus grunniens; and 100% of adult redear sunfish, Lepomis microlophus. Blue catfish showed distinct seasonal prey shifts, feeding on zebra mussels in summer and shad, Dorosoma spp., during winter. Energy content (joules g-1) of blue catfish prey (threadfin shad, Dorosoma petenense; gizzard shad, D. cepedianum; zebra mussels; and asiatic clams, Corbicula fluminea) showed a significant species by season interaction, but shad were always significantly greater in energy content than bivalves examined as either ash-free dry mass or whole organism dry mass. Fish predators significantly reduced densities of large zebra mussels (>5 mm length) colonising clay tiles in the summers of 1997 and 1998, but predation effects on small zebra mussels (???5 mm length) were less clear. 3. Freshwater drum and redear sunfish process bivalve prey by crushing shells and obtain low amounts of higher-energy food (only the flesh), whereas blue catfish lack a shell-crushing apparatus and ingest large amounts of low-energy food per unit time (bivalves with their shells). Blue catfish appeared to select the abundant zebra mussel over the more energetically rich shad during summer, then shifted to shad during winter when shad experienced temperature-dependent stress and mortality. Native fish predators can suppress adult zebra mussel colonisation, but are ultimately unlikely to limit population density because of zebra mussel reproductive potential.
Eidam, Dona M; von Hippel, Frank A; Carlson, Matthew L; Lassuy, Dennis R; López, J Andrés
2016-07-01
Introduced non-native fishes have the potential to substantially alter aquatic ecology in the introduced range through competition and predation. The Alaska blackfish ( Dallia pectoralis ) is a freshwater fish endemic to Chukotka and Alaska north of the Alaska Range (Beringia); the species was introduced outside of its native range to the Cook Inlet Basin of Alaska in the 1950s, where it has since become widespread. Here we characterize the diet of Alaska blackfish at three Cook Inlet Basin sites, including a lake, a stream, and a wetland. We analyze stomach plus esophageal contents to assess potential impacts on native species via competition or predation. Alaska blackfish in the Cook Inlet Basin consume a wide range of prey, with major prey consisting of epiphytic/benthic dipteran larvae, gastropods, and ostracods. Diets of the introduced populations of Alaska blackfish are similar in composition to those of native juvenile salmonids and stickleback. Thus, Alaska blackfish may affect native fish populations via competition. Fish ranked third in prey importance for both lake and stream blackfish diets but were of minor importance for wetland blackfish.
Eidam, Dona M.; Carlson, Matthew L.; Lassuy, Dennis R.; López, J. Andrés
2016-01-01
Introduced non-native fishes have the potential to substantially alter aquatic ecology in the introduced range through competition and predation. The Alaska blackfish (Dallia pectoralis) is a freshwater fish endemic to Chukotka and Alaska north of the Alaska Range (Beringia); the species was introduced outside of its native range to the Cook Inlet Basin of Alaska in the 1950s, where it has since become widespread. Here we characterize the diet of Alaska blackfish at three Cook Inlet Basin sites, including a lake, a stream, and a wetland. We analyze stomach plus esophageal contents to assess potential impacts on native species via competition or predation. Alaska blackfish in the Cook Inlet Basin consume a wide range of prey, with major prey consisting of epiphytic/benthic dipteran larvae, gastropods, and ostracods. Diets of the introduced populations of Alaska blackfish are similar in composition to those of native juvenile salmonids and stickleback. Thus, Alaska blackfish may affect native fish populations via competition. Fish ranked third in prey importance for both lake and stream blackfish diets but were of minor importance for wetland blackfish. PMID:28082763
Sanches, Fábio Henrique Carretero; Miyai, Caio Akira; Costa, Tânia Márcia; Christofoletti, Ronaldo Adriano; Volpato, Gilson Luiz; Barreto, Rodrigo Egydio
2012-01-01
Approximately 50 years ago, Nile tilapia were accidentally introduced to Brazil, and the decline of pearl cichlid populations, which has been intensified by habitat degradation, in some locations has been associated with the presence of Nile tilapia. There is, however, little strong empirical evidence for the negative interaction of non-native fish populations with native fish populations; such evidence would indicate a potential behavioural mechanism that could cause the population of the native fish to decline. In this study, we show that in fights staged between pairs of Nile tilapia and pearl cichlids of differing body size, the Nile tilapia were more aggressive than the pearl cichlid. Because this effect prevailed over body-size effects, the pearl cichlids were at a disadvantage. The niche overlap between the Nile tilapia and the pearl cichlid in nature, and the competitive advantage shown by the Nile tilapia in this study potentially represent one of several possible results of the negative interactions imposed by an invasive species. These negative effects may reduce population viability of the native species and cause competitive exclusion.
Linking removal targets to the ecological effects of invaders: a predictive model and field test.
Green, Stephanie J; Dulvy, Nicholas K; Brooks, Annabelle M L; Akins, John L; Cooper, Andrew B; Miller, Skylar; Côté, Isabelle M
Species invasions have a range of negative effects on recipient ecosystems, and many occur at a scale and magnitude that preclude complete eradication. When complete extirpation is unlikely with available management resources, an effective strategy may be to suppress invasive populations below levels predicted to cause undesirable ecological change. We illustrated this approach by developing and testing targets for the control of invasive Indo-Pacific lionfish (Pterois volitans and P. miles) on Western Atlantic coral reefs. We first developed a size-structured simulation model of predation by lionfish on native fish communities, which we used to predict threshold densities of lionfish beyond which native fish biomass should decline. We then tested our predictions by experimentally manipulating lionfish densities above or below reef-specific thresholds, and monitoring the consequences for native fish populations on 24 Bahamian patch reefs over 18 months. We found that reducing lionfish below predicted threshold densities effectively protected native fish community biomass from predation-induced declines. Reductions in density of 25–92%, depending on the reef, were required to suppress lionfish below levels predicted to overconsume prey. On reefs where lionfish were kept below threshold densities, native prey fish biomass increased by 50–70%. Gains in small (<6 cm) size classes of native fishes translated into lagged increases in larger size classes over time. The biomass of larger individuals (>15 cm total length), including ecologically important grazers and economically important fisheries species, had increased by 10–65% by the end of the experiment. Crucially, similar gains in prey fish biomass were realized on reefs subjected to partial and full removal of lionfish, but partial removals took 30% less time to implement. By contrast, the biomass of small native fishes declined by >50% on all reefs with lionfish densities exceeding reef-specific thresholds. Large inter-reef variation in the biomass of prey fishes at the outset of the study, which influences the threshold density of lionfish, means that we could not identify a single rule of thumb for guiding control efforts. However, our model provides a method for setting reef-specific targets for population control using local monitoring data. Our work is the first to demonstrate that for ongoing invasions, suppressing invaders below densities that cause environmental harm can have a similar effect, in terms of protecting the native ecosystem on a local scale, to achieving complete eradication.
NASA Astrophysics Data System (ADS)
Kotta, Jonne; Orav-Kotta, Helen; Herkül, Kristjan
2010-10-01
The North-American amphipod Gammarus tigrinus was observed for the first time in the northern Baltic Sea in 2003. The invasive amphipod has been particularly successful in some habitats (e.g. on pebbles) where it has become one of the most abundant gammarid species. We studied experimentally if the dominant fish Gasterosteus aculeatus preyed differentially on the exotic G. tigrinus and the native Gammarus salinus, if predation differed among habitats, and if one gammarid species facilitated predation on the other. The experiment demonstrated that (1) fish preyed more on the exotic G. tigrinus than the native G. salinus. (2) Predation did not differ among habitats. (3) Gammarus tigrinus facilitated the predation on G. salinus and this facilitation varied among habitats with significant effects on pebbles. Thus, the combined effect of habitat-specific fish predation and competition between gammarid amphipods is a possible explanation of the current range of G. tigrinus in the northern Baltic Sea. G. tigrinus seems to establish in habitats where it can significantly increase fish predation on the native gammarids.
Invasive lionfish reduce native fish abundance on a regional scale
NASA Astrophysics Data System (ADS)
Ballew, Nicholas G.; Bacheler, Nathan M.; Kellison, G. Todd; Schueller, Amy M.
2016-08-01
Invasive lionfish pose an unprecedented threat to biodiversity and fisheries throughout Atlantic waters off of the southeastern United States, the Caribbean, and the Gulf of Mexico. Here, we employ a spatially replicated Before-After-Control-Impact analysis with temporal pairing to quantify for the first time the impact of the lionfish invasion on native fish abundance across a broad regional scale and over the entire duration of the lionfish invasion (1990-2014). Our results suggest that 1) lionfish-impacted areas off of the southeastern United States are most prevalent off-shore near the continental shelf-break but are also common near-shore and 2) in impacted areas, lionfish have reduced tomtate (a native forage fish) abundance by 45% since the invasion began. Tomtate served as a model native fish species in our analysis, and as such, it is likely that the lionfish invasion has had similar impacts on other species, some of which may be of economic importance. Barring the development of a control strategy that reverses the lionfish invasion, the abundance of lionfish in the Atlantic, Caribbean, and Gulf of Mexico will likely remain at or above current levels. Consequently, the effect of lionfish on native fish abundance will likely continue for the foreseeable future.
Invasive lionfish reduce native fish abundance on a regional scale.
Ballew, Nicholas G; Bacheler, Nathan M; Kellison, G Todd; Schueller, Amy M
2016-08-31
Invasive lionfish pose an unprecedented threat to biodiversity and fisheries throughout Atlantic waters off of the southeastern United States, the Caribbean, and the Gulf of Mexico. Here, we employ a spatially replicated Before-After-Control-Impact analysis with temporal pairing to quantify for the first time the impact of the lionfish invasion on native fish abundance across a broad regional scale and over the entire duration of the lionfish invasion (1990-2014). Our results suggest that 1) lionfish-impacted areas off of the southeastern United States are most prevalent off-shore near the continental shelf-break but are also common near-shore and 2) in impacted areas, lionfish have reduced tomtate (a native forage fish) abundance by 45% since the invasion began. Tomtate served as a model native fish species in our analysis, and as such, it is likely that the lionfish invasion has had similar impacts on other species, some of which may be of economic importance. Barring the development of a control strategy that reverses the lionfish invasion, the abundance of lionfish in the Atlantic, Caribbean, and Gulf of Mexico will likely remain at or above current levels. Consequently, the effect of lionfish on native fish abundance will likely continue for the foreseeable future.
Invasive lionfish reduce native fish abundance on a regional scale
Ballew, Nicholas G.; Bacheler, Nathan M.; Kellison, G. Todd; Schueller, Amy M.
2016-01-01
Invasive lionfish pose an unprecedented threat to biodiversity and fisheries throughout Atlantic waters off of the southeastern United States, the Caribbean, and the Gulf of Mexico. Here, we employ a spatially replicated Before-After-Control-Impact analysis with temporal pairing to quantify for the first time the impact of the lionfish invasion on native fish abundance across a broad regional scale and over the entire duration of the lionfish invasion (1990–2014). Our results suggest that 1) lionfish-impacted areas off of the southeastern United States are most prevalent off-shore near the continental shelf-break but are also common near-shore and 2) in impacted areas, lionfish have reduced tomtate (a native forage fish) abundance by 45% since the invasion began. Tomtate served as a model native fish species in our analysis, and as such, it is likely that the lionfish invasion has had similar impacts on other species, some of which may be of economic importance. Barring the development of a control strategy that reverses the lionfish invasion, the abundance of lionfish in the Atlantic, Caribbean, and Gulf of Mexico will likely remain at or above current levels. Consequently, the effect of lionfish on native fish abundance will likely continue for the foreseeable future. PMID:27578096
Schofield, Pamela J.; Slone, Daniel H.; Gregoire, Denise R.; Loftus, William F.
2014-01-01
In an 8-month mesocosm experiment, we examined how a simulated Everglades aquatic community of small native fishes, snails, and shrimp changed with the addition of either a native predator (dollar sunfish Lepomis marginatus) or a non-native predator (African jewelfish Hemichromis letourneuxi) compared to a no-predator control. Two snail species (Planorbella duryi, Physella cubensis) and the shrimp (Palaemonetes paludosus) displayed the strongest predator-treatment effects, with significantly lower biomasses in tanks with Hemichromis. One small native fish (Heterandria formosa) was significantly less abundant in Hemichromis tanks, but there were no significant treatment effects for Gambusia holbrooki, Jordanella floridae, or Pomacea paludosa (applesnail). Overall, there were few treatment differences between native predator and no-predator control tanks. The results suggest that the potential of Hemichromis to affect basal food-web species that link primary producers with higher-level consumers in the aquatic food web, with unknown consequences for Florida waters.
Ramírez-Herrejón, Juan P; Mercado-Silva, Norman; Balart, Eduardo F; Moncayo-Estrada, Rodrigo; Mar-Silva, Valentín; Caraveo-Patiño, Javier
2015-09-01
Non-native species are often major drivers of the deterioration of natural ecosystems. The common carp Cyprinus carpio are known to cause major changes in lentic systems, but may not be solely responsible for large scale changes in these ecosystems. We used data from extensive collection efforts to gain insight into the importance of carp as drivers of ecosystem change in Lake Patzcuaro, Mexico. We compared the structure (fish density, biomass, diversity, and evenness) of fish assemblages from six Lake Patzcuaro sites with different habitat characteristics. Intersite comparisons were carried out for both wet and dry seasons. We explored the relationships between non-carp species and carp; and studied multivariate interactions between fish abundance and habitat characteristics. From a biomass perspective, carp was dominant in only four of six sites. In terms of density, carp was not a dominant species in all sites. Further, carp density and biomass were not negatively related to native species density and biomass, even when carp density and biomass were positively correlated to water turbidity levels. Carp dominated fish assemblages in the shallowest sites with the highest water turbidity, plant detritus at the bottom, and floating macrophytes covering the lake surface. These results suggest that the effect of carp on fish assemblages may be highly dependent on habitat characteristics in Lake Patzcuaro. Watershed degradation, pollution, water level loss, and other sources of anthropogenic influence may be more important drivers of Lake Patzcuaro degradation than the abundance of carp.
NASA Astrophysics Data System (ADS)
Ramírez-Herrejón, Juan P.; Mercado-Silva, Norman; Balart, Eduardo F.; Moncayo-Estrada, Rodrigo; Mar-Silva, Valentín; Caraveo-Patiño, Javier
2015-09-01
Non-native species are often major drivers of the deterioration of natural ecosystems. The common carp Cyprinus carpio are known to cause major changes in lentic systems, but may not be solely responsible for large scale changes in these ecosystems. We used data from extensive collection efforts to gain insight into the importance of carp as drivers of ecosystem change in Lake Patzcuaro, Mexico. We compared the structure (fish density, biomass, diversity, and evenness) of fish assemblages from six Lake Patzcuaro sites with different habitat characteristics. Intersite comparisons were carried out for both wet and dry seasons. We explored the relationships between non-carp species and carp; and studied multivariate interactions between fish abundance and habitat characteristics. From a biomass perspective, carp was dominant in only four of six sites. In terms of density, carp was not a dominant species in all sites. Further, carp density and biomass were not negatively related to native species density and biomass, even when carp density and biomass were positively correlated to water turbidity levels. Carp dominated fish assemblages in the shallowest sites with the highest water turbidity, plant detritus at the bottom, and floating macrophytes covering the lake surface. These results suggest that the effect of carp on fish assemblages may be highly dependent on habitat characteristics in Lake Patzcuaro. Watershed degradation, pollution, water level loss, and other sources of anthropogenic influence may be more important drivers of Lake Patzcuaro degradation than the abundance of carp.
Land, lake, and fish: Investigation of fish remains from Gesher Benot Ya'aqov (paleo-Lake Hula).
Zohar, Irit; Biton, Rebecca
2011-04-01
The question of whether or not pre-modern hominins were responsible for the accumulation of fish remains is discussed through analyses of remains recovered from two lacustrine facies (I-4 and I-5) from Area A of the Acheulian site of Gesher Benot Ya'aqov (GBY) in the Jordan Rift Valley, Israel. The fish remains provide the first glimpse into the naturally accumulated fish assemblage from the fluctuating shores of a lake that had been continually exploited by early hominins some 780,000 years ago. Preliminary analysis of the remains show that thirteen of the seventeen species native to Lake Hula were identified at GBY. These represent three of the five freshwater fish families native to the lake: Cyprinidae (carps), Cichlidae (tilapini, St. Peter's fish), and Clariidae (catfish). From a taphonomical perspective, a significant difference is found between the two lithofacies (Layers I-4 and I-5) in terms of species composition, richness, diversity, and skeleton completeness. It appears that the fish remains recovered from Layer I-4 (clay) are better preserved than those from Layer I-5 (coquina). In both lithofacies, Cyprinidae are highly abundant while Cichlidae and Clariidae are rare and under-represented, especially when compared to the Lake Hula fishery report from the 1950s. All of these identified species may have contributed significantly to the diet of GBY hominins. Copyright © 2010 Elsevier Ltd. All rights reserved.
Fragoso-Moura, E N; Oporto, L T; Maia-Barbosa, P M; Barbosa, F A R
2016-02-01
The introduction of species has become an important problem for biodiversity and natural ecosystem conservation. The lake system of the middle Rio Doce (MG, Brazil) comprises c. 200 lakes at various conservation states, of which 50 are located within the Rio Doce State Park (PERD). Previous studies had verified several of these lakes suffered non-native fishes introductions and the presence of these species needs for the implementation of actions aiming at not only their control but also the preservation of the native species. This study discusses the effects of non-native fish species in the largest conservation unit of Atlantic Forest in Minas Gerais, southeast of Brazil, using data from 1983 to 2010 distributed as follow: data prior to 2006 were obtained from previous studies, and data from September 2006 to July 2010 were obtained in Lake Carioca at four sampling stations using gillnets, seine nets and sieve. A total of 17 fish species was collected (2006-2010) of which five were introduced species. Among the small to medium size native species (30 to 2000 mm standard length) seven had disappeared, two are new records and one was recaptured. The non-native species Cichla kelberi (peacock bass) and Pygocentrus nattereri (red piranha) are within the most abundant captured species. Integrated with other actions, such as those preventing new introductions, a selective fishing schedule is proposed as an alternative approach to improve the conservation management actions and the local and regional biodiversity maintenance.
Role of origin and release location in pre-spawning distribution and movements of anadromous alewife
Frank, Holly J.; Mather, M. E.; Smith, Joseph M.; Muth, Robert M.; Finn, John T.
2011-01-01
Capturing adult anadromous fish that are ready to spawn from a self sustaining population and transferring them into a depleted system is a common fisheries enhancement tool. The behaviour of these transplanted fish, however, has not been fully evaluated. The movements of stocked and native anadromous alewife, Alosa pseudoharengus (Wilson), were monitored in the Ipswich River, Massachusetts, USA, to provide a scientific basis for this management tool. Radiotelemetry was used to examine the effect of origin (native or stocked) and release location (upstream or downstream) on distribution and movement during the spawning migration. Native fish remained in the river longer than stocked fish regardless of release location. Release location and origin influenced where fish spent time and how they moved. The spatial mosaic of available habitats and the entire trajectory of freshwater movements should be considered to restore effectively spawners that traverse tens of kilometres within coastal rivers.
Hargrove, John S; Weyl, Olaf L F; Allen, Micheal S; Deacon, Neil R
2015-01-01
Fishes are one of the most commonly introduced aquatic taxa worldwide, and invasive fish species pose threats to biodiversity and ecosystem function in recipient waters. Considerable research efforts have focused on predicting the invasibility of different fish taxa; however, accurate records detailing the establishment and spread of invasive fishes are lacking for large numbers of fish around the globe. In response to these data limitations, a low-cost method of cataloging and quantifying the temporal and spatial status of fish invasions was explored. Specifically, angler catch data derived from competitive bass angling tournaments was used to document the distribution of 66 non-native populations of black bass (Micropterus spp.) in southern Africa. Additionally, catch data from standardized tournament events were used to assess the abundance and growth of non-native bass populations in southern Africa relative to their native distribution (southern and eastern United States). Differences in metrics of catch per unit effort (average number of fish retained per angler per day), daily bag weights (the average weight of fish retained per angler), and average fish weight were assessed using catch data from 14,890 angler days of tournament fishing (11,045 days from South Africa and Zimbabwe; 3,845 days from the United States). No significant differences were found between catch rates, average daily bag weight, or the average fish weight between countries, suggesting that bass populations in southern Africa reach comparable sizes and numbers relative to waters in their native distribution. Given the minimal cost associated with data collection (i.e. records are collected by tournament organizers), the standardized nature of the events, and consistent bias (i.e. selection for the biggest fish in a population), the use of angler catch data represents a novel approach to infer the status and distribution of invasive sport fish.
Hargrove, John S.; Weyl, Olaf L. F.; Allen, Micheal S.; Deacon, Neil R.
2015-01-01
Fishes are one of the most commonly introduced aquatic taxa worldwide, and invasive fish species pose threats to biodiversity and ecosystem function in recipient waters. Considerable research efforts have focused on predicting the invasibility of different fish taxa; however, accurate records detailing the establishment and spread of invasive fishes are lacking for large numbers of fish around the globe. In response to these data limitations, a low-cost method of cataloging and quantifying the temporal and spatial status of fish invasions was explored. Specifically, angler catch data derived from competitive bass angling tournaments was used to document the distribution of 66 non-native populations of black bass (Micropterus spp.) in southern Africa. Additionally, catch data from standardized tournament events were used to assess the abundance and growth of non-native bass populations in southern Africa relative to their native distribution (southern and eastern United States). Differences in metrics of catch per unit effort (average number of fish retained per angler per day), daily bag weights (the average weight of fish retained per angler), and average fish weight were assessed using catch data from 14,890 angler days of tournament fishing (11,045 days from South Africa and Zimbabwe; 3,845 days from the United States). No significant differences were found between catch rates, average daily bag weight, or the average fish weight between countries, suggesting that bass populations in southern Africa reach comparable sizes and numbers relative to waters in their native distribution. Given the minimal cost associated with data collection (i.e. records are collected by tournament organizers), the standardized nature of the events, and consistent bias (i.e. selection for the biggest fish in a population), the use of angler catch data represents a novel approach to infer the status and distribution of invasive sport fish. PMID:26047487
Fish assemblage structure in an Oklahoma Ozark stream before and after rainbow trout introduction
Walsh, M.G.; Winkelman, D.L.
2005-01-01
Rainbow trout Oncorhynchus mykiss have been widely stocked throughout the United States as a popular sport fish. Our study was initiated to evaluate potential effects of rainbow trout introduction on native fishes to inform future decisions about trout stocking in northeastern Oklahoma streams. We sampled fish assemblages in pools, glides, and riffles in Brush Creek, Delaware County, Oklahoma, from February 2000 to September 2002, and experimentally stocked rainbow trout into the stream from November 2000 to March 2001 and November 2001 to March 2002. We used a combination of multivariate analyses to evaluate seasonal and habitat effects on native fish assemblages and to compare assemblage structure between prestocking, the first year of stocking, and the second year of stocking. Mesohabitat type significantly affected assemblage structure among years, whereas we did not detect an effect of season. We did not detect differences in assemblage structure among years in glide or riffle habitats. Native fish assemblage structure in pool habitats before rainbow trout introduction differed from assemblage structure in both the first and second year of stocking. Declines in seven species, including two native game fish (smallmouth bass Micropterus dolomieu and bluegill Lepomis machrochirus), contributed to assemblage dissimilarity in pool habitats between prestocking conditions and the second year of stocking. Our results indicate that stocking rainbow trout may cause local disruption in assemblage structure in pool habitats. ?? 2004 by the American Fisheries Society.
Fish assemblage structure and habitat associations in a large western river system
Smith, C.D.; Quist, Michael C.; Hardy, R. S.
2016-01-01
Longitudinal gradients of fish assemblage and habitat structure were investigated in the Kootenai River of northern Idaho. A total of 43 500-m river reaches was sampled repeatedly with several techniques (boat-mounted electrofishing, hoop nets and benthic trawls) in the summers of 2012 and 2013. Differences in habitat and fish assemblage structure were apparent along the longitudinal gradient of the Kootenai River. Habitat characteristics (e.g. depth, substrate composition and water velocity) were related to fish assemblage structure in three different geomorphic river sections. Upper river sections were characterized by native salmonids (e.g. mountain whitefish Prosopium williamsoni), whereas native cyprinids (peamouth Mylocheilus caurinus, northern pikeminnow Ptychocheilus oregonensis) and non-native fishes (pumpkinseed Lepomis gibbosus, yellow perch Perca flavescens) were common in the downstream section. Overall, a general pattern of species addition from upstream to downstream sections was discovered and is likely related to increased habitat complexity and additions of non-native species in downstream sections. Assemblage structure of the upper sections were similar, but were both dissimilar to the lower section of the Kootenai River. Species-specific hurdle regressions indicated the relationships among habitat characteristics and the predicted probability of occurrence and relative abundance varied by species. Understanding fish assemblage structure in relation to habitat could improve conservation efforts of rare fishes and improve management of coldwater river systems.
Ward, David L.
2012-01-01
Water in the Little Colorado River within Grand Canyon is naturally high in salt (NaCl), which is known to prohibit development of external fish parasites such as Ich (Ichthyophthirius multifiliis). The naturally high salinity (>0.3%) of the Little Colorado River at baseflow may be one factor allowing survival and persistence of larval and juvenile humpback chub (Gila cypha) and other native fishes in Grand Canyon. We compared salinity readings from the Little Colorado River to those reported in the literature as being effective at removing protozoan parasites from fish. In laboratory tests, 10 juvenile roundtail chub (Gila robusta; 61–90 mm TL) were randomly placed into each of 12, 37-L aquaria filled with freshwater, water obtained from the Little Colorado River (0.3% salinity), or freshwater with table salt added until the salinity reached 0.3%. Roundtail chub was used as a surrogate for humpback chub in this study because the species is not listed as endangered but is morphologically and ecologically similar to humpback chub. All roundtail chub infected with Ich recovered and survived when placed in water from the Little Colorado River or water with 0.3% salinity, but all experimental fish placed in freshwater died because of Ich infection. The naturally high salinity of the Little Colorado River at baseflow (0.22%–0.36%), appears sufficiently high to interrupt the life cycle of Ich and may allow increased survival of larval and juvenile humpback chub relative to other areas within Grand Canyon.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-20
... Reef Ecosystem Reserve Advisory Council: Native Hawaiian Representative, Ocean Related Tourism...-Related Tourism Representative (Ocean-Related Tourism). 3. One (1) Native Hawaiian (Elder) Alternate...-Large, Ocean-Related Tourism, Recreational Fishing, Research (3), Commercial Fishing, Education, State...
Fish and aquatic organisms [Chapter 9
John N. Rinne
2012-01-01
The UVR of central Arizona, from its source at Sullivan Lake to the mouth of Sycamore Creek, 60 km (38 mi) downstream, is rare among the Stateâs rivers because it still retains some of its native fish fauna. In 1994, six of the native fishes that were historically recorded in this reach of the Verde still occurred, along with at least seven nonnative species, and many...
Mueller, Gordon A.
2005-01-01
Mechanical predator removal programs have gained popularity in the United States and have benefited the recovery of several native trout and spring fish. These successes have been limited to headwater streams and small, isolated ponds or springs. Nevertheless, these same approaches are being applied to large river systems on the belief that any degree of predator removal will somehow benefit natives. This attitude is prevalent in the Colorado River mainstem where recovery and conservation programs are struggling to reverse the decline of four endangered fish species. Predator removal and prevention are major thrusts of that work but unfortunately, after 10 years and the removal of >1.5 million predators, we have yet to see a positive response from the native fish community. This leads to the obvious question: is mechanical removal or control in large (>100 cfs base flow) western streams technically or politically feasible? If not, recovery for some mainstem fishes may not be practical in the conventional sense, but require innovative management strategies to prevent their extirpation or possible extinction. This article examines (1) what has been attempted, (2) what has worked, and (3) what has not worked in the Colorado River mainstem and provides recommendations for future efforts in this critical management area.
Saiki, M.; Scoppettone, G.G.; Gadomski, D.; Becker, D.
2005-01-01
When thinking about plants and animals that inhabit hot arid lands of the southwestern U.S., fish are easily overlooked by most people. However, these desert lands often contain isolated springs or cienegas (a Spanish term referring to permanently saturated 'seep wetlands') and streams supporting native fishes that occur no where else in the world. These aquatic remnants from the last Ice Age have survived for thousands of years due to an amazing ability to tolerate harsh environmental conditions, especially extremely high water temperatures, high salinities, and unpredictable water flows.
Lopes, Taise M; Bailly, Dayani; Almeida, Bia A; Santos, Natália C L; Gimenez, Barbara C G; Landgraf, Guilherme O; Sales, Paulo C L; Lima-Ribeiro, Matheus S; Cassemiro, Fernanda A S; Rangel, Thiago F; Diniz-Filho, José A F; Agostinho, Angelo A; Gomes, Luiz C
2017-01-01
Climate change and species invasions interact in nature, disrupting biological communities. Based on this knowledge, we simultaneously assessed the effects of climate change on the native distribution of the Amazonian fish Colossoma macropomum as well as on its invasiveness across river basins of South America, using ecological niche modeling. We used six niche models within the ensemble forecast context to predict the geographical distribution of C. macropomum for the present time, 2050 and 2080. Given that this species has been continuously introduced into non-native South American basins by fish farming activities, we added the locations of C. macropomum farms into the modeling process to obtain a more realistic scenario of its invasive potential. Based on modelling outputs we mapped climate refuge areas at different times. Our results showed that a plenty of climatically suitable areas for the occurrence of C. macropomum occurrence are located outside the original basins at the present time and that its invasive potential is greatly amplified by fish farms. Simulations of future geographic ranges revealed drastic range contraction in the native region, implying concerns not only with respect to the species conservation but also from a socio-economic perspective since the species is a cornerstone of artisanal and commercial fisheries in the Amazon. Although the invasive potential is projected to decrease in the face of climate change, climate refugia will concentrate in Paraná River, Southeast Atlantic and East Atlantic basins, putting intense, negative pressures on the native fish fauna these regions. Our findings show that short and long-term management actions are required for: i) the conservation of natural stocks of C. macropomum in the Amazon, and ii) protecting native fish fauna in the climate refuges of the invaded regions.
Lopes, Taise M.; Bailly, Dayani; Almeida, Bia A.; Santos, Natália C. L.; Gimenez, Barbara C. G.; Landgraf, Guilherme O.; Sales, Paulo C. L.; Lima-Ribeiro, Matheus S.; Cassemiro, Fernanda A. S.; Rangel, Thiago F.; Diniz-Filho, José A. F.; Agostinho, Angelo A.; Gomes, Luiz C.
2017-01-01
Climate change and species invasions interact in nature, disrupting biological communities. Based on this knowledge, we simultaneously assessed the effects of climate change on the native distribution of the Amazonian fish Colossoma macropomum as well as on its invasiveness across river basins of South America, using ecological niche modeling. We used six niche models within the ensemble forecast context to predict the geographical distribution of C. macropomum for the present time, 2050 and 2080. Given that this species has been continuously introduced into non-native South American basins by fish farming activities, we added the locations of C. macropomum farms into the modeling process to obtain a more realistic scenario of its invasive potential. Based on modelling outputs we mapped climate refuge areas at different times. Our results showed that a plenty of climatically suitable areas for the occurrence of C. macropomum occurrence are located outside the original basins at the present time and that its invasive potential is greatly amplified by fish farms. Simulations of future geographic ranges revealed drastic range contraction in the native region, implying concerns not only with respect to the species conservation but also from a socio-economic perspective since the species is a cornerstone of artisanal and commercial fisheries in the Amazon. Although the invasive potential is projected to decrease in the face of climate change, climate refugia will concentrate in Paraná River, Southeast Atlantic and East Atlantic basins, putting intense, negative pressures on the native fish fauna these regions. Our findings show that short and long-term management actions are required for: i) the conservation of natural stocks of C. macropomum in the Amazon, and ii) protecting native fish fauna in the climate refuges of the invaded regions. PMID:28654663
Angermeier, Paul L.; Frimpong, Emmanuel A.
2011-01-01
The need for integrated and widely accessible sources of species traits data to facilitate studies of ecology, conservation, and management has motivated development of traits databases for various taxa. In spite of the increasing number of traits-based analyses of freshwater fishes in the United States, no consolidated database of traits of this group exists publicly, and much useful information on these species is documented only in obscure sources. The largely inaccessible and unconsolidated traits information makes large-scale analysis involving many fishes and/or traits particularly challenging. We have compiled a database of > 100 traits for 809 (731 native and 78 nonnative) fish species found in freshwaters of the conterminous United States, including 37 native families and 145 native genera. The database, named Fish Traits, contains information on four major categories of traits: (1) trophic ecology; (2) body size, reproductive ecology, and life history; (3) habitat preferences; and (4) salinity and temperature tolerances. Information on geographic distribution and conservation status was also compiled. The database enhances many opportunities for conducting research on fish species traits and constitutes the first step toward establishing a central repository for a continually expanding set of traits of North American fishes.
Dunham, J.B.; Young, M.; Gresswell, Robert E.; Rieman, B.
2003-01-01
Our limited understanding of the short and long-term effects of fire on fish contributes to considerable uncertainty in assessments of the risks and benefits of fire management alternatives. A primary concern among the many potential effects of fire is the effects of fire and fire management on persistence of native fish populations. Limited evidence suggests vulnerability of fish to fire is contingent upon the quality of affected habitats, the amount and distribution of habitat (habitat fragmentation), and habitat specificity of the species in question. Species with narrow habitat requirements in highly degraded and fragmented systems are likely to be most vulnerable to fire and fire-related disturbance. In addition to effects of fire on native fish, there are growing concerns about the effects of fire on nonnative fish invasions. The role of fire in facilitating invasions by nonnative fishes is unknown, but experience with other species suggests some forms of disturbance associated with fire may facilitate invasion. Management efforts to promote persistence of fishes in fire-prone landscapes can take the form of four basic alternatives: (1) pre-fire management; (2) post-fire management; (3) managing fire itself (e.g. fire fighting); and (4) monitoring and adaptive management. Among these alternatives, pre-fire management is likely to be most effective. Effective pre-fire management activities will address factors that may render fish populations more vulnerable to the effects of fire (e.g. habitat degradation, fragmentation, and nonnative species). Post-fire management is also potentially important, but suffers from being a reactive approach that may not address threats in time to avert them. Managing fire itself can be important in some contexts, but negative consequences for fish populations are possible (e.g. toxicity of fire fighting chemicals to fish). Monitoring and adaptive management can provide important new information for evaluating alternatives, but proper implementation is often hampered by inadequate study designs and inconsistent financial and institutional support. The challenge for providing better management guidelines will be to add solid empirical data and models to assess the relevance of emerging concepts and theories, and provide a sense of where and when fires pose significant risks and/or benefits to fishes.
Water guns affect abundance and behavior of bigheaded carp and native fish differently
Rivera, Jose; Glover, David C.; Kocovsky, Patrick; Garvey, James E.; Gaikowski, Mark; Jensen, Nathan R.; Adams, Ryan F.
2018-01-01
Water guns have shown the potential to repel nuisance aquatic organisms. This study examines the effects of exposure to a 1966.4 cm3 seismic water gun array (two guns) on the abundance and behavior of Bighead Carp Hypophthalmichthys nobilis, Silver Carp H. molitrix (collectively referred to as bigheaded carp) and native fishes (e.g., Smallmouth Buffalo Ictiobus bubalus). Water guns were deployed in a channel that connects the Illinois River to backwater quarry pits that contained a large transient population of bigheaded carp. To evaluate the effect of water guns, mobile side-looking split-beam hydroacoustic surveys were conducted before, during and between replicated water gun firing periods. Water guns did not affect abundance of bigheaded carp, but abundance of native fish detected during the firing treatment was 43 and 34% lower than the control and water guns off treatments, respectively. The proximity of bigheaded carp to the water gun array was similar between the water guns on and water guns off treatments. In contrast, the closest detected native fish were detected farther from the water guns during the water guns on treatment (mean ± SE, 32.38 ± 3.32 m) than during the water guns off treatment (15.04 ± 1.59 m). The water gun array had a greater impact on native fish species than on bigheaded carp. Caution should be taken to the extrapolation of these results to other fish species and to fish exposed to water guns in different environments (e.g., reduced shoreline interaction) or exposure to a larger array of water guns, or for use of water guns for purposes other than a barrier.
EPA's Western Ecology Division is undertaking research addressing catchment-scale dynamics of freshwater habitat productivity for native fishes. Through partnerships with state and federal agencies and private landowners, current field efforts focus on linkages among stream chemi...
Relations between introduced fish and environmental conditions at large geographic scales
Meador, M.R.; Brown, L.R.; Short, T.
2003-01-01
Data collected from 20 major river basins between 1993 and 1995 as part of the US Geological Survey's (USGS) National Water-Quality Assessment (NAWQA) Program were analyzed to assess patterns in introduced and native fish species richness and abundance relative to watershed characteristics and stream physicochemistry. Sites (N = 157) were divided into three regions-northeast, southeast, and west- to account for major longitudinal differences in precipitation/runoff and latitudinal limits of glaciation that affect zoogeographic patterns in fish communities. Common carp (Cyprinus carpio) and largemouth bass (Micropterus salmoides) were the most frequently collected introduced fish species across all river basins combined. Based on the percentage of introduced fish species, the fish communities most altered by the presence of introduced fish occurred in the western and northeastern parts of the US. Native fish species richness was not an indicator of introduced fish species richness for any of the three regions. However, in the west, introduced fish species richness was an indicator of total fish species richness and the abundance of introduced fish was negatively related to native fish species richness. Some relations between introduced fish species and environmental conditions were common between regions. Increased introduced fish species richness was related to increased population density in the northeast and southeast; increased total nitrogen in the northeast and west; and increased total phosphorous and water temperature in the southeast and west. These results suggest that introduced fish species tend to be associated with disturbance at large geographic scales, though specific relations may vary regionally. ?? 2003 Elsevier Science Ltd. All rights reserved.
Non-native species impacts on pond occupancy by an anuran
Adams, Michael J.; Pearl, Christopher A.; Galvan, Stephanie; McCreary, Brome
2011-01-01
Non-native fish and bullfrogs (Lithobates catesbeianus; Rana catesbeiana) are frequently cited as factors contributing to the decline of ranid frogs in the western United States (Bradford 2005). This hypothesis is supported by studies showing competition with or predation by these introduced species (Kupferberg 1997, Kiesecker and Blaustein 1998, Lawler et al. 1999, Knapp et al. 2001) and studies suggesting a deficit of native frogs at sites occupied by bullfrogs or game fish (Hammerson 1982, Schwalbe and Rosen 1988, Fisher and Shaffer 1996, Adams 1999). Conversely, other studies failed to find a negative association between native ranids and bullfrogs and point out that presence of non-native species correlates with habitat alterations that could also contribute to declines of native species (Hayes and Jennings 1986; Adams 1999, 2000; Pearl et al. 2005). A criticism of these studies is that they may not detect an effect of non-native species if the process of displacement is at an early stage. We are not aware of any studies that have monitored a set of native frog populations to determine if non-native species predict population losses. Our objective was to study site occupancy trends in relation to non-native species for northern red-legged frogs (Rana aurora) on federal lands in the southern Willamette Valley, Oregon. We conducted a 5-yr monitoring study to answer the following questions about the status and trends of the northern red-legged frog: 1) What is the rate of local extinction (how often is a site that is occupied in year t unoccupied in year t+1) and what factors predict variation in local extinction? and 2) What is the rate of colonization (how often is a site that is unoccupied in year t occupied in year t+1) and what factors predict variation in colonization? The factors we hypothesized for local extinction were: 1) bullfrog presence, 2) bullfrogs mediated by wetland vegetation, 3) non-native fish (Centrarchidae), 4) non-native fish mediated by wetland vegetation, 5) extent of emergent vegetation, 6) extent of riparian forest, and 7) a combined effect of bullfrogs and fish. The factors that we hypothesized for colonization were: 1) the extent of human influence in the surrounding landscape, 2) riparian forest, and 3) wetland size.
Kalb, Bradley W.; Caldwell, Colleen A.
2014-01-01
Rio Grande Cutthroat trout Oncorhynchus clarkii virginalis (RGCT) represents the most southern subspecies of cutthroat trout, endemic to Rio Grande, Canadian, and Pecos basins of New Mexico and southern Colorado. The subspecies currently occupies less than 12% of its historic range. The Mescalero Apache Tribe has partnered with U.S. Geological Survey-New Mexico Cooperative Fish and Wildlife Research Unit, New Mexico State University, U.S. Fish and Wildlife Service, and New Mexico Department of Game and Fish to meet mutually shared goals of restoring and maintaining a Pecos strain of RGCT to Tribal lands. The goal of this project was to assess the suitability of the Rio Ruidoso within the Mescalero Apache Reservation to support a self-sustaining RGCT population by conducting a systematic and comprehensive survey. We conducted three surveys (fall 2010, spring 2011 and 2012) to characterize water quality, macroinvertebrate assemblages, fish communities, and physical habitat (stream size, channel gradient, channel substrate, habitat complexity, riparian vegetation cover and structure, migration barriers to movement).Seven-100 m reaches throughout three major tributaries of the Rio Ruidoso within the Tribal lands were sampled during baseflow conditions October 2010, May 2011, and June 2012. Despite the onset of severe drought in 2011, water quality, physical habitat, and fish populations revealed that the Rio Ruidoso and its three tributaries would most likely support a self-sustaining RGCT population. Pools were abundant (mean, 8.9 pools/100 m), instream woody debris was present (range, 3.8-45.6 pieces/100 m), and instream dataloggers revealed daily maximum stream temperatures rarely exceeded criteria established in New Mexico for coldwater fishes, however, presence of frazil and anchor ice may limit fish distribution in the winter. Aquatic macroinvertebrate samples revealed a community of benthic invertebrates reflective of high quality cool to cold water. Overall densities of brown trout, rainbow trout and brook trout were high (overall mean, 0.23 fish/m2) and in relatively good condition (range of mean relative weight, 84-117).Should the Mescalero Apache Tribe decide to introduce RGCT, prior to chemical treatment, a barrier placed below the confluence of Middle and South forks of the Rio Ruidoso would create approximately 12 km of perennial flow and help protect against invasion of non-native fishes. The North Fork of the Rio Ruidoso is not a good candidate for reintroduction because of easy access by the public to reintroduce non-native fishes into the watershed. Lastly, an annual, long-term monitoring program of RGCT would help document that there was no subsequent incursion of non-native fishes.
Li, Xiao-Yan; Peng, Ming-Chun; Dong, Shi-Kui; Liu, Shi-Liang; Li, Jin-Peng; Yang, Zhi-Feng
2013-02-01
An investigation was conducted on the phytoplankton, zooplankton, and fish at 8 sampling sections in the Manwan Reservoir before and after the construction of Xiaowan Hydropower Dam. The modified ESHIPPO model was applied to study the changes of the featured aquatic species, including endangered species, endemic specie, peis resource species, and native fish, aimed to make an ecological risk assessment of the dam construction on the aquatic species. The dam construction had definite ecological risk on the aquatic species, especially the endemic fish, in Langcang River, due to the changes of hydrological conditions. The endemic species including Bangia atropurpurea, Lemanea sinica, Prasiola sp., Attheyella yunnanensis, and Neutrodiaptomus mariadvigae were at high ecological risk, and thus, besides monitoring, protection measures were needed to be taken to lower the possibility of the species extinction. The widely distributed species of phytoplankton and zooplankton were at medium ecological risk, and protection measures besides monitoring should be prepared. Twelve kinds of native fish, including Barbodes huangchuchieni, Sinilabeo laticeps, Racoma lantsangensis, Racoma lissolabiatus, Paracobitis anguillioides, Schistura latifasciata, Botia nigrolineata, Vanmanenia striata, Homaloptera yunnanensis, Platytropius longianlis, Glyptothorax zanaensis, and Pseudecheneis immaculate, were at high ecological risk, and protection measures needed to be developed to prevent the possibility of the species loss and extinction.
Scoppettone, G.G.; Johnson, D.M.; Hereford, M.E.; Rissler, Peter; Fabes, Mark; Salgado, Antonio; Shea, Sean
2012-01-01
Habitat restoration that favors native species can help control non-native species (McShane and others, 2004; Scoppettone and others, 2005; Kennedy and others, 2006). Restoration of Carson Slough and its tributaries present an opportunity to promote habitat types that favor native species over non-natives. Historically, the majority of Ash Meadows spring systems were tributaries to Carson Slough. In 2007 and 2008, a survey of Ash Meadows spring systems was conducted to generate baseline information on the distribution of fishes throughout AMNWR (Scoppettone and others, 2011b). In this study, we conducted a follow-up survey with emphasis on upper Carson Slough. This permitted us to gauge the early effects of spring system restoration on fish populations and to generate further baseline data relevant to future restoration efforts.
Effects of capture by trammel net on Colorado River native fishes
Hunt, Teresa A.; Ward, David L.; Propper, Catherine R.; Gibb, Alice C.
2012-01-01
Trammel nets are commonly used to sample rare fishes; however, little research has assessed delayed mortality associated with this capture technique. We conducted laboratory experiments to evaluate the effects of capture by trammel net on bonytail Gila elegans, razorback sucker Xyrauchen texanus, and roundtail chub Gila robusta, at 15, 20, and 25uC. Fish (139–288 mm total length) were entangled in a trammel net for 2 h or captured by seine net and then monitored for mortality for at least 14 d. Blood samples were collected immediately after capture, and plasma cortisol levels were quantified as an index of capture-related stress. The cortisol response varied by species, but mean cortisol levels were higher for fish captured by trammel netting (295.9 ng/mL) relative to fish captured by seine netting (215.8 ng/mL). Only one fish (of 550) died during capture and handling, but 42% of the trammel-netted fish and 11% of the seine-netted fish died within 14 d after capture. In general, mortality after capture by trammel net increased with increased water temperature and at 25uC was 88% for bonytail, 94% for razorback sucker, and 25% for roundtail chub. Delayed mortality of wild-caught fish captured by trammel net has the potential to be high, at least under some circumstances. We suggest that sampling frequency, timing of sampling (relative to reproductive cycles), and water temperature all be considered carefully when using trammel nets to sample diminished populations of imperiled native fishes.
Trophic relations of introduced flathead catfish in an atlantic river
Baumann, Jessica R.; Kwak, Thomas J.
2011-01-01
The flathead catfish Pylodictis olivaris is a large piscivore that is native to the Mississippi and Rio Grande river drainages but that has been widely introduced across the United States. River ecologists and fisheries managers are concerned about introduced flathead catfish populations because of the negative impacts on native fish communities or imperiled species associated with direct predation and indirect competition from this apex predator. We studied the trophic relations of introduced flathead catfish in an Atlantic river to further understand the effects on native fish communities. Crayfish (Astacidea) occurred most frequently in the flathead catfish diet, while sunfish Lepomis spp. comprised the greatest percentage by weight. Neither of two sympatric imperiled fish species (the federally endangered Cape Fear shiner Notropis mekistocholas and the Carolina redhorse Moxostoma sp., a federal species of concern) was found in any diet sample. An ontogenetic shift in diet was evident when flathead catfish reached about 300 mm, and length significantly explained the variation in the percent composition by weight of sunfish and darters Etheostoma and Percina spp. Flathead catfish showed positive prey selectivity for taxa that occupied similar benthic microhabitat, highlighting the importance of opportunistic feeding and prey encounter rates. Flathead catfish displayed a highly variable diel feeding chronology during July, when they had a mean stomach fullness of 0.32%, but then showed a single midday feeding peak during August (mean fullness = 0.52%). The gastric evacuation rate increased between July (0.40/h) and August (0.59/h), as did daily ration, which more than doubled between the 2 months (3.06% versus 7.37%). Our findings increase the understanding of introduced flathead catfish trophic relations and the degree of vulnerability among prey taxa, which resource managers may consider in fisheries management and conservation of native fish populations and imperiled species.
Vulnerability of freshwater native biodiversity to non-native ...
Background/Question/Methods Non-native species pose one of the greatest threats to native biodiversity. The literature provides plentiful empirical and anecdotal evidence of this phenomenon; however, such evidence is limited to local or regional scales. Employing geospatial analyses, we investigate the potential threat of non-native species to threatened and endangered aquatic animal taxa inhabiting unprotected areas across the continental US. We compiled distribution information from existing publicly available databases at the watershed scale (12-digit hydrologic unit code). We mapped non-native aquatic plant and animal species richness, and an index of cumulative invasion pressure, which weights non-native richness by the time since invasion of each species. These distributions were compared to the distributions of native aquatic taxa (fish, amphibians, mollusks, and decapods) from the International Union for the Conservation of Nature (IUCN) database. We mapped the proportion of species listed by IUCN as threatened and endangered, and a species rarity index per watershed. An overlay analysis identified watersheds experiencing high pressure from non-native species and also containing high proportions of threatened and endangered species or exhibiting high species rarity. Conservation priorities were identified by generating priority indices from these overlays and mapping them relative to the distribution of protected areas across the US. Results/Conclusion
Comparison of burbot populations across adjacent native and introduced ranges
Walters, Annika W.; Mandeville, Elizabeth G.; Saunders, W. Carl; Gerrity, Paul C.; Skorupski, Joseph A.; Underwood, Zachary E.; Gardunio, Eric I.
2017-01-01
Introduced species are a threat to biodiversity. Burbot, Lota lota, a fish native to the Wind River Drainage, Wyoming and a species of conservation concern, have been introduced into the nearby Green River Drainage, Wyoming, where they are having negative effects on native fish species. We compared these native and introduced burbot populations to evaluate potential mechanisms that could be leading to introduction success. We examined genetic ancestry, physical habitat characteristics, community composition, and burbot abundance, relative weight, and size structure between the native and introduced range to elucidate potential differences. The origin of introduced burbot in Flaming Gorge Reservoir is most likely Boysen Reservoir and several nearby river populations in the native Wind River Drainage. Burbot populations did not show consistent differences in abundance, size structure, and relative weight between drainages, though Fontenelle Reservoir, in the introduced drainage, had the largest burbot. There were also limited environmental and community composition differences, though reservoirs in the introduced drainage had lower species richness and a higher percentage of non-native fish species than the reservoir in the native drainage. Burbot introduction in the Green River Drainage is likely an example of reservoir construction creating habitat with suitable environmental conditions to allow a southwards range expansion of this cold-water species. An understanding of the factors driving introduction success can allow better management of species, both in their introduced and native range.
Changes in the fish fauna of the Kissimmee River basin, peninsular Florida: Nonnative additions
Nico, L.G.
2005-01-01
Recent decades have seen substantial changes in fish assemblages in rivers of peninsular Florida. The most striking change has involved the addition of nonnative fishes, including taxa from Asia, Africa, and Central and South America. I review recent and historical records of fishes occurring in the Kissimmee River basin (7,800 km2), a low-gradient drainage with 47 extant native fishes (one possibly the result of an early transplant), at least 7 foreign fishes (most of which are widely established), and a stocked hybrid. Kissimmee assemblages include fewer marine fishes than the nearby Peace and Caloosahatchee rivers, and fewer introduced foreign fishes than south Florida canals. Fish assemblages of the Kissimmee and other subtropical Florida rivers are dynamic, due to new introductions, range expansions of nonnative fishes already present, and periodic declines in nonnative fish populations during occasional harsh winters. The addition, dispersal, and abundance of nonnative fishes in the basin is linked to many factors, including habitat disturbance, a subtropical climate, and the fact that the basin is centrally located in a region where drainage boundaries are blurred and introductions of foreign fishes commonplace. The first appearance of foreign fishes in the basin coincided with the complete channelization of the Kissimmee River in the 1970s. Although not a causal factor, artificial waterways connecting the upper lakes and channelization of the Kissimmee River have facilitated dispersal. With one possible exception, there have been no basin-wide losses of native fishes. When assessing change in peninsular Florida waters, extinction or extirpation of fishes appears to be a poor measure of impact. No endemic species are known from peninsular Florida (although some endemic subspecies have been noted). Most native freshwater fishes are themselves descended from recent invaders that reached the peninsula from the main continent. These invasions likely were associated with major fluctuations in sea level since the original mid-Oligocene emergence of the Florida Platform. As opportunistic invaders, most native freshwater fishes in peninsular Florida are resilient, widespread, and common. At this early stage, it is not possible to predict the long-term consequences caused by the introduction of foreign fishes. We know a few details about the unusual trophic roles and other aspects of the life histories of certain nonnatives. Still, the ecological outcome may take decades to unfold.
Native salamanders and introduced fish: Changing the nature of mountain lakes and ponds
Larson, Gary L.; Hoffman, Robert L.
2003-01-01
During the last century, many fishless mountain lakes and ponds in the Pacific Northwest were stocked with non-native fish, such as brook trout, for recreational purposes. These introduced fish replaced long-toed and northwestern salamander larvae as the top aquatic vertebrate predator by preying on salamander larvae. This predatory interaction has been shown to reduce the abundances of larval salamander populations. We conducted studies in two national parks to assess the abundances of salamander larvae in lakes with and without introduced fish. These studies suggest that the two salamander species were affected quite differently by the presence of introduced fish because of different life-history traits and different distributions of salamanders and fish within each park.
Fish fertilizer: a native north american practice?
Ceci, L
1975-04-04
The belief that the use of fish fertilizers originated among North American Indians, and was communicated as such by Squanto to the Plymouth settlers, has achieved the status of folklore and is therefore difficult to challenge. However, examination of the documentary evidence of Squanto's history and of native cultivation practices, and a cultural analysis of the implications of the use of fish fertilizer, have produced complementary lines of evidence. This evidence indicates that widely held beliefs about the "manner of the Indians" should be revised: Squanto's advice at Plymouth is probably best viewed as an interesting example of culture contact, one in which a native "culture-bearer" conveyed a technological idea from one group of Europeans to another.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abernethy, C.S.
1994-09-01
A program to monitor the salmon and steelhead (Oncorhynchus spp.) fishery in the lower Columbia River (Zone 6 fishery) was initiated in 1991 to respond to questions and comments frequently made by Native Americans at public meetings. Native Americans were concerned that the quality of the Columbia River had deteriorated and that the poor environmental conditions had affected the health and quality of fish they relied on for subsistence, ceremonial, religious, and commercial purposes. They also feared that eating contaminated fish might endanger the health of their children and future generations. Operations at the Hanford Site were listed as onemore » of many causes of the deteriorating environment. Fisheries pathologists concluded that most of the external symptoms on fish were related to bacterial infection of gill net abrasions and pre-spawning trauma, and were not caused by pollution or contamination of the Columbia River. The pathologists also stated that consumption of the fish posed no threat to human consumers.« less
1981-10-02
the factors controlling their distribution within the Leland Harris complex. Design of studies to examine critical areas in such a fashion will 5...Dewatering, channelizing, construction of cement-lined ditches, damming, and establishment of non -native Species of fishes or mollusks, reduce...population. The convict cichlid and mexican molly shared dominance in the fish fauna. Clearly, the non -native fish and the introduced snail, Melanoides
Ilhéu, Maria; Matono, Paula; Bernardo, João Manuel
2014-01-01
Invasive species are regarded as a biological pressure to natural aquatic communities. Understanding the factors promoting successful invasions is of great conceptual and practical importance. From a practical point of view, it should help to prevent future invasions and to mitigate the effects of recent invaders through early detection and prioritization of management measures. This study aims to identify the environmental determinants of fish invasions in Mediterranean-climate rivers and evaluate the relative importance of natural and human drivers. Fish communities were sampled in 182 undisturbed and 198 disturbed sites by human activities, belonging to 12 river types defined for continental Portugal within the implementation of the European Union's Water Framework Directive. Pumpkinseed sunfish, Lepomis gibbosus (L.), and mosquitofish, Gambusia holbrooki (Girard), were the most abundant non-native species (NNS) in the southern river types whereas the Iberian gudgeon, Gobio lozanoi Doadrio and Madeira, was the dominant NNS in the north/centre. Small northern mountain streams showed null or low frequency of occurrence and abundance of NNS, while southern lowland river types with medium and large drainage areas presented the highest values. The occurrence of NNS was significantly lower in undisturbed sites and the highest density of NNS was associated with high human pressure. Results from variance partitioning showed that natural environmental factors determine the distribution of the most abundant NNS while the increase in their abundance and success is explained mainly by human-induced disturbance factors. This study stresses the high vulnerability of the warm water lowland river types to non-native fish invasions, which is amplified by human-induced degradation. PMID:25372284
Evaluating effects of fish stocking on amphibian populations in wilderness lakes
David S. Pilliod; Charles R. Peterson
2000-01-01
To balance wilderness lake use between recreational fisheries and protected habitat for native species, managers need to understand how stocking non-native predaceous fish affects amphibian populations within a landscape. The goal of this paper is to help managers design and conduct studies that will provide such information. Desirable study characteristics include...
George, Scott D.; Baldigo, Barry P.; Wells, Scott M
2016-01-01
The Mohawk River and New York State Barge Canal run together as a series of permanent and temporary impoundments for most of the distance between Rome and Albany, New York. The downstream or lower section is composed of two permanent impoundments, the middle section of a series of temporary (seasonal) impoundments, and the upper section of a series of permanent impoundments. In the middle section, movable dams are lifted from the water during winter and the wetted surface area decreases by 36–56%. We used boat electrofishing during spring 2014 and 2015 to compare the relative abundance of fish populations and the composition of fish assemblages between the permanently and seasonally impounded sections of the Barge Canal and to infer the effects of the two flow management practices. A total of 3,264 individuals from 38 species were captured, and total catch per unit effort (CPUE) ranged from 46.0 to 134.7 fish/h at sites in the seasonally impounded section, compared with 140.0–342.0 fish/h in the permanent lower section and 89.0–282.0 fish/h in the permanent upper section. The amount of drawdown explained 55% of the variation in total CPUE and was a highly significant predictor variable. Mean total CPUE in the seasonally impounded section was significantly lower (by about 50%) than that in either permanently impounded section, and the assemblage composition differed significantly between sections. The relative abundance of many lentic species was markedly lower in the seasonally impounded section, while the relative abundance of several native cyprinids and the percentage of individuals belonging to species that are native to the watershed was greater in this section. Overall, these findings suggest that winter dam removal in impounded rivers may reduce the abundance of fish but may also create more natural riverine conditions that favor some native species.
Pearl, Christopher A.; Adams, Michael J.; Leuthold, N.; Bury, R. Bruce
2005-01-01
Despite concern about the conservation status of amphibians in western North America, few field studies have documented occurrence patterns of amphibians relative to potential stressors. We surveyed wetland fauna in Oregon's Willamette Valley and used an information theoretic approach (AIC) to rank the associations between native amphibian breeding occurrence and wetland characteristics, non-native aquatic predators, and landscape characteristics in a mixed urban-agricultural landscape. Best predictors varied among the five native amphibians and were generally consistent with life history differences. Pacific tree frog (Pseudacris regilla) and long-toed salamander (Ambystoma macrodactylum) occurrence was best predicted by the absence of non-native fish. Northern red-legged frog (Rana a. aurora) and northwestern salamander (Ambystoma gracile) were most strongly related to wetland vegetative characteristics. The occurrence of rough-skinned newts (Taricha granulosa), a migratory species that makes extensive use of terrestrial habitats, was best predicted by greater forest cover within 1 km. The absence of non-native fish was a strong predictor of occurrence for four of the five native species. In contrast, amphibians were not strongly related to native fish presence. We found little evidence supporting negative effects of the presence of breeding populations of bullfrog (Rana catesbeiana) on any native species. Only the two Ambystoma salamanders were associated with wetland permanence. Northwestern salamanders (which usually have a multi-year larval stage) were associated with permanent waters, while long-toed salamanders were associated with temporary wetlands. Although all the species make some use of upland habitats, only one (rough-skinned newt) was strongly associated with surrounding landscape conditions. Instead, our analysis suggests that within-wetland characteristics best predict amphibian occurrence in this region. We recommend that wetland preservation and mitigation efforts concentrate on sites lacking non-native fish for the conservation of native amphibians in the Willamette Valley and other western lowlands.
Velázquez-Velázquez, Ernesto; González-Solís, David; Salgado-Maldonado, Guillermo
2011-09-01
The Asian fish tapeworm, Bothriocephalus acheilognathi, has been considered one of the most dangerous parasites for cultured carp and a risk for native freshwater fish populations worldwide. This cestode is highly pathogenic for fishes especially fry. In this paper we record B. acheilognathi parasitizing the endangered and endemic freshwater fish Profundulus hildebrandi from the endorheic basin of San Crist6bal de las Casas, Chiapas, Mexico. B. acheilognathi was recorded from 10 of the 11 sampled localities, with high values of prevalence (> 60%) and mean abundance (> 4.50). The infection was persistent all through the year; gravid cestodes were recorded in all samples. It is assumed that B. acheilognathi entered to this area through the introduction of common carp Cyprinus carpio, for aquacultural purposes. The data presented in this paper document the successful introduction, colonization and establishment of this alien species into the endangered P. hildebrandi.
A trial of two trouts: Comparing the impacts of rainbow and brown trout on a native galaxiid
Young, K.A.; Dunham, J.B.; Stephenson, J.F.; Terreau, A.; Thailly, A.F.; Gajardo, G.; de Leaniz, C. G.
2010-01-01
Rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta are the world's two most widespread exotic fishes, dominate the fish communities of most cold-temperate waters in the southern hemisphere and are implicated in the decline and extirpation of native fish species. Here, we provide the first direct comparison of the impacts of rainbow and brown trout on populations of a native fish by quantifying three components of exotic species impact: range, abundance and effect. We surveyed 54 small streams on the island of Chilo?? in Chilean Patagonia and found that the rainbow trout has colonized significantly more streams and has a wider geographic range than brown trout. The two species had similar post-yearling abundances in allopatry and sympatry, and their abundances depended similarly on reach-level variation in the physical habitat. The species appeared to have dramatically different effects on native drift-feeding Aplochiton spp., which were virtually absent from streams invaded by brown trout but shared a broad sympatric range with rainbow trout. Within this range, the species' post-yearling abundances varied independently before and after controlling for variation in the physical habitat. In the north of the island, Aplochiton spp. inhabited streams uninvaded by exotic trouts. Our results provide a context for investigating the mechanisms responsible for apparent differences in rainbow and brown trout invasion biology and can help inform conservation strategies for native fishes in Chilo?? and elsewhere. ?? 2010 The Authors. Journal compilation ?? 2010 The Zoological Society of London.
Kwak, T.J.; Pine, William E.; Waters, D.S.
2006-01-01
Knowledge of individual growth and mortality rates of an introduced fish population is required to determine the success and degree of establishment as well as to predict the fish's impact on native fauna. The age and growth of flathead catfish Pylodictis olivaris have been studied extensively in the species' native and introduced ranges, and estimates have varied widely. We quantified individual growth rates and age structure of three introduced flathead catfish populations in North Carolina's Atlantic slope rivers using sagittal otoliths, determined trends in growth rates over time, compared these estimates among rivers in native and introduced ranges, and determined total mortality rates for each population. Growth was significantly faster in the Northeast Cape Fear River (NECFR) than in the Lumber and Neuse rivers. Fish in the NECFR grew to a total length of 700 mm by age 7, whereas fish in the Neuse and Lumber river populations reached this length by 8 and 10 years, respectively. The growth rates of fish in all three rivers were consistently higher than those of native riverine populations, similar to those of native reservoir populations, and slower than those of other introduced riverine populations. In general, recent cohorts (1998-2001 year-classes) in these three rivers exhibited slower growth among all ages than did cohorts previous to the 1998 year-class. The annual total mortality rate was similar among the three rivers, ranging from 0.16 to 0.20. These mortality estimates are considerably lower than those from the Missouri and Mississippi rivers, suggesting relatively low fishing mortality for these introduced populations. Overall, flathead catfish populations in reservoirs grow faster than those in rivers, the growth rates of introduced populations exceed those of native populations, and eastern United States populations grow faster than those in western states. Such trends constitute critical information for understanding and managing local populations.
Small estuarine fishes feed on large trematode cercariae: Lab and field investigations
Kaplan, A.T.; Rebhal, S.; Lafferty, K.D.; Kuris, A.M.
2009-01-01
In aquatic ecosystems, dense populations of snails can shed millions of digenean trematode cercariae every day. These short-lived, free-living larvae are rich in energy and present a potential resource for consumers. We investigated whether estuarine fishes eat cercariae shed by trematodes of the estuarine snail Cerithidea californica. In aquaria we presented cercariae from 10 native trematode species to 6 species of native estuarine fishes. Many of these fishes readily engorged on cercariae. To determine if fishes ate cercariae in the field, we collected the most common fish species, Fundulus parvipinnis (California killifish), from shallow water on rising tides when snails shed cercariae. Of 61 killifish, 3 had recognizable cercariae in their gut. Because cercariae are common in this estuary, they could be frequent sources of energy for small fishes. In turn, predation on cercariae by fishes (and other predators) could also reduce the transmission success of trematodes. ?? 2009 American Society of Parasitologists.
Genetic Structure of Pacific Trout at the Extreme Southern End of Their Native Range
Abadía-Cardoso, Alicia; Garza, John Carlos; Mayden, Richard L.; García de León, Francisco Javier
2015-01-01
Salmonid fishes are cold water piscivores with a native distribution spanning nearly the entire temperate and subarctic northern hemisphere. Trout in the genus Oncorhynchus are the most widespread salmonid fishes and are among the most important fish species in the world, due to their extensive use in aquaculture and valuable fisheries. Trout that inhabit northwestern Mexico are the southernmost native salmonid populations in the world, and the least studied in North America. They are unfortunately also facing threats to their continued existence. Previous work has described one endemic species, the Mexican golden trout (O. chrysogaster), and one endemic subspecies, Nelson’s trout (O. mykiss nelsoni), in Mexico, but previous work indicated that there is vastly more biodiversity in this group than formally described. Here we conducted a comprehensive genetic analysis of this important group of fishes using novel genetic markers and techniques to elucidate the biodiversity of trout inhabiting northwestern Mexico, examine genetic population structure of Mexican trout and their relationships to other species of Pacific trout, and measure introgression from non-native hatchery rainbow trout. We confirmed substantial genetic diversity and extremely strong genetic differentiation present in the Mexican trout complex, not only between basins but also between some locations within basins, with at least four species-level taxa present. We also revealed significant divergence between Mexican trout and other trout species and found that introgression from non-native rainbow trout is present but limited, and that the genetic integrity of native trout is still maintained in most locations. This information will help to guide effective conservation strategies for this important group of fishes. PMID:26509445
Melis, Theodore S.; Hamill, John F.; Bennett, Glenn E.; Coggins,, Lewis G.; Grams, Paul E.; Kennedy, Theodore A.; Kubly, Dennis M.; Ralston, Barbara E.
2010-01-01
Since the 1980s, four major science and restoration programs have been developed for the Colorado River Basin to address primarily the conservation of native fish and other wildlife pursuant to the Endangered Species Act (ESA): (1) Recovery Implementation Program for Endangered Fish Species in the Upper Colorado River Basin (commonly called the Upper Colorado River Endangered Fish Recovery Program) (1988); (2) San Juan River Basin Recovery Implementation Program (1992); (3) Glen Canyon Dam Adaptive Management Program (1997); and (4) Lower Colorado River Multi-Species Conservation Program (2005). Today, these four programs, the efforts of which span the length of the Colorado River, have an increasingly important influence on water management and resource conservation in the basin. The four efforts involve scores of State, Federal, and local agencies; Native American Tribes; and diverse stakeholder representatives. The programs have many commonalities, including similar and overlapping goals and objectives; comparable resources and threats to those resources; and common monitoring, research, and restoration strategies. In spite of their commonalities, until recently there had been no formal opportunity for information exchange among the programs. To address this situation, the U.S. Geological Survey (USGS) worked in coordination with the four programs and numerous Federal and State agencies to organize the first Colorado River Basin Science and Resource Management Symposium, which took place in Scottsdale, AZ, in November 2008. The symposium's primary purpose was to promote an exchange of information on research and management activities related to the restoration and conservation of the Colorado River and its major tributaries. A total of 283 managers, scientists, and stakeholders attended the 3-day symposium, which included 87 presentations and 27 posters. The symposium featured plenary talks by experts on a variety of topics, including overviews of the four restoration programs, water-management actions aimed at restoring native fish habitat, climate change, assessments of the status of native and nonnative fish populations, and Native American perspectives. Intermixed with plenary talks were four concurrent technical sessions that addressed the following important topics: (1) effects of dam and reservoir operations on downstream physical and biological resources; (2) native fish propagation and genetic management and associated challenges in co-managing native and nonnative fish in the Colorado River; (3) monitoring program design, case studies, and links to management; and (4) riparian system restoration, monitoring, and exotic species control efforts.
Bunnell, D.B.; Madenjian, C.P.; Claramunt, R.M.
2006-01-01
We used our long-term annual bottom trawl survey (1973–2004) in Lake Michigan to reveal the response of the native fish community to the biological control of a dominant exotic fish, alewife (Alosa pseudoharengus), as well as to changes in total phosphorus and salmonine biomass. Through nonmetric multidimensional scaling, we documented a 1970s community largely dominated by alewife, and then a shift to a community dominated by several native species during the 1980s through 1990s, when alewife remained at relatively low levels. We argue that the recovery of burbot (Lota lota), deepwater sculpin (Myoxocephalus thompsonii), and yellow perch (Perca flavescens) was partially or fully aided by the alewife reduction. We argue that changes in phosphorus or salmonines were not directly related to abundance increases of native species. An additional community shift occurred during 1999–2004, which coincided with a reduction in species richness and total fish biomass in our trawl. The mechanisms underlying this latest shift may be related to reductions in nutrients, but further research is required. The restoration of the native fish community has been incomplete, however, as emerald shiner (Notropis atherinioides), cisco (Coregonus artedii), and lake trout (Salvelinus namaycush) have yet to demonstrate recovery.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hlohowskyj, I.; Hayse, J.W.
1995-09-01
Aerial videography and modeling were used to evaluate the impacts of four hydropower operational scenarios at Flaming Gorge Dam, Utah, on trout and native fishes in the Green River, Utah and Colorado. The four operational scenarios studied were year-round high fluctuations, seasonally adjusted high fluctuations, seasonally adjusted moderate fluctuations, and seasonally adjusted steady flows. Impacts on trout were evaluated by examining differences among scenarios in the areas of inundated substrates that serve as spawning and feeding habitat. All scenarios would provide at least 23 acres per mile of habitat for spawning and food production; seasonally adjusted operations would provide additionalmore » areas during periods of sustained high release. Seasonally adjusted high fluctuations would increase inundated areas by 12 to 26% for a short period in winter and spring, but food production and reproduction would not be expected to increase. Seasonally adjusted moderate fluctuations and steady flows would produce similar increases in area, but the longer period of inundation could also result in increased food production and provide additional spawning sites for trout. Impacts on native fishes were assessed by examining daily changes in backwater nursery areas. Compared with year-round high fluctuations, the daily changes in backwater area would decrease by about 47, 89, and 100% under the seasonally adjusted high fluctuation, moderate fluctuation, and steady flow scenarios, respectively. Similarly, daily stage fluctuations during the nursery period would decrease by 72, 89, and 100% under the seasonally adjusted high fluctuation, moderate fluctuation, and steady flow scenarios, respectively. These reductions in daily fluctuations in backwater area and stage would improve conditions in nursery habitats and could in turn improve recruitment and overwinter survival. Introduced fish species could also benefit from the seasonally adjusted operational scenarios.« less
Olinger, Lauren K; Heidmann, Sarah L; Durdall, Allie N; Howe, Colin; Ramseyer, Tanya; Thomas, Sara G; Lasseigne, Danielle N; Brown, Elizabeth J; Cassell, John S; Donihe, Michele M; Duffing Romero, Mareike D; Duke, Mara A; Green, Damon; Hillbrand, Paul; Wilson Grimes, Kristin R; Nemeth, Richard S; Smith, Tyler B; Brandt, Marilyn
2017-01-01
Caribbean seagrass habitats provide food and protection for reef-associated juvenile fish. The invasive seagrass Halophila stipulacea is rapidly altering these seascapes. Since its arrival in the Caribbean in 2002, H. stipulacea has colonized and displaced native seagrasses, but the function of this invasive seagrass as a juvenile fish habitat remains unknown. To compare diversity, community structure, and abundance of juvenile fish between H. stipulacea and native seagrass beds, fish traps were deployed in four nearshore bays around St. Thomas, U.S. Virgin Islands. Traps were deployed in Frenchman, Lindbergh, and Sprat Bays for 24 h intervals in patches of bare sand, patches of H. stipulacea and patches of the native Caribbean seagrasses Thalassia testudinum and Syringodium filiforme. Traps were then deployed in Brewers Bay for 12 h intervals in stands of H. stipulacea and S. filiforme. Relative and total abundances of juvenile fish, identified at least to family, were compared across treatment habitats for each trap deployment period. The catch from H. stipulacea, compared to native seagrasses, comprised a greater abundance of nocturnal carnivores Lutjanus synagris (family Lutjanidae) and Haemulon flavolineatum (family Haemulidae). Additionally, the herbivore species Sparisoma aurofrenatum (family Labridae) and Acanthurus bahianus (family Acanthuridae) and the diurnal carnivore species Pseudopeneus maculatus (family Mullidae) were relatively scarce in H. stipulacea. The catch from sand was much smaller, compared to vegetated habitats, and comprised only L. synagris, H. flavolineatum, and H. aurolineatum. These results provide evidence of reduced family diversity and altered juvenile fish assemblages in H. stipulacea, driven by an abundance of some nocturnal carnivores and scarcity of herbivores and diurnal carnivores. The findings from the present work underpin the need for further investigation and mitigation of this invasion, particularly where H. stipulacea is driving seascape-alterations of key juvenile fish habitats.
Diamond, Jerome M; Bressler, David W; Serveiss, Victor B
2002-06-01
The free-flowing Clinch and Powell watershed in Virginia, USA, harbors a high number of endemic mussel and fish species but they are declining or going extinct at an alarming rate. To prioritize resource management strategies with respect to these fauna, a geographical information system was developed and various statistical approaches were used to relate human land uses with available fish, macroinvertebrate, and native mussel assemblage data. Both the Ephemeroptera, Plecoptera, Trichoptera (EPT) family-level index, and the fish index of biotic integrity (IBI) were lowest in a subwatershed with the greatest coal mining activity (analysis of variance [ANOVA], p < 0.05). Limited analyses in two other subwatersheds suggested that urban and agricultural land uses within a specified riparian corridor were more related to mussel species richness and fish IBI than land uses in entire catchments. Based on land uses within a riparian corridor of 200 m x 2 km for each biological site in the watershed, fish IBI was inversely related to percent cropland and urban area and positively related to pasture area (stepwise multiple regression, R2 = 0.55, p < 0.05). Sites less than 2 km downstream of urban areas, major highways, or coal mine activities had a significantly lower mean IBI value than those more than 2 km away (ANOVA, p < .05). Land use effects included poorer instream cover and higher substrate embeddedness (t test, p < 0.05). Weaker land use relationships were observed for EPT and mussel species richness. Episodic spills of toxic materials, originating from transportation corridors, mines, and industrial facilities, also have resulted in local extirpations of native species. particularly mussels. The number of co-occurring human activities was directly related to stream elevation in the Clinch River, with more human land uses in headwater areas. Approximately 60% of known U.S. Fish and Wildlife mussel concentration sites in the watershed are located within 2 km of at least two land use sources identified as potentially stressful in our analyses. Our results indicate that a number of land uses and stressors are probably responsible for the decline in native species. However, protection of naturally vegetated riparian corridors may help mitigate some of these effects.
Chase, Daniel A; Flynn, Erin E; Todgham, Anne E
2016-01-01
Abstract Reintroduction of endangered fishes to historic habitat has been used as a recovery tool; however, these fish may face competition from other fishes that established in their native habitat since extirpation. This study investigated the physiological response of tidewater goby, Eucyclogobius newberryi, an endangered California fish, when competing for food with threespine stickleback, Gasterosteus aculeatus, a native species, and rainwater killifish, Lucania parva, a non-native species. Survival, growth and physiological indicators of stress (i.e. cortisol, glucose and lactate concentrations) were assessed for juvenile fish held for 28 days in two food-limited conditions. When fed a 75% ration, survival of E. newberryi was significantly lower when held with G. aculeatus. In all fish assemblages, weight and relative condition decreased then stabilized over the 28 day experiment, while length remained unchanged. Whole-body cortisol in E. newberryi was not affected by fish assemblage; however, glucose and lactate concentrations were significantly higher with conspecifics than with other fish assemblages. When fed a 50% ration, survival of E. newberryi decreased during the second half of the experiment, while weight and relative condition decreased and length remained unchanged in all three fish assemblages. Cortisol concentrations were significantly higher for all fish assemblages compared with concentrations at the start of the experiment, whereas glucose and lactate concentrations were depressed relative to concentrations at the start of the experiment, with the magnitude of decrease dependent on the species assemblage. Our findings indicate that E. newberryi exhibited reduced growth and an elevated generalized stress response during low food availability. In response to reduced food availability, competition with G. aculeatus had the greatest physiological effect on E. newberryi, with minimal effects from the non-native L. parva. This study presents the first reported cortisol, glucose and lactate concentrations in response to chronic stress for E. newberryi. PMID:27293761
Harper, David; Farag, Aida
2017-01-01
We evaluated the thermal regime and relative abundance of native and nonnative fish and invertebrates within Kelly Warm Spring and Savage Ditch, Grand Teton National Park, Wyoming. Water temperatures within the system remained relatively warm year-round with mean temperatures >20 °C near the spring source and >5 °C approximately 2 km downstream of the source. A total of 7 nonnative species were collected: Convict/Zebra Cichlid (Cichlasoma nigrofasciatum), Green Swordtail (Xiphophorus hellerii), Tadpole Madtom (Noturus gyrinus), Guppy (Poecilia reticulata), Goldfish (Carassius auratus), red-rimmed melania snail (Melanoides tuberculata), and American bullfrog tadpoles (Lithobates catesbeianus). Nonnative fish (Zebra Cichlids and Green Swordtails), red-rimmed melania snails, and bullfrog tadpoles dominated the upper 2 km of the system. Abundance estimates of the Zebra Cichlid exceeded 12,000 fish/km immediately downstream of the spring source. Relative abundance of native species increased movingdownstream as water temperatures attenuated with distance from the thermally warmed spring source; however, nonnative species were captured 4 km downstream from the spring. Fish diseases were prevalent in both native and nonnative fish from the Kelly Warm Spring pond. Clinostomum marginatum, a trematode parasite, was found in native species samples, and the tapeworm Diphyllobothrium dendriticum was present in samples from nonnative species. Diphyllobothrium dendriticum is rare in Wyoming. Salmonella spp. were also found in some samples of nonnative species. These bacteria are associated with aquarium fish and aquaculture and are generally not found in the wild.
Valdivia, Abel; Cox, Courtney E.; Silbiger, Nyssa J.; Bruno, John F.
2017-01-01
Invasive lionfish are assumed to significantly affect Caribbean reef fish communities. However, evidence of lionfish effects on native reef fishes is based on uncontrolled observational studies or small-scale, unrepresentative experiments, with findings ranging from no effect to large effects on prey density and richness. Moreover, whether lionfish affect populations and communities of native reef fishes at larger, management-relevant scales is unknown. The purpose of this study was to assess the effects of lionfish on coral reef prey fish communities in a natural complex reef system. We quantified lionfish and the density, richness, and composition of native prey fishes (0–10 cm total length) at sixteen reefs along ∼250 km of the Belize Barrier Reef from 2009 to 2013. Lionfish invaded our study sites during this four-year longitudinal study, thus our sampling included fish community structure before and after our sites were invaded, i.e., we employed a modified BACI design. We found no evidence that lionfish measurably affected the density, richness, or composition of prey fishes. It is possible that higher lionfish densities are necessary to detect an effect of lionfish on prey populations at this relatively large spatial scale. Alternatively, negative effects of lionfish on prey could be small, essentially undetectable, and ecologically insignificant at our study sites. Other factors that influence the dynamics of reef fish populations including reef complexity, resource availability, recruitment, predation, and fishing could swamp any effects of lionfish on prey populations. PMID:28560093
Hackerott, Serena; Valdivia, Abel; Cox, Courtney E; Silbiger, Nyssa J; Bruno, John F
2017-01-01
Invasive lionfish are assumed to significantly affect Caribbean reef fish communities. However, evidence of lionfish effects on native reef fishes is based on uncontrolled observational studies or small-scale, unrepresentative experiments, with findings ranging from no effect to large effects on prey density and richness. Moreover, whether lionfish affect populations and communities of native reef fishes at larger, management-relevant scales is unknown. The purpose of this study was to assess the effects of lionfish on coral reef prey fish communities in a natural complex reef system. We quantified lionfish and the density, richness, and composition of native prey fishes (0-10 cm total length) at sixteen reefs along ∼250 km of the Belize Barrier Reef from 2009 to 2013. Lionfish invaded our study sites during this four-year longitudinal study, thus our sampling included fish community structure before and after our sites were invaded, i.e., we employed a modified BACI design. We found no evidence that lionfish measurably affected the density, richness, or composition of prey fishes. It is possible that higher lionfish densities are necessary to detect an effect of lionfish on prey populations at this relatively large spatial scale. Alternatively, negative effects of lionfish on prey could be small, essentially undetectable, and ecologically insignificant at our study sites. Other factors that influence the dynamics of reef fish populations including reef complexity, resource availability, recruitment, predation, and fishing could swamp any effects of lionfish on prey populations.
Susan B. Adams
2006-01-01
For The incised, sand-bed streams of northcentral Mississippi, USA, fish predation is one plausible mechanism to explain both relatively low crayfish densities and differences in stream size occupied by various native crayfishes. I conducted two mesocosm experiments to test effects of a fish predator (channel catfish, Ictalurus punctahls) on the...
Species richness and patterns of invasion in plants, birds, and fishes in the United States
Thomas J. Stohlgren; David T. Barnett; Curtis H. Flather; Pam L. Fuller; Bruce G. Peterjohn; John T. Kartesz; Lawrence L. Master
2006-01-01
We quantified broad-scale patterns of species richness and species density (mean # species/km2) for native and non-indigenous plants, birds, and fishes in the continental USA and Hawaii. We hypothesized that the species density of native and non-indigenous taxa would generally decrease in northern latitudes and higher elevations following...
NASA Astrophysics Data System (ADS)
Techarang, Jiranat; Apichartsrangkoon, Arunee; Phanchaisri, Boonrak; Pathomrungsiyoungkul, Pattavara; Sriwattana, Sujinda
2017-07-01
Swai-fish emulsions containing fermented soybeans (thua nao and rice-koji miso) were pressurized at 600 MPa for 20 min or heated at 72°C for 30 min. The fish batters were blended with soy protein isolate (SPI) or whey protein concentrate (WPC) to stabilize the emulsions. The processed fish emulsions were then subjected to physical, chemical and microbiological examinations. The results of gel strength and water-holding potential showed that SPI addition yielded higher impact on these properties than WPC addition, which was also confirmed by the interactions between SPI and native fish proteins depicted by electrophoregrams. The frequency profiles suggested that the heated gels had a greater storage and loss moduli than pressurized gels, while pressurized WPC set-gel displayed larger loss tangent (the predominance of viscous moiety) than those pressurized SPI set-gel. High bacteria and spore counts of B. subtilis (residual of the thua nao) were observed in both pressurized and heated fish-based emulsions.
Pérez-Ponce de León, G; Lagunas-Calvo, O; García-Prieto, L; Briosio-Aguilar, R; Aguilar-Aguilar, R
2018-05-01
The Asian fish tapeworm, Schyzocotyle acheilognathi (syn. Bothriocephalus acheilognathi) represents a threat to freshwater fish, mainly cyprinids, across the globe. This tapeworm possesses an extraordinary ability to adapt to different environmental conditions and, because of that, from its natural geographical origin in mainland Asia, it has colonized every continent except Antarctica. It is thought that this pathogenic tapeworm was first co-introduced into Mexico in 1965 from China, with the grass carp Ctenopharyngodon idella, although the first formal record of its presence was published in 1981. Over the past 35 years, the Asian fish tapeworm has invaded about 22% of the freshwater fish in Mexico. Because fish communities in Mexico are characterized by high species richness and levels of endemism, S. acheilognathi is considered as a co-introduced and co-invasive species. In this review, we update the geographic distribution and host spectrum of the Asian fish tapeworm in Mexico. Up until December 2016, the tapeworm had been recorded in 110 freshwater fish species (96 native and 14 introduced), included in 51 genera, 11 families and 4 orders; it was also widely distributed in all types of aquatic environments, and has been found in 214 localities. We present novel data from a survey aimed at establishing the distribution pattern of the tapeworm in native freshwater fishes of two rivers in north-central Mexico, and the genetic variation among individuals of this co-invasive species collected from different host species and localities. We discuss briefly the factors that have determined the remarkable invasive success of this parasite in freshwater systems in Mexico.
Gagne, Roderick B; Heins, David C; McIntyre, Peter B; Gilliam, James F; Blum, Michael J
2016-10-01
The presence of introduced hosts can increase or decrease infections of co-introduced parasites in native species of conservation concern. In this study, we compared parasite abundance, intensity, and prevalence between native Awaous stamineus and introduced poeciliid fishes by a co-introduced nematode parasite (Camallanus cotti) in 42 watersheds across the Hawaiian Islands. We found that parasite abundance, intensity and prevalence were greater in native than introduced hosts. Parasite abundance, intensity and prevalence within A. stamineus varied between years, which largely reflected a transient spike in infection in three remote watersheds on Molokai. At each site we measured host factors (length, density of native host, density of introduced host) and environmental factors (per cent agricultural and urban land use, water chemistry, watershed area and precipitation) hypothesized to influence C. cotti abundance, intensity and prevalence. Factors associated with parasitism differed between native and introduced hosts. Notably, parasitism of native hosts was higher in streams with lower water quality, whereas parasitism of introduced hosts was lower in streams with lower water quality. We also found that parasite burdens were lower in both native and introduced hosts when coincident. Evidence of a mutual dilution effect indicates that introduced hosts can ameliorate parasitism of native fishes by co-introduced parasites, which raises questions about the value of remediation actions, such as the removal of introduced hosts, in stemming the rise of infectious disease in species of conservation concern.
Meador, Michael R.; Carlisle, Daren M.
2009-01-01
Management and conservation of aquatic systems require the ability to assess biological conditions and identify changes in biodiversity. Predictive models for fish assemblages were constructed to assess biological condition and changes in biodiversity for streams sampled in the eastern United States as part of the U.S. Geological Survey's National Water Quality Assessment Program. Separate predictive models were developed for northern and southern regions. Reference sites were designated using land cover and local professional judgment. Taxonomic completeness was quantified based on the ratio of the number of observed native fish species expected to occur to the number of expected native fish species. Models for both regions accurately predicted fish species composition at reference sites with relatively high precision and low bias. In general, species that occurred less frequently than expected (decreasers) tended to prefer riffle areas and larger substrates, such as gravel and cobble, whereas increaser species (occurring more frequently than expected) tended to prefer pools, backwater areas, and vegetated and sand substrates. In the north, the percentage of species identified as increasers and the percentage identified as decreasers were equal, whereas in the south nearly two-thirds of the species examined were identified as decreasers. Predictive models of fish species can provide a standardized indicator for consistent assessments of biological condition at varying spatial scales and critical information for an improved understanding of fish species that are potentially at risk of loss with changing water quality conditions.
Status of native fishes in the western United States and issues for fire and fuels management
Rieman, B.; Lee, D.; Burns, D.; Gresswell, Robert E.; Young, M.; Stowell, R.; Rinne, J.; Howell, P.
2003-01-01
Conservation of native fishes and changing patterns in wildfire and fuels are defining challenges for managers of forested landscapes in the western United States. Many species and populations of native fishes have declined in recorded history and some now occur as isolated remnants of what once were larger more complex systems. Land management activities have been viewed as one cause of this problem. Fires also can have substantial effects on streams and riparian systems and may threaten the persistence of some populations of fish, particularly those that are small and isolated. Despite that, major new efforts to actively manage fires and fuels in forests throughout the region may be perceived as a threat rather than a benefit to conservation of native fishes and their habitats. The management of terrestrial and aquatic resources has often been contentious, divided among a variety of agencies with different goals and mandates. Management of forests, for example, has generally been viewed as an impact on aquatic systems. Implementation of the management-regulatory process has reinforced a uniform approach to mitigate the threats to aquatic species and habitats that may be influenced by management activities. The problems and opportunities, however, are not the same across the landscapes of interest. Attempts to streamline the regulatory process often search for generalized solutions that may oversimplify the complexity of natural systems. Significant questions regarding the influence of fire on aquatic ecosystems, changing fire regimes, and the effects of fire-related management remain unresolved and contribute to the uncertainty. We argue that management of forests and fishes can be viewed as part of the same problem, that of conservation and restoration of the natural processes that create diverse and productive ecosystems. We suggest that progress toward more integrated management of forests and native fishes will require at least three steps: (1) better integration and development of a common conceptual foundation and ecological goals; (2) attention to landscape and ecological context; and (3) recognition of uncertainty.
Wesley, Neal J.; Lilyestrom, Craig G.; Kwak, T.J.
2009-01-01
Anthropogenic effects including river regulation, watershed development, contamination, and fish introductions have substantially affected the majority of freshwater habitats in Europe and North America. This pattern of resource development and degradation is widespread in the tropics, and often little is known about the resources before they are lost. This article describes the freshwater resources of Puerto Rico and identifies factors that threaten conservation of native fishes. The fishes found in freshwater habitats of Puerto Rico represent a moderately diverse assemblage composed of 14 orders, 29 families, and 82 species. There are fewer than 10 species of native peripherally-freshwater fish that require a link to marine systems. Introductions of nonindigenous species have greatly expanded fish diversity in freshwater systems, and native estuarine and marine species (18 families) also commonly enter lowland rivers and brackish lagoons. Environmental alterations, including land use and development, stream channelization, pollution, and the impoundment of rivers, combined with nonnative species introductions threaten the health and sustainability of aquatic resources in Puerto Rico. Six principal areas for attention that are important influences on the current and future status of the freshwater fish resources of Puerto Rico are identified and discussed.
Lake Ontario benthic prey fish assessment, 2014
Weidel, Brian C.; Walsh, Maureen
2015-01-01
Benthic prey fishes are an important component of the Lake Ontario fish community and serve as vectors that move energy from benthic invertebrates into native and introduced sport fishes. Since the 1970’s, the USGS Lake Ontario Biological Station has assessed benthic fish populations and community dynamics with bottom trawls at depths ranging from 8 m out to depths of 150-225 m along the south and eastern shores of Lake Ontario. From the late 1970’s through the early 2000’s the benthic fish community was dominated by Slimy Sculpin Cottus cognatus, but in 2004 non-native Round Goby Neogobius melanostomus abundance increased and, since then Round Goby have generally been the dominant benthic species. Over the past 10 years the native Deepwater Sculpin Myoxocephalus thompsonii, once considered absent from the lake, have increased. Presently their lake-wide biomass density is equal to, or larger than, Slimy Sculpin. Species-specific assessments found Slimy and Deepwater Sculpin abundance increased slightly in 2014 relative to 2013, while changes in Round Goby abundance differed between spring and fall survey. Recent survey modifications have increased our understanding of benthic prey fish abundance and behavior in Lake Ontario. For instance, increasing the maximum tow depth to 225 m in 2014 improved our understanding of Deepwater Sculpin distribution in this rarely sampled lake habitat.
Native fishes of arid lands: A dwindling resource of the desert southwest
John N. Rinne; W. L. Minckley
1991-01-01
Includes color photos of 44 species of fishes, many published for the first time. Text describes aquatic systems in the mountains and deserts of the Southwest, the unique fishes they support, and habitats the fishes need.
Thomson, S.K.; Berry, C.R.; Niehus, C.A.; Wall, S.S.; ,
2005-01-01
Livestock watering holes (i.e., dugouts) are typically constructed in floodplains, yet the influence of dugouts on native prairie fishes is unknown. Such information is necessary for the effective management of native fishes, especially species of concern such as the endangered Topeka shiner (Notropis topeka). The goal of our study was to suggest technical guidelines for constructing floodplain wetlands that are compatible with stream fish resources. Specific objectives were to: determine the flood frequencies of the connection between streams and dugouts; determine fish community characteristics in floodplain dugouts; and, associate dugout characteristics with fish assemblages. A total of 20 dugouts within Six Mile Creek watershed, South Dakota, were surveyed seasonally (excluding winter) from fall of 2003 to fall of 2004. Dugouts were categorized according to their lateral floodplain placement (connectivity with the stream and flood frequency of the stream-dugout connection) and longitudinal placement across the watershed. Fishes were sampled in dugouts and adjacent stream reaches with seines and traps. The 21 species making up the stream and dugout fish assemblages were similar. Fish inhabited 65% of the dugouts; 30% contained Topeka shiners. Most fish inhabitance, and all Topeka shiner occurrences, were in dugouts that were headwater sites and were either directly connected to the stream or disconnected and frequently flooded (average 1 in 2 year event). Two dugouts in this latter category contained the most abundant, self-sustaining Topeka shiner populations. Constructing dugouts separate from the stream within frequently inundated zones can provide off-channel habitat for fishes.
25 CFR 241.5 - Commercial fishing, Karluk Indian Reservation.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 25 Indians 1 2014-04-01 2014-04-01 false Commercial fishing, Karluk Indian Reservation. 241.5... FISHING IN ALASKA § 241.5 Commercial fishing, Karluk Indian Reservation. (a) Definition. The Karluk Indian... Karluk Indian Reservation shall be open to commercial fishing by bona fide native inhabitants of the...
Angermeier, Paul L.; Frimpong, Emmanuel A.
2009-01-01
The need for integrated and widely accessible sources of species traits data to facilitate studies of ecology, conservation, and management has motivated development of traits databases for various taxa. In spite of the increasing number of traits-based analyses of freshwater fishes in the United States, no consolidated database of traits of this group exists publicly, and much useful information on these species is documented only in obscure sources. The largely inaccessible and unconsolidated traits information makes large-scale analysis involving many fishes and/or traits particularly challenging. FishTraits is a database of >100 traits for 809 (731 native and 78 exotic) fish species found in freshwaters of the conterminous United States, including 37 native families and 145 native genera. The database contains information on four major categories of traits: (1) trophic ecology, (2) body size and reproductive ecology (life history), (3) habitat associations, and (4) salinity and temperature tolerances. Information on geographic distribution and conservation status is also included. Together, we refer to the traits, distribution, and conservation status information as attributes. Descriptions of attributes are available here. Many sources were consulted to compile attributes, including state and regional species accounts and other databases.
Aquatic species invasions in the context of fire and climate change
Michael K. Young
2012-01-01
This paper focuses on the nexus among native and nonnative fishes with respect to fire and climate change in the western United States. Although many taxa are involved, I emphasize native and nonnative salmonids because these are obligate coldwater species that might be expected to respond strongly to fire and because most research has been conducted on these fishes....
R.A. Knapp; K.R. Matthews
2000-01-01
Abstract: One of the most puzzling aspects of the worldwide decline of amphibians is their disappearance from within protected areas. Because these areas are ostensibly undisturbed, habitat alterations are generally perceived as unlikely causes. The introduction of non-native fishes into protected areas, however, is a common practice throughout the world and may exert...
Effects of proposed alternatives on aquatic habitats and native fishes [Chapter 3
James R. Sedell; Danny C. Lee; Bruce E. Rieman; Russell F. Thurow; Jack E. Williams
1997-01-01
The Aquatics and Riparian Science Teams analyzed the seven alternatives by evaluating their effectiveness in sustaining aquatic ecosystem structure and function, and their expected effect on 25 taxa of native fishes. Our analysis focused on alternatives as defined in Chapter 3 of the Preliminary Draft Environmental Impact Statements (EISs) (USDA and USDI 1996a, 1996b...
Korman, Josh; Martell, Steven J.D.; Walters, Carl J.; Makinster, Andrew S.; Coggins, Lewis G.; Yard, Michael D.; Persons, William R.
2012-01-01
We used an integrated assessment model to examine effects of flow from Glen Canyon Dam, Arizona, USA, on recruitment of nonnative rainbow trout (Oncorhynchus mykiss) in the Colorado River and to estimate downstream migration from Glen Canyon to Marble Canyon, a reach used by endangered native fish. Over a 20-year period, recruitment of rainbow trout in Glen Canyon increased with the annual flow volume and when hourly flow variation was reduced and after two of three controlled floods. The model predicted that approximately 16 000 trout·year–1 emigrated to Marble Canyon and that the majority of trout in this reach originate from Glen Canyon. For most models that were examined, over 70% of the variation in emigration rates was explained by variation in recruitment in Glen Canyon, suggesting that flow from the dam controls in large part the extent of potential negative interactions between rainbow trout and native fish. Controlled floods and steadier flows, which were originally aimed at partially restoring conditions before the dam (greater native fish abundance and larger sand bars), appear to have been more beneficial to nonnative rainbow trout than to native fish.
A Phylogenetic Perspective on the Evolution of Mediterranean Teleost Fishes
Meynard, Christine N.; Mouillot, David; Mouquet, Nicolas; Douzery, Emmanuel J. P.
2012-01-01
The Mediterranean Sea is a highly diverse, highly studied, and highly impacted biogeographic region, yet no phylogenetic reconstruction of fish diversity in this area has been published to date. Here, we infer the timing and geographic origins of Mediterranean teleost species diversity using nucleotide sequences collected from GenBank. We assembled a DNA supermatrix composed of four mitochondrial genes (12S ribosomal DNA, 16S ribosomal DNA, cytochrome c oxidase subunit I and cytochrome b) and two nuclear genes (rhodopsin and recombination activating gene I), including 62% of Mediterranean teleost species plus 9 outgroups. Maximum likelihood and Bayesian phylogenetic and dating analyses were calibrated using 20 fossil constraints. An additional 124 species were grafted onto the chronogram according to their taxonomic affinity, checking for the effects of taxonomic coverage in subsequent diversification analyses. We then interpreted the time-line of teleost diversification in light of Mediterranean historical biogeography, distinguishing non-endemic natives, endemics and exotic species. Results show that the major Mediterranean orders are of Cretaceous origin, specifically ∼100–80 Mya, and most Perciformes families originated 80–50 Mya. Two important clade origin events were detected. The first at 100–80 Mya, affected native and exotic species, and reflects a global diversification period at a time when the Mediterranean Sea did not yet exist. The second occurred during the last 50 Mya, and is noticeable among endemic and native species, but not among exotic species. This period corresponds to isolation of the Mediterranean from Indo-Pacific waters before the Messinian salinity crisis. The Mediterranean fish fauna illustrates well the assembly of regional faunas through origination and immigration, where dispersal and isolation have shaped the emergence of a biodiversity hotspot. PMID:22590545
NASA Astrophysics Data System (ADS)
Pajuelo, José G.; González, José A.; Triay-Portella, Raül; Martín, José A.; Ruiz-Díaz, Raquel; Lorenzo, José M.; Luque, Ángel
2016-11-01
This work documents the introduction of non-native fish species to the Canary Islands (central-eastern Atlantic) through oil rigs. Methodological approaches have included surveys by underwater visual censuses around and under oil platforms and along the docking area of rigs at the Port of Las Palmas. Eleven non-native fish species were registered. Paranthias furcifer, Abudefduf hoefleri, Acanthurus bahianus, Acanthurus chirurgus, and Acanthurus coeruleus are first recorded from the Canaries herein. Other three species could not be identified, although they have never been observed in the Canaries. Cephalopholis taeniops, Abudefduf saxatilis, and Acanthurus monroviae had been previously recorded. Native areas of these species coincide with the areas of origin and the scale of oil rigs with destination the Port of Las Palmas. The absence of native species in the censuses at rigs and their presence at rigs docking area, together with the observation of non-native species after the departure of platforms, reject the possibility that these non-native species were already present in the area introduced by another vector. C. taeniops, A. hoefleri, A. saxatilis, A. chirurgus, A. coeruleus and A. monroviae are clearly seafarer species. A. bahianus seems to be a potential seafarer species. P. furcifer is a castaway species. For the moment, the number of individuals of the non-native species in marine ecosystems of the Canaries seems to be low, and more investigation is needed for controlling these translocations.
Nico, Leo; Englund, Ronald A.; Jelks, Howard L.
2015-01-01
Mozambique tilapia Oreochromis mossambicus were recently discovered in ‘Aimakapā Fishpond, a 12-hectare brackish-water wetland complex in Kaloko-Honokōhau National Historical Park, on the Island of Hawai’i. As a possible eradication method, we evaluated rotenone, a natural piscicide used in fish management and the active ingredient in plants traditionally used by indigenous Hawaiians for capturing fish. To assess rotenone’s efficacy in killing tilapia and effects on non-target species, laboratory toxicity tests involved exposing organisms to various concentrations of liquid CFT Legumine (5% rotenone) in static trials of 48-h to 72-h duration. Test organisms included: Mozambique tilapia, non-native guppy Poecilia reticulata, the non-native odonate Rambur’s forktail Ischnura ramburii, native feeble shrimp Palaemon debilis, and native ‘ōpae’ula shrimp Halocaridina rubra. All organisms and water used in tests were obtained from ‘Aimakapā (12.6–12.7 ppt salinity), or, for H. rubra, an anchialine pool (15.0–15.2 ppt salinity). Survival analyses indicated CFT Legumine concentrations >3 ppm (>0.15 mg/L rotenone) achieved 100% mortality of tilapia and 93% of guppies within 24 h, with most tilapia killed by 6 h and most guppies by 2 h. Little or no mortality was observed among invertebrate exposed to 1 to 5 mg/L CFT Legumine: 0% mortality for ‘ōpae’ula shrimp, 4% for feeble shrimp; and 16% for odonate larvae. The 48 h LC50 values for Mozambique tilapia and guppy were 0.06 and 0.11 mg/L rotenone, respectively. Results demonstrate rotenone’s potential for non-native fish eradication in brackish-water habitats, with benefit of low mortality to certain macro-invertebrates. High rotenone tolerance displayed by ‘ōpae’ula shrimp is noteworthy. Invasive fish are common in anchialine pools, threatening existence of shrimp and other invertebrate fauna. Although rotenone’s effects on freshwater organisms have been well studied, our research represents one of only a few controlled laboratory experiments quantitatively assessing rotenone tolerance of brackish or marine fauna.
Sellers, Andrew J; Ruiz, Gregory M; Leung, Brian; Torchin, Mark E
2015-01-01
Parasites can play an important role in biological invasions. While introduced species often lose parasites from their native range, they can also accumulate novel parasites in their new range. The accumulation of parasites by introduced species likely varies spatially, and more parasites may shift to new hosts where parasite diversity is high. Considering that parasitism and disease are generally more prevalent at lower latitudes, the accumulation of parasites by introduced hosts may be greater in tropical regions. The Indo-Pacific lionfish (Pterois volitans) has become widely distributed across the Western Atlantic. In this study, we compared parasitism across thirteen locations in four regions, spanning seventeen degrees of latitude in the lionfish's introduced range to examine potential spatial variation in parasitism. In addition, as an initial step to explore how indirect effects of parasitism might influence interactions between lionfish and ecologically similar native hosts, we also compared parasitism in lionfish and two co-occurring native fish species, the graysby grouper, Cephalopholis cruentata, and the lizardfish, Synodus intermedius, in the southernmost region, Panama. Our results show that accumulation of native parasites on lionfish varies across broad spatial scales, and that colonization by ectoparasites was highest in Panama, relative to the other study sites. Endoparasite richness and abundance, on the other hand, were highest in Belize where lionfish were infected by twice as many endoparasite species as lionfish in other regions. The prevalence of all but two parasite species infecting lionfish was below 25%, and we did not detect an association between parasite abundance and host condition, suggesting a limited direct effect of parasites on lionfish, even where parasitism was highest. Further, parasite species richness and abundance were significantly higher in both native fishes compared to lionfish, and parasite abundance was negatively associated with the condition index of the native grouper but not that of the lionfish or lizardfish. While two co-occurring native fishes were more heavily parasitized compared to lionfish in Panama any indirect benefits of differential parasitism requires further investigation. Future parasitological surveys of lionfish across the eastern coast of North America and the Lesser Antilles would further resolve geographic patterns of parasitism in invasive lionfish.
MICROSATELLITE CHARACTERIZATION IN CENTRAL STONEROLLER CAMPOSTOMA ANOMALUM (PISCES: CYPRINIDAE)
The central stoneroller (Campostoma anomalum) is a small cyprinid fish that is native to streams and rivers of central and eastern North America. It can be found in a range of anthropo- genically modified habitats, ranging from nearly pristine to highly polluted waters (Zimmerma...
Nugegoda, Dayanthi; Kibria, Golam
2017-04-01
Numerous environmental stressors exert acute or chronic effects on the fish thyroid cascade. Such effects could be mediated via thyroidal alterations, imbalance of plasma T4 and T3 levels or damage to the structure of the thyroidal tissues (thyroid hypertrophy, hyperplasia). The thyroidal system is intricately linked to other endocrine systems in vertebrates including the control of reproduction. Disruption of fish thyroid function by environmental stressors has the potential to result in deleterious effects including the inhibition of sperm production, reduction in egg production, gonad development, ovarian growth, swimming activity, fertilisation and increase in larval mortality. Thyroid hormones play a major role in the development and growth of fish, particularly during their early life stages, thus, thyroid disruption by environmental stressors could inhibit the growth of fish larvae and juveniles in wild fish and cultured species, limit fish seed production and result in a decline in wild fisheries. This review highlights the effects of several environmental toxicants including PBDE, PCBs, PCDD and PCDF, PAH/oil, phthalates, metals, pesticides, mixed pollutants/chemicals, cyanide; and other stressors including acid (low pH) and ammonia, on fish thyroid function. Environmental sources of chemical stressors and appropriate water quality guidelines to protect the freshwater and marine species for the relevant pollutants are also discussed including (when available) the Australian guidelines (2000) and Canadian water quality guidelines (where Australian guidelines are not available). To date there has been no published research on the effects of anthropogenic environmental pollutants on the thyroid system of any native Australian fish species. However, the detection of high risk chemicals (notably PBDEs, PCBs, PAHs, metals and pesticides) in Australian waterways and Australian fish and shellfish implies that thyroid disruption of Australian wild fish and aquacultured species could occur. It is therefore imperative that the effects of such pollutants on the thyroid system of Australian native fish be investigated. Copyright © 2016 Elsevier Inc. All rights reserved.
Scoppettone, G.G.; Salgado, J.A.; Nielsen, M.B.
2005-01-01
Blue tilapia (Oreochromis aureus), native to North Africa and the Middle East (Courtenay and Robins 1973, Fuller et al. 1999), has been introduced around the world as a human food source, for vegetation control, and as a game fish (Costa-Pierce and Riedel 2000). Blue tilapia has been particularly successful in establishing and spreading in North American waters where it has been reported to change fish community structure and cause native fish decline (Courtenay and Robins 1973, Fuller et al. 1999). Because of these detrimental effects, it is now generally considered an unwelcome introduction into North American waters (Dill and Cordone 1997, Fuller et al. 1999).
Ross, Robert P.; Vernieu, William S.
2013-01-01
Since the completion of Glen Canyon Dam, Arizona, in 1963, downstream water temperatures in the main channel of the Colorado River in Glen, Marble, and Grand Canyons are much colder in summer. This has negatively affected humpback chub (Gila cypha) and other native fish adapted to seasonally warm water, reducing main-channel spawning activity and impeding the growth and development of larval and juvenile fish. Recently published studies by U.S. Geological Survey scientists found that under certain conditions some isolated nearshore environments in Grand Canyon allow water to become separated from the main-channel current and to warm, providing refuge areas for the development of larval and juvenile fish.
Chasqui-Velasco, Luis; Alvarado Ch, Elvira; Acero, Arturo; Zapata, Fernando A
2007-01-01
To examine the effects of herbivorous and corallivorous fishes on the survival of transplanted colonies of Montastraea annularis, Diploria labyrinthiformis and Porites astreoides, both transplanted and native colonies were full-cage enclosed and compared to open (uncaged) colonies, while caging effects were assessed with a partial-cage (roof treatment). To evaluate if transplant stress increased the corals availability to fish predation, comparisons of fish foraging intensity among transplanted versus native colonies were made. To determine the density of herbivorous and corallivorous fishes on the transplants area visual censuses were made. The transient herbivorous fishes (Scaridae and Acanthuridae) were the most abundant fishes, and the corallivorous fishes (mainly Chaetodontidae) were the scarcest. A negative effect of territorial herbivorous fishes on M annularis transplants survival was observed, mainly early on the study. Fish foraging intensity was similar on transplanted and native colonies, but differed among coral species, being lowest on D. labyrinthiformis. Fast macroalgal growth inside full-cages due to reduced fish grazing was observed. This caused partial bleaching and partial mortality in some colonies, mainly of P. astreoides. No significant difference in healthy tissue percentages among full-cage and uncaged colonies on M. annularis and D. labyrinthiformis was found, while in P. astreoides there were evilent differences. The results indicate a damselfish negative effect on transplants survival early on the study, which can change depending on the fish and coral species involved. Results also indicate a fish grazing positive effect, caused by the reduction of coral-algae competition pressure, mainly on P. astreoides. Parrotfishes seem to affect corals survival both negatively through direct biting, and positively by controlling algal growth. Overall, coral transplant success was almost unaffected by fish foraging activity although several differences among coral species were obvious in relation to colony shape. Additionally, the interaction among herbivorous fish grazing and coral-algae competition balance appear important in determining transplant survival.
Current status of non-native fish species in the St. Louis River estuary
The fish community of the St. Louis River estuary is well characterized, thanks to fishery assessment and invasive species early detection monitoring by federal, state, and tribal agencies. This sampling includes long-standing adult/juvenile fish surveys, larval fish surveys beg...
A description of the nearshore fish communities in the Huron-Erie Corridor using multiple gear types
Francis, James T.; Chiotti, Justin A.; Boase, James C.; Thomas, Mike V.; Manny, Bruce A.; Roseman, Edward F.
2013-01-01
Great Lakes coastal wetlands provide a critical habitat for many fish species throughout their life cycles. Once home to one of the largest wetland complexes in the Great Lakes, coastal wetlands in the Huron–Erie Corridor (HEC) have decreased dramatically since the early 1900s. We characterized the nearshore fish communities at three different wetland complexes in the HEC using electrofishing, seines, and fyke nets. Species richness was highest in the Detroit River (63), followed by the St. Clair Delta (56), and Western Lake Erie (47). The nearshore fish communities in the Detroit River and St. Clair Delta consisted primarily of shiners, bluntnose minnow, centrarchids, and brook silverside, while the Western Lake Erie sites consisted of high proportions of non-native taxa including common carp, gizzard shad, goldfish, and white perch. Species richness estimates using individual-based rarefaction curves were higher when using electrofishing data compared to fyke nets or seine hauls at each wetland. Twelve fish species were captured exclusively during electrofishing assessments, while one species was captured exclusively in fyke nets, and none exclusively during seine hauls. Western Lake Erie wetlands were more indicative of degraded systems with lower species richness, lower proportion of turbidity intolerant species, and increased abundance of non-native taxa. This work highlights the importance of coastal wetlands in the HEC by capturing 69 different fish species utilizing these wetlands to fulfill life history requirements and provides insight when selecting gears to sample nearshore littoral areas.
Tavakol, Sareh; Halajian, Ali; Smit, Willem J; Hoffman, Andre; Luus-Powell, Wilmien J
2017-12-01
Introduced alien fish species and their associated parasites may result in a serious threat to indigenous biodiversity. Furthermore, this may have negative impacts on cultured fish as well as on native parasitic fauna. In the present study, the invasive Asian nematode, Camallanus cotti Fujita, 1927 (Nematoda: Camallanidae), is reported from the guppy (Poecilia reticulata) for the first time in Africa. This parasite is assumed to be introduced into Africa along with the introduction of exotic poeciliid fishes, which are known to be the most common hosts of C. cotti in ornamental fish industry worldwide.The presence of this parasite in both aquarium-cultured fish as well as fish from natural waterbodies is evidence of the introduction of the alien organisms due to insufficient prophylactic veterinary control during transfer of non-native hosts between countries and the spread of them by the anthropogenic introduction to natural systems.
Schloesser, J.T.; Paukert, Craig P.; Doyle, W.J.; Hill, T.; Steffensen, K.D.; Travnichek, Vincent H.
2012-01-01
Large rivers throughout the world have been modified by using dike structures to divert water flows to deepwater habitats to maintain navigation channels. These modifications have been implicated in the decline in habitat diversity and native fishes. However, dike structures have been modified in the Missouri River USA to increase habitat diversity to aid in the recovery of native fishes. We compared species occupancy and fish community composition at natural sandbars and at notched and un-notched rock dikes along the lower Missouri River to determine if notching dikes increases species diversity or occupancy of native fishes. Fish were collected using gill nets, trammel nets, otter trawls, and mini fyke nets throughout the lower 1212 river km of the Missouri River USA from 2003 to 2006. Few differences in species richness and diversity were evident among engineered dike structures and natural sandbars. Notching a dike structure had no effect on proportional abundance of fluvial dependents, fluvial specialists, and macrohabitat generalists. Occupancy at notched dikes increased for two species but did not differ for 17 other species (81%). Our results suggest that dike structures may provide suitable habitats for fluvial species compared with channel sand bars, but dike notching did not increase abundance or occupancy of most Missouri River fishes. Published in 2011 by John Wiley & Sons, Ltd.
Floodplain farm fields provide novel rearing habitat for Chinook salmon
Jeffres, Carson; Conrad, J. Louise; Sommer, Ted R.; Martinez, Joshua; Brumbaugh, Steve; Corline, Nicholas; Moyle, Peter B.
2017-01-01
When inundated by floodwaters, river floodplains provide critical habitat for many species of fish and wildlife, but many river valleys have been extensively leveed and floodplain wetlands drained for flood control and agriculture. In the Central Valley of California, USA, where less than 5% of floodplain wetland habitats remain, a critical conservation question is how can farmland occupying the historical floodplains be better managed to improve benefits for native fish and wildlife. In this study fields on the Sacramento River floodplain were intentionally flooded after the autumn rice harvest to determine if they could provide shallow-water rearing habitat for Sacramento River fall-run Chinook salmon (Oncorhynchus tshawytscha). Approximately 10,000 juvenile fish (ca. 48 mm, 1.1 g) were reared on two hectares for six weeks (Feb-March) between the fall harvest and spring planting. A subsample of the fish were uniquely tagged to allow tracking of individual growth rates (average 0.76 mm/day) which were among the highest recorded in fresh water in California. Zooplankton sampled from the water column of the fields were compared to fish stomach contents. The primary prey was zooplankton in the order Cladocera, commonly called water fleas. The compatibility, on the same farm fields, of summer crop production and native fish habitat during winter demonstrates that land management combining agriculture with conservation ecology may benefit recovery of native fish species, such as endangered Chinook salmon. PMID:28591141
Gutierrel, Silvia M M; Schofield, Pam; Prodocimo, Viviane
2016-01-01
Astronotus ocellatus (oscar), is native to the Amazon basin and, although it has been introduced to many countries, little is known regarding its tolerances for salinity and temperature. In this report, we provide data on the tolerance of A. ocellatus to abrupt and gradual changes in salinity, its high and low temperature tolerance, and information on how salinity, temperature, and fish size interact to affect survival. Fish were able to survive abrupt transfer to salinities as high as 16 ppt with no mortality. When salinity change was gradual (2 ppt/day), fish in the warm-temperature experiment (28°C) survived longer than fish in the cool-temperature experiment (18°C). Larger fish survived longer than smaller ones at the higher salinities when the temperature was warm, but when the temperature was cool fish size had little effect on survival. In the temperature-tolerance experiments, fish survived from 9 to 41°C for short periods of time. Overall, the species showed a wide range of temperature and salinity tolerance. Thus, in spite of the tropical freshwater origin of this species, physiological stress is not likely to hinder its dispersal to brackish waters, especially when temperatures are warm.
Response of fish population dynamics to mitigation activities in a large regulated river
Watkins, Carson J.; Ross, Tyler J.; Quist, Michael C.; Hardy, Ryan S.
2017-01-01
Extensive water development in large rivers has precipitated many negative ecological effects on native fish populations. Mitigation for such development often focuses on restoring biological integrity through remediation of the physical and chemical properties of regulated rivers. However, evaluating and defining the success of those programs can be difficult. We modeled the influence of mitigation-related environmental factors on growth and recruitment of two ecologically important native fish species (Largescale Sucker Catostomus macrocheilus and Mountain Whitefish Prosopium williamsoni) in the Kootenai River, Idaho. Artificial nutrient (phosphorus) addition best predicted the variability in annual growth of both species. Nutrient addition was positively related to Largescale Sucker growth but negatively related to Mountain Whitefish growth. The best model explained 82% of the annual variability in incremental growth for Largescale Suckers and 61% of the annual variability for Mountain Whitefish. Year-class strength of Largescale Suckers was not closely related to any of the environmental variables evaluated; however, year-class strength of Mountain Whitefish was closely associated with nutrient addition, discharge, and temperature. Most research has focused on biotic assemblages to evaluate the effects of mitigation activities on fishes, but there is an increased need to identify the influence of rehabilitation activities on fish population dynamics within those assemblages. Here, we demonstrate how fish growth can serve as an indicator of rehabilitation success in a highly regulated large river. Future fish restoration projects can likely benefit from a change in scope and from consideration of an evaluation framework involving the response of population rate functions to mitigation.
Scoppettone, G. Gary; Rissler, Peter; Johnson, Danielle; Hereford, Mark
2011-01-01
This study provides baseline data of native and non-native fish populations in Ash Meadows National Wildlife Refuge (NWR), Nye County, Nevada, that can serve as a gauge in native fish enhancement efforts. In support of Carson Slough restoration, comprehensive surveys of Ash Meadows NWR fishes were conducted seasonally from fall 2007 through summer 2008. A total of 853 sampling stations were created using Geographic Information Systems and National Agricultural Imagery Program. In four seasons of sampling, Amargosa pupfish (genus Cyprinodon) was captured at 388 of 659 stations. The number of captured Amargosa pupfish ranged from 5,815 (winter 2008) to 8,346 (summer 2008). The greatest success in capturing Amargosa pupfish was in warm water spring-pools with temperature greater than 25 degrees C, headwaters of warm water spring systems, and shallow (depths less than 10 centimeters) grassy marshes. In four seasons of sampling, Ash Meadows speckled dace (Rhinichthys osculus nevadesis) was captured at 96 of 659 stations. The number of captured Ash Meadows speckled dace ranged from 1,009 (summer 2008) to 1,552 (winter 2008). The greatest success in capturing Ash Meadows speckled dace was in cool water spring-pools with temperature less than 20 degrees C and in the high flowing water outflows. Among 659 sampling stations within the range of Amargosa pupfish, red swamp crayfish (Procambarus clarkii) was collected at 458 stations, western mosquitofish (Gambusia affinis) at 374 stations, and sailfin molly (Poecilia latipinna) at 128 stations. School Springs was restored during the course of this study. Prior to restoration of School Springs, maximum Warm Springs Amargosa pupfish (Cyprinodon nevadensis pectoralis) captured from the six springs of the Warm Springs Complex was 765 (fall 2007). In four seasons of sampling, Warm Springs Amargosa pupfish were captured at 85 of 177 stations. The greatest success in capturing Warm Springs Amargosa pupfish when co-occurring with red swamp crayfish and western mosquitofish was in water with temperature greater than 26 degrees C near the springhead, and in shallow (depths less than 10 centimeters) grassy marshes. Among 177 sampling stations within the range of Warm Springs Amargosa pupfish, red swamp crayfish were collected at 96 stations and western mosquitofish were collected at 49 stations. Removal of convict cichlid (Amatitlania nigrofasciata) from Fairbanks Spring was followed by a substantial increase in Ash Meadows Amargosa pupfish (Cyprinodon nevadensis mionectes) captures from 910 pre-removal to 3,056 post-removal. Red swamp crayfish was continually removed from Bradford 1 Spring, which seemed to cause an increase in the speckled dace population. Restoration of Kings Pool and Jackrabbit Springs promoted the success of native fishes with the greatest densities in restored reaches. Ongoing restoration of Carson Slough and its tributaries, as well as control and elimination of invasive species, is expected to increase abundance and distribution of Ash Meadows' native fish populations. Further analysis of data from this study will help determine the habitat characteristic(s) that promote native species and curtail non-native species.
Patterns of interactions of a large fish-parasite network in a tropical floodplain.
Lima, Dilermando P; Giacomini, Henrique C; Takemoto, Ricardo M; Agostinho, Angelo A; Bini, Luis M
2012-07-01
1. Describing and explaining the structure of species interaction networks is of paramount importance for community ecology. Yet much has to be learned about the mechanisms responsible for major patterns, such as nestedness and modularity in different kinds of systems, of which large and diverse networks are a still underrepresented and scarcely studied fraction. 2. We assembled information on fishes and their parasites living in a large floodplain of key ecological importance for freshwater ecosystems in the Paraná River basin in South America. The resulting fish-parasite network containing 72 and 324 species of fishes and parasites, respectively, was analysed to investigate the patterns of nestedness and modularity as related to fish and parasite features. 3. Nestedness was found in the entire network and among endoparasites, multiple-host life cycle parasites and native hosts, but not in networks of ectoparasites, single-host life cycle parasites and non-native fishes. All networks were significantly modular. Taxonomy was the major host's attribute influencing both nestedness and modularity: more closely related host species tended to be associated with more nested parasite compositions and had greater chance of belonging to the same network module. Nevertheless, host abundance had a positive relationship with nestedness when only native host species pairs of the same network module were considered for analysis. 4. These results highlight the importance of evolutionary history of hosts in linking patterns of nestedness and formation of modules in the network. They also show that functional attributes of parasites (i.e. parasitism mode and life cycle) and origin of host populations (i.e. natives versus non-natives) are crucial to define the relative contribution of these two network properties and their dependence on other ecological factors (e.g. host abundance), with potential implications for community dynamics and stability. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.
Muhlfeld, Clint C.; D'Angelo, Vincent S.; S. T. Kalinowski,; Landguth, Erin L.; C. C. Downs,; J. Tohtz,; Kershner, Jeffrey L.
2012-01-01
Biologists are often faced with the difficult decision in managing native salmonids of where and when to install barriers as a conservation action to prevent upstream invasion of nonnative fishes. However, fine-scale approaches to assess long-term persistence of populations within streams and watersheds chosen for isolation management are often lacking. We employed a spatially-explicit approach to evaluate stream habitat conditions, relative abundance, and genetic diversity of native westslope cutthroat trout (Oncorhynchus clarkii lewisi) within the Akokala Creek watershed in Glacier National Park- a population threatened by introgressive hybridization with nonnative rainbow trout (O. mykiss) from nearby sources. The systematic survey of 24 stream reaches showed broad overlap in fish population and suitable habitat characteristics among reaches and no natural barriers to fish migration were found. Analysis of population structure using 16 microsatellite loci showed modest amounts of genetic diversity among reaches, and that fish from Long Bow Creek were the only moderately distinct genetic group. We then used this information to assess the potential impacts of three barrier placement scenarios on long-term population persistence and genetic diversity. The two barrier placement scenarios in headwater areas generally failed to meet general persistence criteria for minimum population size (2,500 individuals, Ne = 500), maintenance of long-term genetic diversity (He), and no population subdivision. Conversely, placing a barrier near the stream mouth and selectively passing non-hybridized, migratory spawners entering Akokala Creek met all persistence criteria and may offer the best option to conserve native trout populations and life history diversity. Systematic, fine-scale stream habitat, fish distribution, and genetic assessments in streams chosen for barrier installation are needed in conjunction with broader scale assessments to understand the potential impacts of using barriers for conservation of native salmonid populations threatened by nonnative fish invasions.
Investigating phenology of larval fishes in St. Louis River estuary shallow water habitats
As part of the development of an early detection monitoring strategy for non-native fishes, larval fish surveys have been conducted since 2012 in the St. Louis River estuary. Survey data demonstrates there is considerable variability in fish abundance and species assemblages acro...
77 FR 63294 - Endangered and Threatened Species; Take of Anadromous Fish
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-16
... and Threatened Species; Take of Anadromous Fish AGENCY: National Marine Fisheries Service (NMFS... Klallam Tribe and the Washington Department of Fish and Wildlife have submitted five Hatchery and Genetic... programs are currently operating, and all five hatchery programs raise fish native to the Elwha River basin...
NASA Astrophysics Data System (ADS)
Waltmunson, Jeremy C.
2005-07-01
This study has investigated the L2 acquisition of Spanish word-medial /d, t, r, (fish hook)/, word-initial /r/, and onset cluster /(fish hook)/. Two similar experiments were designed to address the relative degree of difficulty of the word-medial contrasts, as well as the effect of word-position on /r/ and /(fish hook)/ accuracy scores. In addition, the effect of vowel height on the production of [r] and the L2 emergence of the svarabhakti vowel in onset cluster /(fish hook)/ were investigated. Participants included 34 Ll English speakers from a range of L2 Spanish levels who were recorded in multiple sessions across a 6-month or 2-month period. The criteria for assessing segment accuracy was based on auditory and acoustic features found in productions by native Spanish speakers. In order to be scored as accurate, the L2 productions had to evidence both the auditory and acoustic features found in native speaker productions. L2 participant scores for each target were normalized in order to account for the variation of features found across native speaker productions. The results showed that word-medial accuracy scores followed two significant rankings (from lowest to highest): /r <= d <= (fish hook) <= t/ and /r <= (fish hook) <= d <= t/; however, when scores for /t/ included a voice onset time criterion, only the ranking /r <= (fish hook) <= d <= t/ was significant. These results suggest that /r/ is most difficult for learners while /t/ is least difficult, although individual variation was found. Regarding /r/, there was a strong effect of word position and vowel height on accuracy scores. For productions of /(fish hook)/, there was a strong effect of syllable position on accuracy scores. Acoustic analyses of taps in onset cluster revealed that only the experienced L2 Spanish participants demonstrated svarabhakti vowel emergence with native-like performance, suggesting that its emergence occurs relatively late in L2 acquisition.
Brown, Elizabeth J.; Cassell, John S.; Donihe, Michele M.; Duffing Romero, Mareike D.; Duke, Mara A.; Green, Damon; Hillbrand, Paul; Wilson Grimes, Kristin R.; Nemeth, Richard S.; Smith, Tyler B.; Brandt, Marilyn
2017-01-01
Caribbean seagrass habitats provide food and protection for reef-associated juvenile fish. The invasive seagrass Halophila stipulacea is rapidly altering these seascapes. Since its arrival in the Caribbean in 2002, H. stipulacea has colonized and displaced native seagrasses, but the function of this invasive seagrass as a juvenile fish habitat remains unknown. To compare diversity, community structure, and abundance of juvenile fish between H. stipulacea and native seagrass beds, fish traps were deployed in four nearshore bays around St. Thomas, U.S. Virgin Islands. Traps were deployed in Frenchman, Lindbergh, and Sprat Bays for 24 h intervals in patches of bare sand, patches of H. stipulacea and patches of the native Caribbean seagrasses Thalassia testudinum and Syringodium filiforme. Traps were then deployed in Brewers Bay for 12 h intervals in stands of H. stipulacea and S. filiforme. Relative and total abundances of juvenile fish, identified at least to family, were compared across treatment habitats for each trap deployment period. The catch from H. stipulacea, compared to native seagrasses, comprised a greater abundance of nocturnal carnivores Lutjanus synagris (family Lutjanidae) and Haemulon flavolineatum (family Haemulidae). Additionally, the herbivore species Sparisoma aurofrenatum (family Labridae) and Acanthurus bahianus (family Acanthuridae) and the diurnal carnivore species Pseudopeneus maculatus (family Mullidae) were relatively scarce in H. stipulacea. The catch from sand was much smaller, compared to vegetated habitats, and comprised only L. synagris, H. flavolineatum, and H. aurolineatum. These results provide evidence of reduced family diversity and altered juvenile fish assemblages in H. stipulacea, driven by an abundance of some nocturnal carnivores and scarcity of herbivores and diurnal carnivores. The findings from the present work underpin the need for further investigation and mitigation of this invasion, particularly where H. stipulacea is driving seascape-alterations of key juvenile fish habitats. PMID:29161322
Founding population size of an aquatic invasive species
Kalinowski, Steven T.; Muhlfeld, Clint C.; Guy, Christopher S.; Benjamin Cox,
2010-01-01
Non-native species of fish threaten native fishes throughout North America, and in the Rocky Mountains, introduced populations of lake trout threaten native populations of bull trout. Effective management of lake trout and other exotic species require understanding the dynamics of invasion in order to either suppress non-native populations or to prevent their spread. In this study, we used microsatellite genetic data to estimate the number of lake trout that invaded a population of bull trout in Swan Lake, MT. Examination of genetic diversity and allele frequencies within the Swan Lake populations showed that most of the genes in the lake trout population are descended from two founders. This emphasizes the importance of preventing even a few lake trout from colonizing new territory.
Melis, Theodore S.; Pine, William E.; Korman, Josh; Yard, Michael D.; Jain, Shaleen; Pulwarty, Roger S.; Miller, Kathleen; Hamlet, Alan F.; Kenney, Douglas S.; Redmond, Kelly T.
2016-01-01
Adaptive management of Glen Canyon Dam is improving downstream resources of the Colorado River in Glen Canyon National Recreation Area and Grand Canyon National Park. The Glen Canyon Dam Adaptive Management Program (AMP), a federal advisory committee of 25 members with diverse special interests tasked to advise the U.S. Department of the Interior), was established in 1997 in response to the 1992 Grand Canyon Protection Act. Adaptive management assumes that ecosystem responses to management policies are inherently complex and unpredictable, but that understanding and management can be improved through monitoring. Best known for its high-flow experiments intended to benefit physical and biological resources by simulating one aspect of pre-dam conditions—floods, the AMP promotes collaboration among tribal, recreation, hydropower, environmental, water and other natural resource management interests. Monitoring has shown that high flow experiments move limited new tributary sand inputs below the dam from the bottom of the Colorado River to shorelines; rebuilding eroded sandbars that support camping areas and other natural and cultural resources. Spring-timed high flows have also been shown to stimulate aquatic productivity by disturbing the river bed below the dam in Glen Canyon. Understanding about how nonnative tailwater rainbow trout (Oncorhynchus mykiss), and downstream endangered humpback chub (Gila cypha) respond to dam operations has also increased, but this learning has mostly posed “surprise” adaptation opportunities to managers. Since reoperation of the dam to Modified Low Fluctuating Flows in 1996, rainbow trout now benefit from more stable daily flows and high spring releases, but possibly at a risk to humpback chub and other native fishes downstream. In contrast, humpback chub have so far proven robust to all flows, and native fish have increased under the combination of warmer river temperatures associated with reduced storage in Lake Powell, and a system-wide reduction in trout from 2000-06, possibly due to several years of natural reproduction under limited food supply. Uncertainties about dam operations and ecosystem responses remain, including how native and nonnative fish will interact and respond to possible increased river temperatures under drier basin conditions. Ongoing assessment of operating policies by the AMP’s diverse stakeholders represents a major commitment to the river’s valued resources, while surprise learning opportunities can also help identify a resilient climate-change strategy for co-managing nonnative and endangered native fish, sandbar habitats and other river resources in a region with already complex and ever-increasing water demands.
Metrics for assessing freshwater fish in Narragansett Bay
Freshwater fish are ecologically important in stream ecosystems, and they provide significant value to humans. Historically, the streams and rivers of southern New England supported moderately diverse and abundant assemblages of native fishes. Currently, these habitats are impact...
NASA Astrophysics Data System (ADS)
Laffont, Laure; Sonke, Jeroen; Maurice, Laurence; Behra, Philippe
2010-05-01
Mercury contamination is an environmental problem in the Amazon basin still relevant today as impacts on human health are poorly studied. In Bolivia, indigenous people have elevated methylmercury concentrations (between 2719 and 23701 ng.g-1) in their hair. This highly toxic molecule is formed after methylation of inorganic Hg released by chemical and physical weathering and from human activities. The aim of our study is to propose a first isotope balance in a Bolivian Amazon ecosystem, through variations in Hg isotopic compositions. The discovery of mass-independent fracionation (MIF) of odd-isotopes in our organic samples (fish and human hair) opened a new way of research in tracing the sources and the processes involved in the cycle of Hg. Four types of samples are studied: liquid Hg0 from gold mining, sediment samples, fish coming from the Beni River basin (from the main channel and an associated floodplain lake) and hair from gold miners and fish-eating native populations. Hg isotopic compositions were analyzed on a Thermo-Finnigan Neptune MC-ICP-MS at the LMTG after sample digestion by HCl/HNO3 or by H2O2/HNO3 for fish samples, at 120°C. The δ202Hg values (relative to NIST 3133) are signicantly different with respect to the external precision on UM-Almaden#2 of 0.18 ‰ (2σ, n = 42): -0.34 ± 0.02 ‰ for liquid mercury, between -1.33 and -0.81 ‰ for bottom and floodplain sediments (n=18), between -0.87 and 2.22 ‰ for miners hair (n=26), +1.29 ± 0.41 ‰ for native hair (n=13) and between -0.91 and -0.21 ‰ for fish samples (n=53). A large mass-independent isotope fractionation (MIF) was observed for odd isotope ratios in all hair samples and fish samples whereas weak anomalies were measured for sediment samples: - ∆199Hg anomaly: -0.12 to -0.04 ‰ for sediment, -0.22 to +0.63 ‰ for fish samples and +0.13 to +1.63 ‰ for hair - ∆201Hg anomaly: -0.12 to -0.02 ‰ for sediment, -0.21 to +0.43 ‰ for fish samples and +0.06 to +1.25 ‰ for hair. Both anomalies ∆201Hg vs. ∆199Hg are linearly correlated with a slope of +1.12‰ for native hair and a mass dependant fractionation (MDF) of ~+2‰ has been evidenced between native communities hair and fish species constituting their diet. For the same fish species, MIF anomalies differ with floodplain lakes and drainage basins suggesting that the methylmercury (MMHg) analysed in fish caught in floodplain lake reflects the photodemethylation process while in the Beni R. mainstream the negative anomalies confirm that this photochemical reactions are limited. Within the aquatic food chain of an hydrosystem, it appears that MIF anomalies can trace the fish ecology and the aquatic photochemical processes, while mass dependent fractionation can trace the trophic level as a result of excretion and metabolic processes involving mercury in the body.
Bruce G. Marcot; Chris S. Allen; Steve Morey; Dan Shively; Rollie White
2012-01-01
The bull trout Salvelinus confluentus is an apex predator in native fish communities in the western USA and is listed as threatened under the U.S. Endangered Species Act (ESA). Restoration of this species has raised concerns over its potential predatory impacts on native fish fauna. We held a five-person expert panel to help determine potential...
Arcagni, Marina; Juncos, Romina; Rizzo, Andrea; Pavlin, Majda; Fajon, Vesna; Arribére, María A; Horvat, Milena; Ribeiro Guevara, Sergio
2018-01-15
Niche segregation between introduced and native fish in Lake Nahuel Huapi, a deep oligotrophic lake in Northwest Patagonia (Argentina), occurs through the consumption of different prey. Therefore, in this work we analyzed total mercury [THg] and methylmercury [MeHg] concentrations in top predator fish and in their main prey to test whether their feeding habits influence [Hg]. Results indicate that [THg] and [MeHg] varied by foraging habitat and they increased with greater percentage of benthic diet and decreased with pelagic diet in Lake Nahuel Huapi. This is consistent with the fact that the native creole perch, a mostly benthivorous feeder, which shares the highest trophic level of the food web with introduced salmonids, had higher [THg] and [MeHg] than the more pelagic feeder rainbow trout and bentho-pelagic feeder brown trout. This differential THg and MeHg bioaccumulation observed in native and introduced fish provides evidence to the hypothesis that there are two main Hg transfer pathways from the base of the food web to top predators: a pelagic pathway where Hg is transferred from water, through plankton (with Hg in inorganic species mostly), forage fish to salmonids, and a benthic pathway, as Hg is transferred from the sediments (where Hg methylation occurs mostly), through crayfish (with higher [MeHg] than plankton), to native fish, leading to one fold higher [Hg]. Copyright © 2017 Elsevier B.V. All rights reserved.
Forestry practices and aquatic biodiversity: Fish
Gresswell, Robert E.
2005-01-01
In the Pacific Northwest, fish communities are found in a diverse array of aquatic habitats ranging from the large coastal rivers of the temperate rainforests, to the fragmented and sometimes ephemeral streams of the xeric interior basins, and high-elevation streams and lakes in the mountainous areas (Rieman et al. 2003). Only high-elevation lakes and streams isolated above barriers to fish passage remained historically devoid of fish because they were never invaded following Pleistocene glaciation (Smith 1981). Despite this widespread distribution and once great population abundances, taxonomic diversity of fishes in these forested systems is naturally lower than in aquatic habitats in the eastern U.S. (Reeves, Bisson, and Dambacher 1998). Interactions among factors that influence species richness in aquatic systems (e.g., basin size, long-term stability of habitat, and barriers to colonization; Smith 1981) continue to influence the occurrence and persistence of fishes in these systems today. Consequently, the larger low-elevation rivers and estuaries support the greatest variety of fish species. In the high-elevation tributary streams, fish communities are less complex because these aquatic systems were less climatically and geologically stable, and fish populations were smaller and more prone to local extirpation. Furthermore, barriers to fish passage inhibited dispersal and colonization (Smith 1981). Streams in forested landscapes generally support salmon and trout, Oncorhynchus spp., whitefish Prosopium spp., sculpins Cottus spp., suckers Catostomus spp., and minnows (Cyprinidae), but in some of the colder streams, chars (e.g., Salvelinus confluentus and Salvelinus malma) and lampreys (Petromyzontidae)may also occur (Rieman et al. 2003).Although biodiversity defined in terms of fish species richness is low in the Pacific Northwest, intraspecific variability is high, and polytypic fish species are common in the diverse aquatic habitats of the region. For example, the salmonids in the coastal rivers and streams, and the larger interconnected streams, rivers, and lakes of the interior exhibit a variety of ecotypes and migratory life histories (Healey 1986; Trotter 1989; Larson and McIntire 1993; Northcote 1997). This life-history variation appears to be associated with adaptation to spatial and temporal variation in environment (e.g., Schaffer and Elson 1975; Carl and Healey 1984; Beacham and Murray 1987), and there is some evidence of the genetic heritability of life-history traits (Carl and Healey 1984; Gharrett and Smoker 1993; Hankin, Nicholas, and Downey 1993). Persistence of any level of biological organization (e.g., life-history type, population, metapopulation, subspecies, species, community) is related to the interaction of environmental and biological components, and intraspecific diversity is a means of spreading risk (sensu den Boer 1968) of extirpation in dynamic environments (Gresswell 1999). Unfortunately, despite the broad distribution and extensive intraspecific diversity, persistence of native fishes is uncertain in the Pacific Northwest. Many populations of anadromous salmonids, once synonymous with vigorous biological communities throughout the region, are threatened with extinction (Nehlsen, Williams, and Lichatowich 1991; Frissell 1993; Thurow, Lee, and Rieman 1997). Furthermore, over half of the native taxa in the Columbia River Basin are either listed under the Endangered Species Act, are being considered for listing, or are deemed sensitive by the management agencies (Lee et al. 1997; Thurow, Lee, and Rieman 1997). Potamodromous species like bull trout Salvelinus confluentus are estimated to occur as strong populations in less than 5% of their potential range (Rieman, Lee, and Thurow 1997). Although not currently listed under the endangered species list, the coastal cutthroat trout Oncorhynchus clarki is managed as a sensitive species in Oregon and California (Hall, Bisson, and Gresswell 1997). Native non-game fishes have rarely been monitored, but populations of species such as large-scale suckers (Catostomus macrocheilus), squawfish (Ptychocheilus umpquae), and Pacific lamprey (Lampetra tridentata) also are declining in some drainages (Oregon Department of Fish and Wildlife, unpublished data).
Kurt D. Fausch; Bruce E. Rieman; Jason B. Dunham; Michael K. Young; Douglas P. Peterson
2009-01-01
Conservation biologists often face the trade-off that increasing connectivity in fragmented landscapes to reduce extinction risk of native species can foster invasion by non-native species that enter via the corridors created, which can then increase extinction risk. This dilemma is acute for stream fishes, especially native salmonids, because their populations are...
Re-cycling mercury: the role of stocking non-native fish in high-altitude lakes
NASA Astrophysics Data System (ADS)
Hansson, S. V.; Le Roux, G.; Sonke, J.
2016-12-01
Mercury (Hg) is a globally distributed pollutant that can be carried long distances and be deposited remote from its original source. It is also one of the few natural abundant trace metals that serves no biological purpose, i.e. is highly toxic to humans and other biota. Studies have also shown that Hg-deposition increases with increasing altitude, leading to a higher load of contamination to these already sensitive environments. Any additional sources of Hg to high-altitude aquatic systems are therefore of high concern. Today introduced non-indigenous fish can be found in aquatic systems on all contents, with the exception of Antarctica. However, the social and economic benefits gained by these introductions often weighs against the ecological impacts. E.g. studies have shown that introduction of carnivore fish can lead to alternation of the aquatic food web and introduce pathogens causing population declines or even extinction. Few studies however have looked at the introduction of non-native fish to high altitude aquatic systems in the scope of heavy-metal contamination. By using a combined geochemical and isotopic approach, we therefore study the introduction of brown trout as a potential source of Hg-contamination in three high altitude lakes in the French Pyrenees. We combine analysis of δ13C and δ15N, with tot-Hg and Hg-isotopes in samples of biofilm, invertebrates, common minnow and brow trout and compare these with data from trout bred at a local fish farm, providing the fish used when stocking lakes in the nearby region. Our results show that levels of tot-Hg in trout from our sites surpasses literature values by 5 times or more and that MIF and MDF Hg-isotope signatures shows clear relationship with fish size and with δ15N. However, there is a clear difference in the Hg-isotopic signatures of the wild trout compared to the farmed. Whereas δ202Hg and Δ199Hg-signatures of the wild trout aligns with the onsite food chain (biofilm, plankton, common minnow), the farmed trout show isotopic signatures identical to marine biota, e.g. tuna and dolphin. This is also reflected in the δ15N-signatures where the farmed trout corresponds to trophic levels two steps above those of the wild trout. Drawing on these data we therefore ask; are we recycling mercury and shortcutting the natural Hg-cycle by stocking lakes with farmed fish?
Creative Photography - Wildlife
2016-03-25
A bald eagle surveys its surroundings from a high treetop at NASA’s Kennedy Space Center in Florida. The spaceport shares borders with the Merritt Island National Wildlife Refuge, which is home to more than 330 native and migratory bird species, along with 25 mammal, 117 fish, and 65 amphibian and reptile species.
76 FR 584 - Glen Canyon Dam Adaptive Management Program Work Group (AMWG)
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-05
... 2010 expenditures, (2) updates on High Flow Experimental Protocol and the Non-native Fish Control... Group (AMWG) AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The... committee, the Adaptive Management Work Group (AMWG), a technical work group (TWG), a Grand Canyon...
Re-examining the relationship between invasive lionfish and native grouper in the Caribbean.
Valdivia, Abel; Bruno, John F; Cox, Courtney E; Hackerott, Serena; Green, Stephanie J
2014-01-01
Biotic resistance is the idea that native species negatively affect the invasion success of introduced species, but whether this can occur at large spatial scales is poorly understood. Here we re-evaluated the hypothesis that native large-bodied grouper and other predators are controlling the abundance of exotic lionfish (Pterois volitans/miles) on Caribbean coral reefs. We assessed the relationship between the biomass of lionfish and native predators at 71 reefs in three biogeographic regions while taking into consideration several cofactors that may affect fish abundance, including among others, proxies for fishing pressure and habitat structural complexity. Our results indicate that the abundance of lionfish, large-bodied grouper and other predators were not negatively related. Lionfish abundance was instead controlled by several physical site characteristics, and possibly by culling. Taken together, our results suggest that managers cannot rely on current native grouper populations to control the lionfish invasion.
Re-examining the relationship between invasive lionfish and native grouper in the Caribbean
Bruno, John F.; Cox, Courtney E.; Hackerott, Serena; Green, Stephanie J.
2014-01-01
Biotic resistance is the idea that native species negatively affect the invasion success of introduced species, but whether this can occur at large spatial scales is poorly understood. Here we re-evaluated the hypothesis that native large-bodied grouper and other predators are controlling the abundance of exotic lionfish (Pterois volitans/miles) on Caribbean coral reefs. We assessed the relationship between the biomass of lionfish and native predators at 71 reefs in three biogeographic regions while taking into consideration several cofactors that may affect fish abundance, including among others, proxies for fishing pressure and habitat structural complexity. Our results indicate that the abundance of lionfish, large-bodied grouper and other predators were not negatively related. Lionfish abundance was instead controlled by several physical site characteristics, and possibly by culling. Taken together, our results suggest that managers cannot rely on current native grouper populations to control the lionfish invasion. PMID:24765582
Tropical insular fish assemblages are resilient to flood disturbance
Smith, William E.; Kwak, Thomas J.
2015-01-01
Periods of stable environmental conditions, favoring development of ecological communities regulated by density-dependent processes, are interrupted by random periods of disturbance that may restructure communities. Disturbance may affect populations via habitat alteration, mortality, or displacement. We quantified fish habitat conditions, density, and movement before and after a major flood disturbance in a Caribbean island tropical river using habitat surveys, fish sampling and population estimates, radio telemetry, and passively monitored PIT tags. Native stream fish populations showed evidence of acute mortality and downstream displacement of surviving fish. All fish species were reduced in number at most life stages after the disturbance, but populations responded with recruitment and migration into vacated upstream habitats. Changes in density were uneven among size classes for most species, indicating altered size structures. Rapid recovery processes at the population level appeared to dampen effects at the assemblage level, as fish assemblage parameters (species richness and diversity) were unchanged by the flooding. The native fish assemblage appeared resilient to flood disturbance, rapidly compensating for mortality and displacement with increased recruitment and recolonization of upstream habitats.
Jiang, Wan-Sheng; Qin, Tao; Wang, Wei-Ying; Zhao, Ya-Peng; Shu, Shu-Sen; Song, Wei-Hong; Chen, Xiao-Yong; Yang, Jun-Xing
2016-09-18
Biological invasion is a pervasive negative force of global change, especially in its effects on sensitive freshwater ecosystems. Even protected areas are usually not immune. Ptychobarbus chungtienensis is a threatened freshwater fish now almost confined to Bita Lake, in the Shangri-La region of Yunnan province, China. Its existence is threatened by the introduction of non-native weatherfishes (Misgurnus anguillicaudatus and Paramisgurnus dabryanus) by an unusual method known as 'prayer animal release'. Periodic surveys revealed the ratio of invasive weatherfishes to P. chungtienensis has been increasing since the former species was first recorded from the lake in August, 2009. Ptychobarbus chungtienensis shows low genetic diversity in the relict Lake Bita population. Weatherfishes, however, have highly successful survival strategies. The degree of dietary overlap between the species is alarming and perhaps critical if food is found to be a limiting factor.
Could high salinity be used to control bullfrogs in small ponds?
Ward, David L.; Finch, Colton; Blasius, Heidi
2015-01-01
We examined survival of bullfrog (Rana catesbeiana) eggs and tadpoles at 3 ppt and 6 ppt salinity in the laboratory to determine if low-level salinity could be used to eradicate bullfrogs from small ponds that contain native fishes. Bullfrog eggs and tadpoles <10 days old experienced 100% mortality when held at 6 ppt salinity for 10 days. Bullfrog tadpoles 10–15 days old experienced significantly reduced survival when exposed to salinity of 6 ppt for 10 days. Older bullfrog tadpoles (>9 months old) appeared unaffected by 14 days of 6 ppt salinity. Salinity of 3 ppt did not impact survival of bullfrog tadpole eggs or tadpoles at any of the life stages we tested. Adding salt to ponds in the early spring to increase salinity to 6 ppt may be a cost effective way to eradicate bullfrogs from small ponds without harming native fishes.
Panek, Frank M.; Atkinson, James; Coll, John
2008-01-01
Restrictive fish stocking policies in National Parks were developed as early as 1936 in order to preserve native fish assemblages and historic genetic diversity. Despite recent efforts to understand the effects of non-native or exotic fish introductions, park managers have limited information regarding the effects of these introductions on native fish communities. Shenandoah National Park was established in 1936 and brook trout (Salvelinus fontinalis) restoration within selected streams in the park began in 1937 in collaboration with the Virginia Department of Game and Inland Fisheries (VDGIF). An analysis of tissue samples from brook, brown (Salmo trutta), and rainbow trout (Oncorhynchus mykiss) from 29 streams within the park from 1998–2002 revealed the presence of Renibacterium salmoninarum, Yersinia ruckeri, and infectious pancreatic necrosis virus (IPNv). In order to investigate the relationships of the occurrence of fish pathogens with stocking histories we classified the streams into three categories: 1) streams with no record of stocking, 2) streams that are known to have been stocked historically, and 3) streams that were historically stocked within the park and continue to be stocked downstream of the park boundary. The occurrences of pathogens were summarized relative to this stocking history. Renibacterium salmoninarum, the causative agent of bacterial kidney disease, was the most prevalent pathogen found, occurring in all three species and stream stocking categories, and appears to be endemic to the park. Two other pathogens, Yersinia ruckeri and infectious pancreatic necrosis virus were also described from brook trout populations within the park. IPNv was only found in brook trout populations in streams with prior stocking histories. Yersinia ruckeri was only found in brook trout in steams that have never been stocked and like R. salmoninarum, is likely endemic.
Hierarchical spatial structure of stream fish colonization and extinction
Hitt, N.P.; Roberts, J.H.
2012-01-01
Spatial variation in extinction and colonization is expected to influence community composition over time. In stream fish communities, local species richness (alpha diversity) and species turnover (beta diversity) are thought to be regulated by high extinction rates in headwater streams and high colonization rates in downstream areas. We evaluated the spatiotemporal structure of fish communities in streams originally surveyed by Burton and Odum 1945 (Ecology 26: 182-194) in Virginia, USA and explored the effects of species traits on extinction and colonization dynamics. We documented dramatic changes in fish community structure at both the site and stream scales. Of the 34 fish species observed, 20 (59%) were present in both time periods, but 11 (32%) colonized the study area and three (9%) were extirpated over time. Within streams, alpha diversity increased in two of three streams but beta diversity decreased dramatically in all streams due to fish community homogenization caused by colonization of common species and extirpation of rare species. Among streams, however, fish communities differentiated over time. Regression trees indicated that reproductive life-history traits such as spawning mound construction, associations with mound-building species, and high fecundity were important predictors of species persistence or colonization. Conversely, native fishes not associated with mound-building exhibited the highest rates of extirpation from streams. Our results demonstrate that stream fish colonization and extinction dynamics exhibit hierarchical spatial structure and suggest that mound-building fishes serve as keystone species for colonization of headwater streams.
Brown, L.R.
2000-01-01
Twenty sites in the lower San Joaquin River drainage, California, were sampled from 1993 to 1995 to characterize fish communities and their associations with measures of water quality and habitat quality. The feasibility of developing an Index of Biotic Integrity was assessed by evaluating four fish community metrics, including percentages of native fish, omnivorous fish, fish intolerant of environmental degradation, and fish with external anomalies. Of the thirty-one taxa of fish captured during the study, only 10 taxa were native to the drainage. Multivariate analyses of percentage data identified four site groups characterized by different groups of species. The distributions of fish species were related to specific conductance, gradient, and mean depth; however, specific conductance acted as a surrogate variable for a large group of correlated variables. Two of the fish community metrics - percentage of introduced fish and percentage of intolerant fish - appeared to be responsive to environmental quality but the responses of the other two metrics - percentage of omnivorous fish and percentage of fish with anomalies - were less direct. The conclusion of the study is that fish communities are responsive to environmental conditions, including conditions associated with human-caused disturbances, particularly agriculture and water development. The results suggest that changes in water management and water quality could result in changes in species distributions. Balancing the costs and benefits of such changes poses a considerable challenge to resource managers.
Brown, Larry R.
1998-01-01
Twenty sites in the lower San Joaquin River drainage, California, were sampled from 1993 to 1995 to characterize fish assemblages and their associations with measures of water quality and habitat quality. In addition, four fish community metrics were assessed, including percentages of native fish, omnivorous fish, fish intolerant of environmental degradation, and fish with external anomalies. Of the 31 taxa of fish captured during the study, only 10 taxa were native to the drainage. Multivariate analyses of percentage data identified four site groups characterized by characterized by different groups of species. The distributions of fish species were related to specific conductance, gradient, and mean depth; however, specific conductance acted as a surrogate variable for a large group of correlated variables. Two of the fish community metrics--percentage of introduced fish and percentage of intolerant fish--appeared to be responsive to environmental quality but the responses of the other two metrics--percentage of omnivorous fish and percentage of fish with anomalies--were less direct. The conclusion of the study is that fish assemblages are responsive to environmental conditions, including conditions associated with human-caused disturbances, particularly agriculture and water development. The results suggest that changes in water management and water quality could result in changes in species distributions. Balancing the costs and benefits of such changes poses a considerable challenge to resource managers. different groups of species.
Brennan, Reid S; Hwang, Ruth; Tse, Michelle; Fangue, Nann A; Whitehead, Andrew
2016-06-01
Regulation of internal ion homeostasis is essential for fishes inhabiting environments where salinities differ from their internal concentrations. It is hypothesized that selection will reduce energetic costs of osmoregulation in a population's native osmotic habitat, producing patterns of local adaptation. Killifish, Fundulus heteroclitus, occupy estuarine habitats where salinities range from fresh to seawater. Populations inhabiting an environmental salinity gradient differ in physiological traits associated with acclimation to acute salinity stress, consistent with local adaptation. Similarly, metabolic rates differ in populations adapted to different temperatures, but have not been studied in regard to salinity. We investigated evidence for local adaptation between populations of killifish native to fresh and brackish water habitats. Aerobic scope (the difference between minimum and maximum metabolic rates), excess post-exercise oxygen consumption, and swimming performance (time and distance to reach exhaustion) were used as proxies for fitness in fresh and brackish water treatments. Swimming performance results supported local adaptation; fish native to brackish water habitats performed significantly better than freshwater-native fish at high salinity while low salinity performance was similar between populations. However, results from metabolic measures did not support this conclusion; both populations showed an increase in resting metabolic rate and a decrease of aerobic scope in fresh water. Similarly, excess post-exercise oxygen consumption was higher for both populations in fresh than in brackish water. While swimming results suggest that environmentally dependent performance differences may be a result of selection in divergent osmotic environments, the differences between populations are not coupled with divergence in metabolic performance. Copyright © 2016 Elsevier Inc. All rights reserved.
[Historical presence of invasive fish in the biosphere reserve sierra de Huautla, Mexico].
Mejía-Mojica, Humberto; de Rodríguez-Romero, Felipe Jesús; Díaz-Pardo, Edmundo
2012-06-01
The effects of invasive species on native ecosystems are varied, and these have been linked to the disappearance or decline of native fauna, changes in community structure, modification of ecosystems and as vectors of new diseases and parasites. Besides, the development of trade in species for ornamental use has contributed significantly to the import and introduction of invasive fish in some important areas for biodiversity conservation in Mexico, but the presence of these species is poorly documented. In this study we analyzed the fish community in the Biosphere Reserve Sierra de Huautla by looking at diversity changes in the last 100 years. For this, we used databases of historical records and recent collections for five sites in the Amacuzac river, along the Biosphere Reserve area. We compared the values of similarity (Jaccard index) between five times series (1898-1901, 1945-1953, 1971-1980, 1994-1995 and 2008-2009), and we obtained values of similarity (Bray-Curtis) between the five sites analyzed. In our results we recognized a total of 19 species for the area, nine non-native and ten native, three of which were eliminated for the area. Similarity values between the early days and current records were very low (.27); the major changes in the composition of the fauna occurred in the past 20 years. The values of abundance, diversity and similarity among the sampling sites, indicate the dominance of non-native species. We discuss the role of the ornamental fish trade in the region as the leading cause of invasive introduction in the ecosystem and the possible negative effects that at least four non-native species have had on native fauna and the ecosystem (Oreochromis mossambicus, Amatitlania nigrofasciata, Pterygoplichthys disjunctivus and P pardalis). There is an urgent need of programs for registration, control and eradication of invasive species in the Sierra de Huautla Biosphere Reserve and biodiversity protection areas in Mexico.
C. O. Minckley
2013-01-01
San Bernardino Creek is a northern tributary of the RÃo Yaqui that originates in the United States and crosses the International Border just east of Douglas, Arizona/Agua Prieta, Sonora and immediately south of San Bernardino/Leslie Canyon National Wildlife Refuge. Six of eight RÃo Yaqui native fishes occur in this reach:four minnows, a sucker, and a poeciliid....
50 CFR 100.10 - Federal Subsistence Board.
Code of Federal Regulations, 2011 CFR
2011-10-01
... for the conservation of healthy populations of fish or wildlife, to continue subsistence uses of fish..., Native organizations, local governmental entities, and other persons and organizations, including...
Cervantes-Yoshida, Kristina; Leidy, Robert A.; Carlson, Stephanie M.
2015-01-01
Urbanization is one of the leading threats to freshwater biodiversity, and urban regions continue to expand globally. Here we examined the relationship between recent urbanization and shifts in stream fish communities. We sampled fishes at 32 sites in the Alameda Creek Watershed, near San Francisco, California, in 1993–1994 and again in 2009, and we quantified univariate and multivariate changes in fish communities between the sampling periods. Sampling sites were classified into those downstream of a rapidly urbanizing area (“urbanized sites”), and those found in less impacted areas (“low-impacted sites”). We calculated the change from non-urban to urban land cover between 1993 and 2009 at two scales for each site (the total watershed and a 3km buffer zone immediately upstream of each site). Neither the mean relative abundance of native fish nor nonnative species richness changed significantly between the survey periods. However, we observed significant changes in fish community composition (as measured by Bray-Curtis dissimilarity) and a decrease in native species richness between the sampling periods at urbanized sites, but not at low-impacted sites. Moreover, the relative abundance of one native cyprinid (Lavinia symmetricus) decreased at the urbanized sites but not at low-impacted sites. Increased urbanization was associated with changes in the fish community, and this relationship was strongest at the smaller (3km buffer) scale. Our results suggest that ongoing land change alters fish communities and that contemporary resurveys are an important tool for examining how freshwater taxa are responding to recent environmental change. PMID:26580560
NASA Astrophysics Data System (ADS)
Mouzon, N. R.; Null, S. E.
2014-12-01
Human impacts from land and water development have degraded water quality and altered the physical, chemical, and biological integrity of Nevada's Walker River. Reduced instream flows and increased nutrient concentrations affect native fish populations through warm daily stream temperatures and low nightly dissolved oxygen concentrations. Water rights purchases are being considered to maintain instream flows, improve water quality, and enhance habitat for native fish species, such as Lahontan cutthroat trout. This study uses the River Modeling System (RMSv4), an hourly, physically-based hydrodynamic and water quality model, to estimate streamflows, temperatures, and dissolved oxygen concentrations in the Walker River. We simulate thermal and dissolved oxygen changes from increased streamflow to prioritize the time periods and locations that water purchases most enhance native trout habitat. Stream temperatures and dissolved oxygen concentrations are proxies for trout habitat. Monitoring results indicate stream temperature and dissolved oxygen limitations generally exist in the 115 kilometers upstream of Walker Lake (about 37% of the study area) from approximately May through September, and this reach currently acts as a water quality barrier for fish passage.
50 CFR 18.23 - Native exemptions.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Native exemptions. 18.23 Section 18.23 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED... PLANTS (CONTINUED) MARINE MAMMALS General Exceptions § 18.23 Native exemptions. (a) Taking. Except as...
50 CFR 18.23 - Native exemptions.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Native exemptions. 18.23 Section 18.23 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED... PLANTS (CONTINUED) MARINE MAMMALS General Exceptions § 18.23 Native exemptions. (a) Taking. Except as...
50 CFR 18.23 - Native exemptions.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Native exemptions. 18.23 Section 18.23 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED... PLANTS (CONTINUED) MARINE MAMMALS General Exceptions § 18.23 Native exemptions. (a) Taking. Except as...
50 CFR 18.23 - Native exemptions.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Native exemptions. 18.23 Section 18.23 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED... PLANTS (CONTINUED) MARINE MAMMALS General Exceptions § 18.23 Native exemptions. (a) Taking. Except as...
Massie, Danielle L.; Smith, Geoffrey; Bonvechio, Timothy F.; Bunch, Aaron J.; Lucchesi, David O.; Wagner, Tyler
2018-01-01
Quantifying spatial variability in fish growth and identifying large‐scale drivers of growth are fundamental to many conservation and management decisions. Although fish growth studies often focus on a single population, it is becoming increasingly clear that large‐scale studies are likely needed for addressing transboundary management needs. This is particularly true for species with high recreational value and for those with negative ecological consequences when introduced outside of their native range, such as the Flathead Catfish Pylodictis olivaris. This study quantified growth variability of the Flathead Catfish across a large portion of its contemporary range to determine whether growth differences existed between habitat types (i.e., reservoirs and rivers) and between native and introduced populations. Additionally, we investigated whether growth parameters varied as a function of latitude and time since introduction (for introduced populations). Length‐at‐age data from 26 populations across 11 states in the USA were modeled using a Bayesian hierarchical von Bertalanffy growth model. Population‐specific growth trajectories revealed large variation in Flathead Catfish growth and relatively high uncertainty in growth parameters for some populations. Relatively high uncertainty was also evident when comparing populations and when quantifying large‐scale patterns. Growth parameters (Brody growth coefficient [K] and theoretical maximum average length [L∞]) were not different (based on overlapping 90% credible intervals) between habitat types or between native and introduced populations. For populations within the introduced range of Flathead Catfish, latitude was negatively correlated with K. For native populations, we estimated an 85% probability that L∞ estimates were negatively correlated with latitude. Contrary to predictions, time since introduction was not correlated with growth parameters in introduced populations of Flathead Catfish. Results of this study suggest that Flathead Catfish growth patterns are likely shaped more strongly by finer‐scale processes (e.g., exploitation or prey abundances) as opposed to macro‐scale drivers.
Carpenter, J.
2005-01-01
Crayfish are not native to the Colorado River basin (CRB), however they are now established in portions of the mainstem and in many tributaries. I used density manipulation experiments in a laboratory setting to determine intra- and interspecific competition for food between Orconectes virilis, an aggressive polytrophic crayfish now common in the CRB, and two native fishes: Gila chub, Gila intermedia, and flannelmouth sucker, Catostomus latipinnis. I tested each fish species in separate trials. Growth of Gila chub decreased when animal densities increased, however they were more affected by intraspecific competition than by crayfish presence. In contrast, growth of flannelmouth suckers was more affected by crayfish than by intraspecific competition. Crayfish growth was not significantly altered by presence of either fish. Crayfish thus reduced fish growth by competition for food, but the effect differed markedly between the two species.
Korman, Josh; Kaplinski, Matthew; Melis, Theodore S.
2011-01-01
Hourly fluctuations in flow from Glen Canyon Dam were increased in an attempt to limit the population of nonnative rainbow trout Oncorhynchus mykiss in the Colorado River, Arizona, due to concerns about negative effects of nonnative trout on endangered native fishes. Controlled floods have also been conducted to enhance native fish habitat. We estimated that rainbow trout incubation mortality rates resulting from greater fluctuations in flow were 23-49% (2003 and 2004) compared with 5-11% under normal flow fluctuations (2006-2010). Effects of this mortality were apparent in redd excavations but were not seen in hatch date distributions or in the abundance of the age-0 population. Multiple lines of evidence indicated that a controlled flood in March 2008, which was intended to enhance native fish habitat, resulted in a large increase in early survival rates of age-0 rainbow trout. Age-0 abundance in July 2008 was over fourfold higher than expected given the number of viable eggs that produced these fish. A hatch date analysis indicated that early survival rates were much higher for cohorts that hatched about 1 month after the controlled flood (~April 15) relative to those that hatched before this date. The cohorts that were fertilized after the flood were not exposed to high flows and emerged into better-quality habitat with elevated food availability. Interannual differences in age-0 rainbow trout growth based on otolith microstructure supported this hypothesis. It is likely that strong compensation in survival rates shortly after emergence mitigated the impact of incubation losses caused by increases in flow fluctuations. Control of nonnative fish populations will be most effective when additional mortality is applied to older life stages after the majority of density-dependent mortality has occurred. Our study highlights the need to rigorously assess instream flow decisions through the evaluation of population-level responses.
Mitigation for the Construction and Operation of Libby Dam, 2004-2005 Annual Report.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dunnigan, James; DeShazer, Jay; Garrow, Larry
2005-06-01
''Mitigation for the Construction and Operation of Libby Dam'' is part of the Northwest Power and Conservation Council's (NPCC) resident fish and wildlife program. The program was mandated by the Northwest Planning Act of 1980, and is responsible for mitigating damages to fish and wildlife caused by hydroelectric development in the Columbia River Basin. The objective of Phase I of the project (1983 through 1987) was to maintain or enhance the Libby Reservoir fishery by quantifying seasonal water levels and developing ecologically sound operational guidelines. The objective of Phase II of the project (1988 through 1996) was to determine themore » biological effects of reservoir operations combined with biotic changes associated with an aging reservoir. The objectives of Phase III of the project (1996 through present) are to implement habitat enhancement measures to mitigate for dam effects, to provide data for implementation of operational strategies that benefit resident fish, monitor reservoir and river conditions, and monitor mitigation projects for effectiveness. This project completes urgent and high priority mitigation actions as directed by the Kootenai Subbasin Plan. Montana Fish, Wildlife & Parks (MFWP) uses a combination of techniques to collect physical and biological data within the Kootenai River Basin. These data serve several purposes including: the development and refinement of models used in management of water resources and operation of Libby Dam; investigations into the limiting factors of native fish populations, gathering basic life history information, tracking trends in endangered and threatened species, and the assessment of restoration or management activities designed to restore native fishes and their habitats.« less
Copaja, S V; Muñoz, G S; Nuñez, V R; Pérez, C; Vila, I; Véliz, D
2016-07-01
In order to determine the effect of a dam on metal concentrations in riverine fish species, we studied fish inhabiting the influent (Cachapoal River) and effluent (Rapel River) of the Rapel Reservoir in central Chile. Heavy metals were quantified in gills, liver and muscle of the catfish Trichomycterus areolatus and the silverside Basilichthys microlepidotus. Also, the bioaccumulation index (BAI) was estimated by considering heavy metal concentrations obtained from water and sediment. Results showed the presence of Al, Cu, Fe, Mn, Pb and Zn in the fish organs. The analysis showed high metal concentrations in catfish inhabiting the influent compared to those collected in the effluent. These results indicate a possible filter effect of the dam for most of the metals identified in the fish organs, because metal concentrations decreased in the effluent. Finally, catfish exhibited a larger BAI for most metals analyzed.
Woodward, Andrea; Hollar, Kathy
2011-01-01
The U.S. Fish and Wildlife Service's (FWS) Pacific Region (Region 1) includes more than 158 million acres (almost 247,000 square miles) of land base in Idaho, Oregon, Washington, Hawai`i, the Commonwealth of the Northern Mariana Islands, American Samoa, Guam, the Republic of Palau, the Federated States of Micronesia, and the Republic of the Marshall Islands. Region 1 is ecologically diverse with landscapes that range from coral reefs, broadleaf tropical forests, and tropical savannahs in the Pacific Islands, to glacial streams and lakes, lush old-growth rainforests, inland fjords, and coastal shoreline in the Pacific Northwest, to the forested mountains, shrub-steppe desert, and native grasslands in the Inland Northwest. Similarly, the people of the different landscapes perceive, value, and manage their natural resources in ways unique to their respective regions and cultures. The Partners for Fish and Wildlife Program (Partners Program) and Coastal Program work with a variety of partners in Region 1 including individual landowners, watershed councils, land trusts, Soil and Water Conservation Districts, non-governmental organizations, Tribal governments, Native Hawaiian organizations, and local, State, and Federal agencies. The Partners Program is the FWS's vanguard for working with private landowners to voluntarily restore and conserve fish and wildlife habitat. Using non-regulatory incentives, the Partners Program engages willing partners to conserve and protect valuable fish and wildlife habitat on their property and in their communities. This is accomplished by providing the funding support and technical and planning tools needed to make on-the-ground conservation affordable, feasible, and effective. The primary goals of the Pacific Region Partners Program are to: Promote citizen and community-based stewardship efforts for fish and wildlife conservation Contribute to the recovery of at-risk species, Protect the environmental integrity of the National Wildlife Refuges, Contribute to the implementation of the State Comprehensive Wildlife Conservation Strategies, and Help achieve the objectives of the National Fish Habitat Partnerships and regionally based bird conservation plans (for example, North American Waterfowl Management Plan, U.S. Pacific Island Shorebird Conservation Plans, Intermountain West Regional Shorebird Plan, etc.). The Partners Program accomplishes these priorities by: Developing and maintaining strong partnerships, and delivering on-the-ground habitat restoration projects designed to reestablish habitat function and restore natural processes; Addressing key habitat limiting factors for declining species; Providing corridors for wildlife and decrease impediments to native fish and wildlife migration; and Enhancing native plant communities by reducing invasive species and improving native species composition. The Coastal Program is a voluntary fish and wildlife conservation program that focuses on watershed-scale, long-term collaborative resource planning and on-the-ground restoration projects in high-priority coastal areas. The Coastal Program conducts planning and restoration work on private, State, and Federal lands, and partnerships with other agencies-Native American Tribes, citizens, and organizations are emphasized. Coastal Program goals include restoring and protecting coastal habitat, providing technical and cost-sharing assistance where appropriate, supporting community-based restoration, collecting and developing information on the status of and threats to fish and wildlife, and using outreach to promote stewardship of coastal resources. The diversity of habitats and partners in Region 1 present many opportunities for conducting restoration projects. Faced with this abundance of opportunity, the Partners Program and Coastal Program must ensure that limited staffing and project dollars are allocated to benefit the highest priority resources and achieve the highest quality results for Federal trust species. In 2007, the Partners Program and Coastal Program developed a Strategic Plan to guide program operations and more efficiently conserve habitat by focusing partnership building and habitat improvement actions within 35 Partners Program Focus Areas and 9 Coastal Program Focus Areas (U.S. Fish and Wildlife Service, 2010). The Strategic Plan also contains four other goals: broaden and strengthen partnerships; improve information sharing and communications; enhance workforce; and increase accountability to ensure that program resources are used efficiently and effectively. This protocol will help achieve all goals of the Strategic Plan.
NASA Astrophysics Data System (ADS)
Cobián-Rojas, Dorka; Schmitter-Soto, Juan J.; Aguilar Betancourt, Consuelo M.; Aguilar-Perera, Alfonso; Ruiz-Zárate, Miguel Á.; González-Sansón, Gaspar; Chevalier Monteagudo, Pedro P.; Herrera Pavón, Roberto; García Rodríguez, Alain; Corrada Wong, Raúl I.; Cabrera Guerra, Delmis; Salvat Torres, Héctor; Perera Valderrama, Susana
2018-04-01
Marine protected areas (MPAs) conserve diversity and abundance of fish communities. According to the biotic resistance hypothesis, communities with higher diversity and abundance should resist invasions better. To test this idea, the presence of lionfish in two Caribbean MPAs was studied: Parque Nacional Guanahacabibes (PNG) in Cuba and Parque Nacional Arrecifes de Xcalak (PNAX) in Mexico. Selection of these MPAs was based on both their different levels of success with enforcement and different abundances of native fish, with a more abundant native fish fauna at PNG. Underwater visual censuses were used to evaluate both the native fish structure and composition and at the same time distribution and abundance of lionfish. The abundance of potential predators on lionfish was also measured to determine possible effects of lionfish on both the abundance and the size of its prey and competitors. Lionfish showed higher abundance and larger size in PNG compared to PNAX, even though its probable competitors and predators were also more abundant and larger in PNG. Prey abundance and size decreased after the invasion. No correlation was detected between potential predators and lionfish, which might indicate natural predation is not substantial. In PNAX, lower abundance of prey, potential competitors and predators can also be attributed to historical overfishing, but this did not provide an advantage to lionfish. Lionfish were less abundant and reached smaller sizes in PNAX compared to PNG. This work confirms the effectiveness of lionfish culling at PNAX, but does not support the biotic resistence hypothesis that native fish might have controlled this invasive species.
Budy, Phaedra; Gaeta, Jereme W.; Lobón-Cerviá, Javier; Sanz, Nuria
2017-01-01
Brown trout are one of the most pervasive and successful invaders worldwide and are ubiquitous across the Intermountain West, USA (IMW). This species is the foundation of extremely popular and economically significant sport fisheries despite well-established negative effects on native fishes and ecosystems, resulting in very challenging, and often opposing, conservation and management goals. Herein, we review the direct (e.g., competition and predation) and indirect (e.g., disease vectors) pathways through which brown trout across the IMW have posed a threat to native species. We discuss the importance of brown trout as economically and culturally important fisheries, especially in novel tailwater ecosystems created by damming. To this end, we surveyed 24 experts from eight states across the IMW to document the relevance of novel brown trout fisheries in 51 tailwaters and found brown trout are thriving in these novel ecosystems, which are often unsuitable for native fishes. We discuss the challenging interplay between protecting native species and managing novel brown trout fisheries. Notably, the future of exotic brown trout in the IMW is shifting as the prestige of native fisheries is growing and many non-native eradication efforts have occurred. The future of exotic brown trout in the IMW, will depend on the nexus of public sentiment and policy, the effectiveness of eradication efforts, and the effect of climate change on both the native fishes and exotic brown trout. Regardless, because brown trout are pervasive and have a broad distribution through the IMW, populations of this species will likely persist at least in some locations into the future.
Schofield, Pamela J.; Peterson, Mark S.; Lowe, Michael R.; Brown-Peterson, Nancy J.; Slack, William T.
2011-01-01
The physiological tolerances of non-native fishes is an integral component of assessing potential invasive risk. Salinity and temperature are environmental variables that limit the spread of many non-native fishes. We hypothesised that combinations of temperature and salinity will interact to affect survival, growth, and reproduction of Nile tilapia, Oreochromis niloticus, introduced into Mississippi, USA. Tilapia withstood acute transfer from fresh water up to a salinity of 20 and survived gradual transfer up to 60 at typical summertime (30°C) temperatures. However, cold temperature (14°C) reduced survival of fish in saline waters ≥10 and increased the incidence of disease in freshwater controls. Although fish were able to equilibrate to saline waters in warm temperatures, reproductive parameters were reduced at salinities ≥30. These integrated responses suggest that Nile tilapia can invade coastal areas beyond their point of introduction. However, successful invasion is subject to two caveats: (1) wintertime survival depends on finding thermal refugia, and (2) reproduction is hampered in regions where salinities are ≥30. These data are vital to predicting the invasion of non-native fishes into coastal watersheds. This is particularly important given the predicted changes in coastal landscapes due to global climate change and sea-level rise.
Simon, Andrea; Britton, Robert; Gozlan, Rodolphe; van Oosterhout, Cock; Volckaert, Filip A. M.; Hänfling, Bernd
2011-01-01
The Asian cyprinid fish, the topmouth gudgeon (Pseudorasbora parva), was introduced into Europe in the 1960s. A highly invasive freshwater fish, it is currently found in at least 32 countries outside its native range. Here we analyse a 700 base pair fragment of the mitochondrial cytochrome b gene to examine different models of colonisation and spread within the invasive range, and to investigate the factors that may have contributed to their invasion success. Haplotype and nucleotide diversity of the introduced populations from continental Europe was higher than that of the native populations, although two recently introduced populations from the British Isles showed low levels of variability. Based on coalescent theory, all introduced and some native populations showed a relative excess of nucleotide diversity compared to haplotype diversity. This suggests that these populations are not in mutation-drift equilibrium, but rather that the relative inflated level of nucleotide diversity is consistent with recent admixture. This study elucidates the colonisation patterns of P. parva in Europe and provides an evolutionary framework of their invasion. It supports the hypothesis that their European colonisation was initiated by their introduction to a single location or small geographic area with subsequent complex pattern of spread including both long distance and stepping-stone dispersal. Furthermore, it was preceded by, or associated with, the admixture of genetically diverse source populations that may have augmented its invasive-potential. PMID:21674031
Code of Federal Regulations, 2011 CFR
2011-07-01
... these regulations. (b) State fishing licenses are not required in Big Bend, Crater Lake, Denali, Glacier... data indicate that the introduction of additional numbers or types of non-native species would not...
Code of Federal Regulations, 2012 CFR
2012-07-01
... these regulations. (b) State fishing licenses are not required in Big Bend, Crater Lake, Denali, Glacier... data indicate that the introduction of additional numbers or types of non-native species would not...
Code of Federal Regulations, 2013 CFR
2013-07-01
... these regulations. (b) State fishing licenses are not required in Big Bend, Crater Lake, Denali, Glacier... data indicate that the introduction of additional numbers or types of non-native species would not...
Code of Federal Regulations, 2014 CFR
2014-07-01
... these regulations. (b) State fishing licenses are not required in Big Bend, Crater Lake, Denali, Glacier... data indicate that the introduction of additional numbers or types of non-native species would not...
Strecker, Angela L.; Olden, Julian D.
2014-01-01
Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. We quantify phylogenetic clustering and overdispersion of native and non-native fishes of a large river basin in the American Southwest to test for the mechanisms (environmental filtering versus competitive exclusion) and spatial scales influencing community structure. Contrary to expectations, non-native species were phylogenetically clustered and related to natural environmental conditions, whereas native species were not phylogenetically structured, likely reflecting human-related changes to the basin. The species that are most invasive (in terms of ecological impacts) tended to be the most phylogenetically divergent from natives across watersheds, but not within watersheds, supporting the hypothesis that Darwin's naturalization conundrum is driven by the spatial scale. Phylogenetic distinctiveness may facilitate non-native establishment at regional scales, but environmental filtering restricts local membership to closely related species with physiological tolerances for current environments. By contrast, native species may have been phylogenetically clustered in historical times, but species loss from contemporary populations by anthropogenic activities has likely shaped the phylogenetic signal. Our study implies that fundamental mechanisms of community assembly have changed, with fundamental consequences for the biogeography of both native and non-native species. PMID:24452027
Larvivorous fish for preventing malaria transmission
Walshe, Deirdre P; Garner, Paul; Abdel-Hameed Adeel, Ahmed A; Pyke, Graham H; Burkot, Tom
2013-01-01
Background Adult anopheline mosquitoes transmit Plasmodium parasites that cause malaria. Some fish species eat mosquito larvae and pupae. In disease control policy documents, the World Health Organization includes biological control of malaria vectors by stocking ponds, rivers, and water collections near where people live with larvivorous fish to reduce Plasmodium parasite transmission. The Global Fund finances larvivorous fish programmes in some countries, and, with increasing efforts in eradication of malaria, policy makers may return to this option. We therefore assessed the evidence base for larvivorous fish programmes in malaria control. Objectives Our main objective was to evaluate whether introducing larvivorous fish to anopheline breeding sites impacts Plasmodium parasite transmission. Our secondary objective was to summarize studies evaluating whether introducing larvivorous fish influences the density and presence of Anopheles larvae and pupae in water sources, to understand whether fish can possibly have an effect. Search methods We attempted to identify all relevant studies regardless of language or publication status (published, unpublished, in press, or ongoing). We searched the following databases: the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL), published in The Cochrane Library; MEDLINE; EMBASE; CABS Abstracts; LILACS; and the metaRegister of Controlled Trials (mRCT) until 18 June 2013. We checked the reference lists of all studies identified by the above methods. We also examined references listed in review articles and previously compiled bibliographies to look for eligible studies. Selection criteria Randomized controlled trials and non-randomized controlled trials, including controlled before-and-after studies, controlled time series and controlled interrupted time series studies from malaria-endemic regions that introduced fish as a larvicide and reported on malaria in the community or the density of the adult anopheline population. In the absence of direct evidence of an effect on transmission, we carried out a secondary analysis on studies that evaluated the effect of introducing larvivorous fish on the density or presence of immature anopheline mosquitoes (larvae and pupae forms) in community water sources to determine whether this intervention has any potential in further research on control of malaria vectors. Data collection and analysis Three review authors screened abstracts and examined potentially relevant studies by using an eligibility form. Two review authors independently extracted data and assessed risk of bias of included studies. If relevant data were unclear or were not reported, we wrote to the trial authors for clarification. We presented data in tables, and we summarized studies that evaluated the effects of fish introduction on anopheline immature density or presence, or both. We used GRADE to summarize evidence quality. We also examined whether the authors of included studies reported on any possible adverse impact of larvivorous fish introduction on non-target native species. Main results We found no reliable studies that reported the effects of introducing larvivorous fish on malaria infection in nearby communities, on entomological inoculation rate, or on adult Anopheles density. For the secondary analysis, we examined the effects of introducing larvivorous fish on the density and presence of anopheline larvae and pupae in community water sources. We included 12 small studies, with follow-up from 22 days to five years. Studies were conducted in a variety of settings, including localized water bodies (such as wells, domestic water containers, fishponds, and pools; six studies), riverbed pools below dams (two studies), rice field plots (three studies), and water canals (two studies). All studies were at high risk of bias. The research was insufficient to determine whether larvivorous fish reduce the density of Anopheles larvae and pupae (nine studies, unpooled data, very low quality evidence). Some studies with high stocking levels of fish seemed to arrest the increase in immature anopheline populations, or to reduce the number of immature anopheline mosquitoes, compared with controls. However, this finding was not consistent, and in studies that showed a decrease in immature anopheline populations, the effect was not consistently sustained. Larvivorous fish may reduce the number of water sources withAnopheles larvae and pupae (five studies, unpooled data, low quality evidence). None of the included studies reported effects of larvivorous fish on local native fish populations or other species. Authors' conclusions Reliable research is insufficient to show whether introducing larvivorous fish reduces malaria transmission or the density of adult anopheline mosquito populations. In research examining the effects on immature anopheline stages of introducing fish to potential malaria vector breeding sites (localized water bodies such as wells and domestic water sources, rice field plots, and water canals) weak evidence suggests an effect on the density or presence of immature anopheline mosquitoes with high stocking levels of fish, but this finding is by no means consistent. We do not know whether this translates into health benefits, either with fish alone or with fish combined with other vector control measures. Our interpretation of the current evidence is that countries should not invest in fish stocking as a larval control measure in any malaria transmission areas outside the context of carefully controlled field studies or quasi-experimental designs. Research could also usefully examine the effects on native fish and other non-target species. PLAIN LANGUAGE SUMMARY Fish that feed on mosquito larvae for preventing malaria transmission Plasmodium parasites cause malaria and are transmitted by adult Anopheles mosquitoes. Programmes that introduce fish into water sources near where people live have been promoted. The theory is that these fish eat the Anopheles mosquito larvae and pupae, thus decreasing the adult mosquito population and reducing the number of people infected with Plasmodium parasites. In this review, we examined the research that evaluated introducing larvivorous fish to Anopheles mosquito breeding sites in areas where malaria was common, published up to 18 June 2013. We did not find any studies that looked at the effects of larvivorous fish on adult Anopheles mosquito populations or on the number of people infected with Plasmodium parasites. We included 12 studies that examined the effects of larvivorous fish on Anopheles larvae and pupae in different breeding sites, including localized water bodies (such as wells, domestic water containers, fishponds, and pools; six studies), riverbed pools below dams (two studies), rice field plots (three studies), and water canals (two studies). Research evidence is insufficient to show whether introduction of larvivorous fish reduces the number of Anopheles larvae and pupae in water sources (nine studies, unpooled data, very low quality evidence). However, larvivorous fish may reduce the number of water sources withAnopheles mosquito larvae and pupae (five studies, unpooled data, low quality evidence). None of the included studies examined the effects of introducing larvivorous fish on other native species present, but these studies were not designed to do this. Before much is invested in this intervention, better research is needed to determine the effect of introducing larvivorous fish on adult Anopheles populations and on the number of people infected with malaria. Researchers need to use robust controlled designs with an adequate number of sites. Also, researchers should explore whether introducing these fish affects native fish and other non-target species. PMID:24323308
DISTRIBUTIONS OF LAKE FISHES OF THE NORTHEAST USA--III. SALMONIDAE AND ASSOCIATED COLDWATER SPECIES
We present distributional maps and discuss native status for fish species characteristic of coldwater lakes, sampled from 203 randomly selected lakes in the northeastern USA (New England, New York, New Jersey). Eleven coldwater fish species from four families (Salmonidae, Osmeri...
Creative Photography - Wildlife
2016-03-25
With its wings raised and talons extended, a bald eagle touches down on a high treetop at NASA’s Kennedy Space Center in Florida. The spaceport shares borders with the Merritt Island National Wildlife Refuge, which is home to more than 330 native and migratory bird species, along with 25 mammal, 117 fish, and 65 amphibian and reptile species.
2015-01-01
Parasites can play an important role in biological invasions. While introduced species often lose parasites from their native range, they can also accumulate novel parasites in their new range. The accumulation of parasites by introduced species likely varies spatially, and more parasites may shift to new hosts where parasite diversity is high. Considering that parasitism and disease are generally more prevalent at lower latitudes, the accumulation of parasites by introduced hosts may be greater in tropical regions. The Indo-Pacific lionfish (Pterois volitans) has become widely distributed across the Western Atlantic. In this study, we compared parasitism across thirteen locations in four regions, spanning seventeen degrees of latitude in the lionfish's introduced range to examine potential spatial variation in parasitism. In addition, as an initial step to explore how indirect effects of parasitism might influence interactions between lionfish and ecologically similar native hosts, we also compared parasitism in lionfish and two co-occurring native fish species, the graysby grouper, Cephalopholis cruentata, and the lizardfish, Synodus intermedius, in the southernmost region, Panama. Our results show that accumulation of native parasites on lionfish varies across broad spatial scales, and that colonization by ectoparasites was highest in Panama, relative to the other study sites. Endoparasite richness and abundance, on the other hand, were highest in Belize where lionfish were infected by twice as many endoparasite species as lionfish in other regions. The prevalence of all but two parasite species infecting lionfish was below 25%, and we did not detect an association between parasite abundance and host condition, suggesting a limited direct effect of parasites on lionfish, even where parasitism was highest. Further, parasite species richness and abundance were significantly higher in both native fishes compared to lionfish, and parasite abundance was negatively associated with the condition index of the native grouper but not that of the lionfish or lizardfish. While two co-occurring native fishes were more heavily parasitized compared to lionfish in Panama any indirect benefits of differential parasitism requires further investigation. Future parasitological surveys of lionfish across the eastern coast of North America and the Lesser Antilles would further resolve geographic patterns of parasitism in invasive lionfish. PMID:26098309
de-Bashan, Luz E.; Hernandez, Juan-Pablo; Bashan, Yoav; Maier, Raina
2014-01-01
Three plant growth-promoting bacteria (PGPB; Bacillus pumilus ES4, B. pumilus RIZO1, and Azospirillum brasilense Cd) were tested for their ability to enhance plant growth and development of the native Sonoran Desert shrub quailbush (Atriplex lentiformis) and for their effect on the native bacterial community in moderately acidic, high-metal content (AHMT) and in neutral, low metal content natural tailings (NLMT) in controlled greenhouse experiments. Inoculation of quailbush with all three PGPB significantly enhanced plant growth parameters, such as germination, root length, dry weight of shoots and roots, and root/shoot ratio in both types of tailings. The effect of inoculation on the indigenous bacterial community by the most successful PGPB Bacillus pumilus ES4 was evaluated by denaturating gradient gel electrophoresis (PCR-DGGE) fingerprinting and root colonization was followed by specific fluorescent in situ hybridization (FISH). Inoculation with this strain significantly changed the bacterial community over a period of 60 days. FISH analysis showed that the preferred site of colonization was the root tips and root elongation area. This study shows that inoculation of native perennial plants with PGPB can be used for developing technologies for phytostabilizing mine tailings. PMID:25009362
Hereford, Mark E.
2016-07-22
The Amargosa River Canyon, located in the Mojave Desert of southeastern California, contains the longest perennial reach of the Amargosa River. Because of its diverse flora and fauna, it has been designated as an Area of Critical Environmental Concern and a Wild and Scenic River by the Bureau of Land Management. A survey of fishes conducted in summer 2010 indicated that endemic Amargosa River pupfish (Cyprinodon nevadensis amargosae) and speckled dace (Rhinichthys osculus spp.) were abundant and occurred throughout the Amargosa River Canyon. The 2010 survey reported non-native red swamp crayfish (Procambarus clarkii) and western mosquitofish (Gambusia affinis) captures were significantly higher, whereas pupfish captures were lower, in areas dominated by non-native saltcedar (Tamarix ssp.). Based on the 2010 survey, it was hypothesized that the invasion of saltcedar could result in a decrease in native species. In an effort to maintain and enhance native fish populations, the Bureau of Land Management removed saltcedar from a 1,550 meter reach of stream on the Amargosa River in autumn 2014 and autumn 2015. Prior to the removal of saltcedar, a survey of fishes and crayfish using baited minnow traps was conducted in the treatment reach to serve as a baseline for future comparisons with post-saltcedar removal surveys. During the 2014 survey, 1,073 pupfish and 960 speckled dace were captured within the treatment reach. Catch per unit effort of pupfish and speckled dace in the treatment reach was less in 2014 than in 2010, although differences could be owing to seasonal variation in capture probability. Non-native mosquitofish catch per unit effort decreased from 2010 to 2014; however, the catch per unit effort of crayfish increased from 2010 to 2014. Future monitoring efforts of this reach should be conducted at the same time period to account for potential seasonal fluctuations of abundance and distribution of fishes and crayfish. A more robust study design that accounts for variation in capture probability could be implemented to quantify the effects of habitat modifications on abundance of fishes and crayfish.
Long-term changes in the fish assemblage of a neotropical hydroelectric reservoir.
Orsi, M L; Britton, J R
2014-06-01
The changes in the fish assemblage of the Capivara Reservoir, Brazil, were assessed over a 20 year period. Of 50 native fishes present in the initial samples, 27 were no longer present in the final samples, but there had been an addition of 11 invasive fishes, suggesting the occurrence of substantial shifts in fish diversity and abundance. © 2014 The Fisheries Society of the British Isles.
Ryan K. Saylor,; Nicolas W.R. Laointe,; Angermeier, Paul
2012-01-01
Introductions of large, non-native, carnivorous fishes continue to occur worldwide and represent a substantial management concern to global biodiversity. One of the most recent non-native fishes to successfully establish in North America is the northern snakehead (Channa argus), found in the lower Potomac River catchment. Dispersal of the northern snakehead throughout this system has been well documented since its original discovery in May 2004; however, little is known about the foraging habits of this species and its interactions with co-occurring predators. Here, we quantify northern snakehead diet in comparison with the diets of naturalised largemouth bass (Micropterus salmoides), and native American eel (Anguilla rostrata) and yellow perch (Perca flavescens) collected from tidal freshwaters bordering Virginia and Maryland near Fort Belvoir, Virginia. Over 97% of northern snakehead gut contents were fishes, with fundulid and centrarchid species consumed most frequently. Dietary overlap was biologically significant only between northern snakehead and largemouth bass. Aquatic invertebrates were >10 times more common in native predator diets, reducing dietary overlap with northern snakehead. Ontogenic shifts in adult northern snakehead diet were also detected, which may be explained by optimal foraging rather than true prey specificity. Northern snakehead may be occupying a novel niche based on a piscivorous diet, therefore limiting competition with resident predators in the lower Potomac River. Further research into interactions between largemouth bass and northern snakehead is needed to inform management decisions and understand the ecological impacts of this non-native species.
Asian fish tapeworm Bothriocephalus acheilognathi in the desert southwestern United States.
Archdeacon, Thomas P; Iles, Alison; Kline, S Jason; Bonar, Scott A
2010-12-01
The Asian fish tapeworm Bothriocephalus acheilognathi (Cestoda: Bothriocephalidea) is an introduced fish parasite in the southwestern United States and is often considered a serious threat to native desert fishes. Determining the geographic distribution of nonnative fish parasites is important for recovery efforts of native fishes. We examined 1,140 individuals belonging to nine fish species from southwestern U.S. streams and springs between January 2005 and April 2007. The Asian fish tapeworm was present in the Gila River, Salt River, Verde River, San Pedro River, Aravaipa Creek, and Fossil Creek, Arizona, and in Lake Tuendae at Zzyzx Springs and Afton Canyon of the Mojave River, California. Overall prevalence of the Asian fish tapeworm in Arizona fish populations was 19% (range = 0-100%) and varied by location, time, and fish species. In California, the prevalence, abundance, and intensity of the Asian fish tapeworm in Mohave tui chub Gila bicolor mohavensis were higher during warmer months than during cooler months. Three new definitive host species--Yaqui chub G. purpurea, headwater chub G. nigra, and longfin dace agosia chrysogaster--were identified. Widespread occurrence of the Asian fish tapeworm in southwestern U.S. waters suggests that the lack of detection in other systems where nonnative fishes occur is due to a lack of effort as opposed to true absence of the parasite. To limit further spread of diseases to small, isolated systems, we recommend treatment for both endo- and exoparasites when management actions include translocation of fishes.
Composition and Use of Common Carp Meal as a Marine Fish Meal Replacement in Yellow Perch Diets
USDA-ARS?s Scientific Manuscript database
We evaluated the use of fish meal derived from a locally abundant, non-native fish species – common carp Cyprinus carpio – with the objective of offsetting the cost of marine fish meal (MFM, ~$1,200/ton) in yellow perch Perca flavescens feed. Biochemical analyses of meals showed that crude protein a...
Dodrill, Michael J.; Yard, Mike; Pine, William E.
2016-01-01
This study examined predation risk for juvenile native fish between two riverine shoreline habitats, backwater and debris fan, across three discrete turbidity levels (low, intermediate, high) to understand environmental risks associated with habitat use in a section of the Colorado River in Grand Canyon, AZ. Inferences are particularly important to juvenile native fish, including the federally endangered humpback chub Gila cypha. This species uses a variety of habitats including backwaters which are often considered important rearing areas. Densities of two likely predators, adult rainbow trout Oncorhynchus mykiss and adult humpback chub, were estimated between habitats using binomial mixture models to examine whether higher predator density was associated with patterns of predation risk. Tethering experiments were used to quantify relative predation risk between habitats and turbidity conditions. Under low and intermediate turbidity conditions, debris fan habitat showed higher relative predation risk compared to backwaters. In both habitats the highest predation risk was observed during intermediate turbidity conditions. Density of likely predators did not significantly differ between these habitats. This information can help managers in Grand Canyon weigh flow policy options designed to increase backwater availability or extant turbidity conditions.
Kennedy, Theodore A.; Cross, Wyatt F.; Hall, Robert O.; Baxter, Colden V.; Rosi-Marshall, Emma J.
2013-01-01
Fish populations in the Colorado River downstream from Glen Canyon Dam appear to be limited by the availability of high-quality invertebrate prey. Midge and blackfly production is low and nonnative rainbow trout in Glen Canyon and native fishes in Grand Canyon consume virtually all of the midge and blackfly biomass that is produced annually. In Glen Canyon, the invertebrate assemblage is dominated by nonnative New Zealand mudsnails, the food web has a simple structure, and transfers of energy from the base of the web (algae) to the top of the web (rainbow trout) are inefficient. The food webs in Grand Canyon are more complex relative to Glen Canyon, because, on average, each species in the web is involved in more interactions and feeding connections. Based on theory and on studies from other ecosystems, the structure and organization of Grand Canyon food webs should make them more stable and less susceptible to large changes following perturbations of the flow regime relative to food webs in Glen Canyon. In support of this hypothesis, Grand Canyon food webs were much less affected by a 2008 controlled flood relative to the food web in Glen Canyon.
The effects of cooking practices commonly used by Native Americans on total mercury concentrations in fish were investigated. A preparation factor relating mercury concentrations in fish as prepared for consumption to mercury concentration data as measured in typical environmenta...
Code of Federal Regulations, 2010 CFR
2010-07-01
... impact populations of native species adversely, and park management plans do not call for elimination of... time of catching the person did not possess the legal limit of fish. (8) Fishing from motor road bridges, from or within 200 feet of a public raft or float designated for water sports, or within the...
The northern pike, a prized native but disastrous invasive: Chapter 14
Rutz, David; Massengill, Robert L.; Sepulveda, Adam; Dunker, Kristine J.
2018-01-01
As the chapters in this book describe, the northern pike Esox lucius Linneaus, 1758 is a fascinating fish that plays an important ecological role in structuring aquatic communities (chapter 8), has the capacity to aid lake restoration efforts (chapter 11), and contributes substantially to local economies, both as a highlysought after sport fish (chapter 12) and as a commercial fishing resource (chapter 13). However, despite the magnificent attributes of this fish, there is another side to its story. Specifically, what happens when northern pike, a highly efficient predator, becomes established outside its natural range? To explore this question, this chapter will investigate observed consequences from many locations where northern pike (hereafter referred to as “pike”) have been introduced and discuss potential reasons why pike, under the right circumstances, can be considered an invasive species.
Emerald ash borer, black ash, and Native American basketmaking
Therese M. Poland; Marla R. Emery; Tina Ciaramitaro; Ed Pigeon; Angie Pigeon
2017-01-01
Native cultures coevolved with the forests of the Great Lakes region following the last ice age. Plentiful water, abundant game, and fertile soil supported fishing, hunting, and gathering, as well as subsistence agriculture. Lakes and tributaries facilitated transportation by canoe and trade among tribes. Native Americans developed a semi-nomadic lifestyle, moving...
Native Alaska's Floating Factoryship--She Plies the Pacific Ocean for Native Alaska.
ERIC Educational Resources Information Center
Wassaja, The Indian Historian, 1980
1980-01-01
Describes the history of the Al-Ind-Esk-A Sea, a floating fish processing factory representing a major hope for the economic independence of Alaska Natives residing outside the state. Discusses employment practices in effect on the ship. Notes interesting facts about the ship's engines and fittings. (SB)
Zimmerman, J.K.H.; Vondracek, B.
2006-01-01
We examined growth of native slimy sculpin (Cottus cognatus), native brook trout (Salvelinus fontinalis), and nonnative brown trout (Salmo trutta) to investigate potential interactions of a native nongame fish with native and nonnative trout. Enclosures (1 m2) were stocked with five treatments (juvenile brown trout with sculpin, juvenile brook trout with sculpin, and single species controls) at three densities. Treatments (with replication) were placed in riffles in Valley Creek, Minnesota, and growth rates were measured for six experiments. We examined the difference in growth of each species in combined species treatments compared with each species alone. We did not find evidence of interactions between brook trout and sculpin, regardless of density or fish size. However, sculpin gained greater mass when alone than with brown trout when sculpin were >16 g. Likewise, brown trout grew more when alone than with sculpin when brown trout were >24 g. In contrast, brown trout ???5 g grew more with sculpin compared with treatments alone. We suggest that native brook trout and sculpin coexist without evidence of competition, whereas nonnative brown trout may compete with sculpin. ?? 2006 NRC.
Monogeneans in introduced and native cichlids in México: evidence for transfer.
Jiménez-García, M I; Vidal-Martínez, V M; López-Jiménez, S
2001-08-01
We examined 2 cichlid fish species native to México, Cichlasoma callolepis and C. fenestratum, and 2 introduced African cichlids, Oreochromis aureus and O. niloticus, from 3 localities in southeastern México for monogeneans. Six monogenean species infected the African cichlids: Cichlidogyrus haplochromii, C. dossoui, C. longicornis longicornis, C. sclerosus, C. tilapiae, and Enterogyrus malmbergi. We found all these parasite species, except C. haplochromii and C. dossoui, on the native C. fenestratum and C. callolepis. Prevalences of Cichlidogyrus spp. were 3-10% and abundances ranged from 0.03 +/- 0.2 to 0.1 +/- 0.3 for native cichlids. We only recovered a single E. malmbergi from 1 C. callolepis. We found Sciadicleithrum bravohollisae, a monogenean of native Cichlasoma spp., on the gills of the introduced O. aureus from Lake Catemaco (prevalence 3%, abundance 0.03 +/- 0.2). Although prevalence and abundance in atypical hosts were fairly low, the present findings provide evidence of monogenean transfer from African to American cichlids and vice versa. This is the first record of exotic monogeneans in the genus Cichlidogyrus and Enterogyrus infecting native American cichlid fish. It is also the first record from southeastern México of a native American monogenean infecting introduced African cichlids.
Lorenz, O. Thomas; O' Connell, Martin T.; Schofield, Pamela J.
2010-01-01
The Rio Grande cichlid (Herichthys cyanoguttatus) has been established in the Greater New Orleans Metropolitan area for at least 20 years, and its effect on native fishes is unknown. Behavioral trials were performed to determine if aggressive interactions occur between invasive H. cyanoguttatus and native bluegill (Lepomis macrochirus). When defending a territory as the resident, L. macrochirus were markedly aggressive, averaging 11.6 aggressive actions per lO-min behavioral trial. In contrast, L. macrochirus were extremely passive as invaders, with 0.5 aggressive actions per trial. Herichthys cyanoguttatus were equally aggressive as residents and as invaders, averaging 4.9 and 6.0 aggressive actions per trial, respectively. Herichthys cyanoguttatus interacted aggressively with native species whether they held territory or not, indicating that this invasive species may have fundamentally different strategies of aggression compared with native L. macrochirus. These differences may explain the continued success of H. cyanoguttatus as an invasive fish in southeastern Louisiana.
Eastern mosquitofish resists invasion by nonindigenous poeciliids through agonistic behaviors
Thompson, Kevin A.; Hill, Jeffrey E.; Nico, Leo G.
2012-01-01
Florida is a hotspot for nonindigenous fishes with over 30 species established, although few of these are small-bodied species. One hypothesis for this pattern is that biotic resistance of native species is reducing the success of small-bodied, introduced fishes. The eastern mosquitofish Gambusia holbrooki is common in many freshwater habitats in Florida and although small-bodied (<50 mm), it is a predator and aggressive competitor. We conducted four mesocosm experiments to examine the potential for biotic resistance by eastern mosquitofish to two small-bodied nonindigenous fishes, variable platyfish (Xiphophorus variatus) and swordtail (X. hellerii). Experiments tested: (1) effect of eastern mosquitofish density on adult survival, (2) effect of eastern mosquitofish on a stage-structured population, (3) role of habitat structural complexity on nonindigenous adult survival, and (4) behavioral effects of eastern mosquitofish presence and habitat complexity. Eastern mosquitofish attacked and killed non-native poeciliids with especially strong effects on juveniles of both species. Higher eastern mosquitofish density resulted in greater effects. Predation on swordtails increased with increasing habitat complexity. Eastern mosquitofish also actively drove swordtails from cover, which could expose non-native fish to other predators under field conditions. Our results suggest that eastern mosquitofish may limit invasion success.
Warren, Dana R; Kraft, Clifford E; Josephson, Daniel C; Driscoll, Charles T
2017-06-01
From the 1970s to 1990s, more stringent air quality regulations were implemented across North America and Europe to reduce chemical emissions that contribute to acid rain. Surface water pH slowly increased during the following decades, but biological recovery lagged behind chemical recovery. Fortunately, this situation is changing. In the past few years, northeastern US fish populations have begun to recover in lakes that were historically incapable of sustaining wild fish due to acidic conditions. As lake ecosystems across the eastern United States recover from acid deposition, the stress to the most susceptible populations of native coldwater fish appears to be shifting from acidification effects to thermal impacts associated with changing climate. Extreme summer temperature events - which are expected to occur with increasing frequency in the coming century - can stress and ultimately kill native coldwater fish in lakes where thermal stratification is absent or highly limited. Based on data from northeastern North America, we argue that recovery from acid deposition has the potential to improve the resilience of coldwater fish populations in some lakes to impacts of climate change. This will occur as the amount of dissolved organic carbon (DOC) in the water increases with increasing lake pH. Increased DOC will reduce water clarity and lead to shallower and more persistent lake thermoclines that can provide larger areas of coldwater thermal refuge habitat. Recovery from acidification will not eliminate the threat of climate change to coldwater fish, but secondary effects of acid recovery may improve the resistance of coldwater fish populations in lakes to the effects of elevated summer temperatures in historically acidified ecosystems. This analysis highlights the importance of considering the legacy of past ecosystem impacts and how recovery or persistence of those effects may interact with climate change impacts on biota in the coming decades. © 2016 John Wiley & Sons Ltd.
Muhlfeld, C.C.; Bennett, D.H.; Kirk, Steinhorst R.; Marotz, B.; Boyer, M.
2008-01-01
Introductions of nonnative northern pike Esox lucius have created recreational fisheries in many waters in the United States and Canada, yet many studies have shown that introduced northern pike may alter the composition and structure of fish communities through predation. We estimated the abundance of nonnative northern pike (2002-2003) and applied food habits data (1999-2003) to estimate their annual consumption of native bull trout Salvelinus confluentus and westslope cutthroat trout Oncorhynchus clarkii lewisi juveniles in the upper Flathead River system, Montana. Population estimates were generally consistent among years and ranged from 1,200 to 1,300 individuals. Westslope cutthroat trout were present in the diet of younger (???600 mm) and older (>600 mm) northern pike during all seasons and bull trout were found only in larger northern pike during all seasons but summer. Bioenergetics modeling estimated that the northern pike population annually consumed a total of 8.0 metric tons (mt) of fish flesh; the highest biomass was composed of cyprinids (4.95 mt) followed by whitefishes Prosopium spp. (1.02 mt), bull trout (0.80 mt), westslope cutthroat trout (0.68 mt), yellow perch Perca flavescens (0.41 mt),1 and other fishes (centrarchids and cottids; 0.14 mt). Numerically, the northern pike population consumed more than 342,000 fish; cyprinids and catostomids comprised approximately 82% of prey fish (278,925), whereas over 13,000 westslope cutthroat trout and nearly 3,500 bull trout were eaten, comprising about 5% of the prey consumed. Our results suggest that predation by introduced northern pike is contributing to the lower abundance of native salmonids in the system and that a possible benefit might accrue to native salmonids by reducing these predatory interactions. ?? Copyright by the American Fisheries Society 2008.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vitale, Angelo; Roberts, Frank; Peters, Ronald
Throughout the last century, the cumulative effects of anthropogenic disturbances have caused drastic watershed level landscape changes throughout the Reservation and surrounding areas (Coeur d'Alene Tribe 1998). Changes include stream channelization, wetland draining, forest and palouse prairie conversion for agricultural use, high road density, elimination of old growth timber stands, and denuding riparian communities. The significance of these changes is manifested in the degradation of habitats supporting native flora and fauna. Consequently, populations of native fish, wildlife, and plants, which the Tribe relies on as subsistence resources, have declined or in some instances been extirpated (Apperson et al. 1988; Coeurmore » d'Alene Tribe 1998; Lillengreen et al. 1996; Lillengreen et al. 1993; Gerry Green Coeur d'Alene Tribe wildlife Biologist, personal communication 2002). For example, bull trout (Salvelinus confluentus) are not present at detectable levels in Reservation tributaries, westslope cutthroat trout (Oncorhynchus clarki lewisi) are not present in numbers commensurate with maintaining harvestable fisheries (Lillengreen et al. 1993, 1996), and the Sharp-tailed grouse (Tympanuchus phasianellus) are not present at detectable levels on the Reservation (Gerry Green, Coeur d'Alene Tribe wildlife biologist, personal communication). The Coeur d'Alene Tribe added Fisheries and Wildlife Programs to their Natural Resources Department to address these losses and protect important cultural, and subsistence resources for future generations. The Tribal Council adopted by Resolution 89(94), the following mission statement for the Fisheries Program: 'restore, protect, expand and re-establish fish populations to sustainable levels to provide harvest opportunities'. This mission statement, focused on fisheries restoration and rehabilitation, is a response to native fish population declines throughout the Tribe's aboriginal territory, including the Coeur d'Alene Indian Reservation (Coeur d'Alene Tribe 1998). Implicit in this statement is a commitment to provide native subsistence resources in the present and near future as well as the long-term by employing all the mitigation and conservation measures available to them. The development of this Habitat Protection Plan is intended to provide additional planning level guidance as the implementation of conservation measures moves forward. The purpose of this plan is to develop a systematic approach to habitat restoration that will ultimately lead to self-perpetuating, harvestable populations of native fish, wildlife and botanical species. Specifically, it is our intention to apply the principles and analyses presented in this plan to prioritize future restoration efforts that receive funding under the Northwest Power Planning Council's Resident Fish and Wildlife Mitigation Programs. Using an ecosystem restoration approach based on landscape ecology concepts (Primack 1993), the basic premise of the plan is to (1) protect functioning habitat conditions and (2) restore degraded habitat conditions. This plan focuses on habitat conditions at the watershed scale (macrohabitat) rather than on the needs of single species and/or species guilds. By focusing restoration efforts at a macrohabitat level, restoration efforts target all native species inhabiting that area. This approach marks a paradigm shift that emphasizes ecological based restoration rather than species-specific restoration. Traditionally, fish managers and wildlife managers have approached restoration independently, often dedicating resources to a single species by focusing on specific habitat types on a small spatial scale (microhabitat) (Robinson and Bolen 1989, Marcot et al. 2002). This management technique has done little to curb declines despite large budgets (Pianka 1994). Restoration on a landscape level has shown promising results (Holling 1992) and many riparian and wetland restoration projects throughout the northwest have inadvertently improved habitats for non-targeted species. Landscape level restoration addresses the overall habitat condition of the regional area (macrohabitat), restoring the native species composition, density, and diversity by restoring the native ecosystem function. In the context of the development and implementation of this Habitat Protection Plan, it is important to understand that this is primarily a conservation tool, and is not intended to displace efforts that mitigate for lost resources. This plan is intended to primarily address long-term conservation needs and may not accommodate immediate short-term needs that address lost resources. Therefore, areas selected to address short-term mitigation needs may not be located in the high priority areas identified in this Plan. It needs to be clear that these projects and areas are no less important than those identified in this Plan.« less
Using carbon dioxide in fisheries and aquatic invasive species management
Treanor, Hilary B.; Ray, Andrew M.; Layhee, Megan J.; Watten, Barnaby J.; Gross, Jason A.; Gresswell, Robert E.; Webb, Molly A. H.
2017-01-01
To restore native fish populations, fisheries programs often depend on active removal of aquatic invasive species. Chemical removal can be an effective method of eliminating aquatic invasive species, but chemicals can induce mortality in nontarget organisms and persist in the environment. Carbon dioxide (CO2) is an emerging alternative to traditional chemical control agents because it has been demonstrated to be toxic to fish, but is naturally occurring and readily neutralized. In addition, CO2 is a commercially available gas, is highly soluble, and has high absorption efficiency. When these characteristics are paired with advances in modern, large-scale gas delivery technologies, opportunities to use CO2 in natural or artificial (e.g., canals) waters to manage fish become increasingly feasible. Our objective is to describe the history of CO2 use in fisheries and outline potential future applications of CO2 to suppress and manipulate aquatic species in field and aquaculture settings.
Planning for the Future: Students Learn the Value of Resource Management Planning.
ERIC Educational Resources Information Center
Lynch, Karen
1994-01-01
Reports activities at the Native American Fish and Wildlife Society's annual National Inter-Tribal Youth Practicum held to enhance student interest in natural resource careers. This year, 94 high school students from tribes around the United States participated in the week-long experiential field exercise on the Yakima Reservation and prepared a…
Creative Photography - Wildlife
2016-03-25
A bald eagle raises its wings in preparation for takeoff from its high perch in a pine tree at NASA’s Kennedy Space Center in Florida. The spaceport shares borders with the Merritt Island National Wildlife Refuge, which is home to more than 330 native and migratory bird species, along with 25 mammal, 117 fish, and 65 amphibian and reptile species.
Burger, Joanna; Gochfeld, Michael
2010-01-01
A substantial body of literature deals with exposure differences between men and women, and how men and women perceive environmental risk, but far less attention has been devoted to how men and women use the environment and how they evaluate the features of natural environments. The objective of this study was to examine gender differences in the perceptions of environmental quality and resource use for Native Americans and Caucasians interviewed at an Indian festival in northwestern Idaho. More individuals engaged in fishing than any other consumptive activity, and more people engaged in camping and hiking than other nonconsumptive activities. For both ethnic groups, significantly more men hunted than women, although a higher percentage of Native Americans of both genders hunted than did Caucasians. Although significantly more Caucasian men fished than women (63 vs. 41%), there were no marked differences in fishing for Native Americans. Significantly more Native American women gathered herbs (57%) compared to men (37%). There were no significant gender differences in nonconsumptive activities (camping, hiking, biking, bird watching, or picnicking). For those who engaged in consumptive and nonconsumptive activities, however, there were few gender differences in the frequency of these activities, except for fishing, hunting, and crabbing by Caucasians (men had higher rates) and collecting berries and herbs for Native Americans (women had higher rates). When asked to evaluate environmental characteristics or attributes on a scale of 1 (less important) to 5 (very important), unpolluted water, clean air, no visible smog, unpolluted groundwater, and appears unspoiled were rated the highest. There were few significant gender differences in these evaluations for Native Americans, but there were significant gender differences for Caucasians: Women rated most features higher than did men (except for natural tidal flow). These data indicate a need to evaluate not only consumption rate differences between men and women, but also nonconsumptive activities, as well as resource values and perceptions, when managing environments and determining potential risk from exposure.
Impacts of exotic mangroves and mangrove control on tide pool fish assemblages
Richard A. MacKenzie; Cailtin L. Kryss
2013-01-01
Fish were sampled from tide pools in Hawaii to determine how exotic mangroves Rhizophora mangle and the use of herbicides to chemically eradicate them are impacting tide pool fish assemblages. Ecological parameters were compared among mangrove-invaded, native vegetated, and non-vegetated tide pools before and after mangroves had been chemically...
Environmental and Biotic Correlates to Lionfish Invasion Success in Bahamian Coral Reefs
Anton, Andrea; Simpson, Michael S.; Vu, Ivana
2014-01-01
Lionfish (Pterois volitans), venomous predators from the Indo-Pacific, are recent invaders of the Caribbean Basin and southeastern coast of North America. Quantification of invasive lionfish abundances, along with potentially important physical and biological environmental characteristics, permitted inferences about the invasion process of reefs on the island of San Salvador in the Bahamas. Environmental wave-exposure had a large influence on lionfish abundance, which was more than 20 and 120 times greater for density and biomass respectively at sheltered sites as compared with wave-exposed environments. Our measurements of topographic complexity of the reefs revealed that lionfish abundance was not driven by habitat rugosity. Lionfish abundance was not negatively affected by the abundance of large native predators (or large native groupers) and was also unrelated to the abundance of medium prey fishes (total length of 5–10 cm). These relationships suggest that (1) higher-energy environments may impose intrinsic resistance against lionfish invasion, (2) habitat complexity may not facilitate the lionfish invasion process, (3) predation or competition by native fishes may not provide biotic resistance against lionfish invasion, and (4) abundant prey fish might not facilitate lionfish invasion success. The relatively low biomass of large grouper on this island could explain our failure to detect suppression of lionfish abundance and we encourage continuing the preservation and restoration of potential lionfish predators in the Caribbean. In addition, energetic environments might exert direct or indirect resistance to the lionfish proliferation, providing native fish populations with essential refuges. PMID:25184250
Environmental and biotic correlates to lionfish invasion success in Bahamian coral reefs.
Anton, Andrea; Simpson, Michael S; Vu, Ivana
2014-01-01
Lionfish (Pterois volitans), venomous predators from the Indo-Pacific, are recent invaders of the Caribbean Basin and southeastern coast of North America. Quantification of invasive lionfish abundances, along with potentially important physical and biological environmental characteristics, permitted inferences about the invasion process of reefs on the island of San Salvador in the Bahamas. Environmental wave-exposure had a large influence on lionfish abundance, which was more than 20 and 120 times greater for density and biomass respectively at sheltered sites as compared with wave-exposed environments. Our measurements of topographic complexity of the reefs revealed that lionfish abundance was not driven by habitat rugosity. Lionfish abundance was not negatively affected by the abundance of large native predators (or large native groupers) and was also unrelated to the abundance of medium prey fishes (total length of 5-10 cm). These relationships suggest that (1) higher-energy environments may impose intrinsic resistance against lionfish invasion, (2) habitat complexity may not facilitate the lionfish invasion process, (3) predation or competition by native fishes may not provide biotic resistance against lionfish invasion, and (4) abundant prey fish might not facilitate lionfish invasion success. The relatively low biomass of large grouper on this island could explain our failure to detect suppression of lionfish abundance and we encourage continuing the preservation and restoration of potential lionfish predators in the Caribbean. In addition, energetic environments might exert direct or indirect resistance to the lionfish proliferation, providing native fish populations with essential refuges.
2012-07-27
Cambridge University Press. 47. Gritti ESB, Smith B, Sykes MT (2006) Vulnerability of Mediterranean Basin ecosystems to climate change and invasion by...2011) Monitoring diets and growth rates of native predatory fish stocked to suppress non-native tilapia. MS Thesis, Nicholls State University
Turbidity alters pre-mating social interactions between native and invasive stream fishes
Glotzbecker, Gregory J.; Ward, Jessica L.; Walters, David M.; Blum, Michael J.
2015-01-01
These findings suggest that elevated turbidity can increase pre-mating social interactions between native and invasive species, which could result in greater hybridisation and promote the genetic assimilation of native species following species introductions. Thus, integrating knowledge of species behaviour into conservation and management planning can help deter the establishment and spread of invasive species.
Responses of foothill yellow-legged frog (Rana boylii) larvae to an introduced predator
David J. Paoletti; Deanna H. Olson; Andrew R. Blaustein
2011-01-01
The consequences of species introductions into non-native habitats are a major cause for concern in the U.S. Of particular interest are the effects of predation by introduced fishes on native amphibian communities. We sought to determine whether Foothill Yellow-legged Frog (Rana boylii) larvae could recognize non-native Small mouth Bass (...
Kwan, Ye-Seul; Ko, Myeong-Hun; Won, Yong-Jin
2014-01-01
River connections via artificial canals will bring about secondary contacts between previously isolated fish species. Here, we present a genetic consequence of such a secondary contact between Cobitis fish species, C. lutheri in the Dongjin River, and C. tetralineata in the Seomjin River in Korea. The construction of water canals about 80 years ago has unidirectionally introduced C. tetralineata into the native habitat of C. lutheri, and then these species have hybridized in the main stream section of the Dongjin River. According to the divergence population genetic analyses of DNA sequence data, the two species diverged about 3.3 million years ago, which is interestingly coincident with the unprecedented paleoceanographic change that caused isolations of the paleo-river systems in northeast Asia due to sea-level changes around the late Pliocene. Multilocus genotypic data of nine microsatellites and three nuclear loci revealed an extensively admixed structure in the hybrid zone with a high proportion of various post-F1 hybrids. Surprisingly, pure native C. lutheri was absent in the hybrid zone in contrast to the 7% of pure C. tetralineata. Such a biased proportion must have resulted from the dominant influence of continually introducing C. tetralineata on the native C. lutheri which has no supply of natives from other tributaries to the hybrid zone due to numerous low-head dams. In addition, mating experiments indicated that there is no discernible reproductive isolation between them. All the results suggest that the gene pool of native C. lutheri is being rapidly replaced by that of continually introducing C. tetralineata through a hybrid swarm for the last 80 years, which will ultimately lead to the genomic extinction of natives in this hybrid zone. PMID:24834340
Schofield, Pamela J.; Loftus, William F.; Kobza, Robert M.; Cook, Mark I.; Slone, Daniel H.
2010-01-01
The cold tolerance of two non-native cichlids (Hemichromis letourneuxi and Cichlasoma urophthalmus) that are established in south Florida was tested in the field and laboratory. In the laboratory, fishes were acclimated to two temperatures (24 and 28°C), and three salinities (0, 10, and 35 ppt). Two endpoints were identified: loss of equilibrium (11.5–13.7°C for C. urophthalmus; 10.8–12.5°C for H. letourneuxi), and death (9.5–11.1°C for C. urophthalmus; 9.1–13.3°C for H. letourneuxi). In the field, fishes were caged in several aquatic habitats during two winter cold snaps. Temperatures were lowest (4.0°C) in the shallow marsh, where no fish survived, and warmest in canals and solution-holes. Canals and ditches as shallow as 50 cm provided thermal refuges for these tropical fishes. Because of the effect on survival of different habitat types, simple predictions of ultimate geographic expansion by non-native fishes using latitude and thermal isoclines are insufficient for freshwater fishes.
Parasites of ornamental fish commercialized in Macapá, Amapá State (Brazil).
Hoshino, Érico de Melo; Hoshino, Maria Danielle Figueiredo Guimarães; Tavares-Dias, Marcos
2018-02-19
This study investigated the parasites fauna of four freshwater ornamental fish species in aquarium shops of Macapá, Amapá State, in addition to survey the commercialized fish species and sanitary conditions of aquarium shops. Different native and non-native ornamental fish species were found in aquarium shops, mainly Poecilidae. We examined 30 specimens of Xiphophorus maculatus, 30 Danio rerio, 30 Paracheirodon axelrodi, and 30 Corydoras ephippifer for parasites. Of the 120 fish examined, 22.5% were parasitized by one or more species and a total of 438 parasites were collected and identified. Parasites such as: Ichthyophthirius multifiliis, Monogenea, undermined Digenea metacercariae, Acanthostomum sp. metacercariae, Camallanus spp., Bothriocephalus acheilognathi and Echinorhynchus sp. infected the hosts examined. Endoparasites in the larval stage showed the greatest diversity and Camallanus spp. was found in all hosts species examined. Paracheirodon axelrodi (43.3%) was the most parasitized host, while C. ephippifer (6.7%) was the least parasitized. Despite the low ectoparasites level, six species of endoparasites was observed, demonstrating that prophylactic and quarantine procedures were not fully adequate. Therefore, failures in prophylactic procedures on any link in the production industry of ornamental fish may cause parasite transmission to ornamental fish captured in different environments and localities.
Parasites of ornamental fish commercialized in Macapá, Amapá State (Brazil).
Hoshino, Érico de Melo; Hoshino, Maria Danielle Figueiredo Guimarães; Tavares-Dias, Marcos
2018-01-01
This study investigated the parasites fauna of four freshwater ornamental fish species in aquarium shops of Macapá, Amapá State, in addition to survey the commercialized fish species and sanitary conditions of aquarium shops. Different native and non-native ornamental fish species were found in aquarium shops, mainly Poecilidae. We examined 30 specimens of Xiphophorus maculatus, 30 Danio rerio, 30 Paracheirodon axelrodi, and 30 Corydoras ephippifer for parasites. Of the 120 fish examined, 22.5% were parasitized by one or more species and a total of 438 parasites were collected and identified. Parasites such as: Ichthyophthirius multifiliis, Monogenea, undermined Digenea metacercariae, Acanthostomum sp. metacercariae, Camallanus spp., Bothriocephalus acheilognathi and Echinorhynchus sp. infected the hosts examined. Endoparasites in the larval stage showed the greatest diversity and Camallanus spp. was found in all hosts species examined. Paracheirodon axelrodi (43.3%) was the most parasitized host, while C. ephippifer (6.7%) was the least parasitized. Despite the low ectoparasites level, six species of endoparasites was observed, demonstrating that prophylactic and quarantine procedures were not fully adequate. Therefore, failures in prophylactic procedures on any link in the production industry of ornamental fish may cause parasite transmission to ornamental fish captured in different environments and localities.
Locke, Sean A; Bulté, Grégory; Marcogliese, David J; Forbes, Mark R
2014-05-01
Populations of invasive species tend to have fewer parasites in their introduced ranges than in their native ranges and are also thought to have fewer parasites than native prey. This 'release' from parasites has unstudied implications for native predators feeding on exotic prey. In particular, shifts from native to exotic prey should reduce levels of trophically transmitted parasites. We tested this hypothesis in native populations of pumpkinseed sunfish (Lepomis gibbosus) in Lake Opinicon, where fish stomach contents were studied intensively in the 1970s, prior to the appearance of exotic zebra mussels (Dreissena polymorpha) in the mid-1990s. Zebra mussels were common in stomachs of present-day pumpkinseeds, and stable isotopes of carbon and nitrogen confirmed their importance in long-term diets. Because historical parasite data were not available in Lake Opinicon, we also surveyed stomach contents and parasites in pumpkinseed in both Lake Opinicon and an ecologically similar, neighboring lake where zebra mussels were absent. Stomach contents of pumpkinseed in the companion lake did not differ from those of pre-invasion fish from Lake Opinicon. The companion lake, therefore, served as a surrogate "pre-invasion" reference to assess effects of zebra mussel consumption on parasites in pumpkinseed. Trophically transmitted parasites were less species-rich and abundant in Lake Opinicon, where fish fed on zebra mussels, although factors other than zebra mussel consumption may contribute to these differences. Predation on zebra mussels has clearly contributed to a novel trophic coupling between littoral and pelagic food webs in Lake Opinicon.
RNA Imaging with Multiplexed Error Robust Fluorescence in situ Hybridization
Moffitt, Jeffrey R.; Zhuang, Xiaowei
2016-01-01
Quantitative measurements of both the copy number and spatial distribution of large fractions of the transcriptome in single-cells could revolutionize our understanding of a variety of cellular and tissue behaviors in both healthy and diseased states. Single-molecule Fluorescence In Situ Hybridization (smFISH)—an approach where individual RNAs are labeled with fluorescent probes and imaged in their native cellular and tissue context—provides both the copy number and spatial context of RNAs but has been limited in the number of RNA species that can be measured simultaneously. Here we describe Multiplexed Error Robust Fluorescence In Situ Hybridization (MERFISH), a massively parallelized form of smFISH that can image and identify hundreds to thousands of different RNA species simultaneously with high accuracy in individual cells in their native spatial context. We provide detailed protocols on all aspects of MERFISH, including probe design, data collection, and data analysis to allow interested laboratories to perform MERFISH measurements themselves. PMID:27241748
Estimating the rate of biological introductions: Lessepsian fishes in the Mediterranean.
Belmaker, Jonathan; Brokovich, Eran; China, Victor; Golani, Daniel; Kiflawi, Moshe
2009-04-01
Sampling issues preclude the direct use of the discovery rate of exotic species as a robust estimate of their rate of introduction. Recently, a method was advanced that allows maximum-likelihood estimation of both the observational probability and the introduction rate from the discovery record. Here, we propose an alternative approach that utilizes the discovery record of native species to control for sampling effort. Implemented in a Bayesian framework using Markov chain Monte Carlo simulations, the approach provides estimates of the rate of introduction of the exotic species, and of additional parameters such as the size of the species pool from which they are drawn. We illustrate the approach using Red Sea fishes recorded in the eastern Mediterranean, after crossing the Suez Canal, and show that the two approaches may lead to different conclusions. The analytical framework is highly flexible and could provide a basis for easy modification to other systems for which first-sighting data on native and introduced species are available.
Byron, Meg; Hall, Lisa L; Lawrence, Jeanne B
2013-01-01
Fluorescence in situ hybridization (FISH) is not a singular technique, but a battery of powerful and versatile tools for examining the distribution of endogenous genes and RNAs in precise context with each other and in relation to specific proteins or cell structures. This unit offers the details of highly sensitive and successful protocols that were initially developed largely in our lab and honed over a number of years. Our emphasis is on analysis of nuclear RNAs and DNA to address specific biological questions about nuclear structure, pre-mRNA metabolism, or the role of noncoding RNAs; however, cytoplasmic RNA detection is also discussed. Multifaceted molecular cytological approaches bring precise resolution and sensitive multicolor detection to illuminate the organization and functional roles of endogenous genes and their RNAs within the native structure of fixed cells. Solutions to several common technical pitfalls are discussed, as are cautions regarding the judicious use of digital imaging and the rigors of analyzing and interpreting complex molecular cytological results.
Climate change poised to threaten hydrologic connectivity and endemic fishes in dryland streams
Jaeger, Kristin L.; Olden, Julian D.; Pelland, Noel A.
2014-01-01
Protecting hydrologic connectivity of freshwater ecosystems is fundamental to ensuring species persistence, ecosystem integrity, and human well-being. More frequent and severe droughts associated with climate change are poised to significantly alter flow intermittence patterns and hydrologic connectivity in dryland streams of the American Southwest, with deleterious effects on highly endangered fishes. By integrating local-scale hydrologic modeling with emerging approaches in landscape ecology, we quantify fine-resolution, watershed-scale changes in habitat size, spacing, and connectance under forecasted climate change in the Verde River Basin, United States. Model simulations project annual zero-flow day frequency to increase by 27% by midcentury, with differential seasonal consequences on continuity (temporal continuity at discrete locations) and connectivity (spatial continuity within the network). A 17% increase in the frequency of stream drying events is expected throughout the network with associated increases in the duration of these events. Flowing portions of the river network will diminish between 8% and 20% in spring and early summer and become increasingly isolated by more frequent and longer stretches of dry channel fragments, thus limiting the opportunity for native fishes to access spawning habitats and seasonally available refuges. Model predictions suggest that midcentury and late century climate will reduce network-wide hydrologic connectivity for native fishes by 6–9% over the course of a year and up to 12–18% during spring spawning months. Our work quantifies climate-induced shifts in stream drying and connectivity across a large river network and demonstrates their implications for the persistence of a globally endemic fish fauna. PMID:25136090
Mitigation for the Construction and Operation of Libby Dam, 2003-2004 Annual Report.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dunnigan, James; DeShazer, Jay; Garrow, Larry
2004-06-01
''Mitigation for the Construction and Operation of Libby Dam'' is part of the Northwest Power and Conservation Council's (NPCC) resident fish and wildlife program. The program was mandated by the Northwest Planning Act of 1980, and is responsible for mitigating for damages to fish and wildlife caused by hydroelectric development in the Columbia River Basin. The objective of Phase I of the project (1983 through 1987) was to maintain or enhance the Libby Reservoir fishery by quantifying seasonal water levels and developing ecologically sound operational guidelines. The objective of Phase II of the project (1988 through 1996) was to determinemore » the biological effects of reservoir operations combined with biotic changes associated with an aging reservoir. The objectives of Phase III of the project (1996 through present) are to implement habitat enhancement measures to mitigate for dam effects, to provide data for implementation of operational strategies that benefit resident fish, monitor reservoir and river conditions, and monitor mitigation projects for effectiveness. This project completes urgent and high priority mitigation actions as directed by the Kootenai Subbasin Plan. Montana FWP uses a combination of diverse techniques to collect a variety of physical and biological data within the Kootenai River Basin. These data serve several purposes including: the development and refinement of models used in management of water resources and operation of Libby Dam; investigations into the limiting factors of native fish populations, gathering basic life history information, tracking trends in endangered, threatened species, and the assessment of restoration or management activities intended to restore native fishes and their habitats.« less
Climate change poised to threaten hydrologic connectivity and endemic fishes in dryland streams.
Jaeger, Kristin L; Olden, Julian D; Pelland, Noel A
2014-09-23
Protecting hydrologic connectivity of freshwater ecosystems is fundamental to ensuring species persistence, ecosystem integrity, and human well-being. More frequent and severe droughts associated with climate change are poised to significantly alter flow intermittence patterns and hydrologic connectivity in dryland streams of the American Southwest, with deleterious effects on highly endangered fishes. By integrating local-scale hydrologic modeling with emerging approaches in landscape ecology, we quantify fine-resolution, watershed-scale changes in habitat size, spacing, and connectance under forecasted climate change in the Verde River Basin, United States. Model simulations project annual zero-flow day frequency to increase by 27% by midcentury, with differential seasonal consequences on continuity (temporal continuity at discrete locations) and connectivity (spatial continuity within the network). A 17% increase in the frequency of stream drying events is expected throughout the network with associated increases in the duration of these events. Flowing portions of the river network will diminish between 8% and 20% in spring and early summer and become increasingly isolated by more frequent and longer stretches of dry channel fragments, thus limiting the opportunity for native fishes to access spawning habitats and seasonally available refuges. Model predictions suggest that midcentury and late century climate will reduce network-wide hydrologic connectivity for native fishes by 6-9% over the course of a year and up to 12-18% during spring spawning months. Our work quantifies climate-induced shifts in stream drying and connectivity across a large river network and demonstrates their implications for the persistence of a globally endemic fish fauna.
25 CFR 243.7 - How can a non-Native acquire live reindeer?
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 1 2010-04-01 2010-04-01 false How can a non-Native acquire live reindeer? 243.7 Section 243.7 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE REINDEER IN ALASKA § 243.7 How can a non-Native acquire live reindeer? If you are a non-Native who wants to acquire live Alaskan reindeer, you must apply to us in...
Diamond, J M; Serveiss, V B
2001-12-15
The free-flowing Clinch and Powell River Basin, located in southwestern Virginia, United States, historically had one of the richest assemblages of native fish and freshwater mussels in the world. Nearly half of the species once residing here are now extinct, threatened, or endangered. The United States Environmental Protection Agency's framework for conducting an ecological risk assessment was used to structure a watershed-scale analysis of human land use, in-stream habitat quality, and their relationship to native fish and mussel populations in order to develop future management strategies and prioritize areas in need of enhanced protection. Our analyses indicate that agricultural and urban land uses as well as proximity to mining activities and transportation corridors are inversely related to fish index of biotic integrity (IBI) and mussel species diversity. Forward stepwise multiple regression analyses indicated that coal mining had the most impact on fish IBI followed by percent cropland and urban area in the riparian corridor (R2 = 0.55, p = 0.02); however, these analyses suggest that other site-specific factors are important. Habitat quality measures accounted for as much as approximately half of the variability in fish IBI values if the analysis was limited to sites within a relatively narrow elevation range. These results, in addition to other data collected in this watershed, suggest that nonhabitat-related stressors (e.g., accidental chemical spills) also have significant effects on biota in this basin. The number of co-occurring human land uses was inversely related to fish IBI (r = -0.49, p < 0.01). Sites with > or = 2 co-occurring land uses had >90% probability of having <2 mussel species present. Our findings predict that many mussel concentration sites are vulnerable to future extirpation. In addition, our results suggest that protection and enhancement of naturally vegetated riparian corridors, better controls of mine effluents and urban runoff, and increased safeguards against accidental chemical spills, as well as reintroduction or augmentation of threatened and endangered species, may help sustain native fish and mussel populations in this watershed.
Barko, V.A.; Herzog, D.P.; O'Connell, M. T.
2006-01-01
We examined data collected on fish assemblage structure among three differing floodplain types (broad, moderate, and narrow) during the 1993 flood in the unimpounded reach of the upper Mississippi River. This 500 year flood event provided a unique opportunity to investigate fish-floodplain function because the main river channel is otherwise typically disjunct from approximately 82% of its floodplain by an extensive levee system. Fishes were sampled during three separate periods, and 42 species of adult and young-of-the-year (YOY) fishes were captured. Analysis of similarity (ANOSIM) revealed a significant and distinguishable difference between both adult and YOY assemblage structure among the three floodplain types. Analysis of variance revealed that Secchi transparency, turbidity, water velocity, and dissolved oxygen were significantly different among the floodplain types. However, only depth of gear deployment and Secchi transparency were significantly correlated with adult assemblage structure. None of these variables were significantly correlated with YOY assemblage structure. The numerically abundant families (adult and YOY catches combined) on the floodplain included Centrarchidae, Ictularidae, and Cyprinidae. Both native and non-native fishes were captured on the floodplain, and several of the numerically abundant species that were captured on the floodplain peaked in catch-per-unit-effort 1-3 years after the 1993 flood event. This suggests that some species may have used flooded terrestrial habitat for spawning, feeding, or both. The findings from our study provide much needed insight into fish-floodplain function in a temperate, channelized river system and suggest that lateral connectivity of the main river channel to less degraded reaches of its floodplain should become a management priority not only to maintain faunal biodiversity but also potentially reduce the impacts of non-native species in large river systems.
Senecal, Anna C.; Walters, Annika W.; Hubert, Wayne A.
2016-01-01
Wyoming’s Powder River is considered an example of a pristine prairie river system. While the river hosts a largely native fish assemblage and remains unimpounded over its 1,146-km course to the Yellowstone River confluence, the hydrologic regime has been altered through water diversion for agriculture and natural gas extraction and there has been limited study of fish assemblage structure. We analyzed fish data collected from the mainstem Powder River in Wyoming between 1896 and 2008. Shifts in presence/absence and relative abundance of fish species, as well as fish assemblage composition, were assessed among historical and recent samples. The recent Powder River fish assemblage was characterized by increased relative abundances of sand shiner Notropis stramineus and plains killifish Fundulus zebrinus, and decreases in sturgeon chub Macrhybopsis gelida. Shifts in fish species relative abundance are linked to their reproductive ecology with species with adhesive eggs generally increasing in relative abundance while those with buoyant drifting eggs are decreasing. Assemblage shifts could be the result of landscape level changes, such as the loss of extreme high and low flow events and changing land use practices.
Vajda, Alan M.; Kumar, Anupama; Woods, Marianne; Williams, Mike; Doan, Hai; Tolsher, Peter; Kookana, Rai S.; Barber, Larry B.
2016-01-01
The contamination of major continental river systems by endocrine-active chemicals (EACs) derived from the discharge of wastewater treatment plant (WWTP) effluents can affect human and ecosystem health. As part of a long-term effort to develop a native fish model organism for assessment of endocrine disruption in Australia's largest watershed, the Murray-Darling River Basin, the present study evaluated endocrine disruption in adult males of the native Australian Murray rainbowfish (Melanotaenia fluviatilis) exposed to effluent from an activated sludge WWTP and water from the Murray River during a 28-d, continuous-flow, on-site experiment. Analysis of the WWTP effluent and river water detected estrone and 17β-estradiol at concentrations up to approximately 25 ng L−1. Anti-estrogenicity of effluent samples was detected in vitro using yeast-based bioassays (yeast estrogen screen) throughout the experiment, but estrogenicity was limited to the first week of the experiment. Histological evaluation of the testes indicated significant suppression of spermatogenesis by WWTP effluent after 28 d of exposure. Plasma vitellogenin concentrations and expression of vitellogenin messenger RNA in liver were not significantly affected by exposure to WWTP effluent. The combination of low contaminant concentrations in the WWTP effluent, limited endocrine disrupting effects in the Murray rainbowfish, and high in-stream dilution factors (>99%) suggest minimal endocrine disruption impacts on native Australian fish in the Murray River downstream from the WWTP outfall.
Smith, Shannen M; Fox, Rebecca J; Booth, David J; Donelson, Jennifer M
2018-04-01
Range shifts of tropical marine species to temperate latitudes are predicted to increase as a consequence of climate change. To date, the research focus on climate-mediated range shifts has been predominately dealt with the physiological capacity of tropical species to cope with the thermal challenges imposed by temperate latitudes. Behavioural traits of individuals in the novel temperate environment have not previously been investigated, however, they are also likely to play a key role in determining the establishment success of individual species at the range-expansion forefront. The aim of this study was to investigate the effect of shoaling strategy on the performance of juvenile tropical reef fishes that recruit annually to temperate waters off the south east coast of Australia. Specifically, we compared body-size distributions and the seasonal decline in abundance through time of juvenile tropical fishes that shoaled with native temperate species ('mixed' shoals) to those that shoaled only with conspecifics (as would be the case in their tropical range). We found that shoaling with temperate native species benefitted juvenile tropical reef fishes, with individuals in 'mixed' shoals attaining larger body-sizes over the season than those in 'tropical-only' shoals. This benefit in terms of population body-size distributions was accompanied by greater social cohesion of 'mixed' shoals across the season. Our results highlight the impact that sociality and behavioural plasticity are likely to play in determining the impact on native fish communities of climate-induced range expansion of coral reef fishes. © 2018 John Wiley & Sons Ltd.
Coral reef grazer-benthos dynamics complicated by invasive algae in a small marine reserve
Stamoulis, Kostantinos A.; Friedlander, Alan M.; Meyer, Carl G.; Fernandez-Silva, Iria; Toonen, Robert J.
2017-01-01
Blooms of alien invasive marine algae have become common, greatly altering the health and stability of nearshore marine ecosystems. Concurrently, herbivorous fishes have been severely overfished in many locations worldwide, contributing to increases in macroalgal cover. We used a multi-pronged, interdisciplinary approach to test if higher biomass of herbivorous fishes inside a no-take marine reserve makes this area more resistant to invasive algal overgrowth. Over a two year time period, we (1) compared fish biomass and algal cover between two fished and one unfished patch reef in Hawai’i, (2) used acoustic telemetry to determine fidelity of herbivorous fishes to the unfished reef, and (3) used metabarcoding and next-generation sequencing to determine diet composition of herbivorous fishes. Herbivore fish biomass was significantly higher in the marine reserve compared to adjacent fished reefs, whereas invasive algal cover differed by species. Herbivorous fish movements were largely confined to the unfished patch reef where they were captured. Diet analysis indicated that the consumption of invasive algae varied among fish species, with a high prevalence of comparatively rare native algal species. Together these findings demonstrate that the contribution of herbivores to coral reef resilience, via resistance to invasive algae invasion, is complex and species-specific. PMID:28276458
Native montane fishes of the Middle Rio Grande Ecosystem: Status, threats, and conservation
Bob Calamusso; John N. Rinne
1999-01-01
Between 1994 and 1997, research was conducted on three native, montane species of the Middle Rio Grande Ecosystem, in the Carson and Santa Fe national forests. The focus of study was on abiotic and biotic factors that affected status, distribution, biology and habitat of these species. Results of study suggest negative interactions with non-native species and,...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-21
...-management process involving the Service, the Alaska Department of Fish and Game, and Alaska Native... developed under a co-management process involving the Service, the Alaska Department of Fish and Game, and... Fish and Game's request to expand the Fairbanks North Star Borough excluded area to include the Central...
Wang, Xiao-Nan; Liu, Zheng-Tao; Yan, Zhen-Guang; Zhang, Cong; Wang, Wei-Li; Zhou, Jun-Li; Pei, Shu-Wei
2013-09-15
Triclosan (TCS) is an antimicrobial agent which is used as a broad-spectrum bacteriostatic and found in personal care products, and due to this it is widely spread in the aquatic environment. However, there is no paper dealing with the aquatic life criteria of TCS, mainly result from the shortage of toxicity data of different taxonomic levels. In the present study, toxicity data were obtained from 9 acute toxicity tests and 3 chronic toxicity tests using 9 Chinese native aquatic species from different taxonomic levels, and the aquatic life criteria was derived using 3 methods. Furthermore, differences of species sensitivity distributions (SSD) between native and non-native species were compared. Among the tested species, demersal fish Misgurnus anguillicaudatus was the most sensitive species, and the fishes were more sensitive than the aquatic invertebrates of Annelid and insect, and the insect was the least sensitive species. The comparison showed that there was no significant difference between SSDs constructed from native and non-native taxa. Finally, a criterion maximum concentration of 0.009 mg/L and a criterion continuous concentration of 0.002 mg/L were developed based on different taxa, according to the U.S. Environmental Protection Agency guidelines. Copyright © 2013 Elsevier B.V. All rights reserved.
Ecohydrological Index, Native Fish, and Climate Trends and Relationships in the Kansas River Basin.
Sinnathamby, Sumathy; Douglas-Mankin, Kyle R; Muche, Muluken E; Hutchinson, Stacy L; Anandhi, Aavudai
2018-01-01
This study quantified climatological and hydrological trends and relationships to presence and distribution of two native aquatic species in the Kansas River Basin over the past half-century. Trend analyses were applied to indicators of hydrologic alteration (IHAs) at 34 streamgages over a 50-year period (1962-2012). Results showed a significant negative trend in annual streamflow for 10 of 12 western streamgages (up to -7.65 mm/50 yr) and smaller negative trends for most other streamgages. Significant negative trends in western Basin streamflow were more widespread in summer (12 stations) than winter or spring (6 stations). The negative-trend magnitude and significance decreased from west to east for maximum-flow IHAs. Minimum- flow IHAs, however, significantly decreased at High Plains streamgages but significantly increased at Central Great Plains streamgages. Number of zero-flow days showed positive trends in the High Plains. Most streamgages showed negative trends in low- and high-flow pulse frequency and high-flow pulse duration, and positive trends in low-flow pulse duration. These results were consistent with increasing occurrence of drought. Shift in occurrence from present (1860-1950) to absent (2000-2012) was significantly related (p<0.10) to negative trends of 1-day maximum flows (both species) and indices associated with reduced spawning-season flows for Plains Minnow and shifting annual-flow timing and increased flow intermittency for Common Shiner. Both species were absent for all western Basin sites and had different responses to hydrological index trends at eastern Basin sites. These results demonstrate ecohydrological index changes impact distributions of native fish and suggest target factors for assessment or restoration activities.
Thermal controls of Yellowstone cutthroat trout and invasive fishes under climate change
Al-Chokhachy, Robert K.; Alder, Jay R.; Hostetler, Steven W.; Gresswell, Robert E.; Shepard, Bradley
2013-01-01
We combine large observed data sets and dynamically downscaled climate data to explore historic and future (2050–2069) stream temperature changes over the topographically diverse Greater Yellowstone Ecosystem (elevation range = 824–4017 m). We link future stream temperatures with fish growth models to investigate how changing thermal regimes could influence the future distribution and persistence of native Yellowstone cutthroat trout (YCT) and competing invasive species. We find that stream temperatures during the recent decade (2000–2009) surpass the anomalously warm period of the 1930s. Climate simulations indicate air temperatures will warm by 1 °C to >3 °C over the Greater Yellowstone by mid-21st century, resulting in concomitant increases in 2050–2069 peak stream temperatures and protracted periods of warming from May to September (MJJAS). Projected changes in thermal regimes during the MJJAS growing season modify the trajectories of daily growth rates at all elevations with pronounced growth during early and late summer. For high-elevation populations, we find considerable increases in fish body mass attributable both to warming of cold-water temperatures and to extended growing seasons. During peak July to August warming, mid-21st century temperatures will cause periods of increased thermal stress, rendering some low-elevation streams less suitable for YCT. The majority (80%) of sites currently inhabited by YCT, however, display minimal loss (<10%) or positive changes in total body mass by midcentury; we attribute this response to the fact that many low-elevation populations of YCT have already been extirpated by historical changes in land use and invasions of non-native species. Our results further suggest that benefits to YCT populations due to warmer stream temperatures at currently cold sites could be offset by the interspecific effects of corresponding growth of sympatric, non-native species, underscoring the importance of developing climate adaptation strategies that reduce limiting factors such as non-native species and habitat degradation.
Hartman, Rosemary; Pope, Karen; Lawler, Sharon
2014-06-01
Habitat characteristics mediate predator-prey coexistence in many ecological systems but are seldom considered in species introductions. When economically important introduced predators are stocked despite known negative impacts on native species, understanding the role of refuges, landscape configurations, and community interactions can inform habitat management plans. We measured these factors in basins with introduced trout (Salmonidae) and the Cascades frog (Rana cascadae) to determine, which are responsible for observed patterns of co-occurrence of this economically important predator and its native prey. Large, vegetated shallows were strongly correlated to co-occurrence, and R. cascadae larvae occur in shallower water when fish are present, presumably to escape predation. The number of nearby breeding sites of R. cascadae was also correlated to co-occurrence, but only when the western toad (Anaxyrus boreas) was present. Because A. boreas larvae are unpalatable to fish and resemble R. cascadae, they may provide protection from trout via Batesian mimicry. Although rescue-effect dispersal from nearby populations may maintain co-occurrence, within-lake factors proved more important for predicting co-occurrence. Learning which factors allow co-occurrence between economically important introduced species and their native prey enables managers to make better-informed stocking decisions. © 2013 Society for Conservation Biology.
Pearl, Christopher A.; Adams, Michael J.; Schuytema, Gerald S.; Nebeker, A.V.
2003-01-01
We compared behavioral responses of larvae of three Pacific Northwest anurans from different hydroperiods to water borne cues of native and introduced predators. Two native anurans (Pacific Treefrog, Pseudacris regilla, and Northern Red-Legged Frog, Rana aurora aurora) and introduced Bullfrogs (Rana catesbeiana) responded to water conditioned by native Redside Shiners (Richardsonius balteatus) by increasing refuge use. The larvae of the two native anurans differed in their response to introduced predator cues. Rana aurora aurora, which occur in temporary and permanent waters, responded to both introduced Bluegill Sunfish (Lepomis macrochirus) and introduced Crayfish (Procambarus clarkii). Pseudacris regilla, which occur primarily in temporary ponds, did not respond to water borne cues from either introduced predator. The broader responses of R. a. aurora may indicate greater behavioral plasticity or more exposure to novel predators than experienced by P. regilla. Larvae of introduced R. catesbeiana responded strongly to cues from two fish native to the Pacific northwest but did not alter behavior in response to any of five potential predators with which they coexist in their native range. Fish that occur with R. catesbeiana in their native range generally find Bullfrog larvae unpalatable. This pattern suggests that Bullfrog larvae can recognize cues of novel predators that may find them palatable, which could contribute to their success as an invasive species in the region.
Atrazine reduces reproduction in fathead minnow (Pimephales promelas): raw data report
Tillitt, Donald E.; Papoulias, Diana M.; Whyte, Jeffrey J.; Richter, Catherine A.
2014-01-01
The herbicide, atrazine, routinely is observed in surface and groundwaters, particularly in the “corn belt” region, a high-use area of the United States. Atrazine has demonstrated effects on reproduction in mammals and amphibians, but the characterization of endocrine-related effects in fish has received only limited attention. Peak concentrations of atrazine in surface water of streams from these agricultural areas coincide with annual spawning events of native fishes. Consequently, there was an unacceptable level of uncertainty in our understanding of the risks associated with the periods of greatest atrazine exposure and greatest vulnerability of certain species of fishes. For this reason, a study of the effects of atrazine on fathead minnow reproduction was undertaken (Tillitt and others, 2010). This report provides the raw data from that study.
Hurst, Timothy P; Brown, Michael D; Kay, Brian H
2004-09-01
The introduction and establishment of fish populations can provide long-term, cost-effective mosquito control in habitats such as constructed wetlands and ornamental lakes. The predation efficacy of 7 native Brisbane freshwater fish on 1st and 4th instars of the freshwater arbovirus vector Culex annulirostris was evaluated in a series of 24-h laboratory trials. The trials were conducted in 30-liter plastic carboys at 25+/-1 degrees C under a light:dark cycle of 14:10 h. The predation efficacy of native crimson-spotted rainbowfish Melanotaenia duboulayi (Melanotaeniidae), Australian smelt Retropinna semoni (Retropinnadae), Pacific blue-eye Pseudomugil signifer (Atherinidae), fly-specked hardyhead Craterocephalus stercusmuscarum (Atherinidae), firetail gudgeon Hypseleotris galii (Eleotridae), empire gudgeon Hypseleotris compressa (Eleotridae), and estuary perchlet Ambassis marianus (Ambassidae) was compared with the exotic eastern mosquitofish Gambusia holbrooki (Poeciliidae). This environmentally damaging exotic has been disseminated worldwide and has been declared noxious in Queensland. Melanotaenia duboulayi was found to consume the greatest numbers of both 1st and 4th instars of Cx. annulirostris. The predation efficacy of the remaining Australian native species was comparable with that of the exotic G. holbrooki. With the exception of A. marianus, the maximum predation rates of these native species were not statistically different whether tested individually or in a school of 6. Based on these data, M. duboulayi, H. compressa, and A. marianus warrant further investigation as biological control agents in pilot field trials.
Wildlife habitats in managed rangelands—the Great Basin of southeastern Oregon: native trout.
Wayne Bowers; Bill Hosford; Art Oakley; Carl. Bond
1979-01-01
Southeastern Oregon has a variety of fish habitats which include major rivers, tributary streams, large and small reservoirs, lakes, and springs. These habitats are directly related to and highly dependent on the conditions of the surrounding rangeland watersheds. Satterlund (1975, p. 22) put it this way: "Rangelands may yield little water, but they are second...
Creative Photography - Wildlife
2016-03-25
From its perch high up in a pine tree at Merritt Island National Wildlife Refuge in Florida, a bald eagle keeps a watchful eye on its large nest, called an aerie. NASA’s Kennedy Space Center shares boundaries with the refuge, which is home to more than 330 native and migratory bird species, along with 25 mammal, 117 fish, and 65 amphibian and reptile species.
Neville, Helen M.; Dunham, Jason B.
2011-01-01
Hybridization is one of the greatest threats to native fishes. Threats from hybridization are particularly important for native trout species as stocking of nonnative trout has been widespread within the ranges of native species, thus increasing the potential for hybridization. While many studies have documented hybridization between native cutthroat trout Oncorhynchus clarkii and nonnative rainbow trout O. mykiss, fewer have focused on this issue in native rainbow trout despite widespread threats from introductions of both nonnative cutthroat trout and hatchery rainbow trout. Here, we describe the current genetic (i.e., hybridization) status of native redband trout O. mykiss gairdneri populations in the upper Boise River, Idaho. Interspecific hybridization was widespread (detected at 14 of the 41 sampled locations), but high levels of hybridization between nonnative cutthroat trout and redband trout were detected in only a few streams. Intraspecific hybridization was considerably more widespread (almost 40% of sampled locations), and several local populations of native redband trout have been almost completely replaced with hatchery coastal rainbow trout O. mykiss irideus; other populations exist as hybrid swarms, some are in the process of being actively invaded, and some are maintaining genetic characteristics of native populations. The persistence of some redband trout populations with high genetic integrity provides some opportunity to conserve native genomes, but our findings also highlight the complex decisions facing managers today. Effective management strategies in this system may include analysis of the specific attributes of each site and population to evaluate the relative risks posed by isolation versus maintaining connectivity, identifying potential sites for control or eradication of nonnative trout, and long-term monitoring of the genetic integrity of remaining redband trout populations to track changes in their status.
Ferrari, Stephen F.; Vasconcelos, Huann C. G.; Mendes-Junior, Raimundo N. G.; Araújo, Andrea S.; Costa-Campos, Carlos Eduardo; Nascimento, Walace S.; Isaac, Victoria J.
2016-01-01
Urbanization causes environmental impacts that threaten the health of aquatic communities and alter their recovery patterns. In this study, we evaluated the diversity of intertidal fish in six areas affected by urbanization (areas with native vegetation, deforested areas, and areas in process of restoration of vegetation) along an urban waterfront in the Amazon River. 20 species were identified, representing 17 genera, 14 families, and 8 orders. The different degrees of habitat degradation had a major effect on the composition of the fish fauna; the two least affected sectors were the only ones in that all 20 species were found. Eight species were recorded in the most degraded areas. The analysis revealed two well-defined groups, coinciding with the sectors in better ecological quality and degraded areas, respectively. The native vegetation has been identified as the crucial factor to the recovery and homeostasis of the studied ecosystem, justifying its legal protection and its use in the restoration and conservation of altered and threatened environments. These results reinforce the importance of maintaining the native vegetation as well as its restoration in order to benefit of the fish populations in intertidal zones impacted by alterations resulting from inadequate urbanization. PMID:27699201
Eradication of invasive Tamarix ramosissima along a desert stream increases native fish density
Kennedy, T.A.; Finlay, J.C.; Hobbie, S.E.
2005-01-01
Spring ecosystems of the western United States have high conservation value, particularly because of the highly endemic, and often endangered, fauna that they support. Refuges now protect these habitats from many of the human impacts that once threatened them, but invasive species often persist. Invasive saltcedar is ubiquitous along streams, rivers, and spring ecosystems of the western United States, yet the impact of saltcedar invasion on these ecosystems, or ecosystem response to its removal, have rarely been quantified. Along Jackrabbit Spring, a springbrook in Nevada that supports populations of two endangered fish (Ash Meadows pupfish and Ash Meadows speckled dace) as well as several exotic aquatic consumers, we quantified the response of aquatic consumers to largescale saltcedar removal and identified the mechanism underlying consumer response to the removal. Clearing saltcedar from the riparian zone increased densities of native pupfish and exotic screw snails, but decreased the density of exotic crayfish. Positive effects of saltcedar removal on pupfish and snails occurred because saltcedar heavily shades the stream, greatly reducing the availability of algae for herbivores. This was confirmed by analyses of potential organic matter sources and consumer 13C: pupfish and snails, along with native dace and exotic mosquitofish, relied heavily on algae-derived carbon and not saltcedar-derived carbon. By contrast, crayfish ??13C values mirrored algae ??13C during summer, but in winter indicated reliance on allochthonous saltcedar litter that dominated organic inputs in saltcedar reaches and on algae-derived carbon where saltcedar was absent. The seasonal use of saltcedar by crayfish likely explains its negative response to saltcedar removal. Clearing saltcedar effectively restored the springbrook of Jackrabbit Spring to the conditions characteristic of native vegetation sites. Given the high conservation value of spring ecosystems and the potential conservation benefits of saltcedar removal that this research highlights, eradicating saltcedar from spring ecosystems of the western United States should clearly be a management priority. ?? 2005 by the Ecological Society of America.
Oki, Delwyn S.; Brasher, Anne M.D.
2003-01-01
The island of Oahu is the third largest island of the State of Hawaii, and is formed by the eroded remnants of the Waianae and Koolau shield volcanoes. The landscape of Oahu ranges from a broad coastal plain to steep interior mountains. Rainfall is greatest in the mountainous interior parts of the island, and lowest near the southwestern coastal areas. The structure and form of the two volcanoes in conjunction with processes that have modified the original surfaces of the volcanoes control the hydrologic setting. The rift zones of the volcanoes contain dikes that tend to impede the flow of ground water, leading to high ground-water levels in the dike-impounded ground-water system. In the windward (northeastern) part of the island, dike-impounded ground-water levels may reach the land surface in stream valleys, resulting in ground-water discharge to streams. Where dikes are not present, the volcanic rocks are highly permeable, and a lens of freshwater overlies a brackish-water transition zone separating the freshwater from saltwater. Ground water discharges to coastal springs and streams where the water table in the freshwater-lens system intersects the land surface. The Waianae and Koolau Ranges have been deeply dissected by numerous streams. Streams originate in the mountainous interior areas and terminate at the coast. Some streams flow perennially throughout their entire course, others flow perennially over parts of their course, and the remaining streams flow during only parts of the year throughout their entire course. Hawaiian streams have relatively few native species compared to continental streams. Widespread diverse orders of insects are absent from the native biota, and there are only five native fish, two native shrimp, and a few native snails. The native fish and crustaceans of Hawaii's freshwater systems are all amphidromous (adult lives are spent in streams, and larval periods as marine or estuarine zooplankton). During the 20th century, land-use patterns on Oahu reflected increases in population and decreases in large-scale agricultural operations over time. The last two remaining sugarcane plantations on Oahu closed in the mid-1990's, and much of the land that once was used for sugarcane now is urbanized or used for diversified agriculture. Although two large pineapple plantations continue to operate in central Oahu, some of the land previously used for pineapple cultivation has been urbanized. Natural and human-related factors control surface- and ground-water quality and the distribution and abundance of aquatic biota on Oahu. Natural factors that may affect water quality include geology, soils, vegetation, rainfall, ocean-water quality, and air quality. Human-related factors associated with urban and agricultural land uses also may affect water quality. Ground-water withdrawals may cause saltwater intrusion. Pesticides and fertilizers that were used in agricultural or urban areas have been detected in surface and ground water on Oahu. In addition, other organic compounds associated with urban uses of chemicals have been detected in surface and ground water on Oahu. The effects of urbanization and agricultural practices on instream and riparian areas in conjunction with a proliferation of nonnative fish and crustaceans have resulted in a paucity of native freshwater macrofauna on Oahu. A variety of pesticides, nutrients, and metals are associated with urban and agricultural land uses, and these constituents can affect the fish and invertebrates that live in the streams.
ERIC Educational Resources Information Center
Needham, Scott
A guide, in French, to raising fish for food and profit is designed to instruct and encourage Gabonese natives to establish family fisheries. It describes and illustrates in story form the process used to plan the fishery, clear the land, seek help from an agricultural agent, create a dam, make compost, plan and build the pond, feed the fish,…
Olivatti, A M; Boni, T A; Silva-Júnior, N J; Resende, L V; Gouveia, F O; Telles, M P C
2011-01-01
Leporinus friderici, native to the Amazon Basin and popularly known as "piau-três-pintas", has great ecological and economic importance; it is widely fished and consumed throughout much of tropical South America. Knowledge of the genetic diversity of this native species is important to support management and conservation programs. We evaluated microsatellite loci amplification, using heterologous primers, in 31 individuals of L. friderici. These samples were collected from natural populations of the Araguaia River basin, in central Brazil, and the DNA was extracted from samples of muscle tissue. Eight loci were successfully analyzed. Six of them were polymorphic, and the number of alleles ranged from three to 10. Values of expected heterozygosities for these polymorphic loci ranged from 0.488 to 0.795. Exclusion probability (0.983), the identity probability (0.000073), and the mean genetic diversity values were high, showing that these microsatellite markers are suitable for assessing the genetic variability of L. friderici populations. There is a growing interest in studies that evaluate the genetic variability of natural populations for various purposes, such as conservation. Here, we showed that a viable alternative to the costly development of specific primers for fish populations is simply testing for heterologous amplification of microsatellite markers available from research on other species.
Midway, Stephen R.; Wagner, Tyler; Tracy, Bryn H.; Hogue, Gabriela M.; Starnes, Wayne C.
2015-01-01
Worldwide, streams and rivers are facing a suite of pressures that alter water quality and degrade physical habitat, both of which can lead to changes in the composition and richness of fish populations. These potential changes are of particular importance in the Southeast USA, home to one of the richest stream fish assemblages in North America. Using data from 83 stream sites in North Carolina sampled in the 1960’s and the past decade, we used hierarchical Bayesian models to evaluate relationships between species richness and catchment land use and land cover (e.g., agriculture and forest cover). In addition, we examined how the rate of change in species richness over 50 years was related to catchment land use and land cover. We found a negative and positive correlation between forest land cover and agricultural land use and average species richness, respectively. After controlling for introduced species, most (66 %) stream sites showed an increase in native fish species richness, and the magnitude of the rate of increase was positively correlated to the amount of forested land cover in the catchment. Site-specific trends in species richness were not positive, on average, until the percentage forest cover in the network catchment exceeded about 55 %. These results suggest that streams with catchments that have moderate to high (>55 %) levels of forested land in upstream network catchments may be better able to increase the number of native species at a faster rate compared to less-forested catchments.
An ecological basis for future fish habitat restoration efforts in the Huron-Erie Corridor
Hondorp, Darryl W.; Roseman, Edward F.; Manny, Bruce A.
2014-01-01
This perspective describes the major natural and anthropogenic forces driving change in the abundance and quality of fish habitats in the Huron-Erie Corridor (HEC), the Great Lakes connecting channel comprised of the St. Clair River, the Lake St. Clair, and the Detroit River. Channels connecting the Laurentian Great Lakes discharge large volumes of water equal to or greater than most other large rivers in the world that is of consistent high quality and volume, all year. Owing to creation of the St. Lawrence Seaway through the Great Lakes, the connecting channels have been modified by dredging over 200 km of deep-draft shipping lanes with a maintained depth of no less than 8.2 m. Combined with modification of their shorelines for housing and industries, use of the connecting channels for discharges of industrial and municipal wastes and shipping has resulted in numerous beneficial use impairments, such as restrictions on fish and wildlife consumption, degradation of fish and wildlife populations, and losses of fish and wildlife habitat. Various options for remediation of native fish populations and their habitats in the Great Lakes connecting channels, including construction of spawning habitat for threatened and high-value food fishes, such as lake sturgeon (Acipenser fulvescens), walleye (Sander vitreus), and lake whitefish (Coregonus clupeaformis), have been implemented successfully in two of the channels, and form the basis for further recommended research described in this article.
French, John R. P.; Jude, David J.
2001-01-01
Round gobies (Neogobius melanostomus), after successfully reproducing in the early 1990s, decimated populations of mottled sculpins (Cottus bairdi) and possibly logperch (Percina caprodes) in the St. Clair River. Studies were conducted during 1994 to determine whether diets of round and tubenose (Proterorhinus marmoratus) gobies overlapped with those of native forage fishes. In the nearshore zone (depth ≤ 1 m), round and tubenose gobies, logperch, and rainbow darters (Etheostoma caeruleum) of similar sizes (total lengths < 75 mm) consumed mainly small-sized macroinvertebrates (dipterans, Caenis, and amphipods) during June 1994. Logperch and rainbow darters were present in the nearshore zone only during this month. At the crest of the channel slope (depth = 3 m), round gobies and northern madtoms (Noturus stigmosus) ate mostly ephemeropteran nymphs (Hexagenia and Baetisca), while predation on zebra mussels (Dreissena polymorpha) and other mollusks by round gobies was minimal. Northern madtoms did not feed on mollusks. Diet overlap between round gobies and native fishes was not observed at the channel slope (depth = 5 m and 7 m) due to heavy predation on mollusks by round gobies. Young-of-the-year (YOY) round gobies migrated to deeper water in autumn and became prey of mottled sculpins and northern madtoms. Eggs and YOY of mottled sculpins may have become vulnerable to predation by both round gobies and native fishes in deeper water, since adult mottled sculpins were apparently confined to the channel with limited home range because aggressive round gobies occupied preferred shallow habitat, including spawning sites.
Expanding Larval Fish DNA Metabarcoding to All the Great Lakes
Fish larvae represent a largely untapped community for detecting and monitoring breeding non-native species, mainly due to the difficulty of identifying larvae to species through morphological methods. Molecular genetic methods offer means to identify larval specimens to species ...
Quist, M.C.; Rahel, F.J.; Hubert, W.A.
2005-01-01
Understanding factors related to the occurrence of species across multiple spatial and temporal scales is critical to the conservation and management of native fishes, especially for those species at the edge of their natural distribution. We used the concept of hierarchical faunal filters to provide a framework for investigating the influence of habitat characteristics and normative piscivores on the occurrence of 10 native fishes in streams of the North Platte River watershed in Wyoming. Three faunal filters were developed for each species: (i) large-scale biogeographic, (ii) local abiotic, and (iii) biotic. The large-scale biogeographic filter, composed of elevation and stream-size thresholds, was used to determine the boundaries within which each species might be expected to occur. Then, a local abiotic filter (i.e., habitat associations), developed using binary logistic-regression analysis, estimated the probability of occurrence of each species from features such as maximum depth, substrate composition, submergent aquatic vegetation, woody debris, and channel morphology (e.g., amount of pool habitat). Lastly, a biotic faunal filter was developed using binary logistic regression to estimate the probability of occurrence of each species relative to the abundance of nonnative piscivores in a reach. Conceptualising fish assemblages within a framework of hierarchical faunal filters is simple and logical, helps direct conservation and management activities, and provides important information on the ecology of fishes in the western Great Plains of North America. ?? Blackwell Munksgaard, 2004.
Barony, G M; Tavares, G C; Assis, G B N; Luz, R K; Figueiredo, H C P; Leal, C A G
2015-11-17
Flavobacterium columnare is responsible for disease outbreaks in freshwater fish farms. Several Brazilian native fish have been commercially exploited or studied for aquaculture purposes, including Amazon catfish Leiarius marmoratus × Pseudoplatystoma fasciatum and pacamã Lophiosilurus alexandri. This study aimed to identify the aetiology of disease outbreaks in Amazon catfish and pacamã hatcheries and to address the genetic diversity of F. columnare isolates obtained from diseased fish. Two outbreaks in Amazon catfish and pacamã hatcheries took place in 2010 and 2011. Four F. columnare strains were isolated from these fish and identified by PCR. The disease was successfully reproduced under experimental conditions for both fish species, fulfilling Koch's postulates. The genomovar of these 4 isolates and of an additional 11 isolates from Nile tilapia Oreochromis niloticus was determined by 16S rRNA restriction fragment length polymorphism PCR. The genetic diversity was evaluated by phylogenetic analysis of the 16S rRNA gene and repetitive extragenic palindromic PCR (REP-PCR). Most isolates (n = 13) belonged to genomovar II; the remaining 2 isolates (both from Nile tilapia) were assigned to genomovar I. Phylogenetic analysis and REP-PCR were able to demonstrate intragenomovar diversity. This is the first report of columnaris in Brazilian native Amazon catfish and pacamã. The Brazilian F. columnare isolates showed moderate diversity, and REP-PCR was demonstrated to be a feasible method to evaluate genetic variability in this bacterium.
Holitzki, Tara M; MacKenzie, Richard A; Wiegner, Tracy N; McDermid, Karla J
2013-09-01
Poeciliids, one of the most invasive species worldwide, are found on almost every continent and have been identified as an "invasive species of concern" in the United States, New Zealand, and Australia. Despite their global prevalence, few studies have quantified their impacts on tropical stream ecosystem structure, function, and biodiversity. Utilizing Hawaiian streams as model ecosystems, we documented how ecological structure, function, and native species abundance differed between poeciliid-free and poeciliid-invaded tropical streams. Stream nutrient yields, benthic biofilm biomass, densities of macroinvertebrates and fish, and community structures of benthic algae, macroinvertebrates, and fish were compared between streams with and without established poeciliid populations on the island of Hawai'i, Hawaii, USA. Sum nitrate (sigmaNO3(-) = NO3(-) + NO2(-)), total nitrogen, and total organic carbon yields were eight times, six times, and five times higher, respectively, in poeciliid streams than in poeciliid-free streams. Benthic biofilm ash-free dry mass was 1.5x higher in poeciliid streams than in poeciliid-free streams. Percentage contributions of chironomids and hydroptilid caddisflies to macroinvertebrate densities were lower in poeciliid streams compared to poeciliid-free streams, while percentage contributions of Cheumatopsyche analis caddisflies, Dugesia sp. flatworms, and oligochaetes were higher. Additionally, mean densities of native gobies were two times lower in poeciliid streams than in poeciliid-free ones, with poeciliid densities being approximately eight times higher than native fish densities. Our results, coupled with the wide distribution of invasive poeciliids across Hawaii and elsewhere in the tropics, suggest that poeciliids may negatively impact the ecosystem structure, function, and native species abundance of tropical streams they invade. This underscores the need for increased public awareness to prevent future introductions and for developing and implementing effective eradication and restoration strategies.
Distribution and abundance of nonnative fishes in streams of the western United States
Schade, C.B.; Bonar, Scott A.
2005-01-01
This report presents data from one of the largest standardized stream surveys conducted in he western United States, which shows that one of every four individual fish in streams of 12 western states are nonnative. The states surveyed included Arizona, California, Colorado, Idaho, Montana, Nevada, North Dakota, Oregon, South Dakota, Utah, Washington, and Wyoming. The most widely distributed and abundant nonnative fishes in the western USA were brook trout Salvelinus fontinalis, brown trout Salmo trutta, rainbow trout Oncorhynchus mykiss, common carp Cyprinus carpio, smallmouth bass Micropterus dolomieu, largemouth bass M. salmoides, green sunfish Lepomis cyanellus, fathead minnow Pimephales promelas, yellow perch Percaflavescens, yellow bullhead Ameiurus natalis, cutthroat trout O. clarkii, western mosquitofish Gambusia affinis, golden shiner Notemigonus crysoleucas, channel catfish Ictalurus punctatus, and red shiner Cyprinella lutrensis. The greatest abundance and distribution of nonnative fishes was in interior states, and the most common nonnatives were introduced for angling. Nonnative fishes were widespread in pristine to highly disturbed streams influenced by all types of land use practices. We present ranges in water temperature, flow, stream order, riparian cover, human disturbance, and other environmental conditions where the 10 most common introduced species were found. Of the total western U.S. stream length bearing fish, 50.1% contained nonnative fishes while 17.9% contained physical environment that was ranked highly or moderately disturbed by humans. Introduced fishes can adversely affect stream communities, and they are much more widespread in western U.S. streams than habitat destruction. The widespread distribution and high relative abundance of nonnative fishes and their documented negative effects suggest their management and control should elicit at least as much attention as habitat preservation in the protection of native western U.S. stream biota. ?? Copyright by the American Fisheries Society 2005.
Dellinger, Matthew J; Olson, Jared T; Holub, Bruce J; Ripley, Michael P
2018-05-11
The Chippewa Ottawa Resource Authority monitors fish contaminants in Anishinaabe (Great Lake Native American) tribal fisheries. This article updates previously reported trends in two persistent bioaccumulative toxic (PBT) substances that are the primary contributors to consumption advisory limits for these fish: methylmercury (MeHg) and polychlorinated biphenyls (PCBs). Also, we report, for the first time, an analysis of nutritional benefit bioindicators and metrics in these same Upper Great Lakes fish harvests: selenium (Se) and omega-3 fatty acids (PUFA-3s). A novel risk/benefit quantification originally presented by Ginsberg et al. is reported here to characterize the tradeoffs between fatty acid benefits and toxic MeHg health outcomes. We also report a Se benefit metric to characterize the possible protective value against MeHg neurotoxicity based on Ralston et al. Congruent with Anishinaabe cultural motivations to consume fish from their ancestral fisheries, nutritional content was high in locally caught fish and, in some respects, superior to farmed/store-bought fish. These Great Lakes fish still contained levels of PBTs that require careful education and guidance for consumers. However, the contaminant trends suggest that these fish need not be abandoned as important (both culturally and nutritionally) food sources for the Anishinaabe who harvested them. © 2018 Society for Risk Analysis.
Pollution Problem in River Kabul: Accumulation Estimates of Heavy Metals in Native Fish Species.
Ahmad, Habib; Yousafzai, Ali Muhammad; Siraj, Muhammad; Ahmad, Rashid; Ahmad, Israr; Nadeem, Muhammad Shahid; Ahmad, Waqar; Akbar, Nazia; Muhammad, Khushi
2015-01-01
The contamination of aquatic systems with heavy metals is affecting the fish population and hence results in a decline of productivity rate. River Kabul is a transcountry river originating at Paghman province in Afghanistan and inters in Khyber Pakhtunkhwa province of Pakistan and it is the major source of irrigation and more than 54 fish species have been reported in the river. Present study aimed at the estimation of heavy metals load in the fish living in River Kabul. Heavy metals including chromium, nickel, copper, zinc, cadmium, and lead were determined through atomic absorption spectrophotometer after tissue digestion by adopting standard procedures. Concentrations of these metals were recorded in muscles and liver of five native fish species, namely, Wallago attu, Aorichthys seenghala, Cyprinus carpio, Labeo dyocheilus, and Ompok bimaculatus. The concentrations of chromium, nickel, copper, zinc, and lead were higher in both of the tissues, whereas the concentration of cadmium was comparatively low. However, the concentration of metals was exceeding the RDA (Recommended Dietary Allowance of USA) limits. Hence, continuous fish consumption may create health problems for the consumers. The results of the present study are alarming and suggest implementing environmental laws and initiation of a biomonitoring program of the river.
Seebacher, Frank; Webster, Mike M.; James, Rob S.; Tallis, Jason; Ward, Ashley J. W.
2016-01-01
Local specialization can be advantageous for individuals and may increase the resilience of the species to environmental change. However, there may be trade-offs between morphological responses and physiological performance and behaviour. Our aim was to test whether habitat-specific morphology of stickleback (Gasterosteus aculeatus) interacts with physiological performance and behaviour at different salinities. We rejected the hypothesis that deeper body shape of fish from habitats with high predation pressure led to decreases in locomotor performance. However, there was a trade-off between deeper body shape and muscle quality. Muscle of deeper-bodied fish produced less force than that of shallow-bodied saltmarsh fish. Nonetheless, saltmarsh fish had lower swimming performance, presumably because of lower muscle mass overall coupled with smaller caudal peduncles and larger heads. Saltmarsh fish performed better in saline water (20 ppt) relative to freshwater and relative to fish from freshwater habitats. However, exposure to salinity affected shoaling behaviour of fish from all habitats and shoals moved faster and closer together compared with freshwater. We show that habitat modification can alter phenotypes of native species, but local morphological specialization is associated with trade-offs that may reduce its benefits. PMID:27429785
Seebacher, Frank; Webster, Mike M; James, Rob S; Tallis, Jason; Ward, Ashley J W
2016-06-01
Local specialization can be advantageous for individuals and may increase the resilience of the species to environmental change. However, there may be trade-offs between morphological responses and physiological performance and behaviour. Our aim was to test whether habitat-specific morphology of stickleback (Gasterosteus aculeatus) interacts with physiological performance and behaviour at different salinities. We rejected the hypothesis that deeper body shape of fish from habitats with high predation pressure led to decreases in locomotor performance. However, there was a trade-off between deeper body shape and muscle quality. Muscle of deeper-bodied fish produced less force than that of shallow-bodied saltmarsh fish. Nonetheless, saltmarsh fish had lower swimming performance, presumably because of lower muscle mass overall coupled with smaller caudal peduncles and larger heads. Saltmarsh fish performed better in saline water (20 ppt) relative to freshwater and relative to fish from freshwater habitats. However, exposure to salinity affected shoaling behaviour of fish from all habitats and shoals moved faster and closer together compared with freshwater. We show that habitat modification can alter phenotypes of native species, but local morphological specialization is associated with trade-offs that may reduce its benefits.
Invasive lionfish drive Atlantic coral reef fish declines.
Green, Stephanie J; Akins, John L; Maljković, Aleksandra; Côté, Isabelle M
2012-01-01
Indo-Pacific lionfish (Pterois volitans and P. miles) have spread swiftly across the Western Atlantic, producing a marine predator invasion of unparalleled speed and magnitude. There is growing concern that lionfish will affect the structure and function of invaded marine ecosystems, however detrimental impacts on natural communities have yet to be measured. Here we document the response of native fish communities to predation by lionfish populations on nine coral reefs off New Providence Island, Bahamas. We assessed lionfish diet through stomach contents analysis, and quantified changes in fish biomass through visual surveys of lionfish and native fishes at the sites over time. Lionfish abundance increased rapidly between 2004 and 2010, by which time lionfish comprised nearly 40% of the total predator biomass in the system. The increase in lionfish abundance coincided with a 65% decline in the biomass of the lionfish's 42 Atlantic prey fishes in just two years. Without prompt action to control increasing lionfish populations, similar effects across the region may have long-term negative implications for the structure of Atlantic marine communities, as well as the societies and economies that depend on them.
Invasive Lionfish Drive Atlantic Coral Reef Fish Declines
Green, Stephanie J.; Akins, John L.; Maljković, Aleksandra; Côté, Isabelle M.
2012-01-01
Indo-Pacific lionfish (Pterois volitans and P. miles) have spread swiftly across the Western Atlantic, producing a marine predator invasion of unparalleled speed and magnitude. There is growing concern that lionfish will affect the structure and function of invaded marine ecosystems, however detrimental impacts on natural communities have yet to be measured. Here we document the response of native fish communities to predation by lionfish populations on nine coral reefs off New Providence Island, Bahamas. We assessed lionfish diet through stomach contents analysis, and quantified changes in fish biomass through visual surveys of lionfish and native fishes at the sites over time. Lionfish abundance increased rapidly between 2004 and 2010, by which time lionfish comprised nearly 40% of the total predator biomass in the system. The increase in lionfish abundance coincided with a 65% decline in the biomass of the lionfish's 42 Atlantic prey fishes in just two years. Without prompt action to control increasing lionfish populations, similar effects across the region may have long-term negative implications for the structure of Atlantic marine communities, as well as the societies and economies that depend on them. PMID:22412895
Mapping the geographic distribution of non-native aquatic species is a critically important precursor to understanding the anthropogenic and environmental factors that drive freshwater biological invasions. Such efforts are often limited to local scales and/or to single species, ...
Origin and invasion of the emerging infectious pathogen Sphaerothecum destruens
Sana, Salma; Hardouin, Emilie A; Gozlan, Rodolphe E; Ercan, Didem; Tarkan, Ali Serhan; Zhang, Tiantian; Andreou, Demetra
2017-01-01
Non-native species are often linked to the introduction of novel pathogens with detrimental effects on native biodiversity. Since Sphaerothecum destruens was first discovered as a fish pathogen in the United Kingdom, it has been identified as a potential threat to European fish biodiversity. Despite this parasite’s emergence and associated disease risk, there is still a poor understanding of its origin in Europe. Here, we provide the first evidence to support the hypothesis that S. destruens was accidentally introduced to Europe from China along with its reservoir host Pseudorasbora parva via the aquaculture trade. This is the first study to confirm the presence of S. destruens in China, and it has expanded the confirmed range of S. destruens to additional locations in Europe. The demographic analysis of S. destruens and its host P. parva in their native and invasive range further supported the close association of both species. This research has direct significance and management implications for S. destruens in Europe as a non-native parasite. PMID:28831194
Offshore Fish Community: Ecological Interactions
The offshore (>80 m) fish community of Lake Superior is made up of predominately native species. The most prominent species are deepwater sculpin, kiyi, cisco, siscowet lake trout, burbot, and the exotic sea lamprey. Bloater and shortjaw cisco are also found in the offshore zone...
Morphological features to distinguish the larval stage of invasive Ruffe from native fish species
Larval fish surveys are used in a variety of research and monitoring activities, including identification of nursery habitat and invasive species early detection. Morphologically-based taxonomic identification of larvae collected from these surveys, however, is often challenging....
36 CFR 242.10 - Federal Subsistence Board.
Code of Federal Regulations, 2011 CFR
2011-07-01
... of healthy populations of fish or wildlife, to continue subsistence uses of fish or wildlife, or for... cooperative agreements or otherwise cooperate with Federal agencies, the State, Native organizations, local governmental entities, and other persons and organizations, including international entities to effectuate the...
Counihan, Timothy D.; Waite, Ian R.; Casper, Andrew F.; Ward, David L.; Sauer, Jennifer S.; Irwin, Elise R.; Chapman, Colin G.; Ickes, Brian; Paukert, Craig P.; Kosovich, John J.; Bayer, Jennifer M.
2018-01-01
Understanding trends in the diverse resources provided by large rivers will help balance tradeoffs among stakeholders and inform strategies to mitigate the effects of landscape scale stressors such as climate change and invasive species. Absent a cohesive coordinated effort to assess trends in important large river resources, a logical starting point is to assess our ability to draw inferences from existing efforts. In this paper, we use a common analytical framework to analyze data from five disparate fish monitoring programs to better understand the nature of spatial and temporal trends in large river fish assemblages. We evaluated data from programs that monitor fishes in the Colorado, Columbia, Illinois, Mississippi, and Tallapoosa rivers using non-metric dimensional scaling ordinations and associated tests to evaluate trends in fish assemblage structure and native fish biodiversity. Our results indicate that fish assemblages exhibited significant spatial and temporal trends in all five of the rivers. We also document native species diversity trends that were variable within and between rivers and generally more evident in rivers with higher species richness and programs of longer duration. We discuss shared and basin-specific landscape level stressors. Having a basic understanding of the nature and extent of trends in fish assemblages is a necessary first step towards understanding factors affecting biodiversity and fisheries in large rivers.
Waite, Ian R.; Casper, Andrew F.; Ward, David L.; Sauer, Jennifer S.; Irwin, Elise R.; Chapman, Colin G.; Ickes, Brian S.; Paukert, Craig P.; Kosovich, John J.; Bayer, Jennifer M.
2018-01-01
Understanding trends in the diverse resources provided by large rivers will help balance tradeoffs among stakeholders and inform strategies to mitigate the effects of landscape scale stressors such as climate change and invasive species. Absent a cohesive coordinated effort to assess trends in important large river resources, a logical starting point is to assess our ability to draw inferences from existing efforts. In this paper, we use a common analytical framework to analyze data from five disparate fish monitoring programs to better understand the nature of spatial and temporal trends in large river fish assemblages. We evaluated data from programs that monitor fishes in the Colorado, Columbia, Illinois, Mississippi, and Tallapoosa rivers using non-metric dimensional scaling ordinations and associated tests to evaluate trends in fish assemblage structure and native fish biodiversity. Our results indicate that fish assemblages exhibited significant spatial and temporal trends in all five of the rivers. We also document native species diversity trends that were variable within and between rivers and generally more evident in rivers with higher species richness and programs of longer duration. We discuss shared and basin-specific landscape level stressors. Having a basic understanding of the nature and extent of trends in fish assemblages is a necessary first step towards understanding factors affecting biodiversity and fisheries in large rivers. PMID:29364953
Status and historical changes in the fish community in Erhai Lake
NASA Astrophysics Data System (ADS)
Tang, Jianfeng; Ye, Shaowen; Li, Wei; Liu, Jiashou; Zhang, Tanglin; Guo, Zhiqiang; Zhu, Fengyue; Li, Zhongjie
2013-07-01
Erhai Lake is the second largest freshwater lake on the Yunnan Plateau, Southwest China. In recent decades, a number of exotic fish species have been introduced into the lake and the fish community has changed considerably. We evaluated the status of the fish community based on surveys with multimesh gillnet, trap net, and benthic fyke-net between May 2009 and April 2012. In addition, we evaluated the change in the community using historical data (1952-2010) describing the fish community and fishery harvest. The current fish community is dominated by small-sized fishes, including Pseudorasbora parva, Rhinogobius giurinus, Micropercops swinhonis, Hemiculter leucisculus, and Rhinogobius cliffordpopei. These accounted for 87.7% of the 22 546 total specimens collected. Omnivorous and carnivorous species dominated the community. A canonical correspondence analysis (CCA) plot revealed that the distribution of fishes in the lake is influenced by aquatic plants, water temperature, pH, and season. The abundance of indigenous species has declined sharply, and a majority of endemic species have been extirpated from the lake (a decrease from seven to two species). In contrast, the number of exotic species has increased since the 1960s to a total of 22 at present. The fishery harvest decreased initially following the 1960s, but has since increased due to the introduction of non-native fish and stocking of native fish. The fishery harvest was significantly correlated with total nitrogen, not total phosphorus, during the past 20 years. Based on our results, we discuss recommendations for the restoration and conservation of the fish resources in Erhai Lake.
Effects of turbidity on predation vulnerability of juvenile humpback chub to rainbow and brown trout
Ward, David L.; Morton-Starner, Rylan; Vaage, Benjamin M.
2016-01-01
Predation on juvenile native fish by introduced rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta is considered a significant threat to the persistence of endangered humpback chub Gila cypha in the Colorado River in Grand Canyon. Diet studies of rainbow and brown trout in Glen and Grand canyons indicate that these species eat native fish, but impacts are difficult to assess because predation vulnerability is highly variable depending on the physical conditions under which the predation interactions take place. We conducted laboratory experiments to evaluate how short-term predation vulnerability of juvenile humpback chub changes in response to changes in turbidity. In overnight laboratory trials, we exposed hatchery-reared juvenile humpback chub and bonytail Gila elegans (a surrogate for humpback chub) to adult rainbow and brown trout at turbidities ranging from 0 to 1,000 formazin nephlometric units. We found that turbidity as low as 25 formazin nephlometric units significantly reduced predation vulnerability of bonytail to rainbow trout and led to a 36% mean increase in survival (24–60%, 95% CI) compared to trials conducted in clear water. Predation vulnerability of bonytail to brown trout at 25 formazin nephlometric units also decreased with increasing turbidity and resulted in a 25% increase in survival on average (17–32%, 95% CI). Understanding the effects of predation by trout on endangered humpback chub is important when evaluating management options aimed at preservation of native fishes in Grand Canyon National Park. This research suggests that relatively small changes in turbidity may be sufficient to alter predation dynamics of trout on humpback chub in the mainstem Colorado River and that turbidity manipulation may warrant further investigation as a fisheries management tool.
Maret, T.R.; Robinson, C.T.; Minshall, G.W.
1997-01-01
Fish assemblages and environmental variables were evaluated from 37 least-disturbed, 1st- through 6th-order streams and springs in the upper Snake River basin, western USA. Data were collected as part of the efforts by the U.S. Geological Survey National Water Quality Assessment Program and the Idaho State University Stream Ecology Center to characterize aquatic biota and associated habitats in least-disturbed coldwater streams. Geographically, the basin comprises four ecoregions. Environmental variables constituting various spatial scales, from watershed characteristics to in stream habitat measures, were used to examine distribution patterns in fish assemblages. Nineteen fish species in the families Salmonidae, Cottidae, Cyprinidae, and Catostemidae were collected. Multivariate analyses showed high overlap in stream fish assemblages among the ecoregions. Major environmental factors determining species distributions in the basin were stream gradient, watershed size, conductivity, and percentage of the watershed covered by forest. Lowland streams (below 1,600 m in elevation), located mostly in the Snake River Basin/High Desert ecoregion, displayed different fish assemblages than upland streams (above 2,000 m elevation) in the Northern Rockies, Middle Rockies, and Northern Basin and Range ecoregions. For example, cotrids were not found in streams above 2,000 m in elevation. In addition, distinct fish assemblages were found in tributaries upstream and downstream from the large waterfall, Shoshone Falls, on the Snake River. Fish metrics explaining most of the variation among sites included the total number of species, number of native species, number of salmonid species, percent introduced species, percent cottids, and percent salmonids. Springs also exhibited different habitat conditions and fish assemblages than streams. The data suggest that the evolutionary consequences of geographic features and fish species introductions transcend the importance of ecoregion boundaries on fish distributions in the upper Snake River basin.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-14
... Reef Ecosystem Reserve Advisory Council: Native Hawaiian Representative, Ocean Related Tourism... Hawaiian). 2. One (1) Ocean-Related Tourism Representative (Ocean-Related Tourism). 3. One (1) Native...: Conservation (2), Citizen-At-Large, Ocean-Related Tourism, Recreational Fishing, Research (3), Commercial...
Aim Mapping the geographic distribution of non-native aquatic species is a critically important precursor to understanding the anthropogenic and environmental factors that drive freshwater biological invasions. Such efforts are often limited to local scales and/or to single spec...
Ecohydrological index, native fish, and climate trends and relationships in the Kansas River basin
This study sought to quantify climatological and hydrological trends and their relationship to presence and distribution of two native aquatic species in the Kansas River Basin over the past half century. Trend analyses were applied to indicators of hydrologic alteration (IHAs) ...
Larval fish surveys are used in a variety of research and monitoring activities, including identification of nursery habitat and invasive species early detection. Morphologically-based taxonomic identification of larvae collected from these surveys, however, is often challenging....
Fish and chips? Implanted transmitters help map the endangered pallid sturgeon
Chojnacki, Kimberly; DeLonay, Aaron
2011-01-01
With a flattened snout, long slender tail and rows of bony plates lining its body, the pallid sturgeon (Scaphirhynchus albus) has a unique, almost pre-historic, appearance. This endangered fish is native to the muddy, free-flowing waters of the Missouri River.
Evidence of a Shift in the Littoral Fish Community of the Sacramento-San Joaquin Delta
Farruggia, Mary Jade; Schreier, Brian; Sommer, Ted
2017-01-01
Many estuarine and freshwater ecosystems worldwide have undergone substantial changes due to multiple anthropogenic stressors. Over the past two decades, the Sacramento-San Joaquin Delta (Delta) in California, USA, saw a severe decline in pelagic fishes, a shift in zooplankton community composition, and a rapid expansion of invasive aquatic vegetation. To evaluate whether major changes have also occurred in the littoral fish community, we analyzed a beach seine survey dataset collected from 1995 to 2015 from 26 sites within the Delta. We examined changes in the Delta fish community at three different ecological scales (species, community, and biomass), using clustering analyses, trend tests, and change-point analyses. We found that the annual catch per effort for many introduced species and some native species have increased since 1995, while few experienced a decline. We also observed a steady pattern of change over time in annual fish community composition, driven primarily by a steady increase in non-native Centrarchid species. Lastly, we found that littoral fish biomass has essentially doubled over the 21-year study period, with Mississippi Silverside Menidia audens and fishes in the Centrarchidae family driving most of this increase. The changes in the catch per effort, fish community composition, and biomass per volume indicate that a shift has occurred in the Delta littoral fish community and that the same factors affecting the Delta’s pelagic food web may have been a key driver of change. PMID:28118393
Evidence of a Shift in the Littoral Fish Community of the Sacramento-San Joaquin Delta.
Mahardja, Brian; Farruggia, Mary Jade; Schreier, Brian; Sommer, Ted
2017-01-01
Many estuarine and freshwater ecosystems worldwide have undergone substantial changes due to multiple anthropogenic stressors. Over the past two decades, the Sacramento-San Joaquin Delta (Delta) in California, USA, saw a severe decline in pelagic fishes, a shift in zooplankton community composition, and a rapid expansion of invasive aquatic vegetation. To evaluate whether major changes have also occurred in the littoral fish community, we analyzed a beach seine survey dataset collected from 1995 to 2015 from 26 sites within the Delta. We examined changes in the Delta fish community at three different ecological scales (species, community, and biomass), using clustering analyses, trend tests, and change-point analyses. We found that the annual catch per effort for many introduced species and some native species have increased since 1995, while few experienced a decline. We also observed a steady pattern of change over time in annual fish community composition, driven primarily by a steady increase in non-native Centrarchid species. Lastly, we found that littoral fish biomass has essentially doubled over the 21-year study period, with Mississippi Silverside Menidia audens and fishes in the Centrarchidae family driving most of this increase. The changes in the catch per effort, fish community composition, and biomass per volume indicate that a shift has occurred in the Delta littoral fish community and that the same factors affecting the Delta's pelagic food web may have been a key driver of change.
Assessing freshwater habitat of adult anadromous alewives using multiple approaches
Mather, Martha E.; Frank, Holly J.; Smith, Joseph M.; Cormier, Roxann D.; Muth, Robert M.; Finn, John T.
2012-01-01
After centuries of disturbance, environmental professionals now recognize the need to restore coastal watersheds for native fish and protect the larger ecosystems on which fish and other aquatic biota depend. Anadromous fish species are an important component of coastal ecosystems that are often adversely affected by human activities. Restoring native anadromous fish species is a common focus of both fish and coastal watershed restoration. Yet restoration efforts have met with uneven success, often due to lack of knowledge about habitat availability and use. Using habitat surveys and radio tracking of adult anadromous alewives Alosa pseudoharengus during their spring spawning migration, we illustrate a method for quantifying habitat using multiple approaches and for relating mobile fish distribution to habitat. In the Ipswich River, Massachusetts, measuring habitat units and physical conditions at transects (width, depth, and velocity) provided an ecological basis for the interpretation of landscape patterns of fish distribution. Mapping habitat units allowed us to efficiently census habitat relevant to alewives for the entire 20.6 river kilometers of interest. Our transect data reinforced the results of the habitat unit survey and provided useful, high‐resolution ecological data for restoration efforts. Tagged alewives spent little time in riffle–run habitats and substantial time in pools, although the locations of pool occupancy varied. The insights we provide here can be used to (1) identify preferred habitats into which anadromous fish can be reintroduced in order to maximize fish survival and reproduction and (2) pinpoint habitat types in urgent need of protection or restoration.
Larvivorous fish for preventing malaria transmission.
Walshe, Deirdre P; Garner, Paul; Abdel-Hameed Adeel, Ahmed A; Pyke, Graham H; Burkot, Tom
2013-12-10
Adult anopheline mosquitoes transmit Plasmodium parasites that cause malaria. Some fish species eat mosquito larvae and pupae. In disease control policy documents, the World Health Organization includes biological control of malaria vectors by stocking ponds, rivers, and water collections near where people live with larvivorous fish to reduce Plasmodium parasite transmission. The Global Fund finances larvivorous fish programmes in some countries, and, with increasing efforts in eradication of malaria, policy makers may return to this option. We therefore assessed the evidence base for larvivorous fish programmes in malaria control. Our main objective was to evaluate whether introducing larvivorous fish to anopheline breeding sites impacts Plasmodium parasite transmission. Our secondary objective was to summarize studies evaluating whether introducing larvivorous fish influences the density and presence of Anopheles larvae and pupae in water sources, to understand whether fish can possibly have an effect. We attempted to identify all relevant studies regardless of language or publication status (published, unpublished, in press, or ongoing). We searched the following databases: the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL), published in The Cochrane Library; MEDLINE; EMBASE; CABS Abstracts; LILACS; and the metaRegister of Controlled Trials (mRCT) until 18 June 2013. We checked the reference lists of all studies identified by the above methods. We also examined references listed in review articles and previously compiled bibliographies to look for eligible studies. Randomized controlled trials and non-randomized controlled trials, including controlled before-and-after studies, controlled time series and controlled interrupted time series studies from malaria-endemic regions that introduced fish as a larvicide and reported on malaria in the community or the density of the adult anopheline population. In the absence of direct evidence of an effect on transmission, we carried out a secondary analysis on studies that evaluated the effect of introducing larvivorous fish on the density or presence of immature anopheline mosquitoes (larvae and pupae forms) in community water sources to determine whether this intervention has any potential in further research on control of malaria vectors. Three review authors screened abstracts and examined potentially relevant studies by using an eligibility form. Two review authors independently extracted data and assessed risk of bias of included studies. If relevant data were unclear or were not reported, we wrote to the trial authors for clarification. We presented data in tables, and we summarized studies that evaluated the effects of fish introduction on anopheline immature density or presence, or both. We used GRADE to summarize evidence quality. We also examined whether the authors of included studies reported on any possible adverse impact of larvivorous fish introduction on non-target native species. We found no reliable studies that reported the effects of introducing larvivorous fish on malaria infection in nearby communities, on entomological inoculation rate, or on adult Anopheles density.For the secondary analysis, we examined the effects of introducing larvivorous fish on the density and presence of anopheline larvae and pupae in community water sources. We included 12 small studies, with follow-up from 22 days to five years. Studies were conducted in a variety of settings, including localized water bodies (such as wells, domestic water containers, fishponds, and pools; six studies), riverbed pools below dams (two studies), rice field plots (three studies), and water canals (two studies). All studies were at high risk of bias.The research was insufficient to determine whether larvivorous fish reduce the density of Anopheles larvae and pupae (nine studies, unpooled data, very low quality evidence). Some studies with high stocking levels of fish seemed to arrest the increase in immature anopheline populations, or to reduce the number of immature anopheline mosquitoes, compared with controls. However, this finding was not consistent, and in studies that showed a decrease in immature anopheline populations, the effect was not consistently sustained. Larvivorous fish may reduce the number of water sources with Anopheles larvae and pupae (five studies, unpooled data, low quality evidence).None of the included studies reported effects of larvivorous fish on local native fish populations or other species. Reliable research is insufficient to show whether introducing larvivorous fish reduces malaria transmission or the density of adult anopheline mosquito populations.In research examining the effects on immature anopheline stages of introducing fish to potential malaria vector breeding sites (localized water bodies such as wells and domestic water sources, rice field plots, and water canals) weak evidence suggests an effect on the density or presence of immature anopheline mosquitoes with high stocking levels of fish, but this finding is by no means consistent. We do not know whether this translates into health benefits, either with fish alone or with fish combined with other vector control measures. Our interpretation of the current evidence is that countries should not invest in fish stocking as a larval control measure in any malaria transmission areas outside the context of carefully controlled field studies or quasi-experimental designs. Research could also usefully examine the effects on native fish and other non-target species.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burger, Joanna, E-mail: burger@biology.rutgers.edu; Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, NJ 08854-8082
Valuation of features of habitats and ecosystems usually encompasses the goods and services that ecosystems provide, but rarely also examine how people value ecological resources in terms of eco-cultural and sacred activities. The social, sacred, and cultural aspects of ecosystems are particularly important to Native Americans, but western science has rarely examined the importance of eco-cultural attributes quantitatively. In this paper I explore differences in ecosystem evaluations, and compare the perceptions and evaluations of places people go for consumptive and non-consumptive resource use with evaluations of the same qualities for religious and sacred places. Qualities of ecosystems included goods (abundantmore » fish and crabs, butterflies and flowers, clean water), services (complexity of nature, lack of radionuclides that present a health risk), and eco-cultural attributes (appears unspoiled, scenic horizons, noise-free). Native Americans and Caucasians were interviewed at a Pow Wow at Post Falls, Idaho, which is in the region with the Department of Energy's Hanford Site, known for its storage of radioactive wastes and contamination. A higher percentage of Native American subjects engaged in consumptive and religious activities than did Caucasians. Native Americans engaged in higher rates of many activities than did Caucasians, including commune with nature, pray or meditate, fish or hunt, collect herbs, and conduct vision quests or other ceremonies. For nearly all attributes, there was no difference in the relative ratings given by Native Americans for characteristics of sites used for consumption/non-consumptive activities compared to religious/sacred places. However, Caucasians rated nearly all attributes lower for religious/sacred places than they did for places where they engaged in consumptive or non-consumptive activities. Native Americans were less concerned with distance from home for consumptive/non-consumptive activities, compared to religious activities. - Research Highlights: {yields} A higher percentage of Native Americans engaged in consumptive and religious activities than did Caucasians interviewed. {yields} Caucasians rated environmental attributes as more important for consumptive and non-consumptive activities than they did for places where they engaged in religious/cultural ones. {yields} Native Americans rated environmental attributes as equally important regardless of the activities performed. {yields} Eco-cultural attributes (such as 'appears unspoiled') were rated as high as ecosystem services (e.g. unpolluted water).« less
Strecker, A.L.; Olden, J.D.; Whittier, Joanna B.; Paukert, C.P.
2011-01-01
To date, the predominant use of systematic conservation planning has been to evaluate and conserve areas of high terrestrial biodiversity. Although studies in freshwater ecosystems have received recent attention, research has rarely considered the potential tradeoffs between protecting different dimensions of biodiversity and the ecological processes that maintain diversity. We provide the first systematic prioritization for freshwaters (focusing on the highly threatened and globally distinct fish fauna of the Lower Colorado River Basin, USA) simultaneously considering scenarios of: taxonomic, functional, and phylogenetic diversity;contemporary threats to biodiversity (including interactions with nonnative species);and future climate change and human population growth. There was 75% congruence between areas of highest conservation priority for different aspects of biodiversity, suggesting that conservation efforts can concurrently achieve strong complementarity among all types of diversity. However, sizable fractions of the landscape were incongruent across conservation priorities for different diversity scenarios, underscoring the importance of considering multiple dimensions of biodiversity and highlighting catchments that contribute disproportionately to taxonomic, functional, and phylogenetic diversity in the region. Regions of projected human population growth were not concordant with conservation priorities;however, higher human population abundance will likely have indirect effects on native biodiversity by increasing demand for water. This will come in direct conflict with projected reductions in precipitation and warmer temperatures, which have substantial overlap with regions of high contemporary diversity. Native and endemic fishes in arid ecosystems are critically endangered by both current and future threats, but our results highlight the use of systematic conservation planning for the optimal allocation of limited resources that incorporates multiple and complementary conservation values describing taxonomic, functional, and phylogenetic diversity. ??2011 by the Ecological Society of America.
Strecker, Angela L.; Olden, Julian D.; Whittier, Joanna B.; Paukert, Craig P.
2011-01-01
To date, the predominant use of systematic conservation planning has been to evaluate and conserve areas of high terrestrial biodiversity. Although studies in freshwater ecosystems have received recent attention, research has rarely considered the potential trade-offs between protecting different dimensions of biodiversity and the ecological processes that maintain diversity. We provide the first systematic prioritization for freshwaters (focusing on the highly threatened and globally distinct fish fauna of the Lower Colorado River Basin, USA) simultaneously considering scenarios of: taxonomic, functional, and phylogenetic diversity; contemporary threats to biodiversity (including interactions with nonnative species); and future climate change and human population growth. There was 75% congruence between areas of highest conservation priority for different aspects of biodiversity, suggesting that conservation efforts can concurrently achieve strong complementarity among all types of diversity. However, sizable fractions of the landscape were incongruent across conservation priorities for different diversity scenarios, underscoring the importance of considering multiple dimensions of biodiversity and highlighting catchments that contribute disproportionately to taxonomic, functional, and phylogenetic diversity in the region. Regions of projected human population growth were not concordant with conservation priorities; however, higher human population abundance will likely have indirect effects on native biodiversity by increasing demand for water. This will come in direct conflict with projected reductions in precipitation and warmer temperatures, which have substantial overlap with regions of high contemporary diversity. Native and endemic fishes in arid ecosystems are critically endangered by both current and future threats, but our results highlight the use of systematic conservation planning for the optimal allocation of limited resources that incorporates multiple and complementary conservation values describing taxonomic, functional, and phylogenetic diversity.
In ecosystems where native fish species have been greatly reduced or extirpated, ecological processes such as transport of energy and nutrients across habitats or ecosystems may be lost to the detriment of remaining native species. We hypothesized that fall spawning migrations ...
A review of Ruffe (Gymnocephalus cernuus) life history and implications for spread
Ruffe (Gymnocephalus cernuus) are among the most widespread fish invaders in Lake Superior. The objective of this study was to gather information on the complete life cycle of Ruffe in both their native and non-native ranges to characterize their life history strategies. A study ...
FISH SPECIES OCCURRENCE DENSITIES IN NORTHEASTERN LAKES AND THE EXTENT OF NON-NATIVES
A species' occurrence density is the proportion or number of habitat units (lakes in this case) in a region in which it is present. Reliable estimates of occurrence density should be useful to discussions and decisions about biodiversity, rare species, and non-native invasions. T...
RED SHINER INVASION OF SOUTHEASTERN STREAMS: DYNAMICS AND ECOLOGICAL CONSEQUENCES
Red shiners, a minnow species native to streams of the central U.S., are spreading to other regions due to their widespread use as a bait-fish. Their expansion into new habitats comes at the expense of their native relatives. Red shiners are aggressive competitors for food and ...
The free-flowing Clinch and Powell River Basin, located in southwestern Virginia, United States, historically had one of the richest assemblages of native fish and freshwater mussels in the world. Nearly half of the species once residing here are now extinct, threatened, or endan...
Native Americans and the Environment: A Survey of Twentieth-Century Issues.
ERIC Educational Resources Information Center
Lewis, David Rich
1995-01-01
Land; exploitation of land; and changing Indian needs, attitudes, and religious demands define environmental issues facing modern Native Americans. Such issues are related to agriculture and ranching, forests and watersheds, hunting and fishing, water, natural resource mining and pollution, hazardous and radioactive waste storage, urbanization of…
Brunger, Lipsey T.S.; Hubert, W.A.; Rahel, F.J.
2005-01-01
Environmental gradients occur with upstream progression from plains to mountains and affect the occurrence of native warmwater fish species, but the relative importance of various environmental gradients are not defined. We assessed the relative influences of elevation, channel slope, and stream width on the occurrences of 15 native warmwater fish species among 152 reaches scattered across the North Platte River drainage of Wyoming at the interface of the Great Plains and Rocky Mountains. Most species were collected in reaches that were lower in elevation, had lower channel slopes, and were wider than the medians of the 152 sampled reaches. Several species occurred over a relatively narrow range of elevation, channel slope, or stream width among the sampled reaches, but the distributions of some species appeared to extend beyond the ranges of the sampled reaches. We identified competing logistic-regression models that accounted for the occurrence of individual species using the information-theoretic approach. Linear logistic-regression models accounted for patterns in the data better than curvilinear models for all species. The highest ranked models included channel slope for seven species, elevation for six species, stream width for one species, and both channel slope and stream width for one species. Our results suggest that different environmental gradients may affect upstream boundaries of different fish species at the interface of the Great Plains and Rocky Mountains in Wyoming.
Kumar, A. Biju; Schofield, Pam; Raj, Smrithy; Satheesh, Sima
2018-01-01
Loricariid catfishes of the genus Pterygoplichthys are native to South America and have been introduced in many localities around the world. They are freshwater fishes, but may also use low-salinity habitats such as estuaries for feeding or dispersal. Here we report results of a field survey and salinity-tolerance experiments for a population of Pterygoplichthys sp. collected in Kerala, India. In both chronic and acute salinity-tolerance trials, fish were able to withstand salinities up to 12 ppt with no mortality; however, fish transferred to salinities > 12 ppt did not survive. The experimental results provide evidence that nonnative Pterygoplichthys sp. are able to tolerate mesohaline conditions for extended periods, and can easily invade the brackish water ecosystems of the state. Further, Pterygoplichthys sp. from Kerala have greater salinity tolerance than other congeners. These data are vital to predicting the invasion of non-native fishes such as Pterygoplichthys spp. into coastal systems in Kerala and worldwide. This is particularly important as estuarine ecosystems are under threat of global climate change and sea-level rise. In light of the results of the present study and considering the reports of negative impacts of the species in invaded water bodies, management authorities may consider controlling populations and/or instituting awareness programmes to prevent the spread of this nuisance aquatic invasive species in Kerala.
Russell, B M; Wang, J; Williams, Y; Hearnden, M N; Kay, B H
2001-06-01
The ability of 2 freshwater fishes, eastern rainbow fish Melanotaenia splendida splendida and fly-specked hardyhead Craterocephalus stercusmuscarum stercusmuscarum, native to North Queensland to prey on immature Aedes aegypti was evaluated under laboratory conditions. The predation efficiency of the 2 species was compared to the exotic guppy, Poecilia reticulata, which is commonly used as a biological control agent of mosquito larvae. Of the 3 fish species tested, M. s. splendida was shown to be the most promising agent for the biological control of Ae. aegypti that breed in wells. Melanotaenia s. splendida consumed significantly greater numbers of immature Ae. aegypti than P. reticulata, irrespective of developmental stage or light conditions. Unlike C s. stercusmuscarum, M. s. splendida could be handled, transported, and kept in captivity for extended periods with negligible mortality. However, M. s. splendida was also an efficient predator of Litoria caerulea tadpoles, a species of native frog found in wells during the dry season. This result may limit the usefulness of M. s. splendida as a biological control agent of well-breeding Ae. aegypti and suggests that predacious copepods, Mesocyclops spp., are more suitable. However, the use of M. s. splendida as a mosquito control agent in containers that are unlikely to support frog populations (e.g., aquaculture tanks and drinking troughs) should be given serious consideration.
Nagelkerke, Leopold A J; van Onselen, Eline; van Kessel, Nils; Leuven, Rob S E W
2018-01-01
Invasions of Ponto-Caspian fish species into north-western European river basins accelerated since the opening of the Rhine-Main-Danube Canal in 1992. Since 2002, at least five Ponto-Caspian alien fish species have arrived in The Netherlands. Four species belong to the Gobiidae family (Neogobius fluviatilis, Neogobius melanostomus, Ponticola kessleri, and Proterorhinus semilunaris) and one to the Cyprinidae family (Romanogobio belingi). These species are expected to be potentially deleterious for the populations of four native benthic fish species: Gobio gobio (Cyprinidae), Barbatula barbatula (Nemacheilidae), Cottus perifretum, and C. rhenanus (Cottidae). Invasion success may be dependent on competitive trophic interactions with native species, which are enabled and/or constrained by feeding-related morphological traits. Twenty-two functional feeding traits were measured in nine species (in total 90 specimens). These traits were quantitatively linked to the mechanical, chemical and behavioral properties of a range of aquatic resource categories, using a previously developed food-fish model (FFM). The FFM was used to predict the trophic profile (TP) of each fish: the combined capacities to feed on each of the resource types. The most extreme TPs belonged to three alien species, indicating that they were most specialized among the studied species. Of these three, only P. kessleri overlapped with the two native Cottus species, indicating potential trophic competition. N. fluviatilis and R. belingi did not show any overlap, indicating that there is low trophic competition. The two remaining alien goby species (N. melanostomus and P. semilunaris) had average TPs and could be considered generalist feeders. They overlapped with each other and with G. gobio and B. barbatula, indicating potential trophic competition. This study suggests that both generalist and specialist species can be successful invaders. Since the FFM predicts potential interactions between species, it provides a tool to support horizon scanning and rapid risk assessments of alien species.
NATIVE AND INTRODUCED LARVAL FISHES IN SUISAN MARSH, CALIFORNIA,: THE EFFECTS OF FRESHWATER FLOW
We sampled ichthyoplankton weekly in Suisun Marsh in the San Francisco Estuary from February to June each year from 1994 to 1999. We collected approximately 227,900 fish, predominantly shimofuri goby Tridentiger bifasciatus (60%) and prickly sculpin Cottus asper (33%). Principal ...
PisCES: Pis(cine) Community Estimation Software
PisCES predicts a fish community for any NHD-Plus stream reach in the conterminous United States. PisCES utilizes HUC-based distributional information for over 1,000 nature and non-native species obtained from NatureServe, the USGS, and Peterson Field Guide to Freshwater Fishes o...
Safe Harbor: a tool to help recover topminnow and pupfish in Arizona
Douglas K. Duncan; Jeremy Voeltz
2005-01-01
The Arizona Game and Fish Department (Department) has developed a Safe Harbor Agreement (SHA) for four native fishes in Arizona. The SHA will allow Gila and Yaqui topminnow (Poeciliopsis occidentalis and P. sonoriensis) and desert and Quitobaquito pupfish (Cyprinodon macularius and C. eremus)...
The Great Lakes of North America are large aquatic ecosystems that have been greatly impacted by human activities in the 20th century. Introduction of non-native species, both advertently and inadvertently; reduction in populations through commercial fishing; habitat alternation...
Spear Fishing in Wisconsin: Multicultural Education as Symbolic Violence.
ERIC Educational Resources Information Center
New, William; Petronicolos, Loucas
2001-01-01
Describes how multicultural teacher education can preserve familiar institutional and ideological mechanisms that validate social inequalities, analyzing student discourse collected during activities concerning recent conflict between Native American groups and groups opposed to the exercise of their treaty rights to fish on nonreservation lakes.…
50 CFR 36.37 - Revenue producing visitor services.
Code of Federal Regulations, 2011 CFR
2011-10-01
... does not apply to the guiding of sport hunting or sport fishing. (b) Definitions. The following..., transportation, tours, and guides excepting the guiding of sport hunting and fishing. This also includes any..., address, and telephone number of the Native Corporation, the date of incorporation, its articles of...
Ecology of bonytail and razorback sucker and the role of off-channel habitats in their recovery
Mueller, Gordon A.
2006-01-01
This report presents new findings, updates existing information, and describes what may well represent the only practical approach to these species’ conservation and recovery. Chapter 1 provides an overview of the Colorado River system from its origin to the Gulf of California and includes a description of propagation and stocking programs which have not been described elsewhere. The report also updates what is known or suspected on the life history and ecology of these two endangered fishes. Chapter 2 describes the successful recruitment of both species at an oxbow pond on the Cibola National Wildlife Refuge in Arizona, discusses factors that contribute to completion of the life cycle of both fishes, and provides recommendations for future management of the impoundment. Chapter 3 provides historical evidence that oxbow habitats were formed historically in years of high runoff and the importance of these habitats for survival and evolution of native fishes. It also summarizes key features of habitats that can serve as sanctuaries that enhance early survival of the endangered fishes and allow the fish to complete their entire life cycles.
Brown, Larry R.; Bauer, Marissa L.
2010-01-01
Alteration of natural flow regimes is generally acknowledged to have negative effects on native biota; however, methods for defining ecologically appropriate flow regimes in managed river systems are only beginning to be developed. Understanding how past and present water management has affected rivers is an important part of developing such tools. In this paper, we evaluate how existing hydrologic infrastructure and management affect streamflow characteristics of rivers in the Central Valley, California and discuss those characteristics in the context of habitat requirements of native and alien fishes. We evaluated the effects of water management by comparing observed discharges with estimated discharges assuming no water management ("full natural runoff"). Rivers in the Sacramento River drainage were characterized by reduced winter–spring discharges and augmented discharges in other months. Rivers in the San Joaquin River drainage were characterized by reduced discharges in all months but particularly in winter and spring. Two largely unaltered streams had hydrographs similar to those based on full natural runoff of the regulated rivers. The reduced discharges in the San Joaquin River drainage streams are favourable for spawning of many alien species, which is consistent with observed patterns of fish distribution and abundance in the Central Valley. However, other factors, such as water temperature, are also important to the relative success of native and alien resident fishes. As water management changes in response to climate change and societal demands, interdisciplinary programs of research and monitoring will be essential for anticipating effects on fishes and to avoid unanticipated ecological outcomes.
Trait synergisms and the rarity, extirpation, and extinction risk of desert fishes.
Olden, Julian D; Poff, N LeRoy; Bestgen, Kevin R
2008-03-01
Understanding the causes and consequences of species extinctions is a central goal in ecology. Faced with the difficult task of identifying those species with the greatest need for conservation, ecologists have turned to using predictive suites of ecological and life-history traits to provide reasonable estimates of species extinction risk. Previous studies have linked individual traits to extinction risk, yet the nonadditive contribution of multiple traits to the entire extinction process, from species rarity to local extirpation to global extinction, has not been examined. This study asks whether trait synergisms predispose native fishes of the Lower Colorado River Basin (USA) to risk of extinction through their effects on rarity and local extirpation and their vulnerability to different sources of threat. Fish species with "slow" life histories (e.g., large body size, long life, and delayed maturity), minimal parental care to offspring, and specialized feeding behaviors are associated with smaller geographic distribution, greater frequency of local extirpation, and higher perceived extinction risk than that expected by simple additive effects of traits in combination. This supports the notion that trait synergisms increase the susceptibility of native fishes to multiple stages of the extinction process, thus making them prone to the multiple jeopardies resulting from a combination of fewer individuals, narrow environmental tolerances, and long recovery times following environmental change. Given that particular traits, some acting in concert, may differentially predispose native fishes to rarity, extirpation, and extinction, we suggest that management efforts in the Lower Colorado River Basin should be congruent with the life-history requirements of multiple species over large spatial and temporal scales.
Underwood, Zachary E.; Mandeville, Elizabeth G.; Walters, Annika W.
2016-01-01
Burbot (Lota lota) occur in the Wind River Basin in central Wyoming, USA, at the southwestern extreme of the species’ native range in North America. The most stable and successful of these populations occur in six glacially carved mountain lakes on three different tributary streams and one large main stem impoundment (Boysen Reservoir) downstream from the tributary populations. Burbot are rarely found in connecting streams and rivers, which are relatively small and high gradient, with a variety of potential barriers to upstream movement of fish. We used high-throughput genomic sequence data for 11,197 SNPs to characterize the genetic diversity, population structure, and connectivity among burbot populations on the Wind River system. Fish from Boysen Reservoir and lower basin tributary populations were genetically differentiated from those in the upper basin tributary populations. In addition, fish within the same tributary streams fell within the same genetic clusters, suggesting there is movement of fish between lakes on the same tributaries but that populations within each tributary system are isolated and genetically distinct from other populations. Observed genetic differentiation corresponded to natural and anthropogenic barriers, highlighting the importance of barriers to fish population connectivity and gene flow in human-altered linked lake-stream habitats.
Layzer, J.B.; Scott, E.M.
2006-01-01
The French Broad River originates in North Carolina, flows west into Tennessee and at its confluence with the Holston River forms the Tennessee River. Douglas Dam, located on the French Broad River 52 km above its mouth, is operated primarily for peaking hydroelectric power and flood control. Prior to completion of the dam in 1943, the lower French Broad River contained about 53 species of freshwater mussels and 100 species of fish. By 1977, the fauna in the 52-km-long tailwater was reduced to 12 species of mussels and 42 native species of fish. Improvements in tailwater conditions occurred following initiation of minimum flows in 1987, and consistent reaeration of discharge in 1993. From 1988 to 2002, we sampled three sites (4, 28, and 39 km downstream of the dam) to monitor the fish assemblage. Each year since 1988, we have collected one or more additional species, indicating continued immigration. We collected 82 native and 9 exotic species of fish overall, but the maximum of 67 species in 1 year suggests that some species reside in the tailwater at low densities or all immigrants may not successfully colonize the tailwater. There is limited potential for most extirpated species of mussels to naturally recolonize the tailwater because source populations are isolated. Consequently, 19 754 adult mussels of 19 species were introduced between 1997 and 2000. Survival of translocated mussels has been high, and successful reproduction of at least one translocated species has occurred. Additionally, four mussel species are naturally colonizing the tailwater. Colonization and recruitment of additional mussel species is expected as populations of their host fishes increase. We believe that the improved conditions of the tailwater may allow for the re-establishment of sustaining populations of 30 mussel species of historic occurrence, but the continued operation of Douglas Dam as a peaking hydroelectric project will reduce the probability of successfully reintroducing some species.
Do native brown trout and non-native brook trout interact reproductively?
NASA Astrophysics Data System (ADS)
Cucherousset, J.; Aymes, J. C.; Poulet, N.; Santoul, F.; Céréghino, R.
2008-07-01
Reproductive interactions between native and non-native species of fish have received little attention compared to other types of interactions such as predation or competition for food and habitat. We studied the reproductive interactions between non-native brook trout ( Salvelinus fontinalis) and native brown trout ( Salmo trutta) in a Pyrenees Mountain stream (SW France). We found evidence of significant interspecific interactions owing to consistent spatial and temporal overlap in redd localizations and spawning periods. We observed mixed spawning groups composed of the two species, interspecific subordinate males, and presence of natural hybrids (tiger trout). These reproductive interactions could be detrimental to the reproduction success of both species. Our study shows that non-native species might have detrimental effects on native species via subtle hybridization behavior.
Ralston, Barbara E.
2011-01-01
In the spring and summer of 2000, a series of steady discharges of water from Glen Canyon Dam on the Colorado River were used to evaluate the effects of aquatic habitat stability and water temperatures on native fish growth and survival, with a special focus on the endangered humpback chub (Gila cypha), downstream from the dam in Grand Canyon. The steady releases were bracketed by peak powerplant releases in late-May and early-September. The duration and volume of releases from the dam varied between spring and summer. The intent of the experimental hydrograph was to mimic predam river discharge patterns by including a high, steady discharge in the spring and a low, steady discharge in the summer. The hydrologic experiment was called the Low Steady Summer Flow (LSSF) experiment because steady discharges of 226 m3/s dominated the hydrograph for 4 months from June through September 2000. The experimental hydrograph was developed in response to one of the U.S. Fish and Wildlife Service's Recommended and Prudent Alternatives (RPA) in its Biological Opinion of the Operation of Glen Canyon Dam Final Environmental Impact Statement. The RPA focused on the hypothesis that seasonally adjusted steady flows were dam operations that might benefit humpback chub more than the Record of Decision operations, known as Modified Low Fluctuating Flow (MLFF) operations. Condensed timelines between planning and implementation (2 months) of the experiment and the time required for logistics, purchasing, and contracting resulted in limited data collection during the high-release part of the experiment that occurred in spring. The LSSF experiment is the longest planned hydrograph that departed from the MLFF operations since Record of Decision operations began in 1996. As part of the experiment, several studies focused on the responses of physical properties related to environments that young-of-year (YOY) native fish might occupy (for example, measuring mainstem and shoreline water temperature, and quantifying useable shorelines). The part of the hydrograph that included a habitat maintenance flow (a 4-day spike at a powerplant capacity of 877 m3/s) and sustained high releases in April and May (averaging 509 m3/s) resulted in sediment export to Lake Mead, the reservoir downstream from Glen Canyon Dam, which is outside the study area. Some mid-elevation sandbar building (between 566 and 877 m3/s stage elevations) occurred from existing sediment deposits rather than from sediment inputs from tributaries during the previous winter. Low releases in the summer combined with low tributary sediment inputs resulted in minor sediment accumulation in the study area. The September habitat maintenance flow reworked accumulated sediment and resulted in increases in the area of some backwaters. The mainstem water temperatures in the reach near the Little Colorado River during the LSSF experiment varied little from previous years. Mainstem water temperatures in western Grand Canyon average 17 to 20 degrees C. During the LSSF, backwaters warmed more than other shoreline environments during the day, but most backwaters returned to mainstem water temperatures overnight. Shoreline surface water temperatures from river mile (RM) 30 to 72 varied between 9 and 28 degrees C in the middle of the day in July. These temperatures are within the optimal temperature range for humpback chub growth and spawning, which is between 15 and 24 degrees C. How surface water temperatures transfer to subsurface water temperatures is unknown. Data collection associated with the response of fish to the 2000 LSSF hydrograph focused on fish growth and abundance along the Colorado River in Grand Canyon. The target resource, humpback chub and other native fishes, did not respond in a strongly positive or strongly negative manner to the LSSF hydrograph during the sampling period, which extended from June to September 2000. In 2000, the mean total length of YOY native fishes was similar to the mean
Emde, Sebastian; Rueckert, Sonja; Palm, Harry W.; Klimpel, Sven
2012-01-01
Non-indigenous species that become invasive are one of the main drivers of biodiversity loss worldwide. In various freshwater systems in Europe, populations of native amphipods and fish are progressively displaced by highly adaptive non-indigenous species that can perform explosive range extensions. A total of 40 Ponto-Caspian round gobies Neogobius melanostomus from the Rhine River near Düsseldorf, North Rhine-Westphalia, Germany, were examined for metazoan parasites and feeding ecology. Three metazoan parasite species were found: two Nematoda and one Acanthocephala. The two Nematoda, Raphidascaris acus and Paracuaria adunca, had a low prevalence of 2.5%. The Acanthocephala, Pomphorhynchus tereticollis, was the predominant parasite species, reaching a level of 90.0% prevalence in the larval stage, correlated with fish size. In addition, four invasive amphipod species, Corophium curvispinum (435 specimens), Dikerogammarus villosus (5,454), Echinogammarus trichiatus (2,695) and Orchestia cavimana (1,448) were trapped at the sampling site. Only D. villosus was infected with P. tereticollis at a prevalence of 0.04%. The invasive goby N. melanostomus mainly preys on these non-indigenous amphipods, and may have replaced native amphipods in the transmission of P. tereticollis into the vertebrate paratenic host. This study gives insight into a potential parasite-host system that consists mainly of invasive species, such as the Ponto-Caspian fish and amphipods in the Rhine. We discuss prospective distribution and migration pathways of non-indigenous vertebrate (round goby) and invertebrates (amphipods) under special consideration of parasite dispersal. PMID:23300895
Fire and aquatic ecosystems in forested biomes of North America
Gresswell, Robert E.
1999-01-01
Synthesis of the literature suggests that physical, chemical, and biological elements of a watershed interact with long-term climate to influence fire regime, and that these factors, in concordance with the postfire vegetation mosaic, combine with local-scale weather to govern the trajectory and magnitude of change following a fire event. Perturbation associated with hydrological processes is probably the primary factor influencing postfire persistence of fishes, benthic macroinvertebrates, and diatoms in fluvial systems. It is apparent that salmonids have evolved strategies to survive perturbations occurring at the frequency of wildland fires (100a??102 years), but local populations of a species may be more ephemeral. Habitat alteration probably has the greatest impact on individual organisms and local populations that are the least mobile, and reinvasion will be most rapid by aquatic organisms with high mobility. It is becoming increasingly apparent that during the past century fire suppression has altered fire regimes in some vegetation types, and consequently, the probability of large stand-replacing fires has increased in those areas. Current evidence suggests, however, that even in the case of extensive high-severity fires, local extirpation of fishes is patchy, and recolonization is rapid. Lasting detrimental effects on fish populations have been limited to areas where native populations have declined and become increasingly isolated because of anthropogenic activities. A strategy of protecting robust aquatic communities and restoring aquatic habitat structure and life history complexity in degraded areas may be the most effective means for insuring the persistence of native biota where the probability of large-scale fires has increased.
Pollution Problem in River Kabul: Accumulation Estimates of Heavy Metals in Native Fish Species
Ahmad, Habib; Yousafzai, Ali Muhammad; Siraj, Muhammad; Ahmad, Rashid; Ahmad, Israr; Nadeem, Muhammad Shahid; Ahmad, Waqar; Akbar, Nazia; Muhammad, Khushi
2015-01-01
The contamination of aquatic systems with heavy metals is affecting the fish population and hence results in a decline of productivity rate. River Kabul is a transcountry river originating at Paghman province in Afghanistan and inters in Khyber Pakhtunkhwa province of Pakistan and it is the major source of irrigation and more than 54 fish species have been reported in the river. Present study aimed at the estimation of heavy metals load in the fish living in River Kabul. Heavy metals including chromium, nickel, copper, zinc, cadmium, and lead were determined through atomic absorption spectrophotometer after tissue digestion by adopting standard procedures. Concentrations of these metals were recorded in muscles and liver of five native fish species, namely, Wallago attu, Aorichthys seenghala, Cyprinus carpio, Labeo dyocheilus, and Ompok bimaculatus. The concentrations of chromium, nickel, copper, zinc, and lead were higher in both of the tissues, whereas the concentration of cadmium was comparatively low. However, the concentration of metals was exceeding the RDA (Recommended Dietary Allowance of USA) limits. Hence, continuous fish consumption may create health problems for the consumers. The results of the present study are alarming and suggest implementing environmental laws and initiation of a biomonitoring program of the river. PMID:26339622
Rivero-Wendt, C L G; Miranda-Vilela, A L; Ferreira, M F N; Borges, A M; Grisolia, C K
2013-09-23
The synthetic hormone, 17-α-methyltestosterone (MT), is used in fish hatcheries to induce male monosex. Androgenic effects on various fish species have been reported; however, few studies have assessed possible genotoxic effects, although there are concerns about such effects in target and non-target species. We evaluated genotoxic and gonadal effects of MT in adult tilapia (Oreochromis niloticus) and Astyanax bimaculatus (a common native non-target fish in Brazil). Fish were fed for 28 days with ration containing MT (60 mg/L), a normal dose used in fish farming. Evaluation of MT genotoxicity was carried out through micronucleus test, nuclear abnormality, and comet assay analyses on peripheral erythrocyte cells collected by cardiac puncture. There were no significant differences in micronucleus frequencies and DNA damage in both species; however, MT caused cytogenetic toxicity in the non-target species, A. bimaculatus, with significantly increased erythrocyte nuclear abnormalities. Histopathological analyses of the female gonads of O. niloticus revealed that MT significantly inhibited the development of mature oocytes, while in A. bimaculatus it provoked significant inhibition of spermatozoa production. We concluded that discharge of fish-hatcheries water onto the surface of aquatic ecosystems should be avoided due to risks to reproduction of native species.
Introduced brown trout alter native acanthocephalan infections in native fish.
Paterson, Rachel A; Townsend, Colin R; Poulin, Robert; Tompkins, Daniel M
2011-09-01
1. Native parasite acquisition provides introduced species with the potential to modify native host-parasite dynamics by acting as parasite reservoirs (with the 'spillback' of infection increasing the parasite burdens of native hosts) or sinks (with the 'dilution' of infection decreasing the parasite burdens of native hosts) of infection. 2. In New Zealand, negative correlations between the presence of introduced brown trout (Salmo trutta) and native parasite burdens of the native roundhead galaxias (Galaxias anomalus) have been observed, suggesting that parasite dilution is occurring. 3. We used a multiple-scale approach combining field observations, experimental infections and dynamic population modelling to investigate whether native Acanthocephalus galaxii acquisition by brown trout alters host-parasite dynamics in native roundhead galaxias. 4. Field observations demonstrated higher infection intensity in introduced trout than in native galaxias, but only small, immature A. galaxii were present in trout. Experimental infections also demonstrated that A. galaxii does not mature in trout, although parasite establishment and initial growth were similar in the two hosts. Taken together, these results support the hypothesis that trout may serve as an infection sink for the native parasite. 5. However, dynamic population modelling predicts that A. galaxii infections in native galaxias should at most only be slightly reduced by dilution in the presence of trout. Rather, model exploration indicates parasite densities in galaxias are highly sensitive to galaxias predation on infected amphipods, and to relative abundances of galaxias and trout. Hence, trout presence may instead reduce parasite burdens in galaxias by either reducing galaxias density or by altering galaxias foraging behaviour. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.
Kao, Yu-Chun; Madenjian, Charles P.; Bunnell, David B.; Lofgren, Brent M.; Perroud, Marjorie
2015-01-01
We used a bioenergetics modeling approach to investigate potential effects of climate change on the growth of two economically important native fishes: yellow perch (Perca flavescens), a cool-water fish, and lake whitefish (Coregonus clupeaformis), a cold-water fish, in deep and oligotrophic Lakes Michigan and Huron. For assessing potential changes in fish growth, we contrasted simulated fish growth in the projected future climate regime during the period 2043-2070 under different prey availability scenarios with the simulated growth during the baseline (historical reference) period 1964-1993. Results showed that effects of climate change on the growth of these two fishes are jointly controlled by behavioral thermoregulation and prey availability. With the ability of behavioral thermoregulation, temperatures experienced by yellow perch in the projected future climate regime increased more than those experienced by lake whitefish. Thus simulated future growth decreased more for yellow perch than for lake whitefish under scenarios where prey availability remains constant into the future. Under high prey availability scenarios, simulated future growth of these two fishes both increased but yellow perch could not maintain the baseline efficiency of converting prey consumption into body weight. We contended that thermal guild should not be the only factor used to predict effects of climate change on the growth of a fish, and that ecosystem responses to climate change should be also taken into account.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maskill, Mark
2003-03-01
Mitigation Objective 1: Produce Native Westslope Cutthroat Trout at Creston NFH--Task: Acquire eggs and rear up to 100,000 Westslope Cutthroat trout annually for offsite mitigation stocking. Accomplishments: A total of 150,000 westslope cutthroat eggs (M012 strain) were acquired from the State of Montana Washoe Park State Fish Hatchery in July 2001 for this objective. Another 120,000 westslope cutthroat eggs were taken from feral fish at Rogers Lake in May of 2001 by the Creston Hatchery crew. The fish were reared using approved fish culture techniques as defined in the U.S. Department of the Interior Fish Hatchery Management guidelines. Post releasemore » survival and angler success is monitored annually by Montana Fish Wildlife and Parks (MFWP) and the Confederated Salish and Kootenai Tribe (CSKT). Stocking numbers and locations may vary yearly based on results of biological monitoring. Mitigation Objective 2: Produce Rainbow Trout at Creston NFH--Task: Acquire and rear up to 100,000 Rainbow trout annually for offsite mitigation in closed basin waters. Accomplishments: A total of 50,500 rainbow trout eggs (Arlee strain) were acquired from the State of Montana Arlee State Fish Hatchery in December 2001 for this objective. The fish were reared using approved fish culture techniques as defined in the U.S. Department of the Interior Fish Hatchery Management guidelines. Arlee rainbow trout are being used for this objective because the stocking locations are terminal basin reservoirs and habitat conditions and returns to creel are unsuitable for native cutthroat. Post release survival and angler success is monitored annually by the Confederated Salish and Kootenai Tribe (CSKT). Stocking numbers and locations may vary yearly based on results of biological monitoring.« less
Creative Photography - Wildlife
2016-03-25
Black skimmers fly just above the waterline as they hunt for fish at Merritt Island National Wildlife Refuge in Florida. NASA’s Kennedy Space Center shares boundaries with the refuge, which is home to more than 330 native and migratory bird species, along with 25 mammal, 117 fish, and 65 amphibian and reptile species.
Creative Photography - Wildlife
2016-03-25
An osprey, clutching a fish, pauses for a meal atop a metal structure at NASA’s Kennedy Space Center in Florida. The spaceport shares boundaries with the Merritt Island National Wildlife Refuge, which is home to more than 330 native and migratory bird species, along with 25 mammal, 117 fish, and 65 amphibian and reptile species.
Creative Photography - Wildlife
2016-03-25
A snowy egret successfully catches a small fish in a shallow waterway at Merritt Island National Wildlife Refuge in Florida. NASA’s Kennedy Space Center shares boundaries with the refuge, which is home to more than 330 native and migratory bird species, along with 25 mammal, 117 fish, and 65 amphibian and reptile species.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Conservation of Fish, Wildlife, and Their Habitat, Chugach National Forest, Alaska § 241.21 Definitions. For... refers to the Alaska National Interest Lands Conservation Act (16 U.S.C. 3101 et seq.) Federal lands mean... to a Native corporation or person. Fish and Wildlife means any member of the animal kingdom...
Code of Federal Regulations, 2012 CFR
2012-07-01
... Conservation of Fish, Wildlife, and Their Habitat, Chugach National Forest, Alaska § 241.21 Definitions. For... refers to the Alaska National Interest Lands Conservation Act (16 U.S.C. 3101 et seq.) Federal lands mean... to a Native corporation or person. Fish and Wildlife means any member of the animal kingdom...
Code of Federal Regulations, 2010 CFR
2010-07-01
... Conservation of Fish, Wildlife, and Their Habitat, Chugach National Forest, Alaska § 241.21 Definitions. For... refers to the Alaska National Interest Lands Conservation Act (16 U.S.C. 3101 et seq.) Federal lands mean... to a Native corporation or person. Fish and Wildlife means any member of the animal kingdom...
Code of Federal Regulations, 2013 CFR
2013-07-01
... Conservation of Fish, Wildlife, and Their Habitat, Chugach National Forest, Alaska § 241.21 Definitions. For... refers to the Alaska National Interest Lands Conservation Act (16 U.S.C. 3101 et seq.) Federal lands mean... to a Native corporation or person. Fish and Wildlife means any member of the animal kingdom...
Code of Federal Regulations, 2014 CFR
2014-07-01
... Conservation of Fish, Wildlife, and Their Habitat, Chugach National Forest, Alaska § 241.21 Definitions. For... refers to the Alaska National Interest Lands Conservation Act (16 U.S.C. 3101 et seq.) Federal lands mean... to a Native corporation or person. Fish and Wildlife means any member of the animal kingdom...
Linking hydroclimate to fish phenology and habitat use with ichthyographs
Rebecca L. Flitcroft; Sarah L. Lewis; Ivan Arismendi; Rachel LovellFord; Mary V. Santelmann; Mohammad Safeeq; Gordon Grant; Kyle A. Young
2016-01-01
Streamflow and water temperature (hydroclimate) influence the life histories of aquatic biota. The relationship between streamflow and temperature varies with climate, hydrogeomorphic setting, and season. Life histories of native fishes reflect, in part, their adaptation to regional hydroclimate (flow and water temperature), local habitats, and natural disturbance...
Context
EPA Region 10, which comprises Alaska, Washington, Idaho, and Oregon, has 269 federally recognized Native American Tribes. It is has been documented that Tribal members consume much larger quantities of fish than the general population. ORD's Human Studies Division...
Braun, Burga; Richert, Inga; Szewzyk, Ulrich
2009-10-01
Iron-depositing bacteria play an important role in technical water systems (water wells, distribution systems) due to their intense deposition of iron oxides and resulting clogging effects. Pedomicrobium is known as iron- and manganese-oxidizing and accumulating bacterium. The ability to detect and quantify members of this species in biofilm communities is therefore desirable. In this study the fluorescence in situ hybridization (FISH) method was used to detect Pedomicrobium in iron and manganese incrusted biofilms. Based on comparative sequence analysis, we designed and evaluated a specific oligonucleotide probe (Pedo 1250) complementary to the hypervariable region 8 of the 16S rRNA gene for Pedomicrobium. Probe specificities were tested against 3 different strains of Pedomicrobium and Sphingobium yanoikuyae as non-target organism. Using optimized conditions the probe hybridized with all tested strains of Pedomicrobium with an efficiency of 80%. The non-target organism showed no hybridization signals. The new FISH probe was applied successfully for the in situ detection of Pedomicrobium in different native, iron-depositing biofilms. The hybridization results of native bioflims using probe Pedo_1250 agreed with the results of the morphological structure of Pedomicrobium bioflims based on scanning electron microscopy.
DNA barcodes of the native ray-finned fishes in Taiwan.
Chang, Chia-Hao; Shao, Kwang-Tsao; Lin, Han-Yang; Chiu, Yung-Chieh; Lee, Mao-Ying; Liu, Shih-Hui; Lin, Pai-Lei
2017-07-01
Species identification based on the DNA sequence of a fragment of the cytochrome c oxidase subunit I gene in the mitochondrial genome, DNA barcoding, is widely applied to assist in sustainable exploitation of fish resources and the protection of fish biodiversity. The aim of this study was to establish a reliable barcoding reference database of the native ray-finned fishes in Taiwan. A total of 2993 individuals, belonging to 1245 species within 637 genera, 184 families and 29 orders of ray-finned fishes and representing approximately 40% of the recorded ray-finned fishes in Taiwan, were PCR amplified at the barcode region and bidirectionally sequenced. The mean length of the 2993 barcodes is 549 bp. Mean congeneric K2P distance (15.24%) is approximately 10-fold higher than the mean conspecific one (1.51%), but approximately 1.4-fold less than the mean genetic distance between families (20.80%). The Barcode Index Number (BIN) discordance report shows that 2993 specimens represent 1275 BINs and, among them, 86 BINs are singletons, 570 BINs are taxonomically concordant, and the other 619 BINs are taxonomically discordant. Barcode gap analysis also revealed that more than 90% of the collected fishes in this study can be discriminated by DNA barcoding. Overall, the barcoding reference database established by this study reveals the need for taxonomic revisions and voucher specimen rechecks, in addition to assisting in the management of Taiwan's fish resources and diversity. © 2016 John Wiley & Sons Ltd.
Quist, M.C.; Bower, M.R.; Hubert, W.A.
2007-01-01
Black spot is a common disease syndrome of freshwater fishes. This study provides information on the rank of density of the black spot agent and opercular bone alterations associated with at least one digenean, Uvulifer sp., infecting native and non-native catostomids and cyprinids of the Upper Colorado River Basin. We evaluated the density rank of pigmented metacercariae and associated alterations in the operculum of the bluehead sucker Catostomus discobolus, flannelmouth sucker C. latipinnis, white sucker C. commersoni, catostomid hybrids, roundtail chub Gila robusta, and creek chub Semotilus atromaculatus, sampled from Muddy Creek, Wyoming, USA in 2003 or 2004. All fish species contained individuals that exhibited gross signs of the black spot agent. Bluehead and flannelmouth suckers had 100% prevalence of infection. Although the other suckers and chubs contained encysted metacercariae in at least one individual, the presence of pigmented metacercariae was not apparent (i.e. based on gross observations) in many individuals. Catostomids had higher densities of metacercariae than cyprinids, as shown by frequency distributions of density ranks. Opercular holes (i.e. holes that completely penetrated the opercle and were in direct association with the pigment associated metacercariae) and pockets (depressions on the external surface of the opercle associated with metacercariae) were abundant among catostomids but rare among cyprinids. ?? Inter-Research 2007.
Quist, Michael C; Bower, Michael R; Hubert, Wayne A
2007-12-13
Black spot is a common disease syndrome of freshwater fishes. This study provides information on the rank of density of the black spot agent and opercular bone alterations associated with at least one digenean, Uvulifer sp., infecting native and non-native catostomids and cyprinids of the Upper Colorado River Basin. We evaluated the density rank of pigmented metacercariae and associated alterations in the operculum of the bluehead sucker Catostomus discobolus, flannelmouth sucker C. latipinnis, white sucker C. commersoni, catostomid hybrids, roundtail chub Gila robusta, and creek chub Semotilus atromaculatus, sampled from Muddy Creek, Wyoming, USA in 2003 or 2004. All fish species contained individuals that exhibited gross signs of the black spot agent. Bluehead and flannelmouth suckers had 100% prevalence of infection. Although the other suckers and chubs contained encysted metacercariae in at least one individual, the presence of pigmented metacercariae was not apparent (i.e. based on gross observations) in many individuals. Catostomids had higher densities of metacercariae than cyprinids, as shown by frequency distributions of density ranks. Opercular holes (i.e. holes that completely penetrated the opercle and were in direct association with the pigment associated metacercariae) and pockets (depressions on the external surface of the opercle associated with metacercariae) were abundant among catostomids but rare among cyprinids.
Southern marl prairies conceptual ecological model
Davis, S.M.; Loftus, W.F.; Gaiser, E.E.; Huffman, A.E.
2005-01-01
About 190,000 ha of higher-elevation marl prairies flank either side of Shark River Slough in the southern Everglades. Water levels typically drop below the ground surface each year in this landscape. Consequently, peat soil accretion is inhibited, and substrates consist either of calcitic marl produced by algal periphyton mats or exposed limestone bedrock. The southern marl prairies support complex mosaics of wet prairie, sawgrass sawgrass (Cladium jamaicense), tree islands, and tropical hammock communities and a high diversity of plant species. However, relatively short hydroperiods and annual dry downs provide stressful conditions for aquatic fauna, affecting survival in the dry season when surface water is absent. Here, we present a conceptual ecological model developed for this landscape through scientific concensus, use of empirical data, and modeling. The two major societal drivers affecting the southern marl prairies are water management practices and agricultural and urban development. These drivers lead to five groups of ecosystem stressors: loss of spatial extent and connectivity, shortened hydroperiod and increased drought severity, extended hydroperiod and drying pattern reversals, introduction and spread of non-native trees, and introduction and spread of non-native fishes. Major ecological attributes include periphyton mats, plant species diversity and community mosaic, Cape Sable seaside sparrow (Ammodramus maritimus mirabilis), marsh fishes and associated aquatic fauna prey base, American alligator (Alligator mississippiensis), and wading bird early dry season foraging. Water management and development are hypothesized to have a negative effect on the ecological attributes of the southern marl prairies in the following ways. Periphyton mats have decreased in cover in areas where hydroperiod has been significantly reduced and changed in community composition due to inverse responses to increased nutrient availability. Plant species diversity and community mosaics have changed due to shifting gradients to more terrestrial or more aquatic communities, displacement of native communities by non-natives, expansion of woody plants, high-intensity dry season fires, tree-island burnout, and reduced microtopography resulting from alligator population decline. Cape Sable seaside sparrow populations are threatened by nest destruction resulting from extended hydroperiods, drying pattern reversals, and high intensity dry season fires, as well as by the expansion of woody plants into graminoid wetland habitats. Populations of marsh fishes and associated aquatic fauna that constitute the aquatic prey base for higher vertebrates have decreased in density and changed in species composition and size structure due to loss of wetland spatial extent, shortened hydroperiod, increased drought severity, loss of aquatic drought refugia in solution holes and alligator holes, and spread of exotic fishes. American alligator populations have declined in the Rocky Glades, and alligator holes have filled with sediment, as a result of shortened hydroperiod and increased drought severity. Habitat options for wading birds to forage during the early dry season and during unusually wet years have been reduced due to loss of spatial extent and shortened hydroperiod.
Waite, I.R.; Carpenter, K.D.
2000-01-01
As part of the U.S. Geological Survey's National Water-Quality Assessment Program, fish were collected from 24 selected stream sites in the Willamette Basin during 1993-1995 to determine the composition of the fish assemblages and their relation to the chemical and physical environment. Variance in fish relative abundance was greater among all sites than among spatially distinct reaches within a site (spatial variation) or among multiple sampled years at a site (temporal variation). Therefore, data from a single reach in an individual year was considered to be a reliable estimator of the fish assemblage structure at a site when the data were normalized by percent relative abundance. Multivariate classification and ordination were used to examine patterns in environmental variables and fish relative abundance over differing spatial scales (among versus within ecoregions). Across all ecoregions (all sites), fish assemblages were primarily structured along environmental gradients of water temperature and stream gradient (coldwater, high-gradient forested sites versus warmwater, low-gradient Willamette Valley sites); this pattern superseded patterns that were ecoregion specific. Water temperature, dissolved oxygen, and physical habitat (e.g., riparian canopy and percent riffles) were associated with patterns of fish assemblages across all ecoregions; however, pesticide and total phosphorus concentrations were more important than physical habitat within the Willamette Valley ecoregion. Consideration of stream site stratification (e.g., stream size, ecoregion, and stream gradient), identification of fish to species level (particularly the sculpin family), and detailed measurement of habitat, diurnal dissolved oxygen, and water temperature were critical in evaluating the composition of fish assemblages in relation to land use. In general, these low-gradient valley streams typical of other agricultural regions had poor riparian systems and showed increases in water temperature, nutrients, and fine grain sediments that were associated with degradation in the native fish assemblages. There was an association of high abundances of introduced species and high percent external abnormalities in medium-sized river sites of mixed land use and high abundances of tolerant species in small streams of predominantly agricultural land use.
Invasive hybridization in a threatened species is accelerated by climate change
NASA Astrophysics Data System (ADS)
Muhlfeld, Clint C.; Kovach, Ryan P.; Jones, Leslie A.; Al-Chokhachy, Robert; Boyer, Matthew C.; Leary, Robb F.; Lowe, Winsor H.; Luikart, Gordon; Allendorf, Fred W.
2014-07-01
Climate change will decrease worldwide biodiversity through a number of potential pathways, including invasive hybridization (cross-breeding between invasive and native species). How climate warming influences the spread of hybridization and loss of native genomes poses difficult ecological and evolutionary questions with little empirical information to guide conservation management decisions. Here we combine long-term genetic monitoring data with high-resolution climate and stream temperature predictions to evaluate how recent climate warming has influenced the spatio-temporal spread of human-mediated hybridization between threatened native westslope cutthroat trout (Oncorhynchus clarkii lewisi) and non-native rainbow trout (Oncorhynchus mykiss), the world's most widely introduced invasive fish. Despite widespread release of millions of rainbow trout over the past century within the Flathead River system, a large relatively pristine watershed in western North America, historical samples revealed that hybridization was prevalent only in one (source) population. During a subsequent 30-year period of accelerated warming, hybridization spread rapidly and was strongly linked to interactions between climatic drivers--precipitation and temperature--and distance to the source population. Specifically, decreases in spring precipitation and increases in summer stream temperature probably promoted upstream expansion of hybridization throughout the system. This study shows that rapid climate warming can exacerbate interactions between native and non-native species through invasive hybridization, which could spell genomic extinction for many species.
Fricke, Ronald; Allen, Gerald R; Andréfouët, Serge; Chen, Wei-Jen; Hamel, Mélanie A; Laboute, Pierre; Mana, Ralph; Hui, Tan Heok; Uyeno, Daisuke
2014-06-08
A checklist of the marine and estuarine fishes of Madang District is presented, combining both previous and new records. After the recent PAPUA NIUGINI 2012 expedition, a total of 1337 species in 129 families have been recorded from the region. One species and one family is not native (Cichlidae: Oreochromis mossambicus), but has been introduced. The native fish fauna of Madang therefore consists of 1336 species in 128 families. The largest families are the Gobiidae, Labridae, Pomacentridae, Apogonidae, Serranidae, Blenniidae, Chaetodontidae, Syngnathidae and Muraenidae, Scorpaenidae and Lutjanidae, Myctophidae, Acanthuridae, Scaridae, Holocentridae, Carangidae, Pomacanthidae and Tetraodontidae, and Caesionidae. A total of 820 fish species (61.4 % of the total marine and estuarine fish fauna) are recorded from Madang for the first time. The fish fauna of Madang includes a total of 187 species of transitional waters and 1326 species in marine habitats. A total of 156 species of the marine or estuarine species also occurs in freshwater. Zoogeographically, 1271 species have a wide distribution range, most frequently a broad Indo-West Pacific distribution. Among the remaining species, only 8 are endemic to Madang District. Anthropogenic threats to the fish fauna and habitats of Madang District include extensive fishing in Madang Lagoon, sometimes with destructive fishing practices; the discharge of untreated sewage of human settlements, mining and industrial developments into the lagoon and nearby oceanic habitats; and destruction of mangrove habitats by extensive construction work on the shores. These anthropogenic threats may call for conservation and monitoring measures in the near future.
Non-native fish introductions and the reversibility of amphibian declines in the Sierra Nevada
Roland A. Knapp
2004-01-01
Amphibians are declining worldwide for a variety of reasons, including habitat alteration, introduction of non-native species, disease, climate change, and environmental contaminants. Amphibians often play important roles in structuring ecosystems, and, as a result, amphibian population declines or extinctions are likely to affect other trophic levels (Matthews and...
The free-flowing Clinch and Powell River basin, located in southwestern Virginia, U.S.A., historically had one of the richest assemblages of native fish and freshwater mussels in the world. Nearly half of the species once residing here are now extinct, threatened or endangered....
Factors Mediating co-occurrence of an economically valuable introduced fish and its native frog prey
Rosemary Hartman; Karen Pope; Sharon Lawler
2013-01-01
Habitat characteristics mediate predator-prey coexistence in many ecological systemd but are seldom considered in species introductions. When economically important introduced predators are stocked despite known impacts on native species, understanding the role of refuges, landscape configurations, and community interactions can inform habitat management plans. We...
Vij, Shubha; Kuhl, Heiner; Kuznetsova, Inna S.; Komissarov, Aleksey; Yurchenko, Andrey A.; Van Heusden, Peter; Singh, Siddharth; Thevasagayam, Natascha M.; Prakki, Sai Rama Sridatta; Purushothaman, Kathiresan; Saju, Jolly M.; Jiang, Junhui; Mbandi, Stanley Kimbung; Jonas, Mario; Hin Yan Tong, Amy; Mwangi, Sarah; Lau, Doreen; Ngoh, Si Yan; Liew, Woei Chang; Shen, Xueyan; Hon, Lawrence S.; Drake, James P.; Boitano, Matthew; Hall, Richard; Chin, Chen-Shan; Lachumanan, Ramkumar; Korlach, Jonas; Trifonov, Vladimir; Kabilov, Marsel; Tupikin, Alexey; Green, Darrell; Moxon, Simon; Garvin, Tyler; Sedlazeck, Fritz J.; Vurture, Gregory W.; Gopalapillai, Gopikrishna; Kumar Katneni, Vinaya; Noble, Tansyn H.; Scaria, Vinod; Sivasubbu, Sridhar; Jerry, Dean R.; O'Brien, Stephen J.; Schatz, Michael C.; Dalmay, Tamás; Turner, Stephen W.; Lok, Si; Christoffels, Alan; Orbán, László
2016-01-01
We report here the ~670 Mb genome assembly of the Asian seabass (Lates calcarifer), a tropical marine teleost. We used long-read sequencing augmented by transcriptomics, optical and genetic mapping along with shared synteny from closely related fish species to derive a chromosome-level assembly with a contig N50 size over 1 Mb and scaffold N50 size over 25 Mb that span ~90% of the genome. The population structure of L. calcarifer species complex was analyzed by re-sequencing 61 individuals representing various regions across the species’ native range. SNP analyses identified high levels of genetic diversity and confirmed earlier indications of a population stratification comprising three clades with signs of admixture apparent in the South-East Asian population. The quality of the Asian seabass genome assembly far exceeds that of any other fish species, and will serve as a new standard for fish genomics. PMID:27082250
Chapman, Duane
2004-01-01
You've probably heard the adage, "When life gives you lemons, make lemonade!" Missouri has been given some lemons in the form of bighead and silver carp. These large, plankton eating fish, native to Asia, were imported into Arkansas in the 1970s to control water quality in fish farms and sewage treatment facilities. It didn't take long for the fish to escape to the wild, and their populations have been increasing ever since.
Effects of land use intensification on fish assemblages in Mediterranean climate streams.
Matono, P; Sousa, D; Ilhéu, M
2013-11-01
Southern Portugal is experiencing a rapid change in land use due to the spread of intensive farming systems, namely olive production systems, which can cause strong negative environmental impacts and affect the ecological integrity of aquatic ecosystems. This study aimed to identify the main environmental disturbances related with olive grove intensification on Mediterranean-climate streams in southern Portugal, and to evaluate their effects on fish assemblage structure and integrity. Twenty-six stream sites within the direct influence of traditional, intensive, and hyper-intensive olive groves were sampled. Human-induced disturbances were analyzed along the olive grove intensity gradient. The integrity of fish assemblages was evaluated by comparison with an independent set of least disturbed reference sites, considering metrics and guilds, based on multivariate analyses. Along the gradient of olive grove intensification, the study observed overall increases in human disturbance variables and physicochemical parameters, especially organic/nutrient enrichment, sediment load, and riparian degradation. Animal load measured the impact of livestock production. This variable showed an opposite pattern, since traditional olive groves are often combined with high livestock production and are used as grazing pasture by the cattle, unlike more intensive olive groves. Stream sites influenced by olive groves were dominated by non-native and tolerant fish species, while reference sites presented higher fish richness, density and were mainly occupied by native and intolerant species. Fish assemblage structure in olive grove sites was significantly different from the reference set, although significant differences between olive grove types were not observed. Bray-Curtis similarities between olive grove sites and references showed a decreasing trend in fish assemblage integrity along the olive grove intensification gradient. Olive production, even in traditional groves, led to multiple in-stream disturbances, whose cumulative effects promoted the loss of biota integrity. The impacts of low intensity traditional olive groves on aquatic ecosystems can be much greater when they are coupled with livestock production. This paper recommends best practices to reduce negative impacts of olive production on streams, contributing to guide policy decision-makers in agricultural and water management.
Review of the negative influences of non-native salmonids on native fish species
Turek, Kelly C.; Pegg, Mark A.; Pope, Kevin L.
2013-01-01
Non-native salmonids are often introduced into areas containing species of concern, yet a comprehensive overview of the short- and long-term consequences of these introductions is lacking in the Great Plains. Several authors have suggested that non-native salmonids negatively inflfluence species of concern. The objective of this paper is to review known interactions between non-native salmonids and native fifishes, with a focus on native species of concern. After an extensive search of the literature, it appears that in many cases non-native salmonids do negatively inflfl uence species of concern (e.g., reduce abundance and alter behavior) via different mechanisms (e.g., predation and competition). However, there are some instances in which introduced salmonids have had no perceived negative inflfl uence on native fifi shes. Unfortunately, the majority of the literature is circumstantial, and there is a need to experimentally manipulate these interactions.
Sudthongkong, C; Miyata, M; Miyazaki, T
2002-11-01
Tropical iridovirus infection causes severe epizootic resulting in mass mortalities and large economic losses in freshwater ornamental fishes cultured in Southeast Asian countries, in wild fish seedlings captured in South China Sea, and in marine fishes farmed in Japan, Singapore, and Thailand. All of tropical iridovirus-infected fishes histopathologically showed the systemic formation of inclusion body-bearing cells and necrosis of virus-infected splenocytes and hematopoietic cells. We designed primer sets for the ATPase gene and the major capsid protein (MCP) gene and sequenced the PCR products derived from 5 iridovirus isolates from sea bass in South China Sea, red sea bream in Japan, brown-spotted grouper with a grouper sleepy disease in Thailand, dwarf gourami from Malaysia and African lampeye from Sumatra Island, Indonesia. The ATPase gene and the MCP gene of these 5 viral isolates were highly homologous (> 95.8%, > 94.9% identity, respectively) and the deduced amino acid sequences of the ATPase and the MCP were also highly identical (> 98.1%, > 97.2% identity, respectively). Based on the high homology, these 5 isolates of tropical iridovirus from various fishes in geographically different regions were determined to have a single origin and to be native to Southeast Asian regions. However, these sequences were far different from those of members of the genera Ranavirus, Lymphocystivirus and Iridovirus in the Family Iridoviridae. We propose a new genus "Tropivirus" for tropical iridovirus in the Family Iridoviridae.
2013-06-01
to short-term behavioral responses and no effects that would be measurable at a population level have been documented. Fish in their native...the sustainable multipurpose use of natural resources (hunting, fishing , trapping, and non- consumptive uses) on military lands, subject to safety...support fish populations year-round, as they freeze in winter or when iced over and lack sufficient dissolved oxygen for fish to survive (USARAK 2004-1
Introduced species and their missing parasites
Torchin, Mark E.; Lafferty, Kevin D.; Dobson, Andrew P.; McKenzie, Valerie J.; Kuris, Armand M.
2003-01-01
Damage caused by introduced species results from the high population densities and large body sizes that they attain in their new location. Escape from the effects of natural enemies is a frequent explanation given for the success of introduced species. Because some parasites can reduce host density and decrease body size, an invader that leaves parasites behind and encounters few new parasites can experience a demographic release and become a pest. To test whether introduced species are less parasitized, we have compared the parasites of exotic species in their native and introduced ranges, using 26 host species of molluscs, crustaceans, fishes, birds, mammals, amphibians and reptiles. Here we report that the number of parasite species found in native populations is twice that found in exotic populations. In addition, introduced populations are less heavily parasitized (in terms of percentage infected) than are native populations. Reduced parasitization of introduced species has several causes, including reduced probability of the introduction of parasites with exotic species (or early extinction after host establishment), absence of other required hosts in the new location, and the host-specific limitations of native parasites adapting to new hosts.
Larvivorous fish for preventing malaria transmission
Walshe, Deirdre P; Garner, Paul; Adeel, Ahmed A; Pyke, Graham H; Burkot, Thomas R
2017-01-01
Background Adult female Anopheles mosquitoes can transmit Plasmodium parasites that cause malaria. Some fish species eat mosquito larvae and pupae. In disease control policy documents, the World Health Organization (WHO) includes biological control of malaria vectors by stocking ponds, rivers, and water collections near where people live with larvivorous fish to reduce Plasmodium parasite transmission. In the past, the Global Fund has financed larvivorous fish programmes in some countries, and, with increasing efforts in eradication of malaria, policymakers may return to this option. Therefore, we assessed the evidence base for larvivorous fish programmes in malaria control. Objectives To evaluate whether introducing larvivorous fish to anopheline larval habitats impacts Plasmodium parasite transmission. We also sought to summarize studies that evaluated whether introducing larvivorous fish influences the density and presence of Anopheles larvae and pupae in water sources. Search methods We searched the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library; MEDLINE (PubMed); Embase (Ovid); CABS Abstracts; LILACS; and the metaRegister of Controlled Trials (mRCT) up to 6 July 2017. We checked the reference lists of all studies identified by the search. We examined references listed in review articles and previously compiled bibliographies to look for eligible studies. Also we contacted researchers in the field and the authors of studies that met the inclusion criteria for additional information regarding potential studies for inclusion and ongoing studies. This is an update of a Cochrane Review published in 2013. Selection criteria Randomized controlled trials (RCTs) and non-RCTs, including controlled before-and-after studies, controlled time series, and controlled interrupted time series studies from malaria-endemic regions that introduced fish as a larvicide and reported on malaria in the community or the density of the adult anopheline population. In the absence of direct evidence of an effect on transmission, we performed a secondary analysis on studies that evaluated the effect of introducing larvivorous fish on the density or presence of immature anopheline mosquitoes (larvae and pupae forms) in water sources to determine whether this intervention has any potential that may justify further research in the control of malaria vectors. Data collection and analysis Two review authors independently screened each article by title and abstract, and examined potentially relevant studies for inclusion using an eligibility form. At least two review authors independently extracted data and assessed risk of bias of included studies. If relevant data were unclear or were not reported, we contacted the study authors for clarification. We presented data in tables, and we summarized studies that evaluated the effects of introducing fish on anopheline immature density or presence, or both. We used the GRADE approach to summarize the certainty of the evidence. We also examined whether the included studies reported any possible adverse impact of introducing larvivorous fish on non-target native species. Main results We identified no studies that reported the effects of introducing larvivorous fish on the primary outcomes of this review: malaria infection in nearby communities, entomological inoculation rate, or on adult Anopheles density. For the secondary analysis, we examined the effects of introducing larvivorous fish on the density and presence of anopheline larvae and pupae in community water sources, and found 15 small studies with a follow-up period between 22 days and five years. These studies were undertaken in Sri Lanka (two studies), India (three studies), Ethiopia (one study), Kenya (two studies), Sudan (one study), Grande Comore Island (one study), Korea (two studies), Indonesia (one study), and Tajikistan (two studies). These studies were conducted in a variety of settings, including localized water bodies (such as wells, domestic water containers, fishponds, and pools (seven studies); riverbed pools below dams (two studies)); rice field plots (five studies); and water canals (two studies). All included studies were at high risk of bias. The research was insufficient to determine whether larvivorous fish reduce the density of Anopheles larvae and pupae (12 studies, unpooled data, very low certainty evidence). Some studies with high stocking levels of fish seemed to arrest the increase in immature anopheline populations, or to reduce the number of immature anopheline mosquitoes, compared with controls. However, this finding was not consistent, and in studies that showed a decrease in immature anopheline populations, the effect was not always consistently sustained. In contrast, some studies reported larvivorous fish reduced the number of water sources withAnopheles larvae and pupae (five studies, unpooled data, low certainty evidence). None of the included studies reported effects of larvivorous fish on local native fish populations or other species. Authors' conclusions We do not know whether introducing larvivorous fish reduces malaria transmission or the density of adult anopheline mosquito populations. In research studies that examined the effects on immature anopheline stages of introducing fish to potential malaria vector larval habitats, high stocking levels of fish may reduce the density or presence of immature anopheline mosquitoes in the short term. We do not know whether this translates into impact on malaria transmission. Our interpretation of the current evidence is that countries should not invest in fish stocking as a stand alone or supplementary larval control measure in any malaria transmission areas outside the context of research using carefully controlled field studies or quasi-experimental designs. Such research should examine the effects on native fish and other non-target species. Fish that feed on mosquito larvae for preventing malaria transmission What is the aim of this review? Adult female Anopheles mosquitoes transmit the Plasmodium parasites that cause malaria. The aim of this Cochrane Review was to evaluate whether introducing fish that eat mosquito larvae and pupae (early life stages of mosquitoes) into water sources near where people live will decrease the adult Anopheles mosquito population and thus the number of people infected with Plasmodium parasites. Key messages We do not know if introducing fish that eat mosquito larvae and pupae has an impact on the number of people with malaria or on the adult Anopheles mosquito population. What was studied in the review? The review authors examined the available research that evaluated introducing fish that eat larvae ('larvivorous') to Anopheles mosquito larval habitats in areas where malaria was common. Fifteen small studies looked at the effects of larvivorous fish on Anopheles larvae and pupae in different larval habitats, including localized water bodies (such as wells, domestic water containers, fishponds, and pools; seven studies), riverbed pools below dams (two studies), rice field plots (four studies), and water canals (two studies). These studies were undertaken in Sri Lanka (two studies), India (three studies), Ethiopia (one study), Kenya (two studies), Sudan (one study), Grande Comore Island (one study), Korea (two studies), Indonesia (one study), and Tajikistan (two studies). This is an update of a 2013 Cochrane Review and includes some older unpublished studies from Tajikistan and a new trial from India. What are the main results of the review? In our main analysis, we found no studies that looked at the effects of larvivorous fish on adult Anopheles mosquito populations or on the number of people infected with Plasmodium parasites. In our analysis exploring the effect of fish introduction on the number of Anopheles larvae and pupae in water collections, these studies produced inconsistent results on immature mosquito density (12 studies, unpooled data, very low certainty evidence). Some studies that measured the number of water sources withAnopheles larvae and pupae reported a reduction in the number of sites with Anopheles larvae and pupae after introducing fish (five studies, unpooled data, low certainty evidence). None of the included studies examined the effects of introducing larvivorous fish on other native species present, but these studies were not designed to do this. All included studies were at high risk of bias. Before much is invested in this intervention, we need better research to determine the effect of introducing larvivorous fish on the number of people infected with malaria, and on adult Anopheles populations. Researchers need to use robust controlled designs with an adequate number of sites. In addition, researchers should explore the potential harms from introducing these fish on native fish and other non-Anopheles species. How up-to-date is this review? The review authors searched for studies published up to 6 July 2017. PMID:29226959
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martin, D.
2007-03-05
Altering flow regimes of rivers has large effects on native floras and faunas because native species are adapted to the natural flow regime, many species require lateral connectivity with floodplain habitat for feeding or spawning, and the change in regime often makes it possible for invasive species to replace natives (Bunn & Arthington 2002). Floodplain backwaters, both permanent and temporary, are nursery areas for age 0+ fish and stable isotope studies indicate that much of the productivity that supports fish larvae is autochthonous to these habitats (Herwig et al. 2004). Limiting access by fish to floodplain habitat for feeding, spawningmore » and nursery habitat is one of the problems noted with dams that regulate flow in rivers and is considered to be important as an argument to remove dams and other flow regulating structures from rivers (Shuman 1995; Bednarek 2001). While there have been a number of studies in the literature about the use of floodplain habitat for fish reproduction (Copp 1989; Killgore & Baker 1996; Humphries, et al. 1999; Humphries and Lake 2000; Crain et al. 2004; King 2004) there have been only a few studies that examined this aspect of stream ecology in more than a cursory way. The study reported here was originally designed to determine whether the Department of Energy's (DOE) Savannah River Site was having a negative effect on fish reproduction in the Savannah River but its experimental design allowed examination of the interactions between the river, the floodplain and the tributaries entering the Savannah River across this floodplain. This study is larger in length of river covered than most in the literature and because of its landscape scale may be in important indicator of areas where further study is required.« less
Population characteristics and the influence of discharge on Bluehead Sucker and Flannelmouth Sucker
Klein, Zachary B.; Breen, Matthew J.; Quist, Michael C.
2017-01-01
Rivers are among some of the most complex and important ecosystems in the world. Unfortunately, many fishes endemic to rivers have suffered declines in abundance and distribution suggesting that alterations to lotic environments have negatively influenced native fish populations. Of the 35 fishes native to the Colorado River basin (CRB), seven are considered either endangered, threatened, or species of special concern. As such, the conservation of fishes native to the CRB is a primary interest for natural resource management agencies. One of the major factors limiting the conservation and management of fishes endemic to the CRB is the lack of basic information on their ecology and population characteristics. We sought to describe the population dynamics and demographics of three populations of Bluehead Suckers (Catostomus discobolus) and Flannelmouth Suckers (C. latipinnis) in Utah. Additionally, we evaluated the potential influence of altered flow regimes on the recruitment and growth of Bluehead Suckers and Flannelmouth Suckers. Mortality of Bluehead Suckers and Flannelmouth Suckers from the Green, Strawberry, and White rivers was comparable to other populations. Growth of Bluehead Suckers and Flannelmouth Suckers was higher in the Green, Strawberry, and White rivers when compared to other populations in the CRB. Similarly, recruitment indices suggested that Bluehead Suckers and Flannelmouth Suckers in the Green, Strawberry, and White rivers had more stable recruitment than other populations in the CRB. Models relating growth and recruitment to hydrological indices provided little explanatory power. Notwithstanding, our results indicate that Bluehead Suckers and Flannelmouth Suckers in the Green, Strawberry, and White rivers represent fairly stable populations and provide baseline information that will be valuable for the effective management and conservation of the species.
Fish stocking in protected areas: summary of a workshop
Paul Stephen Corn; Roland A. Knapp
2000-01-01
Native and nonnative sport fish have been introduced into the majority of historically fishless lakes in wilderness, generating conflicts between managing wilderness as natural ecosystems and providing opportunities for recreation. Managers faced with controversial and difficult decisions about how to manage wilderness lakes may not always have ready access to research...
Exploring Fish Diversity as a Determinant of Ecosystem Properties in Aquatic Food Webs
ERIC Educational Resources Information Center
Carey, Michael P.
2009-01-01
Dramatic biodiversity changes occurring globally from species loss and invasion have altered native food webs and ecosystem processes. My research objectives are to understand the consequences of fish diversity to freshwater systems by (1) examining the food web consequences of multiple top predators, (2) determining how biodiversity influences…
Centrarchid identification and natural history
M.L. Warren
2009-01-01
The family Centrarchidae (Order: Perciformes) is one of the most diverse, widespread, and conspicuous fish families native to freshwater habitats of North America. Among endemic fish families of North America, only the North American catfish family (Ictaluridae) has more species. The family name, Centrarchidae, refers to the anal fin spines of species in the family,...
Adaptation to wildfire: A fish story
John Kirkland; Rebecca Flitcroft; Gordon Reeves; Paul Hessburg
2017-01-01
In the Pacific Northwest, native salmon and trout are some of the toughest survivors on the block. Over time, these fish have evolved behavioral adaptations to natural disturbances, and they rely on these disturbances to deliver coarse sediment and wood that become complex stream habitat. Powerful disturbances such as wildfire, postfire landslides, and debris flows may...
Historical and pictorial perspective of the Upper Verde River [Chapter 2
Alvin L. Medina; Daniel G. Neary
2012-01-01
The UVR corridor is a diverse riverine ecosystem in central Arizona (see Chapter 1). Since European settlement, it has witnessed many events such as droughts, floods, construction of Sullivan Dam, groundwater withdrawals, cattle grazing, mining, nonnative fish introductions, native fish extinctions, and urbanization that are not fully understood. Geologically, the UVR...
Native Wellness Department: Wilbert Fish Cultivates Blackfeet Traditions of Healing.
ERIC Educational Resources Information Center
Johnson, Lester R. III
2002-01-01
Describes the Greenhouse Project, a joint effort to reintroduce medicinal plants to the Blackfeet Indian population in Montana. Reports that Wilbert Fish, son of a prominent tribal healer, and his staff produce more than 5,000 species of plants, both for medicinal purposes and for restoration projects in Glacier National Park. (NB)
NASA Astrophysics Data System (ADS)
Jain, S.; Topping, D. J.; Melis, T. S.
2014-12-01
Planning and decision processes in the Glen Canyon Dam Adaptive Management Program (GCDAMP) strive to balance numerous, often competing, objectives, such as, water supply, hydropower generation, low flow maintenance, sandbars, recreational trout angling, endangered native fish, whitewater rafting, and other sociocultural resources of Glen Canyon National Recreation Area and Grand Canyon National Park. In this context, use of monitored and predictive information on warm-season Paria River floods (JUL-OCT, at point-to-regional scales) has been identified as lead information for a new 10-year long controlled flooding experiment (termed the High-Flow Experiment Protocol) intended to determine management options for rebuilding and maintaining sandbars below Glen Canyon Dam; an adaptive strategy that can potentially facilitate improved planning and dam operations. In this work, we focus on a key concern identified by the GCDAMP, related to the timing and volume of warm season tributary sand input from the Paria River into the Colorado River in Grand Canyon National Park. The Little Colorado River is an important secondary source of sand inputs to Grand Canyon, but its lower segment is also critical spawning habitat for the endangered humpback chub. Fish biologists have reported increased abundance of chub juveniles in this key tributary in summers following cool-season flooding (DEC-FEB), but little is known about chub spawning substrates and behavior or the role that flood frequency in this tributary may play in native fish population dynamics in Grand Canyon. Episodic and intraseasonal variations (with links to equatorial and sub-tropical Pacific sea surface temperature variability) in southwest hydroclimatology are investigated to understand the magnitude, timing and spatial scales of warm- and cool-season floods from these two important tributaries of the semi-arid Colorado Plateau. Coupled variations of floods (magnitude and timing) from these rivers are also investigated. The physical processes, including diagnosis of storms and moisture sources, are mapped alongside the planning and decision processes for the ongoing experimental flood releases from the dam which are aimed at improving sandbars and instream ecology of native fish.
Hansen, Michael J.; Hansen, Barry S; Beauchamp, David A.
2016-01-01
Non-native lake trout Salvelinus namaycush displaced native bull trout Salvelinus confluentus in Flathead Lake, Montana, USA, after 1984, when Mysis diluviana became abundant following its introduction in upstream lakes in 1968–1976. We developed a simulation model to determine the fishing mortality rate on lake trout that would enable bull trout recovery. Model simulations indicated that suppression of adult lake trout by 75% from current abundance would reduce predation on bull trout by 90%. Current removals of lake trout through incentivized fishing contests has not been sufficient to suppress lake trout abundance estimated by mark-recapture or indexed by stratified-random gill netting. In contrast, size structure, body condition, mortality, and maturity are changing consistent with a density-dependent reduction in lake trout abundance. Population modeling indicated total fishing effort would need to increase 3-fold to reduce adult lake trout population density by 75%. We conclude that increased fishing effort would suppress lake trout population density and predation on juvenile bull trout, and thereby enable higher abundance of adult bull trout in Flathead Lake and its tributaries.
R, Jini; HC, Swapna; Rai, Amit Kumar; R, Vrinda; PM, Halami; NM, Sachindra; N, Bhaskar
2011-01-01
Proteolytic and/or lipolytic lactic acid bacteria (LAB) were isolated from visceral wastes of different fresh water fishes. LAB count was found to be highest in case of visceral wastes of Mrigal (5.88 log cfu/g) and lowest in that of tilapia (4.22 log cfu/g). Morphological, biochemical and molecular characterization of the selected LAB isolates were carried out. Two isolates FJ1 (E. faecalis NCIM5367) and LP3 (P. acidilactici NCIM5368) showed both proteolytic and lipolytic properties. All the six native isolates selected for characterization showed antagonistic properties against several human pathogens. All the native isolates were sensitive to antibiotics cephalothin and clindamycin; and, resistant to cotrimoxazole and vancomycin. Considering individually, P. acidilactici FM37, P. acidilactici MW2 and E. faecalis FD3 were sensitive to erythromycin. The two strains FJ1 (E. faecalis NCIM 5367) and LP3 (P. acidilactici NCIM 5368) that had both proteolytic and lipolytic properties have the potential for application in fermentative recovery of lipids and proteins from fish processing wastes. PMID:24031786
Historical changes in Nebraska's lotic fish assemblages: Implications of anthropogenic alterations
Smith, Christopher D.; Fischer, Jesse R.; Quist, Michael C.
2014-01-01
The plains of midwestern North America have undergone significant anthropogenic alterations following European settlement with consequent effects to lotic fish assemblage structure. We examined trends in fish assemblage structure and function in Nebraska's lotic systems using site-specific, presence-absence data from historical (1939–1940) and contemporary surveys (2003–2005; n = 183). Shifts in fish assemblage structure were characterized by declines of specialist species (e.g., western silvery minnow Hybognathus argyritis) and increases in nonnative, sport, and generalist species (e.g., common carp Cyprinus carpio). Our research illustrates differences between historical and contemporary surveys for both taxonomic and functional metrics. Changes in fish assemblage structure were correlated with a contemporary measure of anthropogenic alteration (Human Threat Index; HTI) and were most pronounced for large-scale threats (i.e., watershed HTI, overall HTI). The HTI is a composite index of cumulative anthropogenic alterations experienced by a stream system and was used to investigate broad-scale implications of anthropogenic activity on fish assemblage structure. Fish assemblages among sites were more similar in contemporary surveys than in historical surveys, such changes might indicate a homogenization of the fish assemblages. Losses of native species and increases in introduced species have occurred in Nebraska's lotic systems across a broad temporal span and shifts are likely related to high levels of human perturbation.
Ross, Rob; Grams, Paul E.
2013-01-01
Construction and operation of Glen Canyon Dam has dramatically impacted the flow of the Colorado River through Glen, Marble, and Grand Canyons. Extremes in both streamflow and water temperature have been suppressed by controlled releases from the dam. Trapping of sediment in Lake Powell, the reservoir formed by Glen Canyon Dam, has also dramatically reduced the supply of suspended sediment entering the system. These changes have altered the riverine ecosystem and the habitat of native species, including fish such as the endangered humpback chub (Gila cypha). Most native fish are adapted to seasonally warm water, and the continuous relatively cold water released by the dam is one of the factors that is believed to limit humpback chub growth and survival. While average mainstem temperatures in the Colorado River are well documented, there is limited understanding of temperatures in the nearshore environments that fish typically occupy. Four nearshore geomorphic unit types were studied between the confluence of the Colorado and Little Colorado Rivers and Lava Canyon in the summer and fall of 2010, for study periods of 10 to 27 days. Five to seven sites were studied during each interval. Persistent thermal gradients greater than the 0.2 °C accuracy of the instruments were not observed in any of the sampled shoreline environments. Temperature gradients between the shoreline and mainstem on the order of 4 °C, believed to be important to the habitat-seeking behavior of native or nonnative fishes, were not detected.
Gianni, Fabrizio; Bartolini, Fabrizio; Airoldi, Laura; Mangialajo, Luisa
2018-07-01
Coastal areas have been transformed worldwide by urbanization, so that artificial structures are now widespread. Current coastal development locally depletes many native marine species, while offering limited possibilities for their expansion. Eco-engineering interventions intend to identify ways to facilitate the presence of focal species and their associated functions on artificial habitats. An important but overlooked factor controlling restoration operations is overgrazing by herbivores. The aim of this study was to quantify the effects of different potential feeders on Cystoseira amentacea, a native canopy-forming alga of the Mediterranean infralittoral fringe, and test whether manipulation of grazing pressure can facilitate the human-guided installation of this focal species on coastal structures. Results of laboratory tests and field experiments revealed that Sarpa salpa, the only strictly native herbivorous fish in the Western Mediterranean Sea, can be a very effective grazer of C. amentacea in artificial habitats, up to as far as the infralittoral fringe, which is generally considered less accessible to fishes. S. salpa can limit the success of forestation operations in artificial novel habitats, causing up to 90% of Cystoseira loss after a few days. Other grazers, such as limpets and crabs, had only a moderate impact. Future engineering operations,intended to perform forestation of canopy-forming algae on artificial structures, should consider relevant biotic factors, such as fish overgrazing, identifying cost-effective techniques to limit their impact, as is the usual practice in restoration programmes on land. Copyright © 2018 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
The Sensor Fish collects information that can be used to evaluate conditions encountered by juvenile salmonids and other fish as they pass through hydroelectric dams on their way to the ocean. Sensor Fish are deployed in turbines, spillways, and sluiceways and measure changes in pressure, angular rate of change, and linear acceleration during passage. The software is need to make Sensor Fish fully functional and easy to use. Sensor Fish Communicator (SFC) links to Sensor Fish, allowing users to control data collection settings and download data. It may also be used to convert native raw data (.raw2) files into Commamore » Separated Variable (.csv) files and plot the results. The multiple capabilities of the SFC allow hardware communication, data conversion, and data plotting with one application.« less
Invasion patterns along elevation and urbanization gradients in Hawaiian streams
Brasher, A.M.D.; Luton, C.D.; Goodbred, S.L.; Wolff, R.H.
2006-01-01
Hawaii's extreme isolation has resulted in a native stream fauna characterized by high endemism and unusual life history characteristics. With the rapid increase in the human population, the viability of Hawaiian stream ecosystems is threatened by development and the associated habitat alteration. Thirty-eight sites on three islands (Oahu, Kauai, and Hawaii) were sampled to determine how habitat alteration resulting from urbanization and development was associated with the establishment of introduced species. Undeveloped sites had higher streamflow velocities, more riffles, lower embeddedness, deeper water, larger substrate, and lower water temperature than developed sites. Developed sites additionally had more pools and greater sparseness of riparian canopy cover. Overall, 23 fish species from 11 families and 5 crustacean species from 3 families were collected. Of these, 16 fish species and 3 crustacean species were introduced. Developed sites had on average almost twice as many species as undeveloped sites and were dominated by introduced species. Low-elevation sites were the most developed and supported the highest number of introduced species. However, species composition at some relatively undeveloped sites was impacted by downstream habitat alteration, since all native species must pass through the lower reaches to complete their life cycles. With increasing urbanization and development, the habitat features required by native species are disappearing and streams are becoming more suitable for generalist introduced species, which are typically better adapted for altered habitats than are native species. As development pressures in tropical island ecosystems increase worldwide, this will become an increasingly important issue globally. An understanding of which habitats are most likely to support nonnative species provides information necessary for developing a management strategy to protect aquatic ecosystems from invasive nonnative species.
Sustainability of the Lake Superior fish community: Interactions in a food web context
Kitchell, James F.; Cox, Sean P.; Harvey, Chris J.; Johnson, Timothy B.; Mason, Doran M.; Schoen, Kurt K.; Aydin, Kerim; Bronte, Charles; Ebener, Mark; Hansen, Michael; Hoff, Michael; Schram, Steve; Schreiner, Don; Walters, Carl J.
2000-01-01
The restoration and rehabilitation of the native fish communities is a long-term goal for the Laurentian Great Lakes. In Lake Superior, the ongoing restoration of the native lake trout populations is now regarded as one of the major success stories in fisheries management. However, populations of the deepwater morphotype (siscowet lake trout) have increased much more substantially than those of the nearshore morphotype (lean lake trout), and the ecosystem now contains an assemblage of exotic species such as sea lamprey, rainbow smelt, and Pacific salmon (chinook, coho, and steelhead). Those species play an important role in defining the constraints and opportunities for ecosystem management. We combined an equilibrium mass balance model (Ecopath) with a dynamic food web model (Ecosim) to evaluate the ecological consequences of future alternative management strategies and the interaction of two different sets of life history characteristics for fishes at the top of the food web. Relatively rapid turnover rates occur among the exotic forage fish, rainbow smelt, and its primary predators, exotic Pacific salmonids. Slower turnover rates occur among the native lake trout and burbot and their primary prey—lake herring, smelt, deepwater cisco, and sculpins. The abundance of forage fish is a key constraint for all salmonids in Lake Superior. Smelt and Mysis play a prominent role in sustaining the current trophic structure. Competition between the native lake trout and the exotic salmonids is asymmetric. Reductions in the salmon population yield only a modest benefit for the stocks of lake trout, whereas increased fishing of lake trout produces substantial potential increases in the yields of Pacific salmon to recreational fisheries. The deepwater or siscowet morphotype of lake trout has become very abundant. Although it plays a major role in the structure of the food web it offers little potential for the restoration of a valuable commercial or recreational fishery. Even if a combination of strong management actions is implemented, the populations of lean (nearshore) lake trout cannot be restored to pre-fishery and pre-lamprey levels. Thus, management strategy must accept the ecological constraints due in part to the presence of exotics and choose alternatives that sustain public interest in the resources while continuing the gradual progress toward restoration.
Limitation and facilitation of one of the world's most invasive fish: an intercontinental comparison
Budy, Phaedra E.; Thiede, Gary P.; Lobón-Cerviá, Javier; Fernandez, Gustavo Gonzolez; McHugh, Peter; McIntosh, Angus; Vøllestad, Lief Asbjørn; Becares, Eloy; Jellyman, Phillip
2013-01-01
Purposeful species introductions offer opportunities to inform our understanding of both invasion success and conservation hurdles. We evaluated factors determining the energetic limitations of brown trout (Salmo trutta) in both their native and introduced ranges. Our focus was on brown trout because they are nearly globally distributed, considered one of the world's worst invaders, yet imperiled in much of their native habitat. We synthesized and compared data describing temperature regime, diet, growth, and maximum body size across multiple spatial and temporal scales, from country (both exotic and native habitats) and major geographic area (MGA) to rivers and years within MGA. Using these data as inputs, we next used bioenergetic efficiency (BioEff), a relative scalar representing a realized percentage of maximum possible consumption (0–100%) as our primary response variable and a multi-scale, nested, mixed statistical model (GLIMMIX) to evaluate variation among and within spatial scales and as a function of density and elevation. MGA and year (the residual) explained the greatest proportion of variance in BioEff. Temperature varied widely among MGA and was a strong driver of variation in BioEff. We observed surprisingly little variation in the diet of brown trout, except the overwhelming influence of the switch to piscivory observed only in exotic MGA. We observed only a weak signal of density-dependent effects on BioEff; however, BioEff remained 2.5 fish/m2. The trajectory of BioEff across the life span of the fish elucidated the substantial variation in performance among MGAs; the maximum body size attained by brown trout was consistently below 400 mm in native habitat but reached 600 mm outside their native range, where brown trout grew rapidly, feeding in part on naive prey fishes. The integrative, physiological approach, in combination with the intercontinental and comparative nature of our study, allowed us to overcome challenges associated with context-dependent variation in determining invasion success. Overall our results indicate “growth plasticity across the life span” was important for facilitating invasion, and should be added to lists of factors characterizing successful invaders.
Catchment-scale determinants of nonindigenous minnow richness in the eastern United States
Peoples, Brandon K.; Midway, Stephen R.; DeWeber, Jefferson T.; Wagner, Tyler
2018-01-01
Understanding the drivers of biological invasions is critical for preserving aquatic biodiversity. Stream fishes make excellent model taxa for examining mechanisms driving species introduction success because their distributions are naturally limited by catchment boundaries. In this study, we compared the relative importance of catchment-scale abiotic and biotic predictors of native and nonindigenous minnow (Cyprinidae) richness in 170 catchments throughout the eastern United States. We compared historic and contemporary cyprinid distributional data to determine catchment-wise native/nonindigenous status for 152 species. Catchment-scale model predictor variables described natural (elevation, precipitation, flow accumulation) and anthropogenic (developed land cover, number of dams) abiotic features, as well as native congener richness. Native congener richness may represent either biotic resistance via interspecific competition, or trait preadaptation according to Darwin's naturalisation hypothesis. We used generalised linear mixed models to examine evidence supporting the relative roles of abiotic and biotic predictors of cyprinid introduction success. Native congener richness was positively correlated with nonindigenous cyprinid richness and was the most important variable predicting nonindigenous cyprinid richness. Mean elevation had a weak positive effect, and effects of other abiotic factors were insignificant and less important. Our results suggest that at this spatial scale, trait preadaptation may be more important than intrageneric competition for determining richness of nonindigenous fishes.
A synthesis of ecological and fish-community changes in Lake Ontario, 1970-2000
Mills, E.L.; Casselman, J.M.; Dermott, R.; Fitzsimons, J.D.; Gal, G.; Holeck, K. T.; Hoyle, J.A.; Johannsson, O.E.; Lantry, B.F.; Makarewicz, J.C.; Millard, E.S.; Munawar, I.F.; Munawar, M.; O'Gorman, R.; Owens, R.W.; Rudstam, L. G.; Schaner, T.; Stewart, T.J.
2005-01-01
We assessed stressors associated with ecological and fishcommunity changes in Lake Ontario since 1970, when the first symposium on Salmonid Communities in Oligotrophic Lakes (SCOL I) was held (J. Fish. Res. Board Can. 29: 613-616). Phosphorus controls implemented in the early 1970s were undeniably successful; lower food-web studies showed declines in algal abundance and epilimnetic zooplankton production and a shift in pelagic primary productivity toward smaller organisms. Stressors on the fish community prior to 1970 such as exploitation, sea lamprey (Petromyzon marinus) predation, and effects of nuisance populations of alewife (Alosa pseudoharengus) were largely ameliorated by the 1990s. The alewife became a pivotal species supporting a multi-million-dollar salmonid sport fishery, but alewife-induced thiamine deficiency continued to hamper restoration and sustainability of native lake trout (Salvelinus namaycush). Expanding salmonine populations dependent on alewife raised concerns about predator demand and prey supply, leading to reductions in salmonine stocking in the early 1990s. Relaxation of the predation impact by alewives and their shift to deeper water allowed recovery of native fishes such as threespine stickleback (Gasterosteus aculeatus) and emerald shiner (Notropis atherinoides). The return of the Lake Ontario ecosystem to historical conditions has been impeded by unplanned introductions. Establishment of Dreissena spp. led to increased water clarity and increased vectoring of lower trophic-level production to benthic habitats and contributed to the collapse of Diporeia spp. populations, behavioral modifications of key fish species, and the decline of native lake whitefish (Coregonus clupeaformis). Despite reduced productivity, exotic-species introductions, and changes in the fish community, offshore Mysis relicta populations remained relatively stable. The effects of climate and climate change on the population abundance and dynamics of Lake Ontario fish were unknown at the time of SCOL I, but a temperature-time series begun in the late 1950s in the Kingston Basin has since provided evidence of climate warming and associated fish-community changes. We should expect ecological surprises in the coming decades that will challenge scientists and fishery managers especially as they face new exotic species, climate warming, and escalating stakeholder demands on the resource. Continuous long-term ecological studies were critical for interpreting changes in Lake Ontario's fish community over the past three decades and will be essential in the future for both scientific understanding and management of the fishery.
Chapter 5. Plant gathering, game hunting, fishing, mineral collecting, and agriculture
Kurt F. Anschuetz
2007-01-01
Native American populations have cut wood for shelters and fuel, gathered native plants, hunted game animals, and collected various other resources, such as obsidian for making chipped-stone tools, clay for crafting pottery vessels, and stone slabs for producing piki (corn meal paper bread) griddles, in the Valles Caldera National Preserve (VCNP) for countless...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-08
... Registration of Certain Dead Marine Mammal Hard Parts AGENCY: Fish and Wildlife Service, Interior. ACTION... Form 3-2406 (Registration of Certain Dead Marine Mammal Hard Parts) to record the collection of bones, teeth, or ivory of dead marine mammals by non-Native and Natives not eligible to harvest marine mammals...
The Prairie Science Class: Pioneering a Trail in Interdisciplinary Learning
ERIC Educational Resources Information Center
Ernst, Julie; Ellis, Dave
2005-01-01
What happens when an old farmstead, native tall-grass prairie, and middle school students are mixed together? Would one guess learning? That is exactly what is happening in Fergus Falls, Minnesota, where students from a rural middle school have joined with the U.S. Fish and Wildlife Service (USFWS) to restore native tallgrass prairie. In the…
Liza R. Walleser,; D.R. Howard,; Sandheinrich, Mark B.; Gaikowski, Mark P.; Amberg, Jon J.
2014-01-01
To better understand potential diet overlap among exotic Asian species of carp and native species of filter-feeding fishes of the upper Mississippi River system, microscopy was used to document morphological differences in the gill rakers. Analysing samples first with light microscopy and subsequently with confocal microscopy, the three-dimensional structure of gill rakers in Hypophthalmichthys molitrix,Hypophthalmichthys nobilis and Dorosoma cepedianum was more thoroughly described and illustrated than previous work with traditional microscopy techniques. The three-dimensional structure of gill rakers in Ictiobus cyprinellus was described and illustrated for the first time.
Saunders, W. Carl; Budy, Phaedra E.; Thiede, Gary P.
2015-01-01
Exotic species present a great threat to native fish conservation; however, eradicating exotics is expensive and often impractical. Mechanical removal can be ineffective for eradication, but nonetheless may increase management effectiveness by identifying portions of a watershed that are strong sources of exotics. We used mechanical removal to understand processes driving exotic brown trout (Salmo trutta) populations in the Logan River, Utah. Our goals were to: (i) evaluate the demographic response of brown trout to mechanical removal, (ii) identify sources of brown trout recruitment at a watershed scale and (iii) evaluate whether mechanical removal can reduce brown trout densities. We removed brown trout from 2 km of the Logan River (4174 fish), and 5.6 km of Right Hand Fork (RHF, 15,245 fish), a low-elevation tributary, using single-pass electrofishing. We compared fish abundance and size distributions prior to, and after 2 years of mechanical removal. In the Logan River, immigration to the removal reach and high natural variability in fish abundances limited the response to mechanical removal. In contrast, mechanical removal in RHF resulted in a strong recruitment pulse, shifting the size distribution towards smaller fish. These results suggest that, before removal, density-dependent mortality or emigration of juvenile fish stabilised adult populations and may have provided a source of juveniles to the main stem. Overall, in sites demonstrating strong density-dependent population regulation, or near sources of exotics, short-term mechanical removal has limited effects on brown trout populations but may help identify factors governing populations and inform large-scale management of exotic species.
Status and trends of pelagic prey fishes in Lake Huron, 2012
Warner, David M.; O'Brien, Timothy P.; Farha, Steve A.; Schaeffer, Jeff; Lenart, Stephen
2012-01-01
The USGS Great Lakes Science Center (GLSC) conducted acoustic/midwater trawl surveys of Lake Huron during 1997 and annually during 2004-2012. The 2012 survey was conducted during September and October, and included transects in Lake Huron’s Main Basin, Georgian Bay, and North Channel. Pelagic fish density (638 fish/ha) was lower in 2012 compared to 2011, with density in 2012 only 34% of 2011. Total biomass in 2012 was 74% of the 2011 value. Alewife Alosa pseudoharengus remained nearly absent, and only one cisco Coregonus artedi was captured. Rainbow smelt Osmerus mordax density was only 31% of the 2011 density. Bloater Coregonus hoyi density was less than half the 2011 density, mostly as a result of lower density of small bloater. Density and biomass of large bloater in 2012 were similar to 2011 levels. During 2012 we observed significantly higher fish biomass in North Channel than in the Main Basin or Georgian Bay. Prey availability during 2013 will likely be similar to 2012. Lake Huron now has pelagic fish biomass similar to that observed in recent lakewide acoustic surveys of Lake Michigan and Lake Superior, but species composition differs in the three lakes. There is an increasing diversity and prevalence of native species gradient from Lake Michigan to Lake Superior, with Lake Huron being intermediate in the prevalence of native fish species like coregonines and emerald shiner Notropis atherinoides.
Status and trends of pelagic prey fishes in Lake Huron, 2012
Warner, David M.; O'Brien, Timothy P.; Farha, Steve A.; Schaeffer, Jeff; Lenart, Stephen
2013-01-01
The USGS Great Lakes Science Center (GLSC) conducted acoustic/midwater trawl surveys of Lake Huron during 1997 and annually during 2004-2012. The 2012 survey was conducted during September and October, and included transects in Lake Huron’s Main Basin, Georgian Bay, and North Channel. Pelagic fish density (638 fish/ha) was lower in 2012 compared to 2011, with density in 2012 only 34% of 2011. Total biomass in 2012 was 74% of the 2011 value. Alewife Alosa pseudoharengus remained nearly absent, and only one cisco Coregonus artedi was captured. Rainbow smelt Osmerus mordax density was only 31% of the 2011 density. Bloater Coregonus hoyi density was less than half the 2011 density, mostly as a result of lower density of small bloater. Density and biomass of large bloater in 2012 were similar to 2011 levels. During 2012 we observed significantly higher fish biomass in North Channel than in the Main Basin or Georgian Bay. Prey availability during 2013 will likely be similar to 2012. Lake Huron now has pelagic fish biomass similar to that observed in recent lakewide acoustic surveys of Lake Michigan and Lake Superior, but species composition differs in the three lakes. There is an increasing diversity and prevalence of native species gradient from Lake Michigan to Lake Superior, with Lake Huron being intermediate in the prevalence of native fish species like coregonines and emerald shiner Notropis atherinoides.
Whittington, R J; Chong, R
2007-09-14
Over 1 billion ornamental fish comprising more than 4000 freshwater and 1400 marine species are traded internationally each year, with 8-10 million imported into Australia alone. Compared to other commodities, the pathogens and disease translocation risks associated with this pattern of trade have been poorly documented. The aim of this study was to conduct an appraisal of the effectiveness of risk analysis and quarantine controls as they are applied according to the Sanitary and Phytosanitary (SPS) agreement in Australia. Ornamental fish originate from about 100 countries and hazards are mostly unknown; since 2000 there have been 16-fold fewer scientific publications on ornamental fish disease compared to farmed fish disease, and 470 fewer compared to disease in terrestrial species (cattle). The import quarantine policies of a range of countries were reviewed and classified as stringent or non-stringent based on the levels of pre-border and border controls. Australia has a stringent policy which includes pre-border health certification and a mandatory quarantine period at border of 1-3 weeks in registered quarantine premises supervised by government quarantine staff. Despite these measures there have been many disease incursions as well as establishment of significant exotic viral, bacterial, fungal, protozoal and metazoan pathogens from ornamental fish in farmed native Australian fish and free-living introduced species. Recent examples include Megalocytivirus and Aeromonas salmonicida atypical strain. In 2006, there were 22 species of alien ornamental fish with established breeding populations in waterways in Australia and freshwater plants and molluscs have also been introduced, proving a direct transmission pathway for establishment of pathogens in native fish species. Australia's stringent quarantine policies for imported ornamental fish are based on import risk analysis under the SPS agreement but have not provided an acceptable level of protection (ALOP) consistent with government objectives to prevent introduction of pests and diseases, promote development of future aquaculture industries or maintain biodiversity. It is concluded that the risk analysis process described by the Office International des Epizooties under the SPS agreement cannot be used in a meaningful way for current patterns of ornamental fish trade. Transboundary disease incursions will continue and exotic pathogens will become established in new regions as a result of the ornamental fish trade, and this will be an international phenomenon. Ornamental fish represent a special case in live animal trade where OIE guidelines for risk analysis need to be revised. Alternatively, for countries such as Australia with implied very high ALOP, the number of species traded and the number of sources permitted need to be dramatically reduced to facilitate hazard identification, risk assessment and import quarantine controls.
Gadomski, D.M.; Barfoot, C.A.
1998-01-01
Diel and distributional abundance patterns of free embryos and larvae of fishes in the lower Columbia River Basin were investigated. Ichthyoplankton samples were collected in 1993 during day and night in the main-channel and a backwater of the lower Columbia River, and in a tributary, the Deschutes River. Fish embryos and larvae collected in the main-channel Columbia River were primarily (85.6%) of native taxa (peamouth Mylocheilus caurinus, northern squawfish Ptychocheilus oregonensis, suckers Catostomus spp., and sculpins Cottus spp.), with two introduced species (American shad Alosa sapidissima and common carp Cyprinus carpio) comprising a smaller percentage of the catch (13.3%). Similarly, in the Deschutes River native taxa [lampreys (Petromyzontidae), minnows (Cyprinidae), and suckers Catostomus spp.] dominated collections (99.5% of the catch). In contrast, 83.5% of embryos and larvae in the Columbia River backwater were of introduced taxa [American shad, common carp, and sunfishes (Centrarchidae)]. In all locations, all dominant taxa except sculpins were collected in significantly greater proportions at night. Taxon-specific differences in proportions of embryos and larvae collected at night can in some instances be related to life history styles. In the main-channel Columbia River, northern squawfish and peamouth were strongly nocturnal and high proportions still had yolksacs, suggesting that they had recently hatched and were drifting downriver to rearing areas. In contrast, sculpin abundances were similar during day and night, and sculpins mostly had depleted yolksacs, indicating sculpins were feeding and rearing in offshore limnetic habitats. Taxon-specific diel abundance patterns and their causes must be considered when designing effective sampling programs for fish embryos and larvae.
Longitudinal differences in habitat complexity and fish assemblage structure of a great plains river
Eitzmann, J.L.; Paukert, C.P.
2010-01-01
We investigated the spatial variation in the Kansas River (USA) fish assemblage to determine how fish community structure changes with habitat complexity in a large river. Fishes were collected at ten sites throughout the Kansas River for assessing assemblage structure in summer 2007. Aerial imagery indicated riparian land use within 200 m from the river edge was dominated by agriculture in the upper river reaches (>35) and tended to increase in urban land use in the lower reaches (>58). Instream habitat complexity (number of braided channels, islands) also decreased with increased urban area (<25). Canonical correspondence analysis indicated that species that prefer high-velocity flows and sandy substrate (e.g., blue sucker Cycleptus elongatus and shovelnose sturgeon Scaphirhynchus platorynchus) were associated with the upper river reaches. Abundance of omnivorous and planktivorous fish species were also higher in the lower river. The presence of fluvial dependent and fluvial specialist species was associated with sites with higher water flows, more sand bars, and log jams. Our results suggest that conserving intolerant, native species in the Kansas River may require maintaining suitable habitat for these species and restoration of impacted areas of the river.
Sperm quality and cryopreservation of Brazilian freshwater fish species: a review.
Viveiros, A T M; Godinho, H P
2009-03-01
The Brazilian freshwater fish diversity is the richest in the world. Only 0.7% of all Brazilian species have had any aspect of their sperm biology addressed up to this date. The majority of the fish species described in this review migrate during the spawning season (a phenomenon known as piracema). Urbanization, pollution, hydroelectric dams and deforestation are some of the causes of stock depletion or even local extinction of some of these species. The knowledge concerning sperm quality and minimum sperm:egg ratio is important to maximize the use of males without reducing hatching rates. Furthermore, sperm cryopreservation and gene banking can guarantee the conservation of genetic diversity and development of adequate breeding programs of native fish species. In this review, we present and evaluate the existing information on Brazilian fish species that have been subject to sperm quality and cryopreservation studies. The following parameters were evaluated: volume of extractable sperm, sperm motility, sperm concentration, freezing media, freezing methods, and post-thaw sperm quality. Although the existing protocols yield relatively high post-thaw motility and fertilization rates, the use of cryopreserved sperm in routine hatchery production is still limited in Brazil.