Sample records for habitat requirements implications
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Demographic and habitat requirements for conservation of bull trout
Bruce E. Rieman; John D. Mclntyre
1993-01-01
Elements in bull trout biology, population dynamics, habitat, and biotic interactions important to conservation of the species are identified. Bull trout appear to have more specific habitat requirements than other salmonids, but no critical thresholds of acceptable habitat condition were found. Size, temporal variation, and spatial distribution are likely to influence...
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Determination of Habitat Requirements For Birds in Suburban Areas
Jack Ward Thomas; Richard M. DeGraaf; Joseph C. Mawson
1977-01-01
Songbird populations can be related to habitat components by a method that allows the simultaneous determination of habitat requirements for a variety of species . Through correlation and multiple-regression analyses, 10 bird species were studied in a suburban habitat, which was stratified according to human density. Variables used to account for bird distribution...
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Effect of reproductive rate on minimum habitat requirements of forest-breeding birds
Melissa D. Vance; Lenore Fahrig; Curtis H. Flather
2003-01-01
A major challenge facing conservation biologists and wildlife managers is to predict how fauna will respond to habitat loss. Different species require different amounts of habitat for population persistence, and speciesâ reproductive rates have been identified as one of the major factors affecting these habitat-amount requirements. The purpose of this study was to test...
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Armstrong, David S.; Parker, Gene W.
2003-01-01
species that would have been expected to occur in this area. Streamflow records from the gaging station Usquepaug River near Usquepaug were used to (1) determine streamflow requirements for habitat protection by use of the Tennant method, and (2) define a flow regime that mimics the river's natural flow regime by use of the Range of Variability Approach. The Tennant streamflow requirement, defined as 30 percent of the mean annual flow, was 0.64 cubic feet per second per square mile (ft3/s/mi2). This requirement should be considered an initial estimate because flows measured at the Usquepaug River gaging station are reduced by water withdrawals upstream from the gage. The streamflow requirements may need to be revised once a watershed-scale precipitationrunoff model of the Usquepaug River is complete and a simulation of streamflows without water withdrawals has been determined. Streamflow requirements for habitat protection were also determined at seven riffle sites by use of the Wetted-Perimeter and R2Cross methods. Two of these sites were on the mainstem Usquepaug River, one was on the mainstem Queen River, and four were on tributaries and the headwaters of the Queen River. Median streamflow requirements for habitat protection for these sites were 0.41 (ft3/s)/mi2, determined by the Wetted-Perimeter method and 0.72 ft3/s/mi2, determined by the R2Cross method.
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Determination of habitat requirements for Apache Trout
Petre, Sally J.; Bonar, Scott A.
2017-01-01
The Apache Trout Oncorhynchus apache, a salmonid endemic to east-central Arizona, is currently listed as threatened under the U.S. Endangered Species Act. Establishing and maintaining recovery streams for Apache Trout and other endemic species requires determination of their specific habitat requirements. We built upon previous studies of Apache Trout habitat by defining both stream-specific and generalized optimal and suitable ranges of habitat criteria in three streams located in the White Mountains of Arizona. Habitat criteria were measured at the time thought to be most limiting to juvenile and adult life stages, the summer base flow period. Based on the combined results from three streams, we found that Apache Trout use relatively deep (optimal range = 0.15–0.32 m; suitable range = 0.032–0.470 m) pools with slow stream velocities (suitable range = 0.00–0.22 m/s), gravel or smaller substrate (suitable range = 0.13–2.0 [Wentworth scale]), overhead cover (suitable range = 26–88%), and instream cover (large woody debris and undercut banks were occupied at higher rates than other instream cover types). Fish were captured at cool to moderate temperatures (suitable range = 10.4–21.1°C) in streams with relatively low maximum seasonal temperatures (optimal range = 20.1–22.9°C; suitable range = 17.1–25.9°C). Multiple logistic regression generally confirmed the importance of these variables for predicting the presence of Apache Trout. All measured variables except mean velocity were significant predictors in our model. Understanding habitat needs is necessary in managing for persistence, recolonization, and recruitment of Apache Trout. Management strategies such as fencing areas to restrict ungulate use and grazing and planting native riparian vegetation might favor Apache Trout persistence and recolonization by providing overhead cover and large woody debris to form pools and instream cover, shading streams and lowering temperatures.
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Restoring and rehabilitating sagebrush habitats
Pyke, David A.; Knick, S.T.; Connelly, J.W.
2011-01-01
Less than half of the original habitat of the Greater Sage-Grouse (Centrocercus uropha-sianus) currently exists. Some has been perma-nently lost to farms and urban areas, but the remaining varies in condition from high quality to no longer adequate. Restoration of sagebrush (Artemisia spp.) grassland ecosystems may be pos-sible for resilient lands. However, Greater Sage-Grouse require a wide variety of habitats over large areas to complete their life cycle. Effective restoration will require a regional approach for prioritizing and identifying appropriate options across the landscape. A landscape triage method is recommended for prioritizing lands for restora-tion. Spatial models can indicate where to protect and connect intact quality habitat with other simi-lar habitat via restoration. The ecological site con-cept of land classification is recommended for characterizing potential habitat across the region along with their accompanying state and transi-tion models of plant community dynamics. These models assist in identifying if passive, manage-ment-based or active, vegetation manipulation?based restoration might accomplish the goals of improved Greater Sage-Grouse habitat. A series of guidelines help formulate questions that manag-ers might consider when developing restoration plans: (1) site prioritization through a landscape triage; (2) soil verification and the implications of soil features on plant establishment success; (3) a comparison of the existing plant community to the potential for the site using ecological site descriptions; (4) a determination of the current successional status of the site using state and transition models to aid in predicting if passive or active restoration is necessary; and (5) implemen-tation of post-treatment monitoring to evaluate restoration effectiveness and post-treatment man-agement implications to restoration success.
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NASA Astrophysics Data System (ADS)
Wolaver, B. D.; Pierre, J. P.; Labay, B. J.; Ryberg, W. A.; Hibbits, T. J.; Prestridge, H. L.
2015-12-01
Anthropogenic land use changes have caused widespread wetland loss and fragmentation. This trend has important implications for aquatic biota conservation, including the semi-aquatic Western Chicken Turtle (Deirochelys reticularia miaria). This species inhabits seasonally inundated, ephemeral water bodies and adjacent uplands in the southeastern U.S. However, wetland conversion to agriculture and urbanization is thought to cause the species' decline, particularly in Texas, which includes the westernmost part of its range. Because the species moves only a few kilometers between wetlands, it particularly sensitive to habitat loss and fragmentation. Thus, as part of the only state-funded species research program, this study provides the U.S. Fish and Wildlife Service (FWS) with scientific data to determine if the species warrants protection under the Endangered Species Act (ESA). We use a species distribution model to map potentially suitable habitat for most of East Texas. We evaluate landscape-scale anthropogenic activities in this region which may be contributing to the species' decline. We identify areas of urbanization, agricultural expansion, forestry, and resulting wetland loss. We find that between 2001 and 2011 approximately 80 km2 of wetlands were lost in potentially suitable habitat, including the urbanizing Houston area. We use spatial geostatistics to quantify wetland habitat fragmentation. We also introduce the Habitat Alteration Index (HAI), which calculates total landscape alteration and mean probability of occurrence to identify high-quality habitat most at risk of recent anthropogenic alteration. Population surveys by biologists are targeting these areas and future management actions may focus on mitigating anthropogenic activities there. While this study focuses on D. r. miaria, this approach can evaluate wetland habitat of other aquatic organisms.
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Estavillo, Candelaria; Pardini, Renata; da Rocha, Pedro Luís Bernardo
2013-01-01
Habitat loss is the main driver of the current biodiversity crisis, a landscape-scale process that affects the survival of spatially-structured populations. Although it is well-established that species responses to habitat loss can be abrupt, the existence of a biodiversity threshold is still the cause of much controversy in the literature and would require that most species respond similarly to the loss of native vegetation. Here we test the existence of a biodiversity threshold, i.e. an abrupt decline in species richness, with habitat loss. We draw on a spatially-replicated dataset on Atlantic forest small mammals, consisting of 16 sampling sites divided between forests and matrix habitats in each of five 3600-ha landscapes (varying from 5% to 45% forest cover), and on an a priori classification of species into habitat requirement categories (forest specialists, habitat generalists and open-area specialists). Forest specialists declined abruptly below 30% of forest cover, and spillover to the matrix occurred only in more forested landscapes. Generalists responded positively to landscape heterogeneity, peaking at intermediary levels of forest cover. Open area specialists dominated the matrix and did not spillover to forests. As a result of these distinct responses, we observed a biodiversity threshold for the small mammal community below 30% forest cover, and a peak in species richness just above this threshold. Our results highlight that cross habitat spillover may be asymmetrical and contingent on landscape context, occurring mainly from forests to the matrix and only in more forested landscapes. Moreover, they indicate the potential for biodiversity thresholds in human-modified landscapes, and the importance of landscape heterogeneity to biodiversity. Since forest loss affected not only the conservation value of forest patches, but also the potential for biodiversity-mediated services in anthropogenic habitats, our work indicates the importance of proactive
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Effective environmental policy decisions benefit from stream habitat information that is accurate, precise, and relevant. The recent National Wadeable Streams Assessment (NWSA) carried out by the U.S. EPA required physical habitat information sufficiently comprehensive to facilit...
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NASA Astrophysics Data System (ADS)
Linderman, Marc Alan
We examined an approach to classifying understory bamboo, the staple food of the giant panda (Ailuropoda melanoleuca), from remote sensing imagery in the Wolong Nature Reserve, China. We also used these data to estimate the landscape-scale distribution of giant panda habitat, and model the human effects on forest cover and the spatio-temporal dynamics of bamboo and the resulting implications for giant panda habitat. The spatial distribution of understory bamboo was mapped using an artificial neural network and leaf-on remote sensing data. Training on a limited set of ground truth data and using widely available Landsat TM data as input, a non-linear artificial neural network achieved a classification accuracy of 80% despite the presence of co-occurring mid-story and understory vegetation. Using information on the spatial distribution of bamboo in Wolong, we compared the results of giant panda habitat analyses with and without bamboo information. Total amount of habitat decreased by 29--56% and overall habitat patch size decreased by 16--48% after bamboo information was incorporated into the analyses. The decreases in the quantity of panda habitat and increases in habitat fragmentation resulted in decreases of 41--60% in carrying capacity. Using a spatio-temporal model of bamboo dynamics and human activities, we found that local fuelwood collection and household creation will likely reduce secondary habitat relied upon by pandas. Human impacts would likely contribute up to an additional 16% loss of habitat. Furthermore, these impacts primarily occur in the habitat relied upon by giant pandas during past bamboo die-offs. Decreased total area of habitat and increased fragmentation from human activities will likely make giant pandas increasingly sensitive to natural disturbances such as cyclical bamboo die-offs. Our studies suggest that it is necessary to further examine approaches to monitor understory vegetation and incorporate understory information into wildlife
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Armstrong, David S.; Richards, Todd A.; Parker, Gene W.
2001-01-01
The relations among stream habitat, fish communities, and hydrologic conditions were investigated in the Ipswich River Basin in northeastern Massachusetts. Data were assessed from 27 sites on the mainstem of the Ipswich River from July to September 1998 and from 10 sites on 5 major tributaries in July and August 1999. Habitat assessments made in 1998 determined that in a year with sustained streamflow for most of the summer, the Ipswich River contains diverse, high-quality aquatic habitat. Channel types are predominantly low gradient glides, pools, and impoundments, with a sandy streambed and a forest or shrub riparian zone. Features that provide fish habitat are located mostly along stream margins; these features include overhanging brush, undercut banks, exposed roots, and woody debris. These habitat features decrease in availability to aquatic communities with declining streamflows and generally become unavailable after streamflows drop to the point where the edge of water recedes from the stream banks.The mainstem and tributaries were sampled to determine fish species composition, relative abundance, and length frequency. Fish sampling indicates that the fish community in the Ipswich River is currently a warm-water fish community dominated by pond-type fish. However, historical temperature data, and survival of stocked trout in the mainstem Ipswich into late summer of 1998, indicate that the Ipswich River potentially could support cold-water fish species if adequate flows are maintained. Dominant fish species sampled in the mainstem Ipswich River were redfin pickerel (Esox americanus), American eel (Anguilla rostrata), and pumpkinseed (Lepomis gibbosus), which together represented 41, 22, and 10 percent, respectively, of 4,745 fish sampled. The fish communities of the mainstem and tributaries contained few fluvial-dependent or fluvial-specialist species (requiring flow), and were dominated by macrohabitat generalists (tolerant of low-flow, warm-water, and
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NASA Astrophysics Data System (ADS)
Bergen, K. M.; Goetz, S. J.; Dubayah, R. O.; Henebry, G. M.; Hunsaker, C. T.; Imhoff, M. L.; Nelson, R. F.; Parker, G. G.; Radeloff, V. C.
2009-06-01
Biodiversity and habitat face increasing pressures due to human and natural influences that alter vegetation structure. Because of the inherent difficulty of measuring forested vegetation three-dimensional (3-D) structure on the ground, this important component of biodiversity and habitat has been, until recently, largely restricted to local measurements, or at larger scales to generalizations. New lidar and radar remote sensing instruments such as those proposed for spaceborne missions will provide the capability to fill this gap. This paper reviews the state of the art for incorporatinginformation on vegetation 3-D structure into biodiversity and habitat science and management approaches, with emphasis on use of lidar and radar data. First we review relationships between vegetation 3-D structure, biodiversity and habitat, and metrics commonly used to describe those relationships. Next, we review the technical capabilities of new lidar and radar sensors and their application to biodiversity and habitat studies to date. We then define variables that have been identified as both useful and feasible to retrieve from spaceborne lidar and radar observations and provide their accuracy and precision requirements. We conclude with a brief discussion of implications for spaceborne missions and research programs. The possibility to derive vegetation 3-D measurements from spaceborne active sensors and to integrate them into science and management comes at a critical juncture for global biodiversity conservation and opens new possibilities for advanced scientific analysis of habitat and biodiversity.
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Chadwick P. Lehman; Mark A. Rumble; Michael A. Battaglia; Todd R. Mills; Lance A. Asherin
2016-01-01
Understanding response of ponderosa pine (Pinus ponderosa) forest development following a mountain pine beetle (MPB; Dendroctonus ponderosae) epidemic has important management implications for winter habitat conditions for Merriamâs wild turkeys (Meleagris gallopavo merriami; hereafter, turkeys). Therefore, we quantified habitat changes over time for turkeys...
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Felton, Adam; Sonesson, Johan; Nilsson, Urban; Lämås, Tomas; Lundmark, Tomas; Nordin, Annika; Ranius, Thomas; Roberge, Jean-Michel
2017-04-01
Because of the limited spatial extent and comprehensiveness of protected areas, an increasing emphasis is being placed on conserving habitats which promote biodiversity within production forest. For this reason, alternative silvicultural programs need to be evaluated with respect to their implications for forest biodiversity, especially if these programs are likely to be adopted. Here we simulated the effect of varied rotation length and associated thinning regimes on habitat availability in Scots pine and Norway spruce production forests, with high and low productivity. Shorter rotation lengths reduced the contribution made by production trees (trees grown for industrial use) to the availability of key habitat features, while concurrently increasing the contribution from retention trees. The contribution of production trees to habitat features was larger for high productivity sites, than for low productivity sites. We conclude that shortened rotation lengths result in losses of the availability of habitat features that are key for biodiversity conservation and that increased retention practices may only partially compensate for this. Ensuring that conservation efforts better reflect the inherent variation in stand rotation lengths would help improve the maintenance of key forest habitats in production forests.
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Habitat area requirements of breeding forest birds of the middle Atlantic states
Robbins, Chandler S.; Dawson, Deanna K.; Dowell, Barbara A.
1989-01-01
Conservation of birds requires an understanding of their nesting requirements, including area as well as structural characteristics of the habitat. Previous studies have shown that many neotropical migrant bird species seem to depend on extensive forested areas, but the specific area requirements of individual species have not been clarified sufficiently to aid in design and management of effective preserves. For this 5-year study, bird and vegetation data were obtained at 469 points in forests ranging in area from 0.1 ha to more than 3,000 ha in Maryland and adjacent states. Data were analyzed first by stepwise regression to identify habitat factors that had the greatest influence on relative abundance of each bird species. In the relatively undisturbed mature forests studied, degree of isolation and area were significant predictors of relative abundance for more bird species than were any habitat variables. For species for which forest area was a significant predictor of abundance, we used logistic regression to examine the relationship between forest area and the probability of detecting the species. In managing forest lands for wildlife, top priority should go toward providing for the needs of area-sensitive or rare species rather than increasing species diversity per se. Avian species that occur in small and disturbed forests are generalists that are adapted to survival under edge conditions and need no special assistance from man. Forest reserves with thousands of hectares are required to have the highest probability of providing for the least common species of forest birds in a region. However, if preservation of large contiguous forest tracts is not a realistic option, results of this study suggest 2 alternative approaches. First, if other habitat attributes also are considered, smaller forests may provide suitable breeding sites for relatively rare species. Second, smaller tracts in close proximity to other forests may serve to attract or retain area
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Landscape selection by piping plovers has implications for measuring habitat and population size
Anteau, Michael J.; Shaffer, Terry L.; Wiltermuth, Mark T.; Sherfy, Mark H.
2014-01-01
How breeding birds distribute in relation to landscape-scale habitat features has important implications for conservation because those features may constrain habitat suitability. Furthermore, knowledge of these associations can help build models to improve area-wide demographic estimates or to develop a sampling stratification for research and monitoring. This is particularly important for rare species that have uneven distributions across vast areas, such as the federally listed piping plover (Charadrius melodus; hereafter plover). We examined how remotely-sensed landscape features influenced the distribution of breeding plover pairs among 2-km shoreline segments during 2006–2009 at Lake Sakakawea in North Dakota, USA. We found strong associations between remotely-sensed landscape features and plover abundance and distribution (R2 = 0.65). Plovers were nearly absent from segments with bluffs (>25 m elevation increase within 250 m of shoreline). Relative plover density (pairs/ha) was markedly greater on islands (4.84 ± 1.22 SE) than on mainlands (0.85 ± 0.17 SE). Pair numbers increased with abundance of nesting habitat (unvegetated-flat areas β^=0.28±0.08SE ). On islands, pair numbers also increased with the relative proportion of the total area that was habitat ( β^=3.27±0.46SE ). Our model could be adapted to estimate the breeding population of plovers or to make predictions that provide a basis for stratification and design of future surveys. Knowledge of landscape features, such as bluffs, that exclude use by birds refines habitat suitability and facilitates more accurate estimates of habitat and population abundance, by decreasing the size of the sampling universe. Furthermore, techniques demonstrated here are applicable to other vast areas where birds breed in sparse or uneven densities.
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Markle, Chantel E; Chow-Fraser, Gillian; Chow-Fraser, Patricia
2018-01-01
Point Pelee National Park, located at the southern-most tip of Canada's mainland, historically supported a large number of herpetofauna species; however, despite nearly a century of protection, six snake and five amphibian species have disappeared, and remaining species-at-risk populations are thought to be in decline. We hypothesized that long-term changes in availability and distribution of critical habitat types may have contributed to the disappearance of herpetofauna. To track habitat changes we used aerial image data spanning 85 years (1931-2015) and manually digitized and classified image data using a standardized framework. Change-detection analyses were used to evaluate the relative importance of proportionate loss and fragmentation of 17 habitat types. Marsh habitat diversity and aquatic connectivity has declined since 1931. The marsh matrix transitioned from a graminoid and forb shallow marsh interspersed with water to a cattail dominated marsh, altering critical breeding, foraging, and overwintering habitat. Reduced diversity of marsh habitats appears to be linked to the expansion of invasive Phragmites australis, which invaded prior to 2000. Loss of open habitats such as savanna and meadow has reduced availability of high quality thermoregulation habitat for reptiles. Restoration of the northwestern region and tip of Point Pelee National Park to a mixed landscape of shallow wetlands (cattail, graminoid, forb, open water) and eradication of dense Phragmites stands should improve habitat diversity. Our results suggest that long-term landscape changes resulting from habitat succession and invasive species can negatively affect habitat suitability for herpetofauna and protection of land alone does not necessarily equate to protection of sensitive herpetofauna.
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Quantifying home range habitat requirements for bobcats (Lynx rufus) in Vermont, USA
Donovan, T.M.; Freeman, M.; Abouelezz, H.; Royar, Kim; Howard, A.; Mickey, R.
2011-01-01
ranges consisted of both beneficial and detrimental habitat types. We discuss the application of habitat suitability mapping and home range requirements for bobcat conservation and landscape scale management. ?? 2011.
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Chow-Fraser, Gillian; Chow-Fraser, Patricia
2018-01-01
Point Pelee National Park, located at the southern-most tip of Canada’s mainland, historically supported a large number of herpetofauna species; however, despite nearly a century of protection, six snake and five amphibian species have disappeared, and remaining species-at-risk populations are thought to be in decline. We hypothesized that long-term changes in availability and distribution of critical habitat types may have contributed to the disappearance of herpetofauna. To track habitat changes we used aerial image data spanning 85 years (1931–2015) and manually digitized and classified image data using a standardized framework. Change-detection analyses were used to evaluate the relative importance of proportionate loss and fragmentation of 17 habitat types. Marsh habitat diversity and aquatic connectivity has declined since 1931. The marsh matrix transitioned from a graminoid and forb shallow marsh interspersed with water to a cattail dominated marsh, altering critical breeding, foraging, and overwintering habitat. Reduced diversity of marsh habitats appears to be linked to the expansion of invasive Phragmites australis, which invaded prior to 2000. Loss of open habitats such as savanna and meadow has reduced availability of high quality thermoregulation habitat for reptiles. Restoration of the northwestern region and tip of Point Pelee National Park to a mixed landscape of shallow wetlands (cattail, graminoid, forb, open water) and eradication of dense Phragmites stands should improve habitat diversity. Our results suggest that long-term landscape changes resulting from habitat succession and invasive species can negatively affect habitat suitability for herpetofauna and protection of land alone does not necessarily equate to protection of sensitive herpetofauna. PMID:29444129
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D.W. Reiser; T.C. Bjornn
1979-01-01
Habitat requirements of anadromous and some resident salmonid fishes have been described for various life stages, including upstream migration of adults, spawning, incubation, and juvenile rearing. Factors important in the migration of adults are water temperature, minimum water depth, maximum water velocity, turbidity, dissolved oxygen, and...
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Diehl, Robert H.
2013-01-01
A preconception concerning habitat persists and has gone unrecognized since use of the term first entered the lexicon of ecological and evolutionary biology many decades ago. Specifically, land and water are considered habitats, while the airspace is not. This might at first seem a reasonable, if unintended, demarcation, since years of education and personal experience as well as limits to perception predispose a traditional view of habitat. Nevertheless, the airspace satisfies the definition and functional role of a habitat, and its recognition as habitat may have implications for policy where expanding anthropogenic development of airspace could impact the conservation of species and subject parts of the airspace to formalized legal protection.
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Quantifying home range habitat requirements for bobcats (Lynx rufus) in Vermont, USA
Donovan, Therese; Freeman, Mark; Abouelezz, Hanem; Royar, Kim; Howard, Alan D.; Mickey, R.
2011-01-01
that home ranges consisted of both beneficial and detrimental habitat types. We discuss the application of habitat suitability mapping and home range requirements for bobcat conservation and landscape scale management.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Shen, H.W.; Hiew, K.L.; Loubser, E.
1985-11-01
The Whooping Crane, an endangered species, uses the Platte River downstream from Overton, Nebraska in its migratory route. Maintenance of favorable habitat conditions required by law may mean restrictions on development and management of Colorado's entitled water in the South Platte River. The project investigated meeting crane habitat flow requirements by alternative plans for flow releases through Kingsley Dam (North Platte River) and Narrows Dam (a proposed project on the South Platte River). The analysis is based on mean monthly flow of the past 39 years. Irrigation releases were held firm, hydroelectric power production was maximized, and flows available tomore » meet habitat requirements were determined. A simulation model was developed to model the operation of the North Platte and South Platte Rivers.« less
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Habitat connectivity and ecosystem productivity: implications from a simple model.
Cloern, J.E.
2007-01-01
The import of resources (food, nutrients) sustains biological production and food webs in resource-limited habitats. Resource export from donor habitats subsidizes production in recipient habitats, but the ecosystem-scale consequences of resource translocation are generally unknown. Here, I use a nutrient-phytoplankton-zooplankton model to show how dispersive connectivity between a shallow autotrophic habitat and a deep heterotrophic pelagic habitat can amplify overall system production in metazoan food webs. This result derives from the finite capacity of suspension feeders to capture and assimilate food particles: excess primary production in closed autotrophic habitats cannot be assimilated by consumers; however, if excess phytoplankton production is exported to food-limited heterotrophic habitats, it can be assimilated by zooplankton to support additional secondary production. Transport of regenerated nutrients from heterotrophic to autotrophic habitats sustains higher system primary production. These simulation results imply that the ecosystem-scale efficiency of nutrient transformation into metazoan biomass can be constrained by the rate of resource exchange across habitats and that it is optimized when the transport rate matches the growth rate of primary producers. Slower transport (i.e., reduced connectivity) leads to nutrient limitation of primary production in autotrophic habitats and food limitation of secondary production in heterotrophic habitats. Habitat fragmentation can therefore impose energetic constraints on the carrying capacity of aquatic ecosystems. The outcomes of ecosystem restoration through habitat creation will be determined by both functions provided by newly created aquatic habitats and the rates of hydraulic connectivity between them.
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California red-legged frog (Rana draytonii) movement and habitat use: Implications for conservation
Fellers, G.M.; Kleeman, P.M.
2007-01-01
Nonbreeding habitats are critically important for Rana draytonii, especially for individuals that breed in temporary bodies of water. We radiotracked 123 frogs to evaluate seasonal habitat use. Individual frogs were continuously tracked for up to 16 months. Some individuals remained at breeding ponds all year, but 66% of female and 25% of male frogs moved to nonbreeding areas, even when the breeding site retained water. Frogs at our main study site moved 150 m (median), roughly the distance to the nearest suitable nonbreeding area. The greatest straight-line distance traveled was 1.4 km, although the presumed distance traveled was 2.8 km. Females were more likely than males to move from permanent ponds (38% of females, 16% of males), but among dispersing frogs, males and females did not differ in distance moved. Some frogs left breeding sites shortly after oviposition (median = 12 days for females, 42.5 days for males), but many individuals remained until the site was nearly dry. Fog provided moisture for dispersal or migration throughout the summer. Our data demonstrate that maintaining populations of pond-breeding amphibians requires that all essential habitat components be protected; these include (1) breeding habitat, (2) nonbreeding habitat, and (3) migration corridors. In addition, a buffer is needed around all three areas to ensure that outside activities do not degrade any of the three habitat components. Copyright 2007 Society for the Study of Amphibians and Reptiles.
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Webber, Alyson F; Heath, Julie A; Fischer, Richard A
2013-01-01
Habitat use has important consequences for avian reproductive success and survival. In coastal areas with recreational activity, human disturbance may limit use of otherwise suitable habitat. Snowy plovers Charadrius nivosus have a patchy breeding distribution along the coastal areas on the Florida Panhandle, USA. Our goal was to determine the relative effects of seasonal human disturbance and habitat requirements on snowy plover habitat use. We surveyed 303 sites for snowy plovers, human disturbance, and habitat features between January and July 2009 and 2010. We made multiple visits during three different sampling periods that corresponded to snowy plover breeding: pre-breeding, incubation, and brood-rearing and used multi-season occupancy models to examine whether human disturbance, habitat features, or both influenced site occupancy, colonization (probability of transition from an unoccupied site to an occupied site), and extinction (probability of transition from an occupied site to an unoccupied site). Snowy plover site occupancy and colonization was negatively associated with human disturbance and site extinction was positively associated with human disturbance. Interdune vegetation had a negative effect on occupancy and colonization, indicating that plovers were less likely to use areas with uniform, dense vegetation among dunes. Also, dune shape, beach debris, and access to low-energy foraging areas influenced site occupancy, colonization, and extinction. Plovers used habitat based on beach characteristics that provided stage-specific resource needs; however, human disturbance was the strongest predictor of site occupancy. In addition, vegetation plantings used to enhance dune rehabilitation may negatively impact plover site occupancy. Management actions that decrease human disturbance, such as symbolic fencing and signage, may increase the amount of breeding habitat available to snowy plovers on the Florida Panhandle and in other areas with high human
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Bisson, P.A.; Dunham, J.B.; Reeves, G.H.
2009-01-01
In spite of numerous habitat restoration programs in fresh waters with an aggregate annual funding of millions of dollars, many populations of Pacific salmon remain significantly imperiled. Habitat restoration strategies that address limited environmental attributes and partial salmon life-history requirements or approaches that attempt to force aquatic habitat to conform to idealized but ecologically unsustainable conditions may partly explain this lack of response. Natural watershed processes generate highly variable environmental conditions and population responses, i.e., multiple life histories, that are often not considered in restoration. Examples from several locations underscore the importance of natural variability to the resilience of Pacific salmon. The implication is that habitat restoration efforts will be more likely to foster salmon resilience if they consider processes that generate and maintain natural variability in fresh water. We identify three specific criteria for management based on natural variability: the capacity of aquatic habitat to recover from disturbance, a range of habitats distributed across stream networks through time sufficient to fulfill the requirements of diverse salmon life histories, and ecological connectivity. In light of these considerations, we discuss current threats to habitat resilience and describe how regulatory and restoration approaches can be modified to better incorporate natural variability. ?? 2009 by the author(s).
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Hagen, Christian A.; Grisham, Blake A.; Boal, Clint W.; Haukos, David A.
2013-01-01
The distribution and range of lesser prairie-chicken (Tympanuchus pallidicinctus) has been reduced by >90% since European settlement of the Great Plains of North America. Currently, lesser prairie-chickens occupy 3 general vegetation communities: sand sagebrush (Artemisia filifolia), sand shinnery oak (Quercus havardii), and mixed-grass prairies juxtaposed with Conservation Reserve Program grasslands. As a candidate for protection under the Endangered Species Act, there is a need for a synthesis that characterizes habitat structure rangewide. Thus, we conducted a meta-analysis of vegetation characteristics at nest sites and brood habitats to determine whether there was an overall effect (Hedges' d) of habitat selection and to estimate average (95% CI) habitat characteristics at use sites. We estimated effect sizes (di) from the difference between use (nests and brood sites) and random sampling sites for each study (n = 14), and derived an overall effect size (d++). There was a general effect for habitat selection as evidenced by low levels of variation in effect sizes across studies and regions. There was a small to medium effect (d++) = 0.20-0.82) of selection for greater vertical structure (visual obstruction) by nesting females in both vegetation communities, and selection against bare ground (d++ = 0.20-0.58). Females with broods exhibited less selectivity for habitat components except for vertical structure. The variation of d++ was greater during nesting than brooding periods, signifying a seasonal shift in habitat use, and perhaps a greater range of tolerance for brood-rearing habitat. The overall estimates of vegetation cover were consistent with those provided in management guidelines for the species.
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Michael J. Wisdom; Richard S. Holthausen; Barbara C. Wales; Christina D. Hargis; Victoria A. Saab; Danny C. Lee; Wendel J. Hann; Terrell D. Rich; Mary M. Rowland; Wally J. Murphy; Michelle R. Eames
2000-01-01
We defined habitat requirements (source habitats) and assessed trends in these habitats for 91 species of terrestrial vertebrates on 58 million ha (145 million acres) of public and private lands within the interior Columbia basin (hereafter referred to as the basin). We also summarized knowledge about species-road relations for each species and mapped source habitats...
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NASA Astrophysics Data System (ADS)
Sherwood, Edward T.; Greening, Holly S.
2014-02-01
The Tampa Bay estuary is a unique and valued ecosystem that currently thrives between subtropical and temperate climates along Florida's west-central coast. The watershed is considered urbanized (42 % lands developed); however, a suite of critical coastal habitats still persists. Current management efforts are focused toward restoring the historic balance of these habitat types to a benchmark 1950s period. We have modeled the anticipated changes to a suite of habitats within the Tampa Bay estuary using the sea level affecting marshes model under various sea level rise (SLR) scenarios. Modeled changes to the distribution and coverage of mangrove habitats within the estuary are expected to dominate the overall proportions of future critical coastal habitats. Modeled losses in salt marsh, salt barren, and coastal freshwater wetlands by 2100 will significantly affect the progress achieved in "Restoring the Balance" of these habitat types over recent periods. Future land management and acquisition priorities within the Tampa Bay estuary should consider the impending effects of both continued urbanization within the watershed and climate change. This requires the recognition that: (1) the Tampa Bay estuary is trending towards a mangrove-dominated system; (2) the current management paradigm of "Restoring the Balance" may no longer provide realistic, attainable goals; (3) restoration that creates habitat mosaics will prove more resilient in the future; and (4) establishing subtidal and upslope "refugia" may be a future strategy in this urbanized estuary to allow sensitive habitat types (e.g., seagrass and salt barren) to persist under anticipated climate change and SLR impacts.
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Sherwood, Edward T; Greening, Holly S
2014-02-01
The Tampa Bay estuary is a unique and valued ecosystem that currently thrives between subtropical and temperate climates along Florida's west-central coast. The watershed is considered urbanized (42 % lands developed); however, a suite of critical coastal habitats still persists. Current management efforts are focused toward restoring the historic balance of these habitat types to a benchmark 1950s period. We have modeled the anticipated changes to a suite of habitats within the Tampa Bay estuary using the sea level affecting marshes model under various sea level rise (SLR) scenarios. Modeled changes to the distribution and coverage of mangrove habitats within the estuary are expected to dominate the overall proportions of future critical coastal habitats. Modeled losses in salt marsh, salt barren, and coastal freshwater wetlands by 2100 will significantly affect the progress achieved in "Restoring the Balance" of these habitat types over recent periods. Future land management and acquisition priorities within the Tampa Bay estuary should consider the impending effects of both continued urbanization within the watershed and climate change. This requires the recognition that: (1) the Tampa Bay estuary is trending towards a mangrove-dominated system; (2) the current management paradigm of "Restoring the Balance" may no longer provide realistic, attainable goals; (3) restoration that creates habitat mosaics will prove more resilient in the future; and (4) establishing subtidal and upslope "refugia" may be a future strategy in this urbanized estuary to allow sensitive habitat types (e.g., seagrass and salt barren) to persist under anticipated climate change and SLR impacts.
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Habitat loss and gain: Influence on habitat attractiveness for estuarine fish communities
NASA Astrophysics Data System (ADS)
Amorim, Eva; Ramos, Sandra; Elliott, Michael; Franco, Anita; Bordalo, Adriano A.
2017-10-01
Habitat structure and complexity influence the structuring and functioning of fish communities. Habitat changes are one of the main pressures affecting estuarine systems worldwide, yet the degree and rate of change and its impact on fish communities is still poorly understood. In order to quantify historical modifications in habitat structure, an ecohydrological classification system using physiotopes, i.e. units with homogenous abiotic characteristics, was developed for the lower Lima estuary (NW Portugal). Field data, aerial imagery, historical maps and interpolation methods were used to map input variables, including bathymetry, substratum (hard/soft), sediment composition, hydrodynamics (current velocity) and vegetation coverage. Physiotopes were then mapped for the years of 1933 and 2013 and the areas lost and gained over the 80 years were quantified. The implications of changes for the benthic and demersal fish communities using the lower estuary were estimated using the attractiveness to those communities of each physiotope, while considering the main estuarine habitat functions for fish, namely spawning, nursery, feeding and refuge areas and migratory routes. The lower estuary was highly affected due to urbanisation and development and, following a port/harbour expansion, its boundary moved seaward causing an increase in total area. Modifications led to the loss of most of its sandy and saltmarsh intertidal physiotopes, which were replaced by deeper subtidal physiotopes. The most attractive physiotopes for fish (defined as the way in which they supported the fish ecological features) decreased in area while less attractive ones increased, producing an overall lower attractiveness of the studied area in 2013 compared to 1933. The implications of habitat alterations for the fish using the estuary include potential changes in the nursery carrying capacity and the functioning of the fish community. The study also highlighted the poor knowledge of the impacts of
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Chapter 5. Using Habitat Models for Habitat Mapping and Monitoring
Samuel A. Cushman; Timothy J. Mersmann; Gretchen G. Moisen; Kevin S. McKelvey; Christina D. Vojta
2013-01-01
This chapter provides guidance for applying existing habitat models to map and monitor wildlife habitat. Chapter 2 addresses the use of conceptual models to create a solid foundation for selecting habitat attributes to monitor and to translate these attributes into quantifiable and reportable monitoring measures. Most wildlife species, however, require a complex suite...
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Habitat requirements and burrowing depths of rodents in relation to shallow waste burial sites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gano, K.A.; States, J.B.
1982-05-01
The purpose of this paper is to provide a review of the literature and summarize information on factors affecting habitat selection and maximum recorded burrowing depths for representative small mammals that we consider most likely to inhibit waste burial sites in arid and semi-arid regions of the West. The information is intended for waste management designers who need to know what to expect from small mammals that may be present at a particular site. Waste repositories oculd be designed to exclude the deep burrowing rodents of a region by creating an unattractive habitat over the waste. Summaries are given formore » habitat requirements of each group along with generalized modifications that could be employed to deter habitation. Representatives from the major groups considered to be deep burrowers are discussed. Further, detailed information about a particular species can be obtained from the references cited.« less
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Ecomorphology and phylogenetic risk: Implications for habitat reconstruction using fossil bovids.
Scott, Robert S; Barr, W Andrew
2014-08-01
Reconstructions of paleohabitats are necessary aids in understanding hominin evolution. The morphology of species from relevant sites, understood in terms of functional relationships to habitat (termed ecomorphology), offers a direct link to habitat. Bovids are a speciose radiation that includes many habitat specialists and are abundant in the fossil record. Thus, bovids are extremely common in ecomorphological analyses. However, bovid phylogeny and habitat preference are related, which raises the possibility that analyses linking habitat with morphology are not 'taxon free' but 'taxon-dependent.' Here we analyze eight relative dimensions and one shape index of the metatarsal for a sample of 72 bovid species and one antilocaprid. The selected variables have been previously shown to have strong associations with habitat and to have functional explanations for these associations. Phylogenetic generalized least squares analyses of these variables, including habitat and size, resulted in estimates for the parameter lambda (used to model phylogenetic signal) varying from zero to one. Thus, while phylogeny, morphology, and habitat all march together among the bovids, the odds that phylogeny confounds ecomorphological analyses may vary depending on particular morphological characteristics. While large values of lambda do not necessarily indicate that habitat differences are unimportant drivers of morphology, we consider the low value of lambda for relative metatarsal width suggestive that conclusions about habitat built on observations of this particular morphology carry with them less 'phylogenetic risk.' We suggest that the way forward for ecomorphology is grounded in functionally relevant observations and careful consideration of phylogeny designed to bracket probable habitat preferences appropriately. Separate consideration of different morphological variables may help to determine the level of 'phylogenetic risk' attached to conclusions linking habitat and morphology
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NASA Technical Reports Server (NTRS)
Zipay, John Joseph
2016-01-01
A technique for rapidly determining the relationship between the pressurized volume, structural mass and the cryogenic propellant required to be delivered to Earth orbit for a Mars Transit Habitat is provided. This technique is based on assumptions for the required delta-V's, the Exploration Upper Stage performance and the historical structural masses for human spacecraft from Mercury Program through the International Space Station. If the Mars Transit Habitat is constructed from aluminum, structural mass estimates based on the habitat pressurized volume are accurate to within 15%. Other structural material options for the Mars Transit Habitat are also evaluated. The results show that small, achievable reductions in the structural mass of the Transit Habitat can save tens of thousands of pounds of cryogenic propellant that need to be delivered to Earth orbit for a human Phobos Mission.
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NASA Technical Reports Server (NTRS)
Zipay, John J.
2016-01-01
A technique for rapidly determining the relationship between the pressurized volume, structural mass and the cryogenic propellant required to be delivered to Earth orbit for a Mars Transit Habitat is provided. This technique is based on assumptions for the required delta-V's, the Exploration Upper Stage performance and the historical structural masses for human spacecraft from Mercury Program through the International Space Station. If the Mars Transit Habitat is constructed from aluminum, structural mass estimates based on the habitat pressurized volume are accurate to within 15 percent. Other structural material options for the Mars Transit Habitat are also evaluated. The results show that small, achievable reductions in the structural mass of the Transit Habitat can save tens of thousands of pounds of cryogenic propellant that need to be delivered to Earth orbit for a human Phobos Mission.
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Newly Discovered Orangutan Species Requires Urgent Habitat Protection.
Sloan, Sean; Supriatna, Jatna; Campbell, Mason J; Alamgir, Mohammed; Laurance, William F
2018-05-03
Nater, et al.[1] recently identified a new orangutan species (Pongo tapanuliensis) in northern Sumatra, Indonesia-just the seventh described species of living great ape. The population of this critically-endangered species is perilously small, at only ∼800 individuals [1], ranking it among the planet's rarest fauna. We assert that P. tapanuliensis is highly vulnerable to extinction because its remaining habitat is small, fragmented, and poorly protected. While road incursions within its habitat are modest-road density is only one-eighth that of northern Sumatra-over one-fifth of its habitat is zoned for agricultural conversion or is comprised of mosaic agricultural and regrowth/degraded forest. Additionally, a further 8% will be affected by flooding and infrastructure development for a hydroelectric project. We recommend urgent steps to increase the chance that P. tapanuliensis will persist in the wild. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Amaral, Katrina E; Palace, Michael; O'Brien, Kathleen M; Fenderson, Lindsey E; Kovach, Adrienne I
2016-01-01
Landscape modification and habitat fragmentation disrupt the connectivity of natural landscapes, with major consequences for biodiversity. Species that require patchily distributed habitats, such as those that specialize on early successional ecosystems, must disperse through a landscape matrix with unsuitable habitat types. We evaluated landscape effects on dispersal of an early successional obligate, the New England cottontail (Sylvilagus transitionalis). Using a landscape genetics approach, we identified barriers and facilitators of gene flow and connectivity corridors for a population of cottontails in the northeastern United States. We modeled dispersal in relation to landscape structure and composition and tested hypotheses about the influence of habitat fragmentation on gene flow. Anthropogenic and natural shrubland habitats facilitated gene flow, while the remainder of the matrix, particularly development and forest, impeded gene flow. The relative influence of matrix habitats differed between study areas in relation to a fragmentation gradient. Barrier features had higher explanatory power in the more fragmented site, while facilitating features were important in the less fragmented site. Landscape models that included a simultaneous barrier and facilitating effect of roads had higher explanatory power than models that considered either effect separately, supporting the hypothesis that roads act as both barriers and facilitators at all spatial scales. The inclusion of LiDAR-identified shrubland habitat improved the fit of our facilitator models. Corridor analyses using circuit and least cost path approaches revealed the importance of anthropogenic, linear features for restoring connectivity between the study areas. In fragmented landscapes, human-modified habitats may enhance functional connectivity by providing suitable dispersal conduits for early successional specialists.
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Amaral, Katrina E.; Palace, Michael; O’Brien, Kathleen M.; Fenderson, Lindsey E.; Kovach, Adrienne I.
2016-01-01
Landscape modification and habitat fragmentation disrupt the connectivity of natural landscapes, with major consequences for biodiversity. Species that require patchily distributed habitats, such as those that specialize on early successional ecosystems, must disperse through a landscape matrix with unsuitable habitat types. We evaluated landscape effects on dispersal of an early successional obligate, the New England cottontail (Sylvilagus transitionalis). Using a landscape genetics approach, we identified barriers and facilitators of gene flow and connectivity corridors for a population of cottontails in the northeastern United States. We modeled dispersal in relation to landscape structure and composition and tested hypotheses about the influence of habitat fragmentation on gene flow. Anthropogenic and natural shrubland habitats facilitated gene flow, while the remainder of the matrix, particularly development and forest, impeded gene flow. The relative influence of matrix habitats differed between study areas in relation to a fragmentation gradient. Barrier features had higher explanatory power in the more fragmented site, while facilitating features were important in the less fragmented site. Landscape models that included a simultaneous barrier and facilitating effect of roads had higher explanatory power than models that considered either effect separately, supporting the hypothesis that roads act as both barriers and facilitators at all spatial scales. The inclusion of LiDAR-identified shrubland habitat improved the fit of our facilitator models. Corridor analyses using circuit and least cost path approaches revealed the importance of anthropogenic, linear features for restoring connectivity between the study areas. In fragmented landscapes, human-modified habitats may enhance functional connectivity by providing suitable dispersal conduits for early successional specialists. PMID:26954014
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Modeling habitat split: landscape and life history traits determine amphibian extinction thresholds.
Fonseca, Carlos Roberto; Coutinho, Renato M; Azevedo, Franciane; Berbert, Juliana M; Corso, Gilberto; Kraenkel, Roberto A
2013-01-01
Habitat split is a major force behind the worldwide decline of amphibian populations, causing community change in richness and species composition. In fragmented landscapes, natural remnants, the terrestrial habitat of the adults, are frequently separated from streams, the aquatic habitat of the larvae. An important question is how this landscape configuration affects population levels and if it can drive species to extinction locally. Here, we put forward the first theoretical model on habitat split which is particularly concerned on how split distance - the distance between the two required habitats - affects population size and persistence in isolated fragments. Our diffusive model shows that habitat split alone is able to generate extinction thresholds. Fragments occurring between the aquatic habitat and a given critical split distance are expected to hold viable populations, while fragments located farther away are expected to be unoccupied. Species with higher reproductive success and higher diffusion rate of post-metamorphic youngs are expected to have farther critical split distances. Furthermore, the model indicates that negative effects of habitat split are poorly compensated by positive effects of fragment size. The habitat split model improves our understanding about spatially structured populations and has relevant implications for landscape design for conservation. It puts on a firm theoretical basis the relation between habitat split and the decline of amphibian populations.
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Analysis of the 1996 Wisconsin forest statistics by habitat type.
John Kotar; Joseph A. Kovach; Gary Brand
1999-01-01
The fifth inventory of Wisconsin's forests is presented from the perspective of habitat type as a classification tool. Habitat type classifies forests based on the species composition of the understory plant community. Various forest attributes are summarized by habitat type and management implications are discussed.
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Roberge, Jean-Michel; Öhman, Karin; Lämås, Tomas; Felton, Adam; Ranius, Thomas; Lundmark, Tomas; Nordin, Annika
2018-03-15
We evaluated the long-term implications from modifying rotation lengths in production forests for four forest-reliant species with different habitat requirements. By combining simulations of forest development with habitat models, and accounting both for stand and landscape scale influences, we projected habitat availability over 150 years in a large Swedish landscape, using rotation lengths which are longer (+22% and +50%) and shorter (-22%) compared to current practices. In terms of mean habitat availability through time, species requiring older forest were affected positively by extended rotations, and negatively by shortened rotations. For example, the mean habitat area for the treecreeper Certhia familiaris (a bird preferring forest with larger trees) increased by 31% when rotations were increased by 22%, at a 5% cost to net present value (NPV) and a 7% decrease in harvested volume. Extending rotation lengths by 50% provided more habitat for this species compared to a 22% extension, but at a much higher marginal cost. In contrast, the beetle Hadreule elongatula, which is dependent on sun-exposed dead wood, benefited from shortened rather than prolonged rotations. Due to an uneven distribution of stand-ages within the landscape, the relative amounts of habitat provided by different rotation length scenarios for a given species were not always consistent through time during the simulation period. If implemented as a conservation measure, prolonging rotations will require long-term strategic planning to avoid future bottlenecks in habitat availability, and will need to be accompanied by complementary measures accounting for the diversity of habitats necessary for the conservation of forest biodiversity. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Stopover habitat: management implications and guidelines
Frank R. Moore; Sidney A. Gauthreaux; Paul Kerlinger; Ted R. Simons
1993-01-01
If persistence of migrant populations depends on the ability to find favorable conditions for survival throughout the annual cycle, factors associated with the en-route ecology of migrants must figure in any analysis of population change and in development of a comprehensive conservation "strategy." We view en-route habitat selection as a hierarchical process...
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NASA Astrophysics Data System (ADS)
Vezza, Paolo; Comoglio, Claudio; Rosso, Maurizio
2010-05-01
oxygen were collected for each sampled area and considered as independent variables. According to the MesoHABSIM method, we performed a stepwise forward logistic regression in order to build up a biological model identifying the habitat characteristics mostly used by a target fish. For each stream we predicted changes in habitat area over a range of discharges by building the habitat-flow rating curves. Finally, in order to define a regional criteria needed to fulfill environmental flow requirements, we split the study domain according to the regression tree classification criterion defining homogenous sub-regions distinct on both environmental flows and catchment characteristics.
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Habitat suitability index models: Black crappie
Edwards, Elizabeth A.; Krieger, Douglas A.; Bacteller, Mary; Maughan, O. Eugene
1982-01-01
Characteristics and habitat requirements of the black crappie (Pomoxis nigromaculatus) are described in a review of Habitat Suitability Index models. This is one in a series of publications to provide information on the habitat requirements of selected fish and wildlife species. Numerous literature sources have been consulted in an effort to consolidate scientific data on species-habitat relationships. These data have subsequently been synthesized into explicit Habitat Suitability Index (HSI) models. The models are based on suitability indices indicating habitat preferences. Indices have been formulated for variables found to affect the life cycle and survival of each species. Habitat Suitability Index (HSI) models are designed to provide information for use in impact assessment and habitat management activities. The HSI technique is a corollary to the U.S. Fish and Wildlife Service's Habitat Evaluation Procedures.
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Habitat characteristics provide insights of carbon storage in seagrass meadows.
Mazarrasa, Inés; Samper-Villarreal, Jimena; Serrano, Oscar; Lavery, Paul S; Lovelock, Catherine E; Marbà, Núria; Duarte, Carlos M; Cortés, Jorge
2018-02-16
Seagrass meadows provide multiple ecosystem services, yet they are among the most threatened ecosystems on earth. Because of their role as carbon sinks, protection and restoration of seagrass meadows contribute to climate change mitigation. Blue Carbon strategies aim to enhance CO 2 sequestration and avoid greenhouse gasses emissions through the management of coastal vegetated ecosystems, including seagrass meadows. The implementation of Blue Carbon strategies requires a good understanding of the habitat characteristics that influence C org sequestration. Here, we review the existing knowledge on Blue Carbon research in seagrass meadows to identify the key habitat characteristics that influence C org sequestration in seagrass meadows, those factors that threaten this function and those with unclear effects. We demonstrate that not all seagrass habitats have the same potential, identify research priorities and describe the implications of the results found for the implementation and development of efficient Blue Carbon strategies based on seagrass meadows. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Owen, Sheldon F.; Berl, Jacob L.; Edwards, John W.; Ford, W. Mark; Wood, Petra Bohall
2015-01-01
We studied a raccoon (Procyon lotor) population within a managed central Appalachian hardwood forest in West Virginia to investigate the effects of intensive forest management on raccoon spatial requirements and habitat selection. Raccoon home-range (95% utilization distribution) and core-area (50% utilization distribution) size differed between sexes with males maintaining larger (2×) home ranges and core areas than females. Home-range and core-area size did not differ between seasons for either sex. We used compositional analysis to quantify raccoon selection of six different habitat types at multiple spatial scales. Raccoons selected riparian corridors (riparian management zones [RMZ]) and intact forests (> 70 y old) at the core-area spatial scale. RMZs likely were used by raccoons because they provided abundant denning resources (i.e., large-diameter trees) as well as access to water. Habitat composition associated with raccoon foraging locations indicated selection for intact forests, riparian areas, and regenerating harvest (stands <10 y old). Although raccoons were able to utilize multiple habitat types for foraging resources, a selection of intact forest and RMZs at multiple spatial scales indicates the need of mature forest (with large-diameter trees) for this species in managed forests in the central Appalachians.
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Oviedo, L; Solís, M
2008-06-01
Migrating humpback whales from northern and southern feeding grounds come to the tropical waters near Osa Peninsula, Pacific of Costa Rica, to reproduce and raise their calves. Planning effective marine protected areas that encompass humpback critical habitats require data about which oceanographic features influence distribution during the breeding period. This study examines the relationship between water depth and ocean floor slope with humpback whale distribution, based on sightings during two breeding seasons (2005 and 2006). Data are from the Southern and Northern subpopulations in the Eastern Tropical Pacific (ETP). Analysis followed the basic principles of the Ecological Niche Factors Analysis (ENFA), where indices of Marginality and Tolerance provide insights on the restrictiveness of habitat use. At a fine scale, physical factors such as water depth and slope define the critical breeding and nursing habitat for M. novaeangliae. Divergence in the subsamples means of depths and slope distribution, with the global mean of the study area in both eco-geographical variables, determine habitat requirements restricted by topographic features such as depths (< 100 m) and slope (< 10%), and locate the key breeding and nursing habitat of the species within the continental shelf domains. Proposed Marine Protected Areas (MPA's) network plans should consider connectivity of Cafio Island-Drake Bay and the extension of Corcovado National Park maritime borders.
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Wildlife Habitat Restoration: Chapter 12
Conway, Courtney J.; Borgmann, Kathi L.; Morrison, Michael L.; Mathewson, Heather A.
2015-01-01
As the preceding chapters point out, many wildlife species and the habitat they depend on are in peril. However, opportunities exist to restore habitat for many imperiled wildlife species. But what is wildlife habitat restoration? We begin this chapter by defining habitat restoration and then provide recommendations on how to maximize success of future habitat restoration efforts for wildlife. Finally, we evaluate whether we have been successful in restoring wildlife habitat and supply recommendations to advance habitat restoration. Successful restoration requires clear and explicit goals that are based on our best understanding of what the habitat was like prior to the disturbing event. Ideally, a restoration project would include: (1) a summary of prerestoration conditions that define the existing status of wildlife populations and their habitat; (2) a description of habitat features required by the focal or indicator species for persistence; (3) an a priori description of measurable, quantitative metrics that define restoration goals and measures of success; (4) a monitoring plan; (5) postrestoration comparisons of habitat features and wildlife populations with adjacent unmodified areas that are similar to the restoration site; and (6) expert review of the entire restoration plan (i.e., the five aforementioned components).
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Guidelines for managing lesser prairie-chicken populations and their habitats
Hagen, C.A.; Jamison, B.E.; Giesen, K.M.; Riley, T.Z.
2004-01-01
Lesser prairie-chicken (Tympanuchus pallidicinctus) populations have declined by >90% since the 1800s. These declines have concerned both biologists and private conservation groups and led to a petition to list the lesser prairie-chicken as threatened under the Endangered Species Act. Most of the land in the current range of the lesser prairie-chicken is privately owned, and declines have been primarily attributed to anthropogenic factors. Conversion of native rangeland to cropland and excessive grazing have been implicated as leading causes in the species' decline. Periodic drought probably has exacerbated these problems. Little research on habitat requirements was conducted prior to 1970. Despite recent advances in the knowledge of lesser prairie-chicken ecology, no comprehensive guidelines for management of the species have been published. In these guidelines, we provide a synopsis of our current knowledge of lesser prairie-chicken habitat requirements and suggest management strategies to monitor, maintain, and enhance lesser prairie-chicken populations.
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Habitat degradation may affect niche segregation patterns in lizards
NASA Astrophysics Data System (ADS)
Pelegrin, N.; Chani, J. M.; Echevarria, A. L.; Bucher, E. H.
2013-08-01
Lizards partition resources in three main niche dimensions: time, space and food. Activity time and microhabitat use are strongly influenced by thermal environment, and may differ between species according to thermal requirements and tolerance. As thermal characteristics are influenced by habitat structure, microhabitat use and activity of lizards can change in disturbed habitats. We compared activity and microhabitat use of two abundant lizard species of the Semi-arid Chaco of Argentina between a restored and a highly degraded Chaco forest, to determine how habitat degradation affects lizard segregation in time and space, hypothesizing that as activity and microhabitat use of lizards are related to habitat structure, activity and microhabitat use of individual species can be altered in degraded habitats, thus changing segregation patterns between them. Activity changed from an overlapped pattern in a restored forest to a segregated pattern in a degraded forest. A similar trend was observed for microhabitat use, although to a less extent. No correlation was found between air temperature and lizard activity, but lizard activity varied along the day and among sites. Contrary to what was believed, activity patterns of neotropical diurnal lizards are not fixed, but affected by multiple factors related to habitat structure and possibly to interspecific interactions. Changes in activity patterns and microhabitat use in degraded forests may have important implications when analyzing the effects of climate change on lizard species, due to synergistic effects.
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Barelli, Claudia; Albanese, Davide; Donati, Claudio; Pindo, Massimo; Dallago, Chiara; Rovero, Francesco; Cavalieri, Duccio; Michael Tuohy, Kieran; Christine Hauffe, Heidi; De Filippo, Carlotta
2015-01-01
The expansion of agriculture is shrinking pristine forest areas worldwide, jeopardizing the persistence of their wild inhabitants. The Udzungwa red colobus monkey (Procolobus gordonorum) is among the most threatened primate species in Africa. Primarily arboreal and highly sensitive to hunting and habitat destruction, they provide a critical model to understanding whether anthropogenic disturbance impacts gut microbiota diversity. We sampled seven social groups inhabiting two forests (disturbed vs. undisturbed) in the Udzungwa Mountains of Tanzania. While Ruminococcaceae and Lachnospiraceae dominated in all individuals, reflecting their role in extracting energy from folivorous diets, analysis of genus composition showed a marked diversification across habitats, with gut microbiota α-diversity significantly higher in the undisturbed forest. Functional analysis suggests that such variation may be associated with food plant diversity in natural versus human-modified habitats, requiring metabolic pathways to digest xenobiotics. Thus, the effects of changes in gut microbiota should not be ignored to conserve endangered populations. PMID:26445280
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NASA Astrophysics Data System (ADS)
Kidron, Giora J.; Starinsky, Abraham; Yaalon, Dan H.
2014-11-01
Although covering almost all rock outcrops around the world, little is known regarding the factors that govern the spatial distribution of lithic cyanobacteria and lichens. This is also the case in the Negev Desert, where cyanobacteria predominate on the rock outcrops of the south-facing slopes and lichens on the rock outcrops of the north-facing slopes. Hypothesizing that abiotic conditions determine their distribution, radiation, temperature, rain, dew and fog were monitored over a two-year period (2008-2010) at cyanobacteria- and lichen-dwelling habitats within a first-order drainage basin in the Negev Highlands. While non-significant differences characterized the rain amounts, substantial differences in substrate temperatures were recorded which resulted in turn in fundamental differences in the non-rainfall water regime. While dew condensed at the rock outcrops of the lichen habitat, no condensation took place at the cyanobacteria habitat. Contrary to the common belief, cyanobacteria were found to inhabit dewless habitats. As a result, cyanobacteria solely rely on rain precipitation for growth and can therefore serve as bioindicators for dewless habitats within the dewy Negev Desert. The findings may have important implications regarding Earth colonization, soil forming processes and geochemical processes following climate warming. They may explain lichen expansion and subsequent O2 increase during the mid Neoproterozoic providing indirect support for substantial photosynthetic activity and high weathering rates during this era.
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E. Questad; J.R. Kellner; K. Kinney; S. Cordell; G.P. Asner; J. Thaxton; J. Diep; A. Uowolo; S. Brooks; N. Inman-Narahari; S. Evans; B. Tucker
2014-01-01
The conservation of species at risk of extinction requires data to support decisions at landscape to regional scales. There is a need for information that can assist with locating suitable habitats in fragmented and degraded landscapes to aid the reintroduction of at-risk plant species. In addition, desiccation and water stress can be significant barriers to the...
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Quantifying terrestrial habitat loss and fragmentation: A protocol
Kevin McGarigal; Samuel Cushman; Claudia Regan
2005-01-01
Anthropogenic habitat loss and fragmentation have been implicated as among the key drivers of the burgeoning global biodiversity crisis. In response, there is a growing mandate among natural resource managers to evaluate the impacts of proposed management actions on the extent and fragmentation of habitats. Unfortunately, few guidelines exist to help managers...
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Does learning or instinct shape habitat selection?
Nielsen, Scott E; Shafer, Aaron B A; Boyce, Mark S; Stenhouse, Gordon B
2013-01-01
Habitat selection is an important behavioural process widely studied for its population-level effects. Models of habitat selection are, however, often fit without a mechanistic consideration. Here, we investigated whether patterns in habitat selection result from instinct or learning for a population of grizzly bears (Ursus arctos) in Alberta, Canada. We found that habitat selection and relatedness were positively correlated in female bears during the fall season, with a trend in the spring, but not during any season for males. This suggests that habitat selection is a learned behaviour because males do not participate in parental care: a genetically predetermined behaviour (instinct) would have resulted in habitat selection and relatedness correlations for both sexes. Geographic distance and home range overlap among animals did not alter correlations indicating that dispersal and spatial autocorrelation had little effect on the observed trends. These results suggest that habitat selection in grizzly bears are partly learned from their mothers, which could have implications for the translocation of wildlife to novel environments.
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NASA Astrophysics Data System (ADS)
Tang, Long; Gao, Yang; Wang, Cheng-Huan; Li, Bo; Chen, Jia-Kuan; Zhao, Bin
2013-07-01
Invasive species have to be managed to prevent adverse consequences. Spartina alterniflora has invaded many marshes where salinity and inundation are often key factors affecting vegetation. The former was surface clipped twice and native Phragmites australis was planted in invaded zones to examine the effects of habitat properties on the efficacy of invader control and native restoration. The results showed that two clipping treatments almost eliminated S. alterniflora in the zones with long inundation periods of 80 h/15 d but stimulated compensatory growth of S. alterniflora in the zones with short inundation periods. Transplanted P. australis performed better over time in zones with low salinity (<10.5 psu) but performed poorly in high-salinity zones, indicating that the efficacy of invader management and native restoration activities changes significantly along habitat gradients. With a progression from the dyke to the seaward side of the studied marsh, there was a long then short then long inundation period whereas salinity increased consistently. The study indicates that the high-frequency removal of the above-ground parts of S. alterniflora should be used only in the middle tidal zones and that native vegetation should be planted in zones above the mean high water level while the others zones in the saltmarsh should be restored to mud flats. Usually, invasive plants can flourish in highly heterogeneous habitats, which can influence management efficacy by influencing the re-growth of treated invaders and the performance of restored native species. Therefore, habitat-specific management regimes for invasive species can be expected to be more efficient because of their dependence on specific habitats.
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NASA Astrophysics Data System (ADS)
Ocock, J. F.; Bino, G.; Wassens, S.; Spencer, J.; Thomas, R. F.; Kingsford, R. T.
2018-03-01
Freshwater turtles face many threats, including habitat loss and river regulation reducing occupancy and contributing to population decline. Limited knowledge of hydrological conditions required to maintain viable turtle populations in large floodplain wetlands hinders effective adaptive management of environmental water in regulated rivers. We surveyed three turtle species over 4 years across the Lower Murrumbidgee River floodplain, a large wetland complex with a long history of water resource development. Using site and floodplain metrics and generalized linear models, within a Bayesian Model Averaging framework, we quantified the main drivers affecting turtle abundance. We also used a hierarchical modeling approach, requiring large sample sizes, quantifying possible environmental effects while accounting for detection probabilities of the eastern long-necked turtle ( Chelodina longicollis). The three species varied in their responses to hydrological conditions and connectivity to the main river channel. Broad-shelled turtles ( Chelodina expansa) and Macquarie River turtles ( Emydura macquarii macquarii) had restricted distributions, centered on frequently inundated wetlands close to the river, whereas the eastern long-necked turtles were more widely distributed, indicating an ability to exploit variable habitats. We conclude that turtle communities would benefit from long-term management strategies that maintain a spatiotemporal mosaic of hydrological conditions. More specifically, we identified characteristics of refuge habitats and stress the importance of maintaining their integrity during dry periods. Neighboring habitats can be targeted during increased water availability years to enhance feeding and dispersal opportunities for freshwater turtles.
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Habitat Suitability Index Models: Pronghorn
Allen, Arthur W.; Cook, John G.; Armbruster, Michael J.
1984-01-01
This is one of a series of publications that provide information on the habitat requirements of selected fish and wildlife species. Literature describing the relationship between habitat variables related to life requisites and habitat suitability for the pronghorn (Antilocapra americana) are synthesized. These data are subsequently used to develop Habitat Suitability Index (HSI) models. The HSI models are designed to provide information that can be used in impact assessment and habitat management.
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Functional variability of habitats within the Sacramento-San Joaquin Delta: Restoration implications
Lucas, L.V.; Cloern, J.E.; Thompson, J.K.; Monsen, N.E.
2002-01-01
We have now entered an era of large-scale attempts to restore ecological functions and biological communities in impaired ecosystems. Our knowledge base of complex ecosystems and interrelated functions is limited, so the outcomes of specific restoration actions are highly uncertain. One approach for exploring that uncertainty and anticipating the range of possible restoration outcomes is comparative study of existing habitats similar to future habitats slated for construction. Here we compare two examples of one habitat type targeted for restoration in the Sacramento-San Joaquin River Delta. We compare one critical ecological function provided by these shallow tidal habitats - production and distribution of phytoplankton biomass as the food supply to pelagic consumers. We measured spatial and short-term temporal variability of phytoplankton biomass and growth rate and quantified the hydrodynamic and biological processes governing that variability. Results show that the production and distribution of phytoplankton biomass can be highly variable within and between nearby habitats of the same type, due to variations in phytoplankton sources, sinks, and transport. Therefore, superficially similar, geographically proximate habitats can function very differently, and that functional variability introduces large uncertainties into the restoration process. Comparative study of existing habitats is one way ecosystem science can elucidate and potentially minimize restoration uncertainties, by identifying processes shaping habitat functionality, including those that can be controlled in the restoration design.
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Lopez, C.B.; Cloern, J.E.; Schraga, T.S.; Little, A.J.; Lucas, L.V.; Thompson, J.K.; Burau, J.R.
2006-01-01
A presumed value of shallow-habitat enhanced pelagic productivity derives from the principle that in nutrient-rich aquatic systems phytoplankton growth rate is controlled by light availability, which varies inversely with habitat depth. We measured a set of biological indicators across the gradient of habitat depth within the Sacramento-San Joaquin River Delta (California) to test the hypothesis that plankton biomass, production, and pelagic energy flow also vary systematically with habitat depth. Results showed that phytoplankton biomass and production were only weakly related to phytoplankton growth rates whereas other processes (transport, consumption) were important controls. Distribution of the invasive clam Corbicula fluminea was patchy, and heavily colonized habitats all supported low phytoplankton biomass and production and functioned as food sinks. Surplus primary production in shallow, uncolonized habitats provided potential subsidies to neighboring recipient habitats. Zooplankton in deeper habitats, where grazing exceeded phytoplankton production, were likely supported by significant fluxes of phytoplankton biomass from connected donor habitats. Our results provide three important lessons for ecosystem science: (a) in the absence of process measurements, derived indices provide valuable information to improve our mechanistic understanding of ecosystem function and to benefit adaptive management strategies; (b) the benefits of some ecosystem functions are displaced by water movements, so the value of individual habitat types can only be revealed through a regional perspective that includes connectedness among habitats; and (c) invasive species can act as overriding controls of habitat function, adding to the uncertainty of management outcomes. ?? 2006 Springer Science+Business Media, Inc.
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Daniel K. Rosenberg; Raymond J. Davis; Kelli J. Van Norman; Jeffrey R. Dunk; Eric D. Forsman; Robert D. Huff
2016-01-01
Environmental regulations often require wildlife surveys prior to habitat disturbance to avoid impacts or as the basis for planning mitigation, yet project-level surveys may not provide the insights needed to guide long-term management. Management of the red tree vole (Arborimus longicaudus) has largely been based on such surveys. As an alternative...
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Arkle, Robert S.; Pilliod, David S.; Hanser, Steven E.; Brooks, Matthew L.; Chambers, Jeanne C.; Grace, James B.; Knutson, Kevin C.; Pyke, David A.; Welty, Justin L.
2014-01-01
conditions, but in most climates, establishing forbs and reducing cheatgrass dominance is unlikely. Reestablishing sagebrush cover will require more than 20 years using past restoration methods. Given current fire frequencies and restoration capabilities, protection of landscapes containing a mix of dwarf sagebrush and big sagebrush steppe, minimal human development, and low non-native plant cover may provide the best opportunity for conservation of sage-grouse habitats.
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Habitat Suitability Index Models: Beaver
Allen, Arthur W.
1982-01-01
Habitat preferences of the beaver (Castor canadensis) are described in this publication, which is one of a series of Habitat Suitability Index (HSI) models. Habitat use information is presented in a synthesis of the literature on the species-habitat requirements of the beaver, followed by the development of the HSI model. The model is designed to provide information for use in impact assessment and habitat management activities, and should be used in conjunction with habitat evaluation procedures previously developed by the Fish and Wildlife Service. This revised model updates the original publication dated September 1982.
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Characterizing habitat suitability for a central-place forager in a dynamic marine environment.
Briscoe, Dana K; Fossette, Sabrina; Scales, Kylie L; Hazen, Elliott L; Bograd, Steven J; Maxwell, Sara M; McHuron, Elizabeth A; Robinson, Patrick W; Kuhn, Carey; Costa, Daniel P; Crowder, Larry B; Lewison, Rebecca L
2018-03-01
Characterizing habitat suitability for a marine predator requires an understanding of the environmental heterogeneity and variability over the range in which a population moves during a particular life cycle. Female California sea lions ( Zalophus californianus ) are central-place foragers and are particularly constrained while provisioning their young. During this time, habitat selection is a function of prey availability and proximity to the rookery, which has important implications for reproductive and population success. We explore how lactating females may select habitat and respond to environmental variability over broad spatial and temporal scales within the California Current System. We combine near-real-time remotely sensed satellite oceanography, animal tracking data ( n = 72) from November to February over multiple years (2003-2009) and Generalized Additive Mixed Models (GAMMs) to determine the probability of sea lion occurrence based on environmental covariates. Results indicate that sea lion presence is associated with cool ( <14°C ), productive waters, shallow depths, increased eddy activity, and positive sea-level anomalies. Predictive habitat maps generated from these biophysical associations suggest winter foraging areas are spatially consistent in the nearshore and offshore environments, except during the 2004-2005 winter, which coincided with an El Niño event. Here, we show how a species distribution model can provide broadscale information on the distribution of female California sea lions during an important life history stage and its implications for population dynamics and spatial management.
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Macdonald, Tara A; Burd, Brenda J; van Roodselaar, Albert
2012-01-01
Size distributions of biotic assemblages are important modifiers of productivity and function in marine sediments. We investigated the distribution of proportional organic biomass among logarithmic size classes (2(-6)J to 2(16)J) in the soft-bottom macrofaunal communities of the Strait of Georgia, Salish Sea on the west coast of Canada. The study examines how size structure is influenced by 3 fundamental habitat descriptors: depth, sediment percent fines, and organic flux (modified by quality). These habitat variables are uncorrelated in this hydrographically diverse area, thus we examine their effects in combination and separately. Cluster analyses and cumulative biomass size spectra reveal clear and significant responses to each separate habitat variable. When combined, habitat factors result in three distinct assemblages: (1) communities with a high proportion of biomass in small organisms, typical of shallow areas (<10 m) with coarse sediments (<10% fines) and low accumulation of organic material (<3.0 gC/m(2)/yr/δ(15)N); (2) communities with high proportion of biomass in the largest organisms found in the Strait, typical of deep, fine sediments with high modified organic flux (>3 g C/m(2)/yr/δ(15)N) from the Fraser River; and (3) communities with biomass dominated by moderately large organisms, but lacking the smallest and largest size classes, typical of deep, fine sediments experiencing low modified organic flux (<3.0 gC/m(2)/yr/δ(15)N). The remaining assemblages had intermediate habitat types and size structures. Sediment percent fines and flux appear to elicit threshold responses in size structure, whereas depth has the most linear influence on community size structure. The ecological implications of size structure in the Strait of Georgia relative to environmental conditions, secondary production and sediment bioturbation are discussed.
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Macdonald, Tara A.; Burd, Brenda J.; van Roodselaar, Albert
2012-01-01
Size distributions of biotic assemblages are important modifiers of productivity and function in marine sediments. We investigated the distribution of proportional organic biomass among logarithmic size classes (2−6J to 216J) in the soft-bottom macrofaunal communities of the Strait of Georgia, Salish Sea on the west coast of Canada. The study examines how size structure is influenced by 3 fundamental habitat descriptors: depth, sediment percent fines, and organic flux (modified by quality). These habitat variables are uncorrelated in this hydrographically diverse area, thus we examine their effects in combination and separately. Cluster analyses and cumulative biomass size spectra reveal clear and significant responses to each separate habitat variable. When combined, habitat factors result in three distinct assemblages: (1) communities with a high proportion of biomass in small organisms, typical of shallow areas (<10 m) with coarse sediments (<10% fines) and low accumulation of organic material (<3.0 gC/m2/yr/δ15N); (2) communities with high proportion of biomass in the largest organisms found in the Strait, typical of deep, fine sediments with high modified organic flux (>3 g C/m2/yr/δ15N) from the Fraser River; and (3) communities with biomass dominated by moderately large organisms, but lacking the smallest and largest size classes, typical of deep, fine sediments experiencing low modified organic flux (<3.0 gC/m2/yr/δ15N). The remaining assemblages had intermediate habitat types and size structures. Sediment percent fines and flux appear to elicit threshold responses in size structure, whereas depth has the most linear influence on community size structure. The ecological implications of size structure in the Strait of Georgia relative to environmental conditions, secondary production and sediment bioturbation are discussed. PMID:22911694
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NASA Habitat Demonstration Unit (HDU) Deep Space Habitat Analog
NASA Technical Reports Server (NTRS)
Howe, A. Scott; Kennedy, Kriss J.; Gill, Tracy
2013-01-01
The NASA Habitat Demonstration Unit (HDU) vertical cylinder habitat was established as a exploration habitat testbed platform for integration and testing of a variety of technologies and subsystems that will be required in a human-occupied planetary surface outpost or Deep Space Habitat (DSH). The HDU functioned as a medium-fidelity habitat prototype from 2010-2012 and allowed teams from all over NASA to collaborate on field analog missions, mission operations tests, and system integration tests to help shake out equipment and provide feedback for technology development cycles and crew training. This paper documents the final 2012 configuration of the HDU, and discusses some of the testing that took place. Though much of the higher-fidelity functionality has 'graduated' into other NASA programs, as of this writing the HDU, renamed Human Exploration Research Analog (HERA), will continue to be available as a volumetric and operational mockup for NASA Human Research Program (HRP) research from 2013 onward.
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Predictive Seagrass Habitat Model
Restoration of ecosystem services provided by seagrass habitats in estuaries requires a firm understanding of the modes of action of multiple interacting stressors including nutrients, climate change, coastal land-use change, and habitat modification. We explored the application...
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Lunar Habitat Optimization Using Genetic Algorithms
NASA Technical Reports Server (NTRS)
SanScoucie, M. P.; Hull, P. V.; Tinker, M. L.; Dozier, G. V.
2007-01-01
Long-duration surface missions to the Moon and Mars will require bases to accommodate habitats for the astronauts. Transporting the materials and equipment required to build the necessary habitats is costly and difficult. The materials chosen for the habitat walls play a direct role in protection against each of the mentioned hazards. Choosing the best materials, their configuration, and the amount required is extremely difficult due to the immense size of the design region. Clearly, an optimization method is warranted for habitat wall design. Standard optimization techniques are not suitable for problems with such large search spaces; therefore, a habitat wall design tool utilizing genetic algorithms (GAs) has been developed. GAs use a "survival of the fittest" philosophy where the most fit individuals are more likely to survive and reproduce. This habitat design optimization tool is a multiobjective formulation of up-mass, heat loss, structural analysis, meteoroid impact protection, and radiation protection. This Technical Publication presents the research and development of this tool as well as a technique for finding the optimal GA search parameters.
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Habitat evaluation for outbreak of Yangtze voles (Microtus fortis) and management implications.
Xu, Zhenggang; Zhao, Yunlin; Li, Bo; Zhang, Meiwen; Shen, Guo; Wang, Yong
2015-05-01
Rodent pests severely damage agricultural crops. Outbreak risk models of rodent pests often do not include sufficient information regarding geographic variation. Habitat plays an important role in rodent-pest outbreak risk, and more information about the relationship between habitat and crop protection is urgently needed. The goal of the present study was to provide an outbreak risk map for the Dongting Lake region and to understand the relationship between rodent-pest outbreak variation and habitat distribution. The main rodent pests in the Dongting Lake region are Yangtze voles (Microtus fortis). These pests cause massive damage in outbreak years, most notably in 2007. Habitat evaluation and ecological details were obtained by analyzing the correlation between habitat suitability and outbreak risk, as indicated by population density and historical events. For the source-sink population, 96.18% of Yangtze vole disaster regions were covered by a 10-km buffer zone of suitable habitat in 2007. Historical outbreak frequency and peak population density were significantly correlated with the proportion of land covered by suitable habitat (r = 0.68, P = 0.04 and r = 0.76, P = 0.03, respectively). The Yangtze vole population tends to migrate approximately 10 km in outbreak years. Here, we propose a practical method for habitat evaluation that can be used to create integrated pest management plans for rodent pests when combined with basic information on the biology, ecology and behavior of the target species. © 2014 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.
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Habitat Suitability Index Models: Veery
Sousa, Patrick J.
1982-01-01
Habitat preferences and species characteristics of the veery (Catharus fuscesens) are described in this publication. It is one of a series of Habitat Suitability Index (HSI) models and was developed through an analysis of available scientific data on the habitat requirements of the veery. Habitat use information is presented in a review of the literature, followed by the development of an HSI model. The model is presented in three formats: graphic; word; and mathematical. Suitability index graphs quantify the species-habitat relationship. These data are synthesized into a model designed to provide information for use in impact assessment and habitat management.
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Banerjee, Soumyajit; Mohan, Sushree; Saha, Nabaneeta; Mohanty, Siba Prasad; Saha, Goutam K; Aditya, Gautam
2015-12-01
The quality of breeding sites is reflected through the pupal productivity and the life history traits of Aedes mosquitoes. Using nutrient reserves and pupal productivity of Aedes as indicators, the larval habitats including sewage drains were characterized to highlight the habitat expansion and vector management. The pupae and adults collected from the containers and sewage drains were characterized in terms of biomass and nutrient reserves and the data were subjected to three way factorial ANOVA. Discriminant function analyses were performed to highlight the differences among the habitats for sustenance of Aedes mosquitoes. Survey of larval habitats from the study area revealed significant differences (P<0.05) in the pupal productivity of Aedes among the habitats and months. Despite sewage drains being comparatively less utilized for breeding, the pupae were of higher biomass with corresponding adults having longer wings in contrast to other habitats. The nutrient reserve of the adults emerging from pupae of sewage drains was significantly higher (P<0.05), compared to other habitats, as reflected through the discriminant function analysis. The present results showed that for both Ae. aegypti and Ae. albopictus, sewage drains were equally congenial habitat as were plastic, porcelain and earthen habitats. Availability of Aedes immature in sewage drains poses increased risk of dengue, and thus vector control programme should consider inclusion of sewage drains as breeding habitat of dengue vector mosquitoes.
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Does Learning or Instinct Shape Habitat Selection?
Nielsen, Scott E.; Shafer, Aaron B. A.; Boyce, Mark S.; Stenhouse, Gordon B.
2013-01-01
Habitat selection is an important behavioural process widely studied for its population-level effects. Models of habitat selection are, however, often fit without a mechanistic consideration. Here, we investigated whether patterns in habitat selection result from instinct or learning for a population of grizzly bears (Ursus arctos) in Alberta, Canada. We found that habitat selection and relatedness were positively correlated in female bears during the fall season, with a trend in the spring, but not during any season for males. This suggests that habitat selection is a learned behaviour because males do not participate in parental care: a genetically predetermined behaviour (instinct) would have resulted in habitat selection and relatedness correlations for both sexes. Geographic distance and home range overlap among animals did not alter correlations indicating that dispersal and spatial autocorrelation had little effect on the observed trends. These results suggest that habitat selection in grizzly bears are partly learned from their mothers, which could have implications for the translocation of wildlife to novel environments. PMID:23341983
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Habitat Design Optimization and Analysis
NASA Technical Reports Server (NTRS)
SanSoucie, Michael P.; Hull, Patrick V.; Tinker, Michael L.
2006-01-01
Long-duration surface missions to the Moon and Mars will require habitats for the astronauts. The materials chosen for the habitat walls play a direct role in the protection against the harsh environments found on the surface. Choosing the best materials, their configuration, and the amount required is extremely difficult due to the immense size of the design region. Advanced optimization techniques are necessary for habitat wall design. Standard optimization techniques are not suitable for problems with such large search spaces; therefore, a habitat design optimization tool utilizing genetic algorithms has been developed. Genetic algorithms use a "survival of the fittest" philosophy, where the most fit individuals are more likely to survive and reproduce. This habitat design optimization tool is a multi-objective formulation of structural analysis, heat loss, radiation protection, and meteoroid protection. This paper presents the research and development of this tool.
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Habitat fragmentation and interspecific competition: Implications for lynx conservation [Chapter 4
Steven W. Buskirk
2000-01-01
Habitat fragmentation and interspecific competition are two important forces that potentially affect lynx populations. Fragmentation operates by various mechanisms, including direct habitat loss, vehicle collisions and behavioral disturbance from roads, and changes in landscape features such as edges. Competition takes two forms: Exploitation competition involves...
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Habitat Suitability Index Models: Marten
Allen, Arthur W.
1982-01-01
Habitat preferences and species characteristics of the pine marten (Martes americana) are described in this publication. It is one of a series of Habitat Suitability Index (HSI) models and was developed through an analysis of available scientific data on the species-habitat requirements of the pine marten. Habitat use information is presented in a review of the literature, followed by the development of a HSI model. The model is presented in three formats: graphic, word and mathematical. Suitability index graphs quantify the species-habitat relationship. These data are then synthesized into a model which is designed to provide information for use in impact assessment and habitat management activities.
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Phillipsen, Ivan C; Kirk, Emily H; Bogan, Michael T; Mims, Meryl C; Olden, Julian D; Lytle, David A
2015-01-01
Species occupying the same geographic range can exhibit remarkably different population structures across the landscape, ranging from highly diversified to panmictic. Given limitations on collecting population-level data for large numbers of species, ecologists seek to identify proximate organismal traits-such as dispersal ability, habitat preference and life history-that are strong predictors of realized population structure. We examined how dispersal ability and habitat structure affect the regional balance of gene flow and genetic drift within three aquatic insects that represent the range of dispersal abilities and habitat requirements observed in desert stream insect communities. For each species, we tested for linear relationships between genetic distances and geographic distances using Euclidean and landscape-based metrics of resistance. We found that the moderate-disperser Mesocapnia arizonensis (Plecoptera: Capniidae) has a strong isolation-by-distance pattern, suggesting migration-drift equilibrium. By contrast, population structure in the flightless Abedus herberti (Hemiptera: Belostomatidae) is influenced by genetic drift, while gene flow is the dominant force in the strong-flying Boreonectes aequinoctialis (Coleoptera: Dytiscidae). The best-fitting landscape model for M. arizonensis was based on Euclidean distance. Analyses also identified a strong spatial scale-dependence, where landscape genetic methods only performed well for species that were intermediate in dispersal ability. Our results highlight the fact that when either gene flow or genetic drift dominates in shaping population structure, no detectable relationship between genetic and geographic distances is expected at certain spatial scales. This study provides insight into how gene flow and drift interact at the regional scale for these insects as well as the organisms that share similar habitats and dispersal abilities. © 2014 John Wiley & Sons Ltd.
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Jacobson, R.B.
2013-01-01
strategies requires that the role of physical habitat is correctly diagnosed and that restoration activities address true habitat limitations, including the role of dynamic habitats.
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Habitat Suitability Index Models: Eastern meadowlark
Schroeder, Richard L.; Sousa, Patrick J.
1982-01-01
Habitat preferences of the eastern meadowlark (Sturnella magna) are described in this publication, which is one of a series of Habitat Suitability Index (HSI) models. Habitat use information is presented in a synthesis of the literature on the species-habitat requirements of the eastern meadowlark, followed by the development of the HSI model. The model is presented in three formats: graphic, word, and mathematical, and is designed to provide information for use in impact assessment and habitat management activities.
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Habitat Suitability Index Models: Pine warbler
Schroeder, Richard L.
1982-01-01
Habitat preferences of the pine warbler (Dendroica pinus) are described in this publication, which is one of a series of Habitat Suitability Index (HSI) models. Habitat use information is presented in a synthesis of the literature on the species-habitat requirements of the pine warbler, followed by the development of the HSI model. The model is presented in three formats: graphic, word, and mathematical, and is designed to provide information for use in impact assessment and habitat management activities.
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No net loss of fish habitat: a review and analysis of habitat compensation in Canada.
Harper, D J; Quigley, J T
2005-09-01
The achievement of No Net Loss (NNL) through habitat compensation has rarely been assessed in Canada. Files relating to 124 Fisheries Act Section 35(2) authorizations issued by Fisheries and Oceans Canada for the harmful alteration, disruption, and destruction of fish habitat (HADD) were collected and reviewed. Data extracted from these files were pooled and analyzed to provide an indication of the types of HADDs that have been authorized in Canada, what habitats have been affected, and what habitat management approaches have been used when compensating for HADDs and monitoring and ensuring the success of the compensation. Determinations regarding the effectiveness of habitat compensation in achieving NNL were made. Impacts to 419,562 m2 of fish habitat from the 124 authorized HADDs were offset by 1,020,388 m2 of compensatory habitat. Eighty percent of the authorizations had compensation ratios (compensation area:HADD area) of 2:1 or less, and 25% of the authorizations had a compensation ratio that was less than 1:1. In-channel and riparian habitat were the most frequently impacted habitats. Urban development and roads and highways resulted in the greatest areal loss of habitat. The compensation option that was most often selected was the creation of in-kind habitat. The mean duration of post-construction monitoring programs was 3.7 years. Determinations of NNL could only be made for 17 authorizations as a result of poor proponent compliance with monitoring requirements and the qualitative assessment procedures used by the monitoring programs. Adequate resources, proper training, and standardized approaches to data management and monitoring programs are required to ensure that the conservation goal of NNL can be achieved in Canada.
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Soares, Leiza Aparecida S S; Faria, Deborah; Vélez-Garcia, Felipe; Vieira, Emerson M; Talora, Daniela C; Cazetta, Eliana
2015-01-01
Habitat loss is the main driver of the loss of global biodiversity. Knowledge on this subject, however, is highly concentrated on species richness and composition patterns, with little discussion on the consequences of habitat loss for ecological interactions. Therefore, a systemic approach is necessary to maximize the success of conservation efforts by providing more realistic information about the effects of anthropogenic disturbances on natural environmental processes. We investigated the implications of habitat loss for the early recruitment of Euterpe edulis Martius, a keystone palm in the Brazilian Atlantic Forest, in nine sampling sites located in landscapes with different percentages of forest cover (9%-83%). We conducted a paired experiment using E. Edulis seeds set up in experimental stations composed of a vertebrate exclosure versus an open treatment. We used ANCOVA models with treatments as factors to assess the influence of habitat loss on the number of germinated seeds, predation by vertebrates and invertebrates, infestation by fungi, and number of seedlings established. Habitat loss did not affect the probability of transition from a dispersed to a germinated seed. However, when seeds were protected from vertebrate removal, seedling recruitment showed a positive relationship with the amount of forest cover. Seed infestation by fungi was not significant, and seed predation was the main factor limiting seed recruitment. The loss of forest cover antagonistically affected the patterns of seed predation by vertebrates and invertebrates; predation by invertebrates was higher in less forested areas, and predation by vertebrates was higher in forested areas. When seeds were exposed to the action of all biotic mortality factors, the number of recruited seedlings was very low and unrelated to habitat loss. This result indicates that the opposite effects of seed predation by vertebrates and invertebrates mask a differential response of E. edulis recruitment to
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Soares, Leiza Aparecida S. S.; Faria, Deborah; Vélez-Garcia, Felipe; Vieira, Emerson M.; Talora, Daniela C.; Cazetta, Eliana
2015-01-01
Habitat loss is the main driver of the loss of global biodiversity. Knowledge on this subject, however, is highly concentrated on species richness and composition patterns, with little discussion on the consequences of habitat loss for ecological interactions. Therefore, a systemic approach is necessary to maximize the success of conservation efforts by providing more realistic information about the effects of anthropogenic disturbances on natural environmental processes. We investigated the implications of habitat loss for the early recruitment of Euterpe edulis Martius, a keystone palm in the Brazilian Atlantic Forest, in nine sampling sites located in landscapes with different percentages of forest cover (9%-83%). We conducted a paired experiment using E. Edulis seeds set up in experimental stations composed of a vertebrate exclosure versus an open treatment. We used ANCOVA models with treatments as factors to assess the influence of habitat loss on the number of germinated seeds, predation by vertebrates and invertebrates, infestation by fungi, and number of seedlings established. Habitat loss did not affect the probability of transition from a dispersed to a germinated seed. However, when seeds were protected from vertebrate removal, seedling recruitment showed a positive relationship with the amount of forest cover. Seed infestation by fungi was not significant, and seed predation was the main factor limiting seed recruitment. The loss of forest cover antagonistically affected the patterns of seed predation by vertebrates and invertebrates; predation by invertebrates was higher in less forested areas, and predation by vertebrates was higher in forested areas. When seeds were exposed to the action of all biotic mortality factors, the number of recruited seedlings was very low and unrelated to habitat loss. This result indicates that the opposite effects of seed predation by vertebrates and invertebrates mask a differential response of E. edulis recruitment to
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Dorava, J.M.; Milner, A.M.
1999-01-01
Numerous drainages supporting productive salmon habitat are surrounded by active volcanoes on the west side of Cook Inlet in south-central Alaska. Eruptions have caused massive quantities of flowing water and sediment to enter the river channels emanating from glaciers and snowfields on these volcanoes. Extensive damage to riparian and aquatic habitat has commonly resulted, and benthic macroinvertebrate and salmonid communities can be affected. Because of the economic importance of Alaska's fisheries, detrimental effects on salmonid habitat can have significant economic implications. The Drift River drains glaciers on the northern and eastern flanks of Redoubt Volcano: During and following eruptions in 1989-1990, severe physical disturbances to the habitat features of the river adversely affected the fishery. Frequent eruptions at other Cook Inlet region volcanoes exemplify the potential effects of volcanic activity on Alaska's important commercial, sport, and subsistence fisheries. Few studies have documented the recovery of aquatic habitat following volcanic eruptions. The eruptions of Redoubt Volcano in 1989-1990 offered an opportunity to examine the recovery of the macroinvertebrate community. Macroinvertebrate community composition and structure in the Drift River were similar in both undisturbed and recently disturbed sites. Additionally, macroinvertebrate samples from sites in nearby undisturbed streams were highly similar to those from some Drift River sites. This similarity and the agreement between the Drift River macroinvertebrate community composition and that predicted by a qualitative model of typical macroinvertebrate communities in glacier-fed rivers indicate that the Drift River macroinvertebrate community is recovering five years after the disturbances associated with the most recent eruptions of Redoubt Volcano.
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Implications of scale-independent habitat specialization on persistence of a rare small mammal
Cleaver, Michael; Klinger, Robert C.; Anderson, Steven T.; Maier, Paul A.; Clark, Jonathan
2015-01-01
We assessed the habitat use patterns of the Amargosa vole Microtus californicus scirpensis , an endangered rodent endemic to wetland vegetation along a 3.5 km stretch of the Amargosa River in the Mojave Desert, USA. Our goals were to: (1) quantify the vole’s abundance, occupancy rates and habitat selection patterns along gradients of vegetation cover and spatial scale; (2) identify the processes that likely had the greatest influence on its habitat selection patterns. We trapped voles monthly in six 1 ha grids from January to May 2012 and measured habitat structure at subgrid (View the MathML source225m2) and trap (View the MathML source1m2) scales in winter and spring seasons. Regardless of scale, analyses of density, occupancy and vegetation structure consistently indicated that voles occurred in patches of bulrush (Schoenoplectus americanus ; Cyperaceae) where cover >50%. The majority of evidence indicates the vole's habitat selectivity is likely driven by bulrush providing protection from intense predation. However, a combination of selective habitat use and limited movement resulted in a high proportion of apparently suitable bulrush patches being unoccupied. This suggests the Amargosa vole's habitat selection behavior confers individual benefits but may not allow the overall population to persist in a changing environment.
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K.M. Burnett; G.H. Reeves; D.J. Miller; S. Clarke; K. Vance-Borland; K. Christiansen
2007-01-01
The geographic distribution of stream reaches with potential to support high-quality habitat for salmonids has bearing on the actual status of habitats and populations over broad spatial extents. As part of the Coastal Landscape Analysis and Modeling Study, we examined how salmon-habitat potential was distributed relative to current and future (+100 years) landscape...
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DORAVA; MILNER
1999-02-01
/ Numerous drainages supporting productive salmon habitat are surrounded by active volcanoes on the west side of Cook Inlet in south-central Alaska. Eruptions have caused massive quantities of flowing water and sediment to enter the river channels emanating from glaciers and snowfields on these volcanoes. Extensive damage to riparian and aquatic habitat has commonly resulted, and benthic macroinvertebrate and salmonid communities can be affected. Because of the economic importance of Alaska's fisheries, detrimental effects on salmonid habitat can have significant economic implications. The Drift River drains glaciers on the northern and eastern flanks of Redoubt Volcano. During and following eruptions in 1989-1990, severe physical disturbances to the habitat features of the river adversely affected the fishery. Frequent eruptions at other Cook Inlet region volcanoes exemplify the potential effects of volcanic activity on Alaska's important commercial, sport, and subsistence fisheries. Few studies have documented the recovery of aquatic habitat following volcanic eruptions. The eruptions of Redoubt Volcano in 1989-1990 offered an opportunity to examine the recovery of the macroinvertebrate community. Macroinvertebrate community composition and structure in the Drift River were similar in both undisturbed and recently disturbed sites. Additionally, macroinvertebrate samples from sites in nearby undisturbed streams were highly similar to those from some Drift River sites. This similarity and the agreement between the Drift River macroinvertebrate community composition and that predicted by a qualitative model of typical macroinvertebrate communities in glacier-fed rivers indicate that the Drift River macroinvertebrate community is recovering five years after the disturbances associated with the most recent eruptions of Redoubt Volcano. KEY WORDS: Aquatic habitat; Volcanoes; Lahars; Lahar-runout flows; Macroinvertebrates; Community structure; Community composition
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Armstrong, David S.; Parker, Gene W.; Richards, Todd A.
2003-01-01
Streamflow characteristics and methods for determining streamflow requirements for habitat protection were investigated at 23 active index streamflow-gaging stations in southern New England. Fish communities sampled near index streamflow-gaging stations in Massachusetts have a high percentage of fish that require flowing-water habitats for some or all of their life cycle. The relatively unaltered flow condition at these sites was assumed to be one factor that has contributed to this condition. Monthly flow durations and low flow statistics were determined for the index streamflow-gaging stations for a 25- year period from 1976 to 2000. Annual hydrographs were prepared for each index station from median streamflows at the 50-percent monthly flow duration, normalized by drainage area. A median monthly flow of 1 ft3/s/mi2 was used to split hydrographs into a high-flow period (November–May), and a low-flow period (June–October). The hydrographs were used to classify index stations into groups with similar median monthly flow durations. Index stations were divided into four regional groups, roughly paralleling the coast, to characterize streamflows for November to May; and into two groups, on the basis of base-flow index and percentage of sand and gravel in the contributing area, for June to October. For the June to October period, for index stations with a high base-flow index and contributing areas greater than 20 percent sand and gravel, median streamflows at the 50-percent monthly flow duration, normalized by drainage area, were 0.57, 0.49, and 0.46 ft3/s/mi2 for July, August, and September, respectively. For index stations with a low base-flow index and contributing areas less than 20 percent sand and gravel, median streamflows at the 50-percent monthly flow duration, normalized by drainage area, were 0.34, 0.28, and 0.27 ft3/s/mi2 for July, August, and September, respectively. Streamflow variability between wet and dry years can be characterized by use of the
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Loss and modification of habitat
Lemckert, Francis; Hecnar, Stephen; Pilliod, David S.; Wilkinson, John W.; Heatwole, Harold
2012-01-01
Amphibians live in a wide variety of habitats around the world, many of which have been modified or destroyed by human activities. Most species have unique life history characteristics adapted to specific climates, habitats (e.g., lentic, lotic, terrestrial, arboreal, fossorial, amphibious), and local conditions that provide suitable areas for reproduction, development and growth, shelter from environmental extremes, and predation, as well as connectivity to other populations or habitats. Although some species are entirely aquatic or terrestrial, most amphibians, as their name implies, lead a dual life and require a mosaic of habitats in both aquatic and terrestrial ecosystems. With over 6 billion people on Earth, most species are now persisting in habitats that have been directly or indirectly influenced by human activities. Some species have disappeared where their habitats have been completely destroyed, reduced, or rendered unsuitable. Habitat loss and degradation are widely considered by most researchers as the most important causes of amphibian population decline globally (Barinaga 1990; Wake and Morowitz 1991; Alford and Richards 1999). In this chapter, a background on the diverse habitat requirements of amphibians is provided, followed by a discussion of the effects of urbanization, agriculture, livestock grazing, timber production and harvesting, fire and hazardous fuel management, and roads on amphibians and their habitats. Also briefly discussed is the influence on amphibian habitats of natural disturbances, such as extreme weather events and climate change, given the potential for human activities to impact climate in the longer term. For amphibians in general, microhabitats are of greater importance than for other vertebrates. As ectotherms with a skin that is permeable to water and with naked gelatinous eggs, amphibians are physiologically constrained to be active during environmental conditions that provide appropriate body temperatures and adequate
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Pindilli, Emily J.; Casey, Frank
2015-10-26
This report is a primer on market-like and market-based mechanisms designed to conserve biodiversity and habitat. The types of markets and market-based approaches that were implemented or are emerging to benefit biodiversity and habitat in the United States are examined. The central approaches considered in this report include payments for ecosystem services, conservation banks, habitat exchanges, and eco-labels. Based on literature reviews and input from experts and practitioners, the report characterizes each market-based approach including policy context and structure; the theoretical basis for applying market-based approaches; the ecological effectiveness of practices and tools for measuring performance; and the future outlook for biodiversity and habitat markets. This report draws from previous research and serves as a summary of pertinent information associated with biodiversity and habitat markets while providing references to materials that go into greater detail on specific topics.
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Habitat Suitability Index Models: Yellow-headed blackbird
Schroeder, Richard L.
1982-01-01
Habitat preferences of the yellow-headed blackbird (Xanthocephalus xanthocephalus) are described in this publication. It is one of a series of Habitat Suitability Index (HSI) models and was developed through an analysis of available infomration on the species-habitat requirements of the species. Habitat use information is presented in a review of the literature, followed by the development of an HSI model, designed for use in impact assessment and habitat management activities.
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Resource use of Japanese macaques in heavy snowfall areas: implications for habitat management.
Enari, Hiroto; Sakamaki-Enari, Haruka
2013-07-01
Populations of Japanese macaque (Macaca fuscata) that inhabit the northernmost distribution of any nonhuman primates have been listed as endangered in Japan; however, macaques are widely known for being pests that cause agricultural damage. This study identified priority areas for the conservation and management of macaque habitats, by comparing the resource use of troops occupying remote mountains (montane troops) against troops inhabiting disturbed forests adjacent to settlements (rural troops). We collected species presence data across 2 years by radio-tracking two montane troops and two rural troops in the Shirakami Mountains. We developed seasonal utilization distributions by using the kernel method, and identified habitat characteristics by using ecological-niche factor analysis (ENFA). Our results indicate that environmental factors influencing the potential habitat varied widely with season in montane troops as compared with that in rural troops. ENFA results demonstrated that rural troops exhibited more biased resource use and narrower niche breadths than montane troops. Based on our findings, we propose that (1) primary broadleaf forests are the spring habitat conservation priority of montane troops; (2) the habitat unit--the product of habitat suitability index and its surface area--for montane troops is enhanced by removing old conifer plantations from the forest edge at low elevations; (3) such removal around settlements may also contribute toward removing a frontline refuge for rural troops intruding farmlands; and (4) intensive prevention measures against macaque intrusions into settlements during the bottleneck snowy season contribute toward reducing the habitat unit of rural troops.
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Habitat Use and Selection by Giant Pandas.
Hull, Vanessa; Zhang, Jindong; Huang, Jinyan; Zhou, Shiqiang; Viña, Andrés; Shortridge, Ashton; Li, Rengui; Liu, Dian; Xu, Weihua; Ouyang, Zhiyun; Zhang, Hemin; Liu, Jianguo
2016-01-01
Animals make choices about where to spend their time in complex and dynamic landscapes, choices that reveal information about their biology that in turn can be used to guide their conservation. Using GPS collars, we conducted a novel individual-based analysis of habitat use and selection by the elusive and endangered giant pandas (Ailuropoda melanoleuca). We constructed spatial autoregressive resource utilization functions (RUF) to model the relationship between the pandas' utilization distributions and various habitat characteristics over a continuous space across seasons. Results reveal several new insights, including use of a broader range of habitat characteristics than previously understood for the species, particularly steep slopes and non-forest areas. We also used compositional analysis to analyze habitat selection (use with respect to availability of habitat types) at two selection levels. Pandas selected against low terrain position and against the highest clumped forest at the at-home range level, but no significant factors were identified at the within-home range level. Our results have implications for modeling and managing the habitat of this endangered species by illustrating how individual pandas relate to habitat and make choices that differ from assumptions made in broad scale models. Our study also highlights the value of using a spatial autoregressive RUF approach on animal species for which a complete picture of individual-level habitat use and selection across space is otherwise lacking.
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Habitat Use and Selection by Giant Pandas
Hull, Vanessa; Zhang, Jindong; Huang, Jinyan; Zhou, Shiqiang; Viña, Andrés; Shortridge, Ashton; Li, Rengui; Liu, Dian; Xu, Weihua; Ouyang, Zhiyun; Zhang, Hemin; Liu, Jianguo
2016-01-01
Animals make choices about where to spend their time in complex and dynamic landscapes, choices that reveal information about their biology that in turn can be used to guide their conservation. Using GPS collars, we conducted a novel individual-based analysis of habitat use and selection by the elusive and endangered giant pandas (Ailuropoda melanoleuca). We constructed spatial autoregressive resource utilization functions (RUF) to model the relationship between the pandas' utilization distributions and various habitat characteristics over a continuous space across seasons. Results reveal several new insights, including use of a broader range of habitat characteristics than previously understood for the species, particularly steep slopes and non-forest areas. We also used compositional analysis to analyze habitat selection (use with respect to availability of habitat types) at two selection levels. Pandas selected against low terrain position and against the highest clumped forest at the at-home range level, but no significant factors were identified at the within-home range level. Our results have implications for modeling and managing the habitat of this endangered species by illustrating how individual pandas relate to habitat and make choices that differ from assumptions made in broad scale models. Our study also highlights the value of using a spatial autoregressive RUF approach on animal species for which a complete picture of individual-level habitat use and selection across space is otherwise lacking. PMID:27627805
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Physical habitat in the national wadeable streams assessment
Effective environmental policy decisions require stream habitat information that is accurate, precise, and relevant. The recent National Wadeable Streams Assessment (NWSA) carried out by the U.S. EPA required physical habitat information sufficiently comprehensive to facilitate i...
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Sogge, M.K.; Sferra, S.J.; Paxton, E.H.
2008-01-01
Exotic vegetation has become a major habitat component in many ecosystems around the world, sometimes dramatically changing the vegetation community structure and composition. In the southwestern United States, riparian ecosystems are undergoing major changes in part due to the establishment and spread of the exotic Tamarix (saltcedar, tamarisk). There are concerns about the suitability of Tamarix as habitat for birds. Although Tamarix habitats tend to support fewer species and individuals than native habitats, Arizona Breeding Bird Atlas data and Birds of North America accounts show that 49 species use Tamarix as breeding habitat. Importantly, the relative use of Tamarix and its quality as habitat vary substantially by geographic location and bird species. Few studies have examined how breeding in Tamarix actually affects bird survivorship and productivity; recent research on Southwestern Willow Flycatchers has found no negative effects from breeding in Tamarix habitats. Therefore, the ecological benefits and costs of Tamarix control are difficult to predict and are likely to be species specific and site specific. Given the likelihood that high-quality native riparian vegetation will not develop at all Tamarix control sites, restoration projects that remove Tamarix but do not assure replacement by high-quality native habitat have the potential to reduce the net riparian habitat value for some local or regional bird populations. Therefore, an assessment of potential negative impacts is important in deciding if exotic control should be conducted. In addition, measurable project objectives, appropriate control and restoration techniques, and robust monitoring are all critical to effective restoration planning and execution. ?? 2008 Society for Ecological Restoration International.
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A Synopsis of Global Mapping of Freshwater Habitats and Biodiversity: Implications for Conservation
DOE Office of Scientific and Technical Information (OSTI.GOV)
McManamay, Ryan A.; Griffiths, Natalie A.; DeRolph, Christopher R.
Accurately mapping freshwater habitats and biodiversity at high-resolutions across the globe is essential for assessing the vulnerability and threats to freshwater organisms and prioritizing conservation efforts. Since the 2000s, extensive efforts have been devoted to mapping global freshwater habitats (rivers, lakes, and wetlands), the spatial representation of which has changed dramatically over time with new geospatial data products and improved remote sensing technologies. Some of these mapping efforts, however, are still coarse representations of actual conditions. Likewise, the resolution and scope of global freshwater biodiversity compilation efforts have also increased, but are yet to mirror the spatial resolution and fidelitymore » of mapped freshwater environments. In our synopsis, we find that efforts to map freshwater habitats have been conducted independently of those for freshwater biodiversity; subsequently, there is little congruence in the spatial representation and resolution of the two efforts. We suggest that global species distribution models are needed to fill this information gap; however, limiting data on habitat characteristics at scales that complement freshwater habitats has prohibited global high-resolution biogeography efforts. Emerging research trends, such as mapping habitat alteration in freshwater ecosystems and trait biogeography, show great promise in mechanistically linking global anthropogenic stressors to freshwater biodiversity decline and extinction risk.« less
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Habitats of North American sea ducks.
Derksen, Dirk V.; Petersen, Margaret R.; Savard, Jean-Pierre L.
2015-01-01
Breeding, molting, fall and spring staging, and wintering habitats of the sea duck tribe Mergini are described based on geographic locations and distribution in North America, geomorphology, vegetation and soil types, and fresh water and marine characteristics. The dynamics of habitats are discussed in light of natural and anthropogenic events that shape areas important to sea ducks. Strategies for sea duck habitat management are outlined and recommendations for international collaboration to preserve key terrestrial and aquatic habitats are advanced. We follow the definition of habitat advanced by Odum (1971), which is the place or space where an organism lives. Weller (1999) emphasized that habitats for waterbirds required presence of sufficient resources (i.e., food, water, cover, space) for maintenance during a portion of their annual cycle. Habitats exploited by North American sea ducks are diverse, widespread across the continent and adjacent marine waters and until recently, most were only superficially known. A 15-year-long effort funded research on sea duck habitats through the Sea Duck Joint Venture and the Endangered or Threatened Species programs of the United States and Canada. Nevertheless, important gaps remain in our understanding of key elements required by some species during various life stages. Many significant habitats, especially staging and wintering sites, have been and continue to be destroyed or altered by anthropogenic activities. The goal of this chapter is to develop a comprehensive summary of marine, freshwater, and terrestrial habitats and their characteristics by considering sea duck species with similar needs as groups within the tribe Mergini. Additionally, we examine threats and changes to sea duck habitats from human-caused and natural events. Last, we evaluate conservation and management programs underway or available for maintenance and enhancement of habitats critical for sea ducks.
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Determination of Section 404 Permit and Habitat Mitigation Requirements
DOT National Transportation Integrated Search
2012-09-01
The Arizona Department of Transportation (ADOT) is committed to developing habitat, mitigation, : monitoring, and maintenance plans that replace the loss of the functions and values of an area and : are self-sustaining, thereby providing long-term co...
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Bay scallops (Argopecten irradians) inhabit shallow subtidal habitats along the Atlantic coast of the United States and require settlement substrates, such as submerged aquatic vegetation (SAV), for their early juvenile stages. The short lifespan of bay scallops (1-2 yr) coupled...
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Food technology in space habitats
NASA Technical Reports Server (NTRS)
Karel, M.
1979-01-01
The research required to develop a system that will provide for acceptable, nutritious, and safe diets for man during extended space missions is discussed. The development of a food technology system for space habitats capable of converting raw materials produced in the space habitats into acceptable food is examined.
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Chinook salmon use of spawning patches: relative roles of habitat quality, size, and connectivity.
Isaak, Daniel J; Thurow, Russell F; Rieman, Bruce E; Dunham, Jason B
2007-03-01
Declines in many native fish populations have led to reassessments of management goals and shifted priorities from consumptive uses to species preservation. As management has shifted, relevant environmental characteristics have evolved from traditional metrics that described local habitat quality to characterizations of habitat size and connectivity. Despite the implications this shift has for how habitats may be prioritized for conservation, it has been rare to assess the relative importance of these habitat components. We used an information-theoretic approach to select the best models from sets of logistic regressions that linked habitat quality, size, and connectivity to the occurrence of chinook salmon (Oncorhynchus tshawytscha) nests. Spawning distributions were censused annually from 1995 to 2004, and data were complemented with field measurements that described habitat quality in 43 suitable spawning patches across a stream network that drained 1150 km2 in central Idaho. Results indicated that the most plausible models were dominated by measures of habitat size and connectivity, whereas habitat quality was of minor importance. Connectivity was the strongest predictor of nest occurrence, but connectivity interacted with habitat size, which became relatively more important when populations were reduced. Comparison of observed nest distributions to null model predictions confirmed that the habitat size association was driven by a biological mechanism when populations were small, but this association may have been an area-related sampling artifact at higher abundances. The implications for habitat management are that the size and connectivity of existing habitat networks should be maintained whenever possible. In situations where habitat restoration is occurring, expansion of existing areas or creation of new habitats in key areas that increase connectivity may be beneficial. Information about habitat size and connectivity also could be used to strategically
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Habitat use by fishes in coral reefs, seagrass beds and mangrove habitats in the Philippines.
Honda, Kentaro; Nakamura, Yohei; Nakaoka, Masahiro; Uy, Wilfredo H; Fortes, Miguel D
2013-01-01
Understanding the interconnectivity of organisms among different habitats is a key requirement for generating effective management plans in coastal ecosystems, particularly when determining component habitat structures in marine protected areas. To elucidate the patterns of habitat use by fishes among coral, seagrass, and mangrove habitats, and between natural and transplanted mangroves, visual censuses were conducted semiannually at two sites in the Philippines during September and March 2010-2012. In total, 265 species and 15,930 individuals were recorded. Species richness and abundance of fishes were significantly higher in coral reefs (234 species, 12,306 individuals) than in seagrass (38 species, 1,198 individuals) and mangrove (47 species, 2,426 individuals) habitats. Similarity tests revealed a highly significant difference among the three habitats. Fishes exhibited two different strategies for habitat use, inhabiting either a single (85.6% of recorded species) or several habitats (14.4%). Some fish that utilized multiple habitats, such as Lutjanus monostigma and Parupeneus barberinus, showed possible ontogenetic habitat shifts from mangroves and/or seagrass habitats to coral reefs. Moreover, over 20% of commercial fish species used multiple habitats, highlighting the importance of including different habitat types within marine protected areas to achieve efficient and effective resource management. Neither species richness nor abundance of fishes significantly differed between natural and transplanted mangroves. In addition, 14 fish species were recorded in a 20-year-old transplanted mangrove area, and over 90% of these species used multiple habitats, further demonstrating the key role of transplanted mangroves as a reef fish habitat in this region.
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Habitat Use by Fishes in Coral Reefs, Seagrass Beds and Mangrove Habitats in the Philippines
Honda, Kentaro; Nakamura, Yohei; Nakaoka, Masahiro; Uy, Wilfredo H.; Fortes, Miguel D.
2013-01-01
Understanding the interconnectivity of organisms among different habitats is a key requirement for generating effective management plans in coastal ecosystems, particularly when determining component habitat structures in marine protected areas. To elucidate the patterns of habitat use by fishes among coral, seagrass, and mangrove habitats, and between natural and transplanted mangroves, visual censuses were conducted semiannually at two sites in the Philippines during September and March 2010–2012. In total, 265 species and 15,930 individuals were recorded. Species richness and abundance of fishes were significantly higher in coral reefs (234 species, 12,306 individuals) than in seagrass (38 species, 1,198 individuals) and mangrove (47 species, 2,426 individuals) habitats. Similarity tests revealed a highly significant difference among the three habitats. Fishes exhibited two different strategies for habitat use, inhabiting either a single (85.6% of recorded species) or several habitats (14.4%). Some fish that utilized multiple habitats, such as Lutjanus monostigma and Parupeneus barberinus, showed possible ontogenetic habitat shifts from mangroves and/or seagrass habitats to coral reefs. Moreover, over 20% of commercial fish species used multiple habitats, highlighting the importance of including different habitat types within marine protected areas to achieve efficient and effective resource management. Neither species richness nor abundance of fishes significantly differed between natural and transplanted mangroves. In addition, 14 fish species were recorded in a 20-year-old transplanted mangrove area, and over 90% of these species used multiple habitats, further demonstrating the key role of transplanted mangroves as a reef fish habitat in this region. PMID:23976940
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Questad, Erin J; Kellner, James R; Kinney, Kealoha; Cordell, Susan; Asner, Gregory P; Thaxton, Jarrod; Diep, Jennifer; Uowolo, Amanda; Brooks, Sam; Inman-Narahari, Nikhil; Evans, Steven A; Tucker, Brian
2014-03-01
The conservation of species at risk of extinction requires data to support decisions at landscape to regional scales. There is a need for information that can assist with locating suitable habitats in fragmented and degraded landscapes to aid the reintroduction of at-risk plant species. In addition, desiccation and water stress can be significant barriers to the success of at-risk plant reintroduction programs. We examine how airborne light detection and ranging (LiDAR) data can be used to model microtopographic features that reduce water stress and increase resource availability, providing information for landscape planning that can increase the success of reintroduction efforts for a dryland landscape in Hawaii. We developed a topographic habitat-suitability model (HSM) from LiDAR data that identifies topographic depressions that are protected from prevailing winds (high-suitability sites) and contrasts them with ridges and other exposed areas (low-suitability sites). We tested in the field whether high-suitability sites had microclimatic conditions that indicated better-quality habitat compared to low-suitability sites, whether plant-response traits indicated better growing conditions in high-suitability sites, whether the locations of individuals of existing at-risk plant species corresponded with our habitat-suitability classes, and whether the survival of planted individuals of a common native species was greater in high-suitability, compared to low-suitability, planting sites. Mean wind speed in a high-suitability field site was over five times lower than in a low-suitability site, and soil moisture and leaf wetness were greater, indicating less stress and greater resource availability in high-suitability areas. Plant height and leaf nutrient content were greater in high-suitability areas. Six at-risk species showed associations with high-suitability areas. The survival of planted individuals was less variable among high-suitability plots. These results
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A technical guide for monitoring wildlife habitat
M.M. Rowland; C.D. Vojta
2013-01-01
Information about status and trend of wildlife habitat is important for the U.S. Department of Agriculture, Forest Service to accomplish its mission and meet its legal requirements. As the steward of 193 million acres (ac) of Federal land, the Forest Service needs to evaluate the status of wildlife habitat and how it compares with desired conditions. Habitat monitoring...
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Zhang, Danli; Ye, Zhen; Yamada, Kazutaka; Zhen, Yahui; Zheng, Chenguang; Bu, Wenjun
2016-08-31
On account of repeated exposure and submergence of the East China Sea (ECS) land bridge, sea level fluctuation played an important role in shaping the population structure of many temperate species across the ECS during the glacial period. The flower bug Amphiareus obscuriceps (Poppius, 1909) (Hemiptera: Anthocoridae) is an invasive species native to the Sino-Japanese Region (SJR) of East Asia. We tested the hypothesis of the ECS land bridge acting as a dispersal corridor or filter for A. obscuriceps during the glacial period. Specifically, we tested whether and the extent to which dispersal ability and host plant habitat requirement influenced the genetic structure of A. obscuriceps during the exposure of the ECS land bridge. Phylogenetic and network analyses indicated that A. obscuriceps is composed of two major lineages, i.e., China and Japan. Divergence time on both sides of the ECS was estimated to be approximately 1.07 (0.79-1.32) Ma, which was about the same period that the sea level increased. No significant Isolation by Distance (IBD) relationship was found between Фst and Euclidean distances in the Mantel tests, which is consistent with the hypothesis that this species has a good dispersal ability. Our Last Glacial Maximum (LGM) niche modeling of plants that constitute preferred habitats for A. obscuriceps exhibited a similar habitat gap on the exposed ECS continental shelf between China and Japan, but showed a continuous distribution across the Taiwan Strait. Our results suggest that ecological properties (habitat requirement and dispersal ability), together with sea level fluctuation during the Pleistocene across the ECS, have shaped the genetic structure and demographic history of A. obscuriceps in its native area. The host plant habitat requirement could also be a key to the colonization of the A. obscuriceps species during the exposure of the ECS land bridge. Our findings will shed light on the potential role of habitat requirement in the process of
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IMPLICATIONS OF INTER-HABITAT VARIATION FOR MONITORING GREAT RIVER ECOSYSTEMS: EMAP-UMR EXPERIENCE
Great River ecosystems (GREs) are complex mosaics of habitats that vary at multiple scales. GRE monitoring designs can capture some but not all of this variation. Each discrete habitat, however defined, must either be sampled as a separate strata or "resource population", combine...
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Knick, Steven T; Hanser, Steven E; Preston, Kristine L
2013-06-01
Greater sage-grouse Centrocercus urophasianus (Bonaparte) currently occupy approximately half of their historical distribution across western North America. Sage-grouse are a candidate for endangered species listing due to habitat and population fragmentation coupled with inadequate regulation to control development in critical areas. Conservation planning would benefit from accurate maps delineating required habitats and movement corridors. However, developing a species distribution model that incorporates the diversity of habitats used by sage-grouse across their widespread distribution has statistical and logistical challenges. We first identified the ecological minimums limiting sage-grouse, mapped similarity to the multivariate set of minimums, and delineated connectivity across a 920,000 km(2) region. We partitioned a Mahalanobis D (2) model of habitat use into k separate additive components each representing independent combinations of species-habitat relationships to identify the ecological minimums required by sage-grouse. We constructed the model from abiotic, land cover, and anthropogenic variables measured at leks (breeding) and surrounding areas within 5 km. We evaluated model partitions using a random subset of leks and historic locations and selected D (2) (k = 10) for mapping a habitat similarity index (HSI). Finally, we delineated connectivity by converting the mapped HSI to a resistance surface. Sage-grouse required sagebrush-dominated landscapes containing minimal levels of human land use. Sage-grouse used relatively arid regions characterized by shallow slopes, even terrain, and low amounts of forest, grassland, and agriculture in the surrounding landscape. Most populations were interconnected although several outlying populations were isolated because of distance or lack of habitat corridors for exchange. Land management agencies currently are revising land-use plans and designating critical habitat to conserve sage-grouse and avoid endangered
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Knick, Steven T.; Hanser, Steven E.; Preston, Kristine L.
2013-01-01
Greater sage-grouse Centrocercus urophasianus (Bonaparte) currently occupy approximately half of their historical distribution across western North America. Sage-grouse are a candidate for endangered species listing due to habitat and population fragmentation coupled with inadequate regulation to control development in critical areas. Conservation planning would benefit from accurate maps delineating required habitats and movement corridors. However, developing a species distribution model that incorporates the diversity of habitats used by sage-grouse across their widespread distribution has statistical and logistical challenges. We first identified the ecological minimums limiting sage-grouse, mapped similarity to the multivariate set of minimums, and delineated connectivity across a 920,000 km2 region. We partitioned a Mahalanobis D2 model of habitat use into k separate additive components each representing independent combinations of species–habitat relationships to identify the ecological minimums required by sage-grouse. We constructed the model from abiotic, land cover, and anthropogenic variables measured at leks (breeding) and surrounding areas within 5 km. We evaluated model partitions using a random subset of leks and historic locations and selected D2 (k = 10) for mapping a habitat similarity index (HSI). Finally, we delineated connectivity by converting the mapped HSI to a resistance surface. Sage-grouse required sagebrush-dominated landscapes containing minimal levels of human land use. Sage-grouse used relatively arid regions characterized by shallow slopes, even terrain, and low amounts of forest, grassland, and agriculture in the surrounding landscape. Most populations were interconnected although several outlying populations were isolated because of distance or lack of habitat corridors for exchange. Land management agencies currently are revising land-use plans and designating critical habitat to conserve sage-grouse and avoid endangered
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Erwin, R.M.; Allen, D.H.; Jenkins, D.
2003-01-01
Nesting colonial waterbirds along the Atlantic Coast of the United States face a number of landscape-level threats including human disturbance, mammalian predator expansion, and habitat alteration. There have been changes from 1977 to the mid-1990s in use of nesting habitats and populations of a number of seabird species of concern in the region, including black skimmers Rynchops niger Linnaeaus, common terns Sterna hirundo Linnaeaus, gull-billed terns Sterna nilotica Linnaeaus, least terns Sterna antillarum Lesson, royal terns Sterna maxima Boddaert, and sandwich terns Sterna sandvicensis Cabot. These species form colonies primarily on the following habitat types: large, sandy barrier or shoal islands, natural estuarine or bay islands (mostly marsh), man-made islands of dredged deposition materials (from navigation channels), and the mainland. Significant changes in the use of the dredged material islands have occurred for these species in New Jersey and North Carolina, but not in Virginia. Population declines and changes in bird habitat use appear to be at least partially associated with the conditions and management of the existing dredged material islands, coastal policy changes associated with creating new dredged material islands, and competing demands for sand for beach augmentation by coastal communities. As these and other coastal habitats become less suitable for colonial waterbirds, other manmade sites, such as bridges and buildings have become increasingly more important. In regions with intense recreational demands, coastal wildlife managers need to take a more aggressive role in managing natural and man-made habitats areas and as stakeholders in the decision-making process involving dredged materials and beach sand allocation.
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Implications of different shorebird migration strategies for habitat conservation
Susan K. Skagen; Stephen Brown; Rex Johnson
2005-01-01
Shorebird migration strategies vary by species, migration distance and route, time of year, and resources at staging and stopover sites. The Western Hemisphere Shorebird Reserve Network has been highly successful in the identification, designation, and protection of important migration habitats for many species that stage in traditional areas. Recently, conservation...
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Wirth, Lisa; Rosenberger, Amanda; Prakash, Anupma; Gens, Rudiger; Margraf, F. Joseph; Hamazaki, Toshihide
2012-01-01
At northern limits of a species’ distribution, fish habitat requirements are often linked to thermal preferences, and the presence of overwintering habitat. However, logistical challenges and hydrologic processes typical of glacial systems could compromize the identification of these habitats, particularly in large river environments. Our goal was to identify and characterize spawning habitat for fall-run chum salmon Oncorhynchus keta and model habitat selection from spatial distributions of tagged individuals in the Tanana River, Alaska using an approach that combined ground surveys with remote sensing. Models included braiding, sinuosity, ice-free water surface area (indicating groundwater influence), and persistent ice-free water (i.e., consistent presence of ice-free water for a 12-year period according to satellite imagery). Candidate models containing persistent ice-free water were selected as most likely, highlighting the utility of remote sensing for monitoring and identifying salmon habitat in remote areas. A combination of ground and remote surveys revealed spatial and temporal thermal characteristics of these habitats that could have strong biological implications. Persistent ice-free sites identified using synthetic aperture radar appear to serve as core areas for spawning fall chum salmon, and the importance of stability through time suggests a legacy of successful reproductive effort for this homing species. These features would not be captured with a one-visit traditional survey but rather required remote-sensing monitoring of the sites through time.
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Yandow, Leah H; Chalfoun, Anna D; Doak, Daniel F
2015-01-01
Some of the most compelling examples of ecological responses to climate change are elevational range shifts of individual species, which have been observed throughout the world. A growing body of evidence, however, suggests substantial mediation of simple range shifts due to climate change by other limiting factors. Understanding limiting factors for a species within different contexts, therefore, is critical for predicting responses to climate change. The American pika (Ochotona princeps) is an ideal species for investigating distributions in relation to climate because of their unusual and well-understood natural history as well as observed shifts to higher elevation in parts of their range. We tested three hypotheses for the climatic or habitat characteristics that may limit pika presence and abundance: summer heat, winter snowpack, and forage availability. We performed these tests using an index of pika abundance gathered in a region where environmental influences on pika distribution have not been well-characterized. We estimated relative pika abundance via scat surveys and quantified climatic and habitat characteristics across two North-Central Rocky Mountain Ranges, the Wind River and Bighorn ranges in Wyoming, USA. Pika scat density was highest at mid-elevations and increased linearly with forage availability in both ranges. Scat density also increased with temperatures conducive to forage plant growth, and showed a unimodal relationship with the number of days below -5°C, which is modulated by insulating snowpack. Our results provide support for both the forage availability and winter snowpack hypotheses. Especially in montane systems, considering the context-dependent nature of climate effects across regions and elevations as well as interactions between climatic and other critical habitat characteristics, will be essential for predicting future species distributions.
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Chinook salmon use of spawning patches: Relative roles of habitat quality, size, and connectivity
Isaak, D.J.; Thurow, R.F.; Rieman, B.E.; Dunham, J.B.
2007-01-01
Declines in many native fish populations have led to reassessments of management goals and shifted priorities from consumptive uses to species preservation. As management has shifted, relevant environmental characteristics have evolved from traditional metrics that described local habitat quality to characterizations of habitat size and connectivity. Despite the implications this shift has for how habitats may be prioritized for conservation, it has been rare to assess the relative importance of these habitat components. We used an information-theoretic approach to select the best models from sets of logistic regressions that linked habitat quality, size, and connectivity to the occurrence of chinook salmon (Oncorhynchus tshawytscha) nests. Spawning distributions were censused annually from 1995 to 2004, and data were complemented with field measurements that described habitat quality in 43 suitable spawning patches across a stream network that drained 1150 km 2 in central Idaho. Results indicated that the most plausible models were dominated by measures of habitat size and connectivity, whereas habitat quality was of minor importance. Connectivity was the strongest predictor of nest occurrence, but connectivity interacted with habitat size, which became relatively more important when populations were reduced. Comparison of observed nest distributions to null model predictions confirmed that the habitat size association was driven by a biological mechanism when populations were small, but this association may have been an area-related sampling artifact at higher abundances. The implications for habitat management are that the size and connectivity of existing habitat networks should be maintained whenever possible. In situations where habitat restoration is occurring, expansion of existing areas or creation of new habitats in key areas that increase connectivity may be beneficial. Information about habitat size and connectivity also could be used to strategically
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NASA Astrophysics Data System (ADS)
Davies, J. S.; Guillaumont, B.; Tempera, F.; Vertino, A.; Beuck, L.; Ólafsdóttir, S. H.; Smith, C. J.; Fosså, J. H.; van den Beld, I. M. J.; Savini, A.; Rengstorf, A.; Bayle, C.; Bourillet, J.-F.; Arnaud-Haond, S.; Grehan, A.
2017-11-01
Cold-water corals (CWC) can form complex structures which provide refuge, nursery grounds and physical support for a diversity of other living organisms. However, irrespectively from such ecological significance, CWCs are still vulnerable to human pressures such as fishing, pollution, ocean acidification and global warming Providing coherent and representative conservation of vulnerable marine ecosystems including CWCs is one of the aims of the Marine Protected Areas networks being implemented across European seas and oceans under the EC Habitats Directive, the Marine Strategy Framework Directive and the OSPAR Convention. In order to adequately represent ecosystem diversity, these initiatives require a standardised habitat classification that organises the variety of biological assemblages and provides consistent and functional criteria to map them across European Seas. One such classification system, EUNIS, enables a broad level classification of the deep sea based on abiotic and geomorphological features. More detailed lower biotope-related levels are currently under-developed, particularly with regards to deep-water habitats (>200 m depth). This paper proposes a hierarchical CWC biotope classification scheme that could be incorporated by existing classification schemes such as EUNIS. The scheme was developed within the EU FP7 project CoralFISH to capture the variability of CWC habitats identified using a wealth of seafloor imagery datasets from across the Northeast Atlantic and Mediterranean. Depending on the resolution of the imagery being interpreted, this hierarchical scheme allows data to be recorded from broad CWC biotope categories down to detailed taxonomy-based levels, thereby providing a flexible yet valuable information level for management. The CWC biotope classification scheme identifies 81 biotopes and highlights the limitations of the classification framework and guidance provided by EUNIS, the EC Habitats Directive, OSPAR and FAO; which largely
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Selecting habitat management strategies on refuges
Schroeder, Richard L.; King, Wayne J.; Cornely, John E.
1998-01-01
This report is a joint effort of the Biological Resources Division, U.S. Geological Survey and the U.S. Fish and Wildlife Service (FWS) to provide National Wildlife Refuge (NWR) managers guidance on the selection and evaluation of habitat management strategies to meet stated objectives. The FWS recently completed a handbook on writing refuge management goals and objectives (U.S. Fish and Wildlife Service 1996a). the National Wildlife Refuge System Improvement Act of 1997 requires that National Wildlife Refuge System (NWRS) lands be managed according to approved Comprehensive Conservation Plans to guide management decisions and devise strategies for achieving refuge unit purposes and meeting the NWRS mission. It is expected that over the next several years most refuges will develop new or revised refuge goals and objectives for directing their habitat management strategies. This paper outlines the steps we recommend in selecting and evaluating habitat management strategies to meet specific refuge habitat objectives. We selected two examples to illustrate the process. Although each refuge is unique and will require specific information and solutions, these two examples can be used as guidance when selecting and evaluating habitat management strategies for other refuge resources: Example 1. Management of floodplain woods habitat for forest interior birds. The biological recourse of concern is the quality and quantity of floodplain woods habitat for eastern forest interior birds in the Cypress Creek NWR (U.S. Fish and Wildlife Service 1996b). Example 2. Management of habitat for biodiversity: Historical landscape proportions. The biological resource of concern is the change in diversity associated with man-induced changes in the distribution and abundance of habitat types at the Minnesota Valley NWR (U.S. Fish and Wildlife Service 1996c).
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Bjørneraas, Kari; Herfindal, Ivar; Solberg, Erling Johan; Sæther, Bernt-Erik; van Moorter, Bram; Rolandsen, Christer Moe
2012-01-01
Identifying factors shaping variation in resource selection is central for our understanding of the behaviour and distribution of animals. We examined summer habitat selection and space use by 108 Global Positioning System (GPS)-collared moose in Norway in relation to sex, reproductive status, habitat quality, and availability. Moose selected habitat types based on a combination of forage quality and availability of suitable habitat types. Selection of protective cover was strongest for reproducing females, likely reflecting the need to protect young. Males showed strong selection for habitat types with high quality forage, possibly due to higher energy requirements. Selection for preferred habitat types providing food and cover was a positive function of their availability within home ranges (i.e. not proportional use) indicating functional response in habitat selection. This relationship was not found for unproductive habitat types. Moreover, home ranges with high cover of unproductive habitat types were larger, and smaller home ranges contained higher proportions of the most preferred habitat type. The distribution of moose within the study area was partly related to the distribution of different habitat types. Our study shows how distribution and availability of habitat types providing cover and high-quality food shape ungulate habitat selection and space use.
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Bennett, Victoria A.; Doerr, Veronica A. J.; Doerr, Erik D.; Manning, Adrian D.; Lindenmayer, David B.; Yoon, Hwan-Jin
2012-01-01
It is essential to choose suitable habitat when reintroducing a species into its former range. Habitat quality may influence an individual’s dispersal decisions and also ultimately where they choose to settle. We examined whether variation in habitat quality (quantified by the level of ground vegetation cover and the installation of nest boxes) influenced the movement, habitat choice and survival of a reintroduced bird species. We experimentally reintroduced seven social groups (43 individuals) of the brown treecreeper (Climacteris picumnus) into two nature reserves in south-eastern Australia. We radio-tracked 18 brown treecreepers from release in November 2009 until February 2010. We observed extensive movements by individuals irrespective of the release environment or an individual’s gender. This indicated that individuals were capable of dispersing and actively selecting optimum habitat. This may alleviate pressure on wildlife planners to accurately select the most optimum release sites, so long as the species’ requirements are met. There was significant variation in movement between social groups, suggesting that social factors may be a more important influence on movement than habitat characteristics. We found a significant effect of ground vegetation cover on the likelihood of settlement by social groups, with high rates of settlement and survival in dry forests, rather than woodland (where the species typically resides), which has implications for the success of woodland restoration. However, overall the effects of variation in habitat quality were not as strong as we had expected, and resulted in some unpredicted effects such as low survival and settlement in woodland areas with medium levels of ground vegetation cover. The extensive movement by individuals and unforeseen effects of habitat characteristics make it difficult to predict the outcome of reintroductions, the movement behaviour and habitat selection of reintroduced individuals, particularly
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Pitheciids in fragmented habitats: Land cover change and its implications for conservation.
Boyle, Sarah A
2016-05-01
Pitheciids (Cacajao, Callicebus, Chiropotes, and Pithecia) have experienced habitat loss and fragmentation across their geographic range in South America. Some populations living in habitat fragments live in smaller groups, travel shorter distances, and consume items that are not regularly found in the diets of populations living in continuous habitat; however, these patterns are not consistent across species. I used the IUCN Red List of Threatened Species to delineate the geographic range and conservation status of 43 pitheciid species. I calculated the amount of modified land cover within the range of each species, as well as the extent to which the remaining habitat exists in small fragments and the amount of forest lost from 2000 to 2012. Mean forest fragment size ranged from 12 to 12,027 ha, and mean forest loss from 2000 to 2012 ranged from 10.7% for Chiropotes to 0.9% for Pithecia. Critically Endangered and Endangered species represented 20.9% of the pitheciid species, and 46.5% of these species had population trends documented as decreasing. Total modified land cover was greatest for Callicebus species (18.0% of geographic range), followed by Chiropotes (13.8%), Pithecia (4.4%), and Cacajao (1.1%). Species of greater conservation concern had smaller geographic ranges, and a greater percentage of their range consisting of modified land cover than species of lower conservation concern. Species of greater conservation concern also had a greater percentage of forest lost from 2000 to 2012 and a smaller percentage of the remaining forest being protected. Most studies of pitheciids in fragments have concentrated on census data; the behavior of pitheciids in fragments has been examined for only 9 of the 43 species. Increased data on the responses of pitheciid species to forest loss and fragmentation are necessary in order to address pitheciid conservation, especially in areas undergoing severe habitat loss. © 2014 Wiley Periodicals, Inc.
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Yandow, Leah H.; Chalfoun, Anna D.; Doak, Daniel F.
2015-01-01
Some of the most compelling examples of ecological responses to climate change are elevational range shifts of individual species, which have been observed throughout the world. A growing body of evidence, however, suggests substantial mediation of simple range shifts due to climate change by other limiting factors. Understanding limiting factors for a species within different contexts, therefore, is critical for predicting responses to climate change. The American pika (Ochotona princeps) is an ideal species for investigating distributions in relation to climate because of their unusual and well-understood natural history as well as observed shifts to higher elevation in parts of their range. We tested three hypotheses for the climatic or habitat characteristics that may limit pika presence and abundance: summer heat, winter snowpack, and forage availability. We performed these tests using an index of pika abundance gathered in a region where environmental influences on pika distribution have not been well-characterized. We estimated relative pika abundance via scat surveys and quantified climatic and habitat characteristics across two North-Central Rocky Mountain Ranges, the Wind River and Bighorn ranges in Wyoming, USA. Pika scat density was highest at mid-elevations and increased linearly with forage availability in both ranges. Scat density also increased with temperatures conducive to forage plant growth, and showed a unimodal relationship with the number of days below -5°C, which is modulated by insulating snowpack. Our results provide support for both the forage availability and winter snowpack hypotheses. Especially in montane systems, considering the context-dependent nature of climate effects across regions and elevations as well as interactions between climatic and other critical habitat characteristics, will be essential for predicting future species distributions. PMID:26244851
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Yandow, Leah H.; Chalfoun, Anna D.; Doak, Daniel F.
2015-01-01
Some of the most compelling examples of ecological responses to climate change are elevational range shifts of individual species, which have been observed throughout the world. A growing body of evidence, however, suggests substantial mediation of simple range shifts due to climate change by other limiting factors. Understanding limiting factors for a species within different contexts, therefore, is critical for predicting responses to climate change. The American pika (Ochotona princeps) is an ideal species for investigating distributions in relation to climate because of their unusual and well-understood natural history as well as observed shifts to higher elevation in parts of their range. We tested three hypotheses for the climatic or habitat characteristics that may limit pika presence and abundance: summer heat, winter snowpack, and forage availability. We performed these tests using an index of pika abundance gathered in a region where environmental influences on pika distribution have not been well-characterized. We estimated relative pika abundance via scat surveys and quantified climatic and habitat characteristics across two North-Central Rocky Mountain Ranges, the Wind River and Bighorn ranges in Wyoming, USA. Pika scat density was highest at mid-elevations and increased linearly with forage availability in both ranges. Scat density also increased with temperatures conducive to forage plant growth, and showed a unimodal relationship with the number of days below -5°C, which is modulated by insulating snowpack. Our results provide support for both the forage availability and winter snowpack hypotheses. Especially in montane systems, considering the context-dependent nature of climate effects across regions and elevations as well as interactions between climatic and other critical habitat characteristics, will be essential for predicting future species distributions.
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Habitat Distribution of Birds Wintering in Central Andros, The Bahamas: Implications for Management
DAVE CURRIE; JOSEPH M. WUNDERLE JR.; DAVID N. EWERT; MATTHEW R. ANDERSON; ANCILLENO DAVIS; JASMINE TURNER
2005-01-01
We studied winter avian distribution in three representative pine-dominated habitats and three broadleaf habitats in an area recently designated as a National Park on Andros Island, The Bahamas, 1-23 February 2002. During 180 five-minute point counts, 1731 individuals were detected (1427 permanent residents and 304 winter residents) representing 51 species (29...
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Michelle A. Labbe; David I. King; Tim A. Mousseau
2014-01-01
Many species of mature forest-nesting birds ("forest birds") undergo a pronounced shift in habitat use during the post-fledging period and move from their forest nesting sites into areas of early-successional vegetation. Mortality is high during this period, thus understanding the resource requirements of post-fledging birds has implications for conservation...
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Confounding factors in the detection of species responses to habitat fragmentation.
Ewers, Robert M; Didham, Raphael K
2006-02-01
Habitat loss has pervasive and disruptive impacts on biodiversity in habitat remnants. The magnitude of the ecological impacts of habitat loss can be exacerbated by the spatial arrangement -- or fragmentation -- of remaining habitat. Fragmentation per se is a landscape-level phenomenon in which species that survive in habitat remnants are confronted with a modified environment of reduced area, increased isolation and novel ecological boundaries. The implications of this for individual organisms are many and varied, because species with differing life history strategies are differentially affected by habitat fragmentation. Here, we review the extensive literature on species responses to habitat fragmentation, and detail the numerous ways in which confounding factors have either masked the detection, or prevented the manifestation, of predicted fragmentation effects. Large numbers of empirical studies continue to document changes in species richness with decreasing habitat area, with positive, negative and no relationships regularly reported. The debate surrounding such widely contrasting results is beginning to be resolved by findings that the expected positive species-area relationship can be masked by matrix-derived spatial subsidies of resources to fragment-dwelling species and by the invasion of matrix-dwelling species into habitat edges. Significant advances have been made recently in our understanding of how species interactions are altered at habitat edges as a result of these changes. Interestingly, changes in biotic and abiotic parameters at edges also make ecological processes more variable than in habitat interiors. Individuals are more likely to encounter habitat edges in fragments with convoluted shapes, leading to increased turnover and variability in population size than in fragments that are compact in shape. Habitat isolation in both space and time disrupts species distribution patterns, with consequent effects on metapopulation dynamics and the
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Habitat Specialization in Tropical Continental Shelf Demersal Fish Assemblages
Fitzpatrick, Ben M.; Harvey, Euan S.; Heyward, Andrew J.; Twiggs, Emily J.; Colquhoun, Jamie
2012-01-01
The implications of shallow water impacts such as fishing and climate change on fish assemblages are generally considered in isolation from the distribution and abundance of these fish assemblages in adjacent deeper waters. We investigate the abundance and length of demersal fish assemblages across a section of tropical continental shelf at Ningaloo Reef, Western Australia, to identify fish and fish habitat relationships across steep gradients in depth and in different benthic habitat types. The assemblage composition of demersal fish were assessed from baited remote underwater stereo-video samples (n = 304) collected from 16 depth and habitat combinations. Samples were collected across a depth range poorly represented in the literature from the fringing reef lagoon (1–10 m depth), down the fore reef slope to the reef base (10–30 m depth) then across the adjacent continental shelf (30–110 m depth). Multivariate analyses showed that there were distinctive fish assemblages and different sized fish were associated with each habitat/depth category. Species richness, MaxN and diversity declined with depth, while average length and trophic level increased. The assemblage structure, diversity, size and trophic structure of demersal fishes changes from shallow inshore habitats to deeper water habitats. More habitat specialists (unique species per habitat/depth category) were associated with the reef slope and reef base than other habitats, but offshore sponge-dominated habitats and inshore coral-dominated reef also supported unique species. This suggests that marine protected areas in shallow coral-dominated reef habitats may not adequately protect those species whose depth distribution extends beyond shallow habitats, or other significant elements of demersal fish biodiversity. The ontogenetic habitat partitioning which is characteristic of many species, suggests that to maintain entire species life histories it is necessary to protect corridors of connected
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SHERMAN L. BURSON III; LEONARD R. REITSMA; PAMELA D. HUNT
2005-01-01
Abstract.âUsing evidence from individually-marked birds and radio-telemetry, we studied daily and seasonal habitat use of Northern Waterthrushes (Seiurus novaboracensis) in Puerto Rico during the nonbreeding season from 1999 to 2001. Our study was conducted in mangrove habitats along the southwest and east coasts and near ponds and washes in mesquite savanna in the...
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NASA Astrophysics Data System (ADS)
Timm, R. K.; Wissmar, R. C.; Berge, H.; Foley, S.
2005-05-01
Anthropogenic controls on rivers such as dams, hardened banks, and land uses limit the interactions between main river channel and floodplain ecosystems and contribute to decreased habitat diversity. These system controls dampen the frequency and magnitude of natural disturbances that contibute to physical habitat structure and variability. Under natural and altered disturbance regimes river systems are expected to exhibit resiliency. However, in some cases, disturbances cause fluctuations in the trajectory of the mean system state that can have implications for river recovery in the short- and long-term by changing the spatial and temporal dimensions of available habitat relative to specific biological requirements. Historic and contemporary salmon spawning data are analyzed in the context of changing disturbance regimes in the Cedar River, Washington. Historic data are presented for active channel conditions and spawning fish distributions. Contemporary data are presented for an intensively studied reach that received a landslide that deposited approximately 50,000 m3 of sediment in the main channel, temporarily damming the river. Biologically, the spatio-temporal spawning distributions of Chinook (Oncorhynchus tshawytcha) and sockeye (O. nerka) salmon responded to modifications of physical habitat.
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Deep Space Habitat Concept Demonstrator
NASA Technical Reports Server (NTRS)
Bookout, Paul S.; Smitherman, David
2015-01-01
This project will develop, integrate, test, and evaluate Habitation Systems that will be utilized as technology testbeds and will advance NASA's understanding of alternative deep space mission architectures, requirements, and operations concepts. Rapid prototyping and existing hardware will be utilized to develop full-scale habitat demonstrators. FY 2014 focused on the development of a large volume Space Launch System (SLS) class habitat (Skylab Gen 2) based on the SLS hydrogen tank components. Similar to the original Skylab, a tank section of the SLS rocket can be outfitted with a deep space habitat configuration and launched as a payload on an SLS rocket. This concept can be used to support extended stay at the Lunar Distant Retrograde Orbit to support the Asteroid Retrieval Mission and provide a habitat suitable for human missions to Mars.
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Loss and modification of habitat: Chapter 1
Lemckert, Francis; Hecnar, Stephen; Pilliod, David S.
2012-01-01
Amphibians live in a wide variety of habitats around the world, many of which have been modified or destroyed by human activities. Most species have unique life history characteristics adapted to specific climates, habitats (e.g., lentic, lotic, terrestrial, arboreal, fossorial, amphibious), and local conditions that provide suitable areas for reproduction, development and growth, shelter from environmental extremes, and predation, as well as connectivity to other populations or habitats. Although some species are entirely aquatic or terrestrial, most amphibians, as their name implies, lead a dual life and require a mosaic of habitats in both aquatic and terrestrial ecosystems. With over 6 billion people on Earth, most species are now persisting in habitats that have been directly or indirectly influenced by human activities. Some species have disappeared where their habitats have been completely destroyed, reduced, or rendered unsuitable. Habitat loss and degradation are widely considered by most researchers as the most important causes of amphibian population decline globally (Barinaga 1990; Wake and Morowitz 1991; Alford and Richards 1999). In this chapter, a background on the diverse habitat requirements of amphibians is provided, followed by a discussion of the effects of urbanization, agriculture, livestock grazing, timber production and harvesting, fire and hazardous fuel management, and roads on amphibians and their habitats. Also briefly discussed is the influence on amphibian habitats of natural disturbances, such as extreme weather events and climate change, given the potential for human activities to impact climate in the longer term. For amphibians in general, microhabitats are of greater importance than for other vertebrates. As ectotherms with a skin that is permeable to water and with naked gelatinous eggs, amphibians are physiologically constrained to be active during environmental conditions that provide appropriate body temperatures and adequate
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Assessing patterns of fish demographics and habitat in stream networks
Effective habitat restoration planning requires correctly anticipating demographic responses to altered habitats. New applications of Passive Integrated Transponder (PIT) tag technology to fish-habitat research have provided critical insights into fish movement, growth, and surv...
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NASA Astrophysics Data System (ADS)
Jordan, M. S.; Alexander, J. D.; Grant, G. E.; Bartholomew, J. L.
2011-12-01
Management strategies for parasites with complex life cycles may target not the parasite itself, but one of the alternate hosts. One approach is to decrease habitat for the alternate host, and in river systems flow manipulations may be employed. Two-dimensional hydraulic models can be powerful tools for predicting the relationship between flow alterations and changes in physical habit, however they require a rigorous definition of physical habitat for the organism of interest. We present habitat characterization data for the case of the alternate host of a salmonid parasite and introduce how it will be used in conjunction with a 2-dimensional hydraulic model. Ceratomyxa shasta is a myxozoan parasite of salmonids that requires a freshwater polychaete Manayunkia speciosa to complete its life cycle. Manayunkia speciosa is a small (3mm) benthic filter-feeding worm that attaches itself perpendicularly to substrate through construction of a flexible tube. In the Klamath River, CA/OR, C. shasta causes significant juvenile salmon mortality, imposing social and economic losses on commercial, sport and tribal fisheries. An interest in manipulating habitat for the polychaete host to decrease the abundance of C. shasta has therefore developed. Unfortunately, there are limited data on the habitat requirements of M. speciosa or the influence of streamflow regime and hydraulics on population dynamics and infection prevalence. This work aims to address these data needs by identifying physical habitat variables that influence the distribution of M. speciosa and determining the relationship between those variables, M. speciosa population density, and C. shasta infection prevalence. Biological samples were collected from nine sites representing three river features (runs, pools, and eddies) within the Klamath River during the summer and fall of 2010 and 2011. Environmental data including depth, velocity, and substrate, were collected at each polychaete sampling location. We tested
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Effects of habitat loss and fragmentation on amphibians: A review and prospectus
Samuel A. Cushman
2006-01-01
Habitat loss and fragmentation are among the largest threats to amphibian populations. However, most studies have not provided clear insights into their population-level implications. There is a critical need to investigate the mechanisms that underlie patterns of distribution and abundance. In order to understand the population- and species-level implications of...
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Vadell, María Victoria; García Erize, Francisco; Gómez Villafañe, Isabel Elisa
2017-01-01
Hantavirus pulmonary syndrome is a severe cardio pulmonary disease transmitted to humans by sylvan rodents found in natural and rural environments. Disease transmission is closely linked to the ecology of animal reservoirs and abiotic factors such as habitat characteristics, season or climatic conditions. The main goals of this research were: to determine the biotic and abiotic factors affecting richness and abundance of rodent species at different spatial scales, to evaluate different methodologies for studying population of small rodents, and to describe and analyze an ecologically-based rodent management experience in a highly touristic area. A 4-year study of small rodent ecology was conducted between April 2007 and August 2011 in the most relevant habitats of El Palmar National Park, Argentina. Management involved a wide range of control and prevention measures, including poisoning, culling and habitat modification. A total of 172 individuals of 5 species were captured with a trapping effort of 13 860 traps-nights (1.24 individuals/100 traps-nights). Five rodent species were captured, including 2 hantavirus-host species, Oligoryzomys nigripes and Akodon azarae. Oligoryzomys nigripes, host of a hantavirus that is pathogenic in humans, was the most abundant species and the only one found in all the studied habitats. Our results are inconsistent with the dilution effect hypothesis. The present study demonstrates that sylvan rodent species, including the hantavirus-host species, have distinct local habitat selection and temporal variation patterns in abundance, which may influence the risk of human exposure to hantavirus and may have practical implications for disease transmission as well as for reservoir management. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.
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Morrogh-Bernard, Helen C; Husson, Simon J; Harsanto, Fransiskus A; Chivers, David J
2014-01-01
This study was conducted to see how orang-utans (Pongo pygmaeus wurmbii) were coping with fine-scale habitat disturbance in a selectively logged peat swamp forest in Central Kalimantan, Borneo. Seven habitat classes were defined, and orang-utans were found to use all of these, but were selective in their preference for certain classes over others. Overall, the tall forest classes (≥20 m) were preferred. They were preferred for feeding, irrespective of canopy connectivity, whereas classes with a connected canopy (canopy cover ≥75%), irrespective of canopy height, were preferred for resting and nesting, suggesting that tall trees are preferred for feeding and connected canopy for security and protection. The smaller forest classes (≤10 m high) were least preferred and were used mainly for travelling from patch to patch. Thus, selective logging is demonstrated here to be compatible with orang-utan survival as long as large food trees and patches of primary forest remain. Logged forest, therefore, should not automatically be designated as 'degraded'. These findings have important implications for forest management, forest classification and the designation of protected areas for orang-utan conservation.
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Creating Habitat for the Yellow-Billed Cuckoo (Coccyzus americana)
Bertin W. Anderson; Stephen A. Laymon
1989-01-01
Yellow-billed Cuckoo numbers have decreased alarmingly in recent decades. This is associated with demise of their riparian habitats. Study of habitat along the lower Colorado River and along the South Fork Kern River led to the conclusion that they require dense habitats dominated by cottonwood (Populus fremontii) and willow (Salix...
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Jaguar critical habitat designation causes concern for Southwestern ranchers
Svancara, Colleen; Lien, Aaron M.; Vanasco, Wendy T.; Laura Lopez-Hoffman,; Ruyle, George B.
2015-01-01
The designation of jaguar critical habitat in April 2014 in southern Arizona and southwestern New Mexico created concern for livestock ranchers in the region. We interviewed ranchers to understand their concerns with the jaguar critical habitat designation and their attitudes toward jaguars, wildlife conservation, and resource management in general. Ranchers we interviewed were concerned about direct impacts of designated critical habitat on ranching, as well as possible alternative agendas of critical habitat advocates and issues specific to the borderlands region. The ranchers were less concerned about the presence of jaguars but were more concerned about possible limiting effects of the Endangered Species Act (ESA), distrust of government entities, and litigious environmental groups. To maximize effectiveness, government agencies should work to foster trust in the ranching community, be cognizant of sensitive issues specific to the region that may challenge endangered species conservation goals, recognize the opportunity to work with ranchers for endangered species management, and provide outreach about implications of the ESA.
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Tomlinson, Matthew J; Gergel, Sarah E; Beechie, Timothy J; McClure, Michelle M
2011-07-01
Rivers and their associated floodplains are among the world's most highly altered ecosystems, resulting in billions of dollars in restoration expenditures. Successful restoration of these systems requires information at multiple spatial scales (from localized reaches to broader-scale watersheds), as well as information spanning long time frames. Here, we develop a suite of historical landscape indicators of riverine status, primarily from the perspective of salmonid management, using a case study in the Interior Columbia Basin, Washington, USA. We use a combination of historical and modern aerial photography to quantify changes in land cover and reach type, as well as potential fish habitat within channel and off-channel floodplain areas. As of 1949, 55% of the Wenatchee River floodplain had been converted to agriculture. By 2006, 62% had been modified by anthropogenic development, of which 20% was due to urban expansion. The historical percentage of agricultural land in the watershed and the contemporary percentage of urban area surpass thresholds in land cover associated with deleterious impacts on river systems. In addition, the abundance of reach types associated with the highest quality salmonid habitat (island braided and meandering reaches) has declined due to conversion to straight reach types. The area occupied by fish habitats associated with channel migration (slow/stagnant channels and dry channels) has declined approximately 25-30%. Along highly modified rivers, these habitats have also become increasingly fragmented. Caveats related to visual quality and seasonal timing of historical photographs were important considerations in the interpretation of changes witnessed for headwater island braided systems, as well as for floodplain ponds. Development of rigorous, long-term, multi-scale monitoring techniques is necessary to guide the management and restoration of river-floodplain systems for the diversity of ecosystem services they provide.
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Nagler, Pamela; Glenn, Edward P.
2013-01-01
Tamarix leaf beetles (Diorhabda carinulata) have been widely released on western United States rivers to control introduced shrubs in the genus Tamarix, with the goals of saving water through removal of an assumed high water-use plant, and of improving habitat value by removing a competitor of native riparian trees. We review recent studies addressing three questions: (1) to what extent are Tamarix weakened or killed by recurrent cycles of defoliation; (2) can significant water salvage be expected from defoliation; and (3) what are the effects of defoliation on riparian ecology, particularly on avian habit? Defoliation has been patchy at many sites, and shrubs at some sites recover each year even after multiple years of defoliation. Tamarix evapotranspiration (ET) is much lower than originally assumed in estimates of potential water savings, and are the same or lower than possible replacement plants. There is concern that the endangered southwestern willow flycatcher (Empidonax trailli extimus) will be negatively affected by defoliation because the birds build nests early in the season when Tamarix is still green, but are still on their nests during the period of summer defoliation. Affected river systems will require continued monitoring and development of adaptive management practices to maintain or enhance riparian habitat values. Multiplatform remote sensing methods are playing an essential role in monitoring defoliation and rates of ET on affected river systems.
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Habitat and logistic support requirements for the initiation of a space manufacturing enterprise
NASA Technical Reports Server (NTRS)
Vajk, J. P.; Engel, J. H.; Shettler, J. A.
1979-01-01
A detailed scenario for the initiation of a space manufacturing enterprise using lunar materials to construct solar power satellites (SPS) was developed, with particular attention to habitat design and logistic support requirements. If SPS's can be constructed exclusively from lunar materials, the entire enterprise can be initiated in a 7 year period of launch activity (beginning as early as 1985) using the Space Shuttle and a low-cost, Shuttle-derived heavy lift vehicle. If additional chemical feedstocks must be imported from earth in significant quantities, it may be necessary to bring the next-generation launch vehicle (single-stage-to-orbit) into operation by 1991. The scenario presented features use of the mass-driver reaction engine for orbit-to-orbit transfer of cargos and makes extensive use of the expendable Shuttle external propellant tanks.
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Mereta, Seid Tiku; Yewhalaw, Delenasaw; Boets, Pieter; Ahmed, Abdulhakim; Duchateau, Luc; Speybroeck, Niko; Vanwambeke, Sophie O; Legesse, Worku; De Meester, Luc; Goethals, Peter L M
2013-11-04
A fundamental understanding of the spatial distribution and ecology of mosquito larvae is essential for effective vector control intervention strategies. In this study, data-driven decision tree models, generalized linear models and ordination analysis were used to identify the most important biotic and abiotic factors that affect the occurrence and abundance of mosquito larvae in Southwest Ethiopia. In total, 220 samples were taken at 180 sampling locations during the years 2010 and 2012. Sampling sites were characterized based on physical, chemical and biological attributes. The predictive performance of decision tree models was evaluated based on correctly classified instances (CCI), Cohen's kappa statistic (κ) and the determination coefficient (R2). A conditional analysis was performed on the regression tree models to test the relation between key environmental and biological parameters and the abundance of mosquito larvae. The decision tree model developed for anopheline larvae showed a good model performance (CCI = 84 ± 2%, and κ = 0.66 ± 0.04), indicating that the genus has clear habitat requirements. Anopheline mosquito larvae showed a widespread distribution and especially occurred in small human-made aquatic habitats. Water temperature, canopy cover, emergent vegetation cover, and presence of predators and competitors were found to be the main variables determining the abundance and distribution of anopheline larvae. In contrast, anopheline mosquito larvae were found to be less prominently present in permanent larval habitats. This could be attributed to the high abundance and diversity of natural predators and competitors suppressing the mosquito population densities. The findings of this study suggest that targeting smaller human-made aquatic habitats could result in effective larval control of anopheline mosquitoes in the study area. Controlling the occurrence of mosquito larvae via drainage of permanent wetlands may not be a good management
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2013-01-01
Background A fundamental understanding of the spatial distribution and ecology of mosquito larvae is essential for effective vector control intervention strategies. In this study, data-driven decision tree models, generalized linear models and ordination analysis were used to identify the most important biotic and abiotic factors that affect the occurrence and abundance of mosquito larvae in Southwest Ethiopia. Methods In total, 220 samples were taken at 180 sampling locations during the years 2010 and 2012. Sampling sites were characterized based on physical, chemical and biological attributes. The predictive performance of decision tree models was evaluated based on correctly classified instances (CCI), Cohen’s kappa statistic (κ) and the determination coefficient (R2). A conditional analysis was performed on the regression tree models to test the relation between key environmental and biological parameters and the abundance of mosquito larvae. Results The decision tree model developed for anopheline larvae showed a good model performance (CCI = 84 ± 2%, and κ = 0.66 ± 0.04), indicating that the genus has clear habitat requirements. Anopheline mosquito larvae showed a widespread distribution and especially occurred in small human-made aquatic habitats. Water temperature, canopy cover, emergent vegetation cover, and presence of predators and competitors were found to be the main variables determining the abundance and distribution of anopheline larvae. In contrast, anopheline mosquito larvae were found to be less prominently present in permanent larval habitats. This could be attributed to the high abundance and diversity of natural predators and competitors suppressing the mosquito population densities. Conclusions The findings of this study suggest that targeting smaller human-made aquatic habitats could result in effective larval control of anopheline mosquitoes in the study area. Controlling the occurrence of mosquito larvae via drainage
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Lunar Surface Habitat Configuration Assessment: Methodology and Observations
NASA Technical Reports Server (NTRS)
Carpenter, Amanda
2008-01-01
The Lunar Habitat Configuration Assessment evaluated the major habitat approaches that were conceptually developed during the Lunar Architecture Team II Study. The objective of the configuration assessment was to identify desired features, operational considerations, and risks to derive habitat requirements. This assessment only considered operations pertaining to the lunar surface and did not consider all habitat conceptual designs developed. To examine multiple architectures, the Habitation Focus Element Team defined several adequate concepts which warranted the need for a method to assess the various configurations. The fundamental requirement designed into each concept included the functional and operational capability to support a crew of four on a six-month lunar surface mission; however, other conceptual aspects were diverse in comparison. The methodology utilized for this assessment consisted of defining figure of merits, providing relevant information, and establishing a scoring system. In summary, the assessment considered the geometric configuration of each concept to determine the complexity of unloading, handling, mobility, leveling, aligning, mating to other elements, and the accessibility to the lunar surface. In theory, the assessment was designed to derive habitat requirements, potential technology development needs and identify risks associated with living and working on the lunar surface. Although the results were more subjective opposed to objective, the assessment provided insightful observations for further assessments and trade studies of lunar surface habitats. This overall methodology and resulting observations will be describe in detail and illustrative examples will be discussed.
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The forest ecosystem of southeast Alaska: 3. Fish habitats.
William R. Meehan
1974-01-01
The effects of logging and associated activities on fish habitat in southeastern Alaska are discussed, and fish habitat research applicable to southeast Alaska is summarized. Requirements of salmonids for suitable spawning and rearing areas are presented. Factors associated with timber harvest which may influence these habitats are discussed in detail; e.g., sediment,...
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Living in contained environments: Research implications from undersea habitats. [undersea habitats
NASA Technical Reports Server (NTRS)
Helmreich, Robert L.
1986-01-01
A cost-reward model is used to frame a discussion of differences in observed behavior of individuals and groups in confined environments. It has been observed that the high cost of functioning in a stressful environment is likely to produce poor performance when anticipated rewards are low but that participants can manage the stress and achieve high performance if they anticipate high rewards. The high-reward environment is exemplified by early undersea habitats such as Sealab and Tektite and by early space missions. Other aspects of behavior occur in all confined environments and point to an important area for future research. Of particular interest are intergroup conflicts arising between the confined group and its external control. Also, individual differences in personality seem always to have an impact in confined environments. Recent research has focused on: (1) predicting performance and adjustment based on instrumental and expressive aspects of the self; (2) the differential predictive power of achievement striving and irritation/irritability in Type A personalities; and (3) the nature and role of leadership in small, isolated groups.
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Determining habitat quality for species that demonstrate dynamic habitat selection
Beerens, James M.; Frederick, Peter C; Noonburg, Erik G; Gawlik, Dale E.
2015-01-01
Determining habitat quality for wildlife populations requires relating a species' habitat to its survival and reproduction. Within a season, species occurrence and density can be disconnected from measures of habitat quality when resources are highly seasonal, unpredictable over time, and patchy. Here we establish an explicit link among dynamic selection of changing resources, spatio-temporal species distributions, and fitness for predictive abundance and occurrence models that are used for short-term water management and long-term restoration planning. We used the wading bird distribution and evaluation models (WADEM) that estimate (1) daily changes in selection across resource gradients, (2) landscape abundance of flocks and individuals, (3) conspecific foraging aggregation, and (4) resource unit occurrence (at fixed 400 m cells) to quantify habitat quality and its consequences on reproduction for wetland indicator species. We linked maximum annual numbers of nests detected across the study area and nesting success of Great Egrets (Ardea alba), White Ibises (Eudocimus albus), and Wood Storks (Mycteria americana) over a 20-year period to estimated daily dynamics of food resources produced by WADEM over a 7490 km2 area. For all species, increases in predicted species abundance in March and high abundance in April were strongly linked to breeding responses. Great Egret nesting effort and success were higher when birds also showed greater conspecific foraging aggregation. Synthesis and applications: This study provides the first empirical evidence that dynamic habitat selection processes and distributions of wading birds over environmental gradients are linked with reproductive measures over periods of decades. Further, predictor variables at a variety of temporal (daily-multiannual) resolutions and spatial (400 m to regional) scales effectively explained variation in ecological processes that change habitat quality. The process used here allows managers to develop
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Deahn M. Donner; Christine A. Ribic; John R. Probst
2010-01-01
Habitat colonization and abandonment affects the distribution of a species in space and time, ultimately influencing the duration of time habitat is used and the total area of habitat occupied in any given year. Both aspects have important implications to long-term conservation planning. The importance of patch isolation and area to colonization-extinction events is...
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Habitat heterogeneity of hadal trenches: Considerations and implications for future studies
NASA Astrophysics Data System (ADS)
Stewart, Heather A.; Jamieson, Alan J.
2018-02-01
The hadal zone largely comprises a series of subduction trenches that do not form part of the continental shelf-slope rise to abyssal plain continuum. Instead they form geographically isolated clusters of deep-sea (6000-11,000 m water depth) environments. There is a growing realization in hadal science that ecological patterns and processes are not driven solely by responses to hydrostatic pressure, with comparable levels of habitat heterogeneity as observed in other marine biozones. Furthermore, this heterogeneity can be expressed at multiple scales from inter-trench levels (degrees of geographical isolation, and biochemical province), to intra-trench levels (variation between trench flanks and axis), topographical features within the trench interior (sedimentary basins, ridges, escarpments, 'deeps', seamounts) to the substrate of the trench floor (seabed-sediment composition, mass movement deposits, bedrock outcrop). Using best available bathymetry data combined with the largest lander-derived imaging dataset that spans the full depth range of three hadal trenches (including adjacent slopes); the Mariana, Kermadec and New Hebrides trenches, the topographic variability, fine-scale habitat heterogeneity and distribution of seabed sediments of these three trenches have been assessed for the first time. As well as serving as the first descriptive study of habitat heterogeneity at hadal depths, this study also provides guidance for future hadal sampling campaigns taking into account geographic isolation, total trench particulate organic matter flux, maximum water depth and area.
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The forest ecosystem of Southeast Alaska: 4. Wildlife habitats.
William R. Meehan
1974-01-01
The effects of logging and associated activities on the habitat of the major forest wildlife species in southeast Alaska are discussed and research results applicable to this region are summarized. Big game, furbearers, and non-game species are considered with respect to their habitat requirements and behavior. Recommendations are made for habitat management with...
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Auster, P.J.; Malatesta, R.J.; Langton, R.W.; Watling, Les; Valentine, P.C.; Donaldson, C.L.S.; Langton, E.W.; Shepard, A.N.; Babb, Ivar G.
1996-01-01
Fishing gear alters seafloor habitats, but the extent of these alterations, and their effects, have not been quantified extensively in the northwest Atlantic. Understanding the extent of these impacts, and their effects on populations of living marine resources, is needed to properly manage current and future levels of fishing effort and fishing power. For example, the entire U.S. side of the Gulf of Maine was impacted annually by mobile fishing gear between 1984 and 1990, based on calculations of area swept by trawl and dredge gear. Georges Bank was impacted three to nearly four times annually during the same period. Studies at three sites in the Gulf of Maine (off Swans Island, Jeffreys Bank, and Stellwagen Bank) showed that mobile fishing gear altered the physical structure (=complexity) of benthic habitats. Complexity was reduced by direct removal of biogenic (e.g., sponges, hydrozoans, bryozoans, amphipod tubes, holothurians, shell aggregates) and sedimentary (e.g., sand waves, depressions) structures. Also, removal of organisms that create structures (e.g., crabs, scallops) indirectly reduced complexity. Reductions in habitat complexity may lead to increased predation on juveniles of harvested species and ultimately recruitment to the harvestable stock. Because of a lack of reference sites, where use of mobile fishing is prohibited, no empirical studies have yet been conducted on a scale that could demonstrate population level effects of habitat-management options. If marine fisheries management is to evolve toward an ecosystem or habitat management approach, experiments are required on the effects of habitat change, both anthropogenic and natural.
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Intercohort density dependence drives brown trout habitat selection
NASA Astrophysics Data System (ADS)
Ayllón, Daniel; Nicola, Graciela G.; Parra, Irene; Elvira, Benigno; Almodóvar, Ana
2013-01-01
Habitat selection can be viewed as an emergent property of the quality and availability of habitat but also of the number of individuals and the way they compete for its use. Consequently, habitat selection can change across years due to fluctuating resources or to changes in population numbers. However, habitat selection predictive models often do not account for ecological dynamics, especially density dependent processes. In stage-structured population, the strength of density dependent interactions between individuals of different age classes can exert a profound influence on population trajectories and evolutionary processes. In this study, we aimed to assess the effects of fluctuating densities of both older and younger competing life stages on the habitat selection patterns (described as univariate and multivariate resource selection functions) of young-of-the-year, juvenile and adult brown trout Salmo trutta. We observed all age classes were selective in habitat choice but changed their selection patterns across years consistently with variations in the densities of older but not of younger age classes. Trout of an age increased selectivity for positions highly selected by older individuals when their density decreased, but this pattern did not hold when the density of younger age classes varied. It suggests that younger individuals are dominated by older ones but can expand their range of selected habitats when density of competitors decreases, while older trout do not seem to consider the density of younger individuals when distributing themselves even though they can negatively affect their final performance. Since these results may entail critical implications for conservation and management practices based on habitat selection models, further research should involve a wider range of river typologies and/or longer time frames to fully understand the patterns of and the mechanisms underlying the operation of density dependence on brown trout habitat
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Xiang, Zuo-Fu; Huo, Sheng; Xiao, Wen
2011-04-01
As anthropogenic habitat changes are often considered a threat to natural ecosystems and wildlife, a sound understanding of the effects of habitat alteration on endangered species is crucial when designing management strategies or performing conservation activities. Black-and-white snub-nosed monkeys (Rhinopithecus bieti) are categorized as endangered on the IUCN Red List and are endemic to the trans-Himalayas in China. At present, there are only 15 groups and 2,500 individuals remaining in the wild, and they are facing intense habitat degradation with selective logging for house building and firewood. Habitat deterioration through wood extraction is occurring at Xiaochangdu, Tibet, where one stable group of R. bieti lives in a marginal habitat in the northernmost part of the species' distribution. To understand the species' response to selective logging in an extremely marginal habitat, data on habitat preference and diet composition of a group of R. bieti were collected at Xiaochangdu from 2003 to 2005. The monkeys used different habitats nonrandomly during the year. The selection index for secondary conifer forest (SC), where selective logging has occurred, was the highest of all habitat types (>1), suggesting that the groups strongly preferred SC. The monkeys fed more on buds/leaves, more on flowers/fruit/seeds, and less on lichen in SC than in primary conifer forest (PC). Dietary diversity was significantly higher in SC than in PC. These results indicate that over the short term, low-intensity disturbances may result in increased foliage diversity that enable groups of R. bieti to survive in this marginal habitat. © 2010 Wiley-Liss, Inc.
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Matrix population models as a tool in development of habitat models
Gregory D. Hayward; David B. McDonald
1997-01-01
Building sophisticated habitat models for conservation of owls must stem from an understanding of the relative quality of habitats at a variety of geographic and temporal scales. Developing these models requires knowing the relationship between habitat conditions and owl performance. What measure should be used to compare the quality of habitats? Matrix population...
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Current practices in the identification of critical habitat for threatened species.
Camaclang, Abbey E; Maron, Martine; Martin, Tara G; Possingham, Hugh P
2015-04-01
The term critical habitat is used to describe the subset of habitat that is essential to the survival and recovery of species. Some countries legally require that critical habitat of listed threatened and endangered species be identified and protected. However, there is little evidence to suggest that the identification of critical habitat has had much impact on species recovery. We hypothesized that this may be due at least partly to a mismatch between the intent of critical habitat identification, which is to protect sufficient habitat for species persistence and recovery, and its practice. We used content analysis to systematically review critical habitat documents from the United States, Canada, and Australia. In particular, we identified the major trends in type of information used to identify critical habitat and in occupancy of habitat identified as critical. Information about population viability was used to identify critical habitat for only 1% of the species reviewed, and for most species, designated critical habitat did not include unoccupied habitat. Without reference to population viability, it is difficult to determine how much of a species' occupied and unoccupied habitat will be required for persistence. We therefore conclude that the identification of critical habitat remains inconsistent with the goal of protecting sufficient habitat to support persistence and recovery of the species. Ensuring that critical habitat identification aligns more closely with its intent will improve the accuracy of the designations and may therefore help improve the benefits to species recovery when combined with adequate implementation and enforcement of legal protections. © 2014 Society for Conservation Biology.
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Nutritional Differences between Two Orangutan Habitats: Implications for Population Density
Vogel, Erin R.; Harrison, Mark E.; Zulfa, Astri; Bransford, Timothy D.; Alavi, Shauhin E.; Husson, Simon; Morrogh-Bernard, Helen; Santiano; Firtsman, Twentinolosa; Utami-Atmoko, Sri Suci; van Noordwijk, Maria A.; Farida, Wartika Rosa
2015-01-01
Bottom-up regulatory factors have been proposed to exert a strong influence on mammalian population density. Studies relating habitat quality to population density have typically made comparisons among distant species or communities without considering variation in food quality among localities. We compared dietary nutritional quality of two Bornean orangutan populations with differing population densities in peatland habitats, Tuanan and Sabangau, separated by 63 km. We hypothesized that because Tuanan is alluvial, the plant species included in the orangutan diet would be of higher nutritional quality compared to Sabangau, resulting in higher daily caloric intake in Tuanan. We also predicted that forest productivity would be greater in Tuanan compared to Sabangau. In support of these hypotheses, the overall quality of the diet and the quality of matched dietary items were higher in Tuanan, resulting in higher daily caloric intake compared to Sabangau. These differences in dietary nutritional quality may provide insights into why orangutan population density is almost two times greater in Tuanan compared to Sabangau, in agreement with a potentially important influence of diet quality on primate population density. PMID:26466370
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Nutritional Differences between Two Orangutan Habitats: Implications for Population Density.
Vogel, Erin R; Harrison, Mark E; Zulfa, Astri; Bransford, Timothy D; Alavi, Shauhin E; Husson, Simon; Morrogh-Bernard, Helen; Santiano; Firtsman, Twentinolosa; Utami-Atmoko, Sri Suci; van Noordwijk, Maria A; Farida, Wartika Rosa
2015-01-01
Bottom-up regulatory factors have been proposed to exert a strong influence on mammalian population density. Studies relating habitat quality to population density have typically made comparisons among distant species or communities without considering variation in food quality among localities. We compared dietary nutritional quality of two Bornean orangutan populations with differing population densities in peatland habitats, Tuanan and Sabangau, separated by 63 km. We hypothesized that because Tuanan is alluvial, the plant species included in the orangutan diet would be of higher nutritional quality compared to Sabangau, resulting in higher daily caloric intake in Tuanan. We also predicted that forest productivity would be greater in Tuanan compared to Sabangau. In support of these hypotheses, the overall quality of the diet and the quality of matched dietary items were higher in Tuanan, resulting in higher daily caloric intake compared to Sabangau. These differences in dietary nutritional quality may provide insights into why orangutan population density is almost two times greater in Tuanan compared to Sabangau, in agreement with a potentially important influence of diet quality on primate population density.
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Adaptive breeding habitat selection: Is it for the birds?
Chalfoun, Anna D.; Schmidt, Kenneth A.
2012-01-01
The question of why animals choose particular habitats has important implications for understanding behavioral evolution and distribution of organisms in the wild and for delineating between habitats of different quality for conservation and management. Habitats chosen by animals can influence fitness outcomes via the costs (e.g., predation risk) and benefits (e.g., food availability) of habitat use. Habitat preferences should therefore be under selection to favor those that confer fitness advantages (Clark and Shutler 1999). Indeed, prevailing theory suggests that the habitat preferences of animals should be adaptive, such that fitness is higher in preferred habitats (Hildén 1965, Southwood 1977, Martin 1998). However, studies have often identified apparent mismatches between observed habitat preferences and fitness outcomes across a wide variety of taxa (Valladares and Lawton 1991, Mayhew 1997, Kolbe and Janzen 2002, Arlt and Pärt 2007, Mägi et al. 2009). Certainly, one limitation of studies may be that assessment of “fitness” is typically constrained to fitness surrogates such as nest success rather than lifetime reproductive success or classic Fisherian fitness (Endler 1986). Nevertheless, important habitat choices such as nest sites influence the probability that temporarily sedentary, dependent young are discovered by enemies such as predators and parasites. We therefore expect, on average, to see congruence between evolved habitat preferences and relevant components of fitness (e.g., nest success). Here, we (1) review the prevalence of apparent mismatches between avian breeding-habitat preferences and fitness outcomes using nest-site selection as a focus; (2) describe several potential mechanisms for such mismatches, including anthropogenic, methodological, and ecological–evolutionary; and (3) suggest a framework for understanding the contexts in which habitat preferences represent adaptive decisions, with a primary focus on ecological information
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Cullen, Laury; Stanton, Jessica C; Lima, Fernando; Uezu, Alexandre; Perilli, Miriam L L; Akçakaya, H Reşit
2016-01-01
Jaguar (Panthera onca) populations in the Upper Paraná River, in the Brazilian Atlantic Forest region, live in a landscape that includes highly fragmented areas as well as relatively intact ones. We developed a model of jaguar habitat suitability in this region, and based on this habitat model, we developed a spatially structured metapopulation model of the jaguar populations in this area to analyze their viability, the potential impact of road mortality on the populations' persistence, and the interaction between road mortality and habitat fragmentation. In more highly fragmented populations, density of jaguars per unit area is lower and density of roads per jaguar is higher. The populations with the most fragmented habitat were predicted to have much lower persistence in the next 100 years when the model included no dispersal, indicating that the persistence of these populations are dependent to a large extent on dispersal from other populations. This, in turn, indicates that the interaction between road mortality and habitat fragmentation may lead to source-sink dynamics, whereby populations with highly fragmented habitat are maintained only by dispersal from populations with less fragmented habitat. This study demonstrates the utility of linking habitat and demographic models in assessing impacts on species living in fragmented landscapes.
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Cullen, Laury; Stanton, Jessica C.; Lima, Fernando; Uezu, Alexandre; Perilli, Miriam L. L.; Akçakaya, H. Reşit
2016-01-01
Jaguar (Panthera onca) populations in the Upper Paraná River, in the Brazilian Atlantic Forest region, live in a landscape that includes highly fragmented areas as well as relatively intact ones. We developed a model of jaguar habitat suitability in this region, and based on this habitat model, we developed a spatially structured metapopulation model of the jaguar populations in this area to analyze their viability, the potential impact of road mortality on the populations' persistence, and the interaction between road mortality and habitat fragmentation. In more highly fragmented populations, density of jaguars per unit area is lower and density of roads per jaguar is higher. The populations with the most fragmented habitat were predicted to have much lower persistence in the next 100 years when the model included no dispersal, indicating that the persistence of these populations are dependent to a large extent on dispersal from other populations. This, in turn, indicates that the interaction between road mortality and habitat fragmentation may lead to source-sink dynamics, whereby populations with highly fragmented habitat are maintained only by dispersal from populations with less fragmented habitat. This study demonstrates the utility of linking habitat and demographic models in assessing impacts on species living in fragmented landscapes. PMID:27973584
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Hardman, Chloe J; Harrison, Dominic P G; Shaw, Pete J; Nevard, Tim D; Hughes, Brin; Potts, Simon G; Norris, Ken
2016-02-01
Restoration and maintenance of habitat diversity have been suggested as conservation priorities in farmed landscapes, but how this should be achieved and at what scale are unclear. This study makes a novel comparison of the effectiveness of three wildlife-friendly farming schemes for supporting local habitat diversity and species richness on 12 farms in England.The schemes were: (i) Conservation Grade (Conservation Grade: a prescriptive, non-organic, biodiversity-focused scheme), (ii) organic agriculture and (iii) a baseline of Entry Level Stewardship (Entry Level Stewardship: a flexible widespread government scheme). Conservation Grade farms supported a quarter higher habitat diversity at the 100-m radius scale compared to Entry Level Stewardship farms. Conservation Grade and organic farms both supported a fifth higher habitat diversity at the 250-m radius scale compared to Entry Level Stewardship farms. Habitat diversity at the 100-m and 250-m scales significantly predicted species richness of butterflies and plants. Habitat diversity at the 100-m scale also significantly predicted species richness of birds in winter and solitary bees. There were no significant relationships between habitat diversity and species richness for bumblebees or birds in summer.Butterfly species richness was significantly higher on organic farms (50% higher) and marginally higher on Conservation Grade farms (20% higher), compared with farms in Entry Level Stewardship. Organic farms supported significantly more plant species than Entry Level Stewardship farms (70% higher) but Conservation Grade farms did not (10% higher). There were no significant differences between the three schemes for species richness of bumblebees, solitary bees or birds. Policy implications . The wildlife-friendly farming schemes which included compulsory changes in management, Conservation Grade and organic, were more effective at increasing local habitat diversity and species richness compared with the less
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Crucial nesting habitat for gunnison sage-grouse: A spatially explicit hierarchical approach
Aldridge, Cameron L.; Saher, D.J.; Childers, T.M.; Stahlnecker, K.E.; Bowen, Z.H.
2012-01-01
Gunnison sage-grouse (Centrocercus minimus) is a species of special concern and is currently considered a candidate species under Endangered Species Act. Careful management is therefore required to ensure that suitable habitat is maintained, particularly because much of the species' current distribution is faced with exurban development pressures. We assessed hierarchical nest site selection patterns of Gunnison sage-grouse inhabiting the western portion of the Gunnison Basin, Colorado, USA, at multiple spatial scales, using logistic regression-based resource selection functions. Models were selected using Akaike Information Criterion corrected for small sample sizes (AIC c) and predictive surfaces were generated using model averaged relative probabilities. Landscape-scale factors that had the most influence on nest site selection included the proportion of sagebrush cover >5%, mean productivity, and density of 2 wheel-drive roads. The landscape-scale predictive surface captured 97% of known Gunnison sage-grouse nests within the top 5 of 10 prediction bins, implicating 57% of the basin as crucial nesting habitat. Crucial habitat identified by the landscape model was used to define the extent for patch-scale modeling efforts. Patch-scale variables that had the greatest influence on nest site selection were the proportion of big sagebrush cover >10%, distance to residential development, distance to high volume paved roads, and mean productivity. This model accurately predicted independent nest locations. The unique hierarchical structure of our models more accurately captures the nested nature of habitat selection, and allowed for increased discrimination within larger landscapes of suitable habitat. We extrapolated the landscape-scale model to the entire Gunnison Basin because of conservation concerns for this species. We believe this predictive surface is a valuable tool which can be incorporated into land use and conservation planning as well the assessment of
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Multi-scale habitat selection of the endangered Hawaiian Goose
Leopold, Christina R.; Hess, Steven C.
2013-01-01
After a severe population reduction during the mid-20th century, the endangered Hawaiian Goose (Branta sandvicensis), or Nēnē, has only recently re-established its seasonal movement patterns on Hawai‘i Island. Little is currently understood about its movements and habitat use during the nonbreeding season. The objectives of this research were to identify habitats preferred by two subpopulations of the Nēnē and how preferences shift seasonally at both meso-and fine scales. From 2009 to 2011, ten Nēnē ganders were outfitted with 40-to 45-g satellite transmitters with GPS capability. We used binary logistic regression to compare habitat use versus availability and an information-theoretic approach for model selection. Meso-scale habitat modeling revealed that Nēnē preferred exotic grass and human-modified landscapes during the breeding and molting seasons and native subalpine shrubland during the nonbreeding season. Fine-scale habitat modeling further indicated preference for exotic grass, bunch grass, and absence of trees. Proximity to water was important during molt, suggesting that the presence of water may provide escape from introduced mammalian predators while Nēnē are flightless. Finescale species-composition data added relatively little to understanding of Nēnē habitat preferences modeled at the meso scale, suggesting that the meso-scale is appropriate for management planning. Habitat selection during our study was consistent with historical records, although dissimilar from more recent studies of other subpopulations. Nēnē make pronounced seasonal movements between existing reserves and use distinct habitat types; understanding annual patterns has implications for the protection and restoration of important seasonal habitats.
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Generalisation of physical habitat-discharge relationships
NASA Astrophysics Data System (ADS)
Booker, D. J.; Acreman, M. C.
2007-01-01
Physical habitat is increasingly used worldwide as a measure of river ecosystem health when assessing changes to river flows, such as those caused by abstraction. The major drawback with this approach is that defining precisely the relationships between physical habitat and flow for a given river reach requires considerable data collection and analysis. Consequently, widely used models such as the Physical Habitat Simulation (PHABSIM) system are expensive to apply. There is, thus, a demand for rapid methods for defining habitat-discharge relationships from simple field measurements. This paper reports the analysis of data from 63 sites in the UK where PHABSIM has been applied. The results demonstrate that there are strong relationships between single measurements of channel form and river hydraulics and the habitat available for target species. The results can form the basis of a method to estimate sensitivity of physical habitat to flow change by visiting a site at only one flow. Furthermore, the uncertainty in estimates reduces as more information is collected. This allows the user to select the level of investment in data collection appropriate for the desired confidence in the estimates. The method is demonstrated using habitat indicators for different life stages of Atlantic salmon, brown trout, roach and dace.
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NASA Astrophysics Data System (ADS)
Pai, H.; Sivakumaran, K.; Villamizar, S. R.; Flanagan, J.; Guo, Q.; Harmon, T. C.
2013-12-01
Balancing ecosystem health in water-scarce, agriculturally dominated river basins remains a challenge. In dry water years, maintaining conditions for restored and sustained indigenous fish populations (a frequently used indicator for ecosystem health) is particularly challenging. Competing human demands include urban and agricultural water supplies, hydropower, and flood control. In many semi-arid regions, increasing drought intensity and frequency under future climate scenarios will combine with population increases to water scarcity. The goal of this work is to better understand how reservoir releases affect fish habitat and overall river aquatic ecosystem quality. Models integrating a diverse array of physical and biological processes and system state are used to forecast the river ecosystem response to changing drivers. We propose a distributed parameter-based Habitat Suitability Index (HSI) approach for assessing fish habitat quality. Our river ecosystem HSI maps are based on a combination of the following: (1) In situ data describing stream flow and water quality conditions; (2) Spatial observations, including surveyed cross-sections, aerial imagery and digital elevation maps (DEM) of the river and its riparian corridor; and (3) Simulated spatially distributed water depths, flow velocities, and temperatures estimated from 1D and 2D river flow and temperature models (HEC-RAS and CE-QUAL-W2, respectively). With respect to (2), image processing schemes are used to classify and map key habitat features, namely riparian edge and shallow underwater vegetation. HSI maps can be modified temporally to address specific life cycle requirements of indicator fish species. Results are presented for several reaches associated with the San Joaquin River Restoration Project, focusing on several components of the Chinook salmon life cycle. HSI maps and interpretations are presented in the context of a range of prescribed reservoir release hydrographs linked to California water
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The California Wildlife/Fish Habitat Relationship System
William E. Grenfell; Hal Salwasser; William F. Laudenslayer
1982-01-01
The California Wildlife/Fish Habitat Relationships (WFHR) System is an ongoing effort to apply our knowledge of wildlife habitat requirements to identify and explain the consequences of proposed land use activities, particularly those activities that affect vegetation. The U.S. Forest Service initiated the WFHR program in California in 1976 and has developed it for all...
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Concepts for manned lunar habitats
NASA Technical Reports Server (NTRS)
Hypes, W. D.; Butterfield, A. J.; King, C. B.; Qualls, G. D.; Davis, W. T.; Gould, M. J.; Nealy, J. E.; Simonsen, L. C.
1991-01-01
The design philosophy that will guide the design of early lunar habitats will be based on a compromise between the desired capabilities of the base and the economics of its development and implantation. Preferred design will be simple, make use of existing technologies, require the least amount of lunar surface preparation, and minimize crew activity. Three concepts for an initial habitat supporting a crew of four for 28 to 30 days are proposed. Two of these are based on using Space Station Freedom structural elements modified for use in a lunar-gravity environment. A third concept is proposed that is based on an earlier technology based on expandable modules. The expandable modules offer significant advantages in launch mass and packaged volume reductions. It appears feasible to design a transport spacecraft lander that, once landed, can serve as a habitat and a stand-off for supporting a regolith environmental shield. A permanent lunar base habitat supporting a crew of twelve for an indefinite period can be evolved by using multiple initial habitats. There appears to be no compelling need for an entirely different structure of larger volume and increased complexity of implantation.
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Quantitative analysis of American woodcock nest and brood habitat
Bourgeois, A.; Keppie, Daniel M.; Owen, Ray B.
1977-01-01
Sixteen nest and 19 brood sites of American woodcock (Philohela minoI) were examined in northern lower Michigan between 15 April and 15 June 1974 to determine habitat structure associated with these sites. Woodcock hens utilized young, second-growth forest stands which were similar in species composition for both nesting and brood rearing. A multi-varIate discriminant function analysis revealed a significant (P< 0.05) difference, however, in habitat structure. Nest habitat was characterized by lower tree density (2176 trees/ha) and basal area (8.6 m2/ha), by being close to forest openings (7 m) and by being situated on dry, relatively well drained sites. In contrast, woodcock broods were located in sites that had nearly twice the tree density (3934 trees/hal and basal area (16.5 m2/ha), was located over twice as far from forest openings (18 m) and generally occurred on damp sites, near (8 m) standing water. Importance of the habitat features to the species and possible management implications are discussed.
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Linn, Catherine Anne; Griebeler, Eva Maria
2016-08-01
In Germany, the thermophilic European mantid (Mantis religiosa L.) is endangered. Here, we study habitat requirements during its life, and discuss the applicability of the two conservation measures grazing and mowing to this insect species. At two study sites in south-western Germany, which were each subject to one of these measures, we recorded structural and climatic conditions within different microhabitats. We also conducted capture-mark-recapture studies for adult M. religiosa, and mapped adult roosting, oothecae deposition, egg hatching, and imaginal molting in microhabitats over two vegetation periods. In order to assess microhabitat preference of M. religiosa during its life, and identify climatic conditions driving preferences, we applied the Lille habitat preference index and conducted logistic regression analysis for life phases. Our results suggest that temperature is important for egg and nymph development. For egg deposition, females preferred solid substrates with high heat-storing capacities, as those attenuate the negative influence of cold weather periods on egg development. Being ambush predators, males and females preferred roosting sites with sufficient shelter and high prey abundance. Contrary to our expectation, the conservation measures reduced adult population sizes, and presumably reproduction rates. We thus suggest that mowing during the adult phase should reduce vegetation height to a moderate level to keep prey abundance high. Mowing with a clearing saw or grazing over a short period in small fenced areas should be preferred over prolonged grazing, as grazers collaterally stamp down the vegetation. Grazers indirectly reduce prey availability by deteriorating prevailing microclimatic conditions. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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Survival in patchy landscapes: the interplay between dispersal, habitat loss and fragmentation
Niebuhr, Bernardo B. S.; Wosniack, Marina E.; Santos, Marcos C.; Raposo, Ernesto P.; Viswanathan, Gandhimohan M.; da Luz, Marcos G. E.; Pie, Marcio R.
2015-01-01
Habitat loss and fragmentation are important factors determining animal population dynamics and spatial distribution. Such landscape changes can lead to the deleterious impact of a significant drop in the number of species, caused by critically reduced survival rates for organisms. In order to obtain a deeper understanding of the threeway interplay between habitat loss, fragmentation and survival rates, we propose here a spatially explicit multi-scaled movement model of individuals that search for habitat. By considering basic ecological processes, such as predation, starvation (outside the habitat area), and competition, together with dispersal movement as a link among habitat areas, we show that a higher survival rate is achieved in instances with a lower number of patches of larger areas. Our results demonstrate how movement may counterbalance the effects of habitat loss and fragmentation in altered landscapes. In particular, they have important implications for conservation planning and ecosystem management, including the design of specific features of conservation areas in order to enhance landscape connectivity and population viability. PMID:26148488
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Geospatial interface and model for predicting potential seagrass habitat
Restoration of ecosystem services provided by seagrass habitats in estuaries requires a clear understanding of the modes of action of multiple interacting stressors including nutrients, climate change, coastal land-use change, and habitat modification. We have developed a geos...
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Reproductive success of migratory birds in habitat sources and sinks
Therese M. Donovan; Frank R. , III Thompson; John Faaborg; John R. Probst
1995-01-01
Fragmentation of breeding habitat in North America has been implicated in the decline of forest-nesting, Neotropical migrant birds. We used a comparative approach to examine the effects of fragmentation on three forest-nesting migrants: Ovenbird (Seiurus aurocapillus), Red-eyed Vireo (Vireo ofivaceus), and Wood Thrush (...
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Habitat-based constraints on food web structure and parasite life cycles.
Rossiter, Wayne; Sukhdeo, Michael V K
2014-04-01
Habitat is frequently implicated as a powerful determinant of community structure and species distributions, but few studies explicitly evaluate the relationship between habitat-based patterns of species' distributions and the presence or absence of trophic interactions. The complex (multi-host) life cycles of parasites are directly affected by these factors, but almost no data exist on the role of habitat in constraining parasite-host interactions at the community level. In this study the relationship(s) between species abundances, distributions and trophic interactions (including parasitism) were evaluated in the context of habitat structure (classic geomorphic designations of pools, riffles and runs) in a riverine community (Raritan River, Hunterdon County, NJ, USA). We report 121 taxa collected over a 2-year period, and compare the observed food web patterns to null model expectations. The results show that top predators are constrained to particular habitat types, and that species' distributions are biased towards pool habitats. However, our null model (which incorporates cascade model assumptions) accurately predicts the observed patterns of trophic interactions. Thus, habitat strongly dictates species distributions, and patterns of trophic interactions arise as a consequence of these distributions. Additionally, we find that hosts utilized in parasite life cycles are more overlapping in their distributions, and this pattern is more pronounced among those involved in trophic transmission. We conclude that habitat structure may be a strong predictor of parasite transmission routes, particularly within communities that occupy heterogeneous habitats.
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Coherence between harvest and habitat management -- Joint venture perspectives
Baxter, C.K.; Nelson, J.W.; Reinecke, K.J.; Stephens, S.E.
2006-01-01
Introduction: In recent months, an ad hoc group of waterfowl scientists, representing the International Association of Fish and Wildlife Agencies (IAFWA) Adaptive Harvest Management (ARM) Task Force and the North American Waterfowl Management Plan (NAWMP) Committee, have collaborated as a Joint Task Group (JTG) to assess options for unifying the population goals guiding waterfowl harvest management and habitat management. The JTG has been charged with bringing coherence to the population goals of the two programs. Characterizing the problem as one of coherence indicates value judgments exist regarding its significance or perhaps existence. For purposes of this paper, we characterize the lack of coherence as the absence of consistent population goals in the two related components of waterfowl conservation habitat and harvest management. Our purpose is to support continued dialogue on the respective goals of these programs and the possible implications of discordant goals to habitat joint ventures. Our objectives are two-fold: (1) illustrate how NAWMP habitat management goals and strategies have been interpreted and pursued in both breeding and wintering areas, and (2) provide perspectives on the linkages between regional habitat management programs and harvest management. The Lower Mississippi Valley and the Prairie Pothole joint ventures (LMVJV and PPJV, respectively) will be used as examples.
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Handley, Kim M; Lloyd, Jonathan R
2013-01-01
The Marinobacter genus comprises widespread marine bacteria, found in localities as diverse as the deep ocean, coastal seawater and sediment, hydrothermal settings, oceanic basalt, sea-ice, sand, solar salterns, and oil fields. Terrestrial sources include saline soil and wine-barrel-decalcification wastewater. The genus was designated in 1992 for the Gram-negative, hydrocarbon-degrading bacterium Marinobacter hydrocarbonoclasticus. Since then, a further 31 type strains have been designated. Nonetheless, the metabolic range of many Marinobacter species remains largely unexplored. Most species have been classified as aerobic heterotrophs, and assessed for limited anaerobic pathways (fermentation or nitrate reduction), whereas studies of low-temperature hydrothermal sediments, basalt at oceanic spreading centers, and phytoplankton have identified species that possess a respiratory repertoire with significant biogeochemical implications. Notable physiological traits include nitrate-dependent Fe(II)-oxidation, arsenic and fumarate redox cycling, and Mn(II) oxidation. There is also evidence for Fe(III) reduction, and metal(loid) detoxification. Considering the ubiquity and metabolic capabilities of the genus, Marinobacter species may perform an important and underestimated role in the biogeochemical cycling of organics and metals in varied marine habitats, and spanning aerobic-to-anoxic redox gradients.
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Handley, Kim M.; Lloyd, Jonathan R.
2013-01-01
The Marinobacter genus comprises widespread marine bacteria, found in localities as diverse as the deep ocean, coastal seawater and sediment, hydrothermal settings, oceanic basalt, sea-ice, sand, solar salterns, and oil fields. Terrestrial sources include saline soil and wine-barrel-decalcification wastewater. The genus was designated in 1992 for the Gram-negative, hydrocarbon-degrading bacterium Marinobacter hydrocarbonoclasticus. Since then, a further 31 type strains have been designated. Nonetheless, the metabolic range of many Marinobacter species remains largely unexplored. Most species have been classified as aerobic heterotrophs, and assessed for limited anaerobic pathways (fermentation or nitrate reduction), whereas studies of low-temperature hydrothermal sediments, basalt at oceanic spreading centers, and phytoplankton have identified species that possess a respiratory repertoire with significant biogeochemical implications. Notable physiological traits include nitrate-dependent Fe(II)-oxidation, arsenic and fumarate redox cycling, and Mn(II) oxidation. There is also evidence for Fe(III) reduction, and metal(loid) detoxification. Considering the ubiquity and metabolic capabilities of the genus, Marinobacter species may perform an important and underestimated role in the biogeochemical cycling of organics and metals in varied marine habitats, and spanning aerobic-to-anoxic redox gradients. PMID:23734151
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Introduction to stream network habitat analysis
Bartholow, John M.; Waddle, Terry J.
1986-01-01
Increasing demands on stream resources by a variety of users have resulted in an increased emphasis on studies that evaluate the cumulative effects of basinwide water management programs. Network habitat analysis refers to the evaluation of an entire river basin (or network) by predicting its habitat response to alternative management regimes. The analysis principally focuses on the biological and hydrological components of the riv er basin, which include both micro- and macrohabitat. (The terms micro- and macrohabitat are further defined and discussed later in this document.) Both conceptual and analytic models are frequently used for simplifying and integrating the various components of the basin. The model predictions can be used in developing management recommendations to preserve, restore, or enhance instream fish habitat. A network habitat analysis should begin with a clear and concise statement of the study objectives and a thorough understanding of the institutional setting in which the study results will be applied. This includes the legal, social, and political considerations inherent in any water management setting. The institutional environment may dictate the focus and level of detail required of the study to a far greater extent than the technical considerations. After the study objectives, including species on interest, and institutional setting are collectively defined, the technical aspects should be scoped to determine the spatial and temporal requirements of the analysis. A macro level approach should be taken first to identify critical biological elements and requirements. Next, habitat availability is quantified much as in a "standard" river segment analysis, with the likely incorporation of some macrohabitat components, such as stream temperature. Individual river segments may be aggregated to represent the networkwide habitat response of alternative water management schemes. Things learned about problems caused or opportunities generated may
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Hook, T.O.; Rutherford, E.S.; Croley, T.E.; Mason, D.M.; Madenjian, C.P.
2008-01-01
The identification of important spawning and nursery habitats for fish stocks can aid fisheries management, but is complicated by various factors, including annual variation in recruitment success. The alewife (Alosa pseudoharengus) is an ecologically important species in Lake Michigan that utilizes a variety of habitats for spawning and early life growth. While productive, warm tributary mouths (connected to Lake Michigan) may contribute disproportionately more recruits (relative to their habitat volume) to the adult alewife population than cooler, less productive nearshore habitats, the extent of interannual variation in the relative contributions of recruits from these two habitat types remains unknown. We used an individual-based bioenergetics simulation model and input data on daily temperatures to estimate alewife recruitment to the adult population by these different habitat types. Simulations suggest that nearshore lake habitats typically produce the vast majority of young alewife recruits. However, tributary habitats may contribute the majority of alewife recruits during years of low recruitment. We suggest that high interannual variation in the relative importance of habitats for recruitment is a common phenomenon, which should be considered when developing habitat management plans for fish populations. ?? 2008 NRC.
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Competition and niche separation of pelagic bacteria in freshwater habitats.
Pernthaler, Jakob
2017-06-01
Freshwater bacterioplankton assemblages are composed of sympatric populations that can be delineated, for example, by ribosomal RNA gene relatedness and that differ in key ecophysiological properties. They may be free-living or attached, specialized for particular concentrations or subsets of substrates, or invest a variable amount of their resources in defence traits against protistan predators and viruses. Some may be motile and tactic whereas others are not, with far-reaching implications for their respective life styles and niche partitioning. The co-occurrence of competitors with overlapping growth requirements has profound consequences for the stability of community functions; it can to some extent be explained by habitat factors such as the microscale complexity and spatiotemporal variability of the lacustrine environments. On the other hand, the composition and diversity of freshwater microbial assemblages also reflects non-equilibrium states, dispersal and the stochasticity of community assembly processes. This review synoptically discusses the competition and niche separation of heterotrophic bacterial populations (defined at various levels of phylogenetic resolution) in the pelagic zone of inland surface waters from a variety of angles, focusing on habitat heterogeneity and the resulting biogeographic distribution patterns, the ecophysiological adaptations to the substrate field and the interactions of prokaryotes with predators and viruses. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.
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Florally rich habitats reduce insect pollination and the reproductive success of isolated plants.
Evans, Tracie M; Cavers, Stephen; Ennos, Richard; Vanbergen, Adam J; Heard, Matthew S
2017-08-01
Landscape heterogeneity in floral communities has the potential to modify pollinator behavior. Pollinator foraging varies with the diversity, abundance, and spatial configuration of floral resources. However, the implications of this variation for pollen transfer and ultimately the reproductive success of insect pollinated plants remains unclear, especially for species which are rare or isolated in the landscape. We used a landscape-scale experiment, coupled with microsatellite genotyping, to explore how the floral richness of habitats affected pollinator behavior and pollination effectiveness. Small arrays of the partially self-compatible plant Californian poppy ( Eschscholzia californica) were introduced across a landscape gradient to simulate rare, spatially isolated populations. The effects on pollinator activity, outcrossing, and plant reproduction were measured. In florally rich habitats, we found reduced pollen movement between plants, leading to fewer long-distance pollination events, lower plant outcrossing, and a higher incidence of pollen limitation. This pattern indicates a potential reduction in per capita pollinator visitation, as suggested by the lower activity densities and richness of pollinators observed within florally rich habitats. In addition, seed production reduced by a factor of 1.8 in plants within florally rich habitats and progeny germination reduced by a factor of 1.2. We show this to be a consequence of self-fertilization within the partially self-compatible plant, E. californica . These findings indicate that locally rare plants are at a competitive disadvantage within florally rich habitats because neighboring plant species disrupt conspecific mating by co-opting pollinators. Ultimately, this Allee effect may play an important role in determining the long-term persistence of rarer plants in the landscape, both in terms of seed production and viability. Community context therefore requires consideration when designing and
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Seasonal habitat requirements for sage-grouse: spring, summer, fall, and winter
Clait E. Braun; John W. Connelly; Michael A. Schroeder
2005-01-01
Sage-grouse (Centrocercus minimus, C. urophasianus) are dependent upon live sagebrush (Artemisia spp.) for all life processes across their entire range. This paper describes habitats used by sage-grouse as documented in the scientific literature. The leaves of sagebrush are eaten by sage-grouse throughout the...
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A Rapid Approach to Modeling Species-Habitat Relationships
NASA Technical Reports Server (NTRS)
Carter, Geoffrey M.; Breinger, David R.; Stolen, Eric D.
2005-01-01
A growing number of species require conservation or management efforts. Success of these activities requires knowledge of the species' occurrence pattern. Species-habitat models developed from GIS data sources are commonly used to predict species occurrence but commonly used data sources are often developed for purposes other than predicting species occurrence and are of inappropriate scale and the techniques used to extract predictor variables are often time consuming and cannot be repeated easily and thus cannot efficiently reflect changing conditions. We used digital orthophotographs and a grid cell classification scheme to develop an efficient technique to extract predictor variables. We combined our classification scheme with a priori hypothesis development using expert knowledge and a previously published habitat suitability index and used an objective model selection procedure to choose candidate models. We were able to classify a large area (57,000 ha) in a fraction of the time that would be required to map vegetation and were able to test models at varying scales using a windowing process. Interpretation of the selected models confirmed existing knowledge of factors important to Florida scrub-jay habitat occupancy. The potential uses and advantages of using a grid cell classification scheme in conjunction with expert knowledge or an habitat suitability index (HSI) and an objective model selection procedure are discussed.
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Auster, Peter J.; Malatesta, Richard J.; Langton, Richard W.; Watting, Les; Valentine, Page C.; Donaldson, Carol Lee S.; Langton, Elizabeth W.; Shepard, Andrew N.; Babb, War G.
1997-01-01
Fishing gear alters seafloor habitats, but the extent of these alterations, and their effects, have not been quantified extensively in the northwest Atlantic. Understanding the extent of these impacts, and their effects on populations of living marine resources, is needed to properly manage current and future levels of fishing effort and fishing power. For example, the entire U.S. side of the Gulf of Maine was impacted annually by mobile fishing gear between 1984 and 1990, based on calculations of area swept by trawl and dredge gear. Georges Bank was imparted three to nearly four times annually during the same period. Studies at three sites in the Gulf of Maine (off Swans Island, Jeffreys Bank, and Stellwagen Bank) showed that mobile fishing gear altered the physical structure (=complexity) of benthic habitats. Complexity was reduced by direct removal of biogenic (e.g., sponges, hydrozoans, bryozoans, amphipod tubes, holothurians, shell aggregates) and‐ sedimentary (e.g., sand waves, depressions) structures. Also, removal of organisms that create.structures (e.g., crabs, scallops) indirectly reduced complexity. Reductions in habitat complexity may lead to increased predation on juveniles of harvested species and ultimately recruitment to the harvestable stock. Because of a lack of reference sites, where use of mobile fishing is prohibited, no empirical studies have yet been conducted on a scale that could demonstrate population level effects of habitat‐management options. If marine fisheries management is to evolve toward an ecosystem or habitat management approach, experiments are required on the effects of habitat change, both anthropogenic and natural.
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NASA Technical Reports Server (NTRS)
Capps, Stephen; Lorandos, Jason; Akhidime, Eval; Bunch, Michael; Lund, Denise; Moore, Nathan; Murakawa, Kiosuke
1989-01-01
The purpose of this study is to investigate comprehensive design requirements associated with designing habitats for humans in a partial gravity environment, then to apply them to a lunar base design. Other potential sites for application include planetary surfaces such as Mars, variable-gravity research facilities, and a rotating spacecraft. Design requirements for partial gravity environments include locomotion changes in less than normal earth gravity; facility design issues, such as interior configuration, module diameter, and geometry; and volumetric requirements based on the previous as well as psychological issues involved in prolonged isolation. For application to a lunar base, it is necessary to study the exterior architecture and configuration to insure optimum circulation patterns while providing dual egress; radiation protection issues are addressed to provide a safe and healthy environment for the crew; and finally, the overall site is studied to locate all associated facilities in context with the habitat. Mission planning is not the purpose of this study; therefore, a Lockheed scenario is used as an outline for the lunar base application, which is then modified to meet the project needs. The goal of this report is to formulate facts on human reactions to partial gravity environments, derive design requirements based on these facts, and apply the requirements to a partial gravity situation which, for this study, was a lunar base.
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James M. Guldin; John Strom; Warren Montague; Larry D. Hedrick
2004-01-01
National Forest managers in the Interior Highlands of Arkansas are restoring 155,000 acres of unburned shortleaf pine stands to shortleaf pine-bluestem habitat. Habitat restoration consists of longer rotations, removal of midstory hardwoods, and reintroduction of fire. A study was installed in the spring of 2000 to evaluate shortleaf pine regeneration and overstory...
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An Alternative to Adaptation by Sexual Selection: Habitat Choice.
Porter, Cody K; Akcali, Christopher K
2018-06-09
Adaptation in mating signals and preferences has generally been explained by sexual selection. We propose that adaptation in such mating traits might also arise via a non-mutually exclusive process wherein individuals preferentially disperse to habitats where they experience high mating performance. Here we explore the evolutionary implications of this process. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Marshall, Leon; Carvalheiro, Luísa G; Aguirre-Gutiérrez, Jesús; Bos, Merijn; de Groot, G Arjen; Kleijn, David; Potts, Simon G; Reemer, Menno; Roberts, Stuart; Scheper, Jeroen; Biesmeijer, Jacobus C
2015-10-01
Species distribution models (SDM) are increasingly used to understand the factors that regulate variation in biodiversity patterns and to help plan conservation strategies. However, these models are rarely validated with independently collected data and it is unclear whether SDM performance is maintained across distinct habitats and for species with different functional traits. Highly mobile species, such as bees, can be particularly challenging to model. Here, we use independent sets of occurrence data collected systematically in several agricultural habitats to test how the predictive performance of SDMs for wild bee species depends on species traits, habitat type, and sampling technique. We used a species distribution modeling approach parametrized for the Netherlands, with presence records from 1990 to 2010 for 193 Dutch wild bees. For each species, we built a Maxent model based on 13 climate and landscape variables. We tested the predictive performance of the SDMs with independent datasets collected from orchards and arable fields across the Netherlands from 2010 to 2013, using transect surveys or pan traps. Model predictive performance depended on species traits and habitat type. Occurrence of bee species specialized in habitat and diet was better predicted than generalist bees. Predictions of habitat suitability were also more precise for habitats that are temporally more stable (orchards) than for habitats that suffer regular alterations (arable), particularly for small, solitary bees. As a conservation tool, SDMs are best suited to modeling rarer, specialist species than more generalist and will work best in long-term stable habitats. The variability of complex, short-term habitats is difficult to capture in such models and historical land use generally has low thematic resolution. To improve SDMs' usefulness, models require explanatory variables and collection data that include detailed landscape characteristics, for example, variability of crops and
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Diurnal stream habitat use of juvenile Atlantic salmon, brown trout and rainbow trout in winter
Johnson, J. H.; Douglass, K.A.
2009-01-01
The diurnal winter habitat of three species of juvenile salmonids was examined in a tributary of Skaneateles Lake, NY to compare habitat differences among species and to determine if species/age classes were selecting specific habitats. A total of 792 observations were made on the depth, velocity, substrate and cover (amount and type) used by sympatric subyearling Atlantic salmon, subyearling brown trout and subyearling and yearling rainbow trout. Subyearling Atlantic salmon occurred in shallower areas with faster velocities and less cover than the other salmonid groups. Subyearling salmon was also the only group associated with substrate of a size larger than the average size substrate in the study reach during both winters. Subyearling brown trout exhibited a preference for vegetative cover. Compared with available habitat, yearling rainbow trout were the most selective in their habitat use. All salmonid groups were associated with more substrate cover in 2002 under high flow conditions. Differences in the winter habitat use of these salmonid groups have important management implications in terms of both habitat protection and habitat enhancement.
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An assessment of stream habitat and nutrients in the Elwha River basin: implications for restoration
Munn, Mark D.; Black, R.W.; Haggland, A.L.; Hummling, M.A.; Huffman, R.L.
1999-01-01
The Elwha River was once famous for its 10 runs of anadromous salmon which included chinook that reportedly exceeded 45 kilograms. These runs either ceased to exist or were significantly depleted after the construction of the Elwha (1912) and Glines Canyon (1927) Dams, which resulted in the blockage of more than 113 kilometers of mainstem river and tributary habitat. In 1992, in response to the loss of the salmon runs in the Elwha River Basin, President George Bush signed the Elwha River Ecosystem and Fisheries Restoration Act, which authorizes the Secretary of the Interior to remove both dams for ecosystem restoration. The objective of this U.S. Geological Survey (USGS) study was to begin describing baseline conditions for assessing changes that will result from restoration. The first step was to review available physical, chemical, and biological information on the Elwha River Basin. We found that most studies have focused on anadromous fish and habitat and that little information is available on water quality, habitat classification, geomorphic processes, and riparian and aquatic biological communities. There is also a lack of sufficient data on baseline conditions for assessing future changes if restoration occurs. The second component of this study was to collect water-quality and habitat data, filling information gaps. This information will permit a better understanding of the relation between physical habitat and nutrient conditions and changes that may result from salmon restoration. We collected data in the fall of 1997 and found that the concentrations of nitrogen and phosphorous were generally low, with most samples having concentrations below detection limits. Detectable concentrations of nitrogen were associated with sites in the lower reach of the Elwha River, whereas the few detections of phosphorus were at sites throughout the basin. Nutrient data indicate that the Elwha River and its tributaries are oligotrophic. Results of the stream
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Espinoza, Mario; Cappo, Mike; Heupel, Michelle R; Tobin, Andrew J; Simpfendorfer, Colin A
2014-01-01
Quantifying shark distribution patterns and species-specific habitat associations in response to geographic and environmental drivers is critical to assessing risk of exposure to fishing, habitat degradation, and the effects of climate change. The present study examined shark distribution patterns, species-habitat associations, and marine reserve use with baited remote underwater video stations (BRUVS) along the entire Great Barrier Reef Marine Park (GBRMP) over a ten year period. Overall, 21 species of sharks from five families and two orders were recorded. Grey reef Carcharhinus amblyrhynchos, silvertip C. albimarginatus, tiger Galeocerdo cuvier, and sliteye Loxodon macrorhinus sharks were the most abundant species (>64% of shark abundances). Multivariate regression trees showed that hard coral cover produced the primary split separating shark assemblages. Four indicator species had consistently higher abundances and contributed to explaining most of the differences in shark assemblages: C. amblyrhynchos, C. albimarginatus, G. cuvier, and whitetip reef Triaenodon obesus sharks. Relative distance along the GBRMP had the greatest influence on shark occurrence and species richness, which increased at both ends of the sampling range (southern and northern sites) relative to intermediate latitudes. Hard coral cover and distance across the shelf were also important predictors of shark distribution. The relative abundance of sharks was significantly higher in non-fished sites, highlighting the conservation value and benefits of the GBRMP zoning. However, our results also showed that hard coral cover had a large effect on the abundance of reef-associated shark species, indicating that coral reef health may be important for the success of marine protected areas. Therefore, understanding shark distribution patterns, species-habitat associations, and the drivers responsible for those patterns is essential for developing sound management and conservation approaches.
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External Device to Incrementally Skid the Habitat (E-DISH)
NASA Technical Reports Server (NTRS)
Brazell, J. W.; Introne, Steve; Bedell, Lisa; Credle, Ben; Holp, Graham; Ly, Siao; Tait, Terry
1994-01-01
A Mars habitat transport system was designed as part of the NASA Mars exploration program. The transport system, the External Device to Incrementally Skid the Habitat (E - DISH), will be used to transport Mars habitats from their landing sites to the colony base and will be detached after unloading. The system requirements for Mars were calculated and scaled for model purposes. Specific model materials are commonly found and recommendations for materials for the Mars design are included.
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Temporally dynamic habitat suitability predicts genetic relatedness among caribou.
Yannic, Glenn; Pellissier, Loïc; Le Corre, Maël; Dussault, Christian; Bernatchez, Louis; Côté, Steeve D
2014-10-07
Landscape heterogeneity plays a central role in shaping ecological and evolutionary processes. While species utilization of the landscape is usually viewed as constant within a year, the spatial distribution of individuals is likely to vary in time in relation to particular seasonal needs. Understanding temporal variation in landscape use and genetic connectivity has direct conservation implications. Here, we modelled the daily use of the landscape by caribou in Quebec and Labrador, Canada and tested its ability to explain the genetic relatedness among individuals. We assessed habitat selection using locations of collared individuals in migratory herds and static occurrences from sedentary groups. Connectivity models based on habitat use outperformed a baseline isolation-by-distance model in explaining genetic relatedness, suggesting that variations in landscape features such as snow, vegetation productivity and land use modulate connectivity among populations. Connectivity surfaces derived from habitat use were the best predictors of genetic relatedness. The relationship between connectivity surface and genetic relatedness varied in time and peaked during the rutting period. Landscape permeability in the period of mate searching is especially important to allow gene flow among populations. Our study highlights the importance of considering temporal variations in habitat selection for optimizing connectivity across heterogeneous landscape and counter habitat fragmentation. © 2014 The Author(s) Published by the Royal Society. All rights reserved.
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Espinoza, Mario; Cappo, Mike; Heupel, Michelle R.; Tobin, Andrew J.; Simpfendorfer, Colin A.
2014-01-01
Quantifying shark distribution patterns and species-specific habitat associations in response to geographic and environmental drivers is critical to assessing risk of exposure to fishing, habitat degradation, and the effects of climate change. The present study examined shark distribution patterns, species-habitat associations, and marine reserve use with baited remote underwater video stations (BRUVS) along the entire Great Barrier Reef Marine Park (GBRMP) over a ten year period. Overall, 21 species of sharks from five families and two orders were recorded. Grey reef Carcharhinus amblyrhynchos, silvertip C. albimarginatus, tiger Galeocerdo cuvier, and sliteye Loxodon macrorhinus sharks were the most abundant species (>64% of shark abundances). Multivariate regression trees showed that hard coral cover produced the primary split separating shark assemblages. Four indicator species had consistently higher abundances and contributed to explaining most of the differences in shark assemblages: C. amblyrhynchos, C. albimarginatus, G. cuvier, and whitetip reef Triaenodon obesus sharks. Relative distance along the GBRMP had the greatest influence on shark occurrence and species richness, which increased at both ends of the sampling range (southern and northern sites) relative to intermediate latitudes. Hard coral cover and distance across the shelf were also important predictors of shark distribution. The relative abundance of sharks was significantly higher in non-fished sites, highlighting the conservation value and benefits of the GBRMP zoning. However, our results also showed that hard coral cover had a large effect on the abundance of reef-associated shark species, indicating that coral reef health may be important for the success of marine protected areas. Therefore, understanding shark distribution patterns, species-habitat associations, and the drivers responsible for those patterns is essential for developing sound management and conservation approaches. PMID
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Use of Non-Riparian Habitats by Least Bell's Vireos
Barbara E. Kus; Karen L. Miner
1989-01-01
The least Bell's vireo (Vireo bellii pusillus) is an endangered songbird inhabiting riparian woodlands in southern California. Although the species requires riparian habitats for nesting, vireos also occur in upland habitats adjacent to breeding areas. Vireos breeding at the Sweetwater River in San Diego County during 1986 and 1987 were observed...
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Eppley, Timothy M; Donati, Giuseppe; Ramanamanjato, Jean-Baptiste; Randriatafika, Faly; Andriamandimbiarisoa, Laza N; Rabehevitra, David; Ravelomanantsoa, Robertin; Ganzhorn, Jörg U
2015-01-01
The lemurs of Madagascar are among the most threatened mammalian taxa in the world, with habitat loss due to shifting cultivation and timber harvest heavily contributing to their precarious state. Deforestation often leads to fragmentation, resulting in mixed-habitat matrices throughout a landscape where disturbed areas are prone to invasion by exotic plants. Our study site, the Mandena littoral forest (southeast Madagascar), is a matrix of littoral forest, littoral swamp, and Melaleuca swamp habitats. Here, Melaleuca quinquenervia has invaded the wetland ecosystem, creating a mono-dominant habitat that currently provides the only potential habitat corridor between forest fragments. We sought to understand the role of this invasive Melaleuca swamp on the behavioral ecology of a threatened, small-bodied folivore, the southern bamboo lemur (Hapalemur meridionalis). We collected botanical and behavioral data on four groups of H. meridionalis between January and December 2013. Our results confirm Melaleuca swamp as an important part of their home range: while lemurs seasonally limited activities to certain habitats, all groups were capable of utilizing this invasive habitat for feeding and resting. Furthermore, the fact that Hapalemur use an invasive plant species as a dispersal corridor increases our knowledge of their ecological flexibility, and may be useful in the conservation management of remaining threatened populations.
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Eppley, Timothy M.; Donati, Giuseppe; Ramanamanjato, Jean-Baptiste; Randriatafika, Faly; Andriamandimbiarisoa, Laza N.; Rabehevitra, David; Ravelomanantsoa, Robertin; Ganzhorn, Jörg U.
2015-01-01
The lemurs of Madagascar are among the most threatened mammalian taxa in the world, with habitat loss due to shifting cultivation and timber harvest heavily contributing to their precarious state. Deforestation often leads to fragmentation, resulting in mixed-habitat matrices throughout a landscape where disturbed areas are prone to invasion by exotic plants. Our study site, the Mandena littoral forest (southeast Madagascar), is a matrix of littoral forest, littoral swamp, and Melaleuca swamp habitats. Here, Melaleuca quinquenervia has invaded the wetland ecosystem, creating a mono-dominant habitat that currently provides the only potential habitat corridor between forest fragments. We sought to understand the role of this invasive Melaleuca swamp on the behavioral ecology of a threatened, small-bodied folivore, the southern bamboo lemur (Hapalemur meridionalis). We collected botanical and behavioral data on four groups of H. meridionalis between January and December 2013. Our results confirm Melaleuca swamp as an important part of their home range: while lemurs seasonally limited activities to certain habitats, all groups were capable of utilizing this invasive habitat for feeding and resting. Furthermore, the fact that Hapalemur use an invasive plant species as a dispersal corridor increases our knowledge of their ecological flexibility, and may be useful in the conservation management of remaining threatened populations. PMID:26536667
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Stratification of habitats for identifying habitat selection by Merriam's turkeys
Mark A. Rumble; Stanley H. Anderson
1992-01-01
Habitat selection patterns of Merriamâs Turkeys were compared in hierarchical analyses of three levels of habitat stratification. Habitat descriptions in first-level analyses were based on dominant species of vegetation. Habitat descriptions in second-level analyses were based on dominant species of vegetation and overstory canopy cover. Habitat descriptions in third-...
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Decision analysis for habitat conservation of an endangered, range-limited salamander
Robinson, Orin J.; McGowan, Conor P.; Apodaca, J.J.
2016-01-01
Many species of conservation concern are habitat limited and often a major focus of management for these species is habitat acquisition and/or restoration. Deciding the location of habitat restoration or acquisition to best benefit a protected species can be a complicated subject with competing management objectives, ecological uncertainties and stochasticity. Structured decision making (SDM) could be a useful approach for explicitly incorporating those complexities while still working toward species conservation and/or recovery. We applied an SDM approach to Red Hills salamander Phaeognathus hubrichti habitat conservation decision making. Phaeognathus hubrichti is a severely range-limited endemic species in south central Alabama and has highly specific habitat requirements. Many known populations live on private lands and the primary mode of habitat protection is habitat conservation planning, but such plans are non-binding and not permanent. Working with stakeholders, we developed an objectives hierarchy linking land acquisition or protection actions to fundamental objectives. We built a model to assess and compare the quality of the habitat in the known range of P. hubrichti. Our model evaluated key habitat attributes of 5814 pixels of 1 km2 each and ranked the pixels from best to worst with respect to P. hubrichti habitat requirements. Our results are a spatially explicit valuation of each pixel, with respect to its probable benefit to P. hubrichti populations. The results of this effort will be used to rank pixels from most to least beneficial, then identify land owners in the most useful areas for salamanders who are willing to sell or enter into a permanent easement agreement.
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Carlisle, Jason D.; Chalfoun, Anna D.; Smith, Kurt T.; Beck, Jeffery L.
2018-01-01
The “umbrella species” concept is a conservation strategy in which creating and managing reserve areas to meet the needs of one species is thought to benefit other species indirectly. Broad-scale habitat protections on behalf of an umbrella species are assumed to benefit co-occurring taxa, but targeted management actions to improve local habitat suitability for the umbrella species may produce unintended effects on other species. Our objective was to quantify the effects of a common habitat treatment (mowing of big sagebrush [Artemisia tridentata]) intended to benefit a high-profile umbrella species (Greater Sage-Grouse [Centrocercus urophasianus]) on 3 sympatric songbird species of concern. We used a before–after control-impact experimental design spanning 3 yr in Wyoming, USA, to quantify the effect of mowing on the abundance, nest-site selection, nestling condition, and nest survival of 2 sagebrush-obligate songbirds (Brewer's Sparrow [Spizella breweri] and Sage Thrasher [Oreoscoptes montanus]) and one open-habitat generalist songbird (Vesper Sparrow [Pooecetes gramineus]). Mowing was associated with lower abundance of Brewer's Sparrows and Sage Thrashers but higher abundance of Vesper Sparrows. We found no Brewer's Sparrows or Sage Thrashers nesting in the mowed footprint posttreatment, which suggests complete loss of nesting habitat for these species. Mowing was associated with higher nestling condition and nest survival for Vesper Sparrows but not for the sagebrush-obligate species. Management prescriptions that remove woody biomass within a mosaic of intact habitat may be tolerated by sagebrush-obligate songbirds but are likely more beneficial for open-habitat generalist species. By definition, umbrella species conservation entails habitat protections at broad spatial scales. We caution that habitat manipulations to benefit Greater Sage-Grouse could negatively affect nontarget species of conservation concern if implemented across large spatial extents.
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NASA Astrophysics Data System (ADS)
Snyder, Noah P.; Castele, Michael R.; Wright, Jed R.
2009-02-01
The rivers of coastal Maine flow through mainstem lakes and long low-gradient reaches that break the continuum of bedload transport expected in nonparaglacial landscapes. Stream erosion of glacial deposits supplies coarse sediment to these systems. The land use history includes intensive timber harvest and associated dam construction, which may have altered the frequency of substrate-mobilizing events. These watersheds are vital habitat for the last remaining wild anadromous Atlantic salmon in the United States. Future adjustments in channel morphology and habitat quality (via natural stream processes or restoration projects) depend on erosion, transport, and deposition of coarse sediment. These factors motivate our study of competence at four sites in the Sheepscot and Narraguagus watersheds. Three of the four sites behaved roughly similarly, with particle entrainment during intervals that include winter ice and spring flood conditions, and relatively minor bed mobilization during moderate floods in the summer and fall (with a recurrence interval of 2-3 years). The fourth site, on the Sheepscot River mainstem, exhibits more vigorous entrainment of marked particles and more complex three-dimensional channel morphology. This contrast is partially due to local geomorphic conditions that favor high shear stresses (particularly relatively steep gradient), but also likely to nourishment of the bedload saltation system by recruitment from an eroding glacial deposit upstream. Our results suggest that the frequency and magnitude of bedload transport are reach specific, depending on factors including local channel geometry, upstream sediment supply and transport, and formation of anchor ice. This presents a challenge for stream practitioners in this region: different reaches may require contrasting management strategies. Our results underscore the importance of understanding channel processes at a given site and assessing conditions upstream and downstream as a prerequisite
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Seasonal habitat associations of the wolverine in central Idaho
Jeffrey P. Copeland; James M. Peek; Craig R. Groves; Wayne E. Melquist; Kevin S. Mckelvey; Gregory W. McDaniel; Clinton D. Long; Charles E. Harris
2007-01-01
Although understanding habitat relationships remains fundamental to guiding wildlife management, these basic prerequisites remain vague and largely unstudied for the wolverine. Currently, a study of wolverine ecology conducted in Montana, USA, in the 1970s is the sole source of information on habitat requirements of wolverines in the conterminous United States. The...
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The effects of wetland habitat structure on Florida apple snail density
Karunaratne, L.B.; Darby, P.C.; Bennetts, R.E.
2006-01-01
Wetlands often support a variety of juxtaposed habitat patches (e.g., grass-, shrub- or tree-dominated) differentially suited to support the inhabiting fauna. The proportion of available habitat types has been affected by human activity and consequently has contributed to degrading habitat quality for some species. The Florida apple snail (Pomacea paludosa) has drawn attention as a critical prey item for wetlands wildlife and as an indicator of wetlands restoration success in peninsular Florida, USA. An apparent contradiction has evolved wherein this species appears intolerant of drying events, but these disturbances may be necessary to maintain suitable habitat structure for apple snails. We recently reported that assertions regarding intolerance to dry downs in this species were inaccurate. Here, we compared snail density in habitats with (wet prairie) and without (slough) emergent macrophytes, as well as evaluating the effects of structural attributes within the broad wet prairie habitat type. Snail densities were greater in prairies relative to sloughs (??2= 12.90, df=1, P=0.0003), often by a factor of two to three. Within wet prairie habitats, we found greater snail densities in Panicum hemitomon as compared to Eleocharis cellulosa (??2=31.45, df=1, P=0.0001). Significantly fewer snails were found in dense E. cellulosa as compared to habitats with lower stem density (??2= 10.73, df=1, P=0.011). Our results indicate that wet prairie habitat supports greater snail densities than nymphaea-dominatd slough. Our results have implications for wetlands water management in that continuous inundation has been shown to convert wet prairie to slough habitat, and we suggest this should be avoided in support of apple snails and their predators. ?? 2006, The Society of Wetland Scientists.
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Saproxylic Hemiptera Habitat Associations
Michael D. Ulyshen; James L. Hanula; Robert L. Blinn; Gene. Kritsky
2012-01-01
Understanding the habitat requirements of organisms associated with dead wood is important in order to conserve them in managed forests. Unfortunately, many of the less diverse saproxylic taxa, including Hemiptera, remain largely unstudied. An effort to rear insects from dead wood taken from two forest types (an upland pine-dominated and a bottomland mixed hardwood),...
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Habitat conditions associated with lynx hunting behavior during winter in northern Washington
Benjamin T. Maletzke; Gary M. Koehler; Robert B. Wielgus; Keith B. Aubry; Marc A. Evans
2008-01-01
Effectively managing habitat for threatened populations of Canada lynx (Lynx canadensis) requires knowledge of habitat conditions that provide for the ecological needs of lynx. We snow-tracked lynx to identify habitat conditions associated with hunting behavior and predation during winters of 2002-2003 and 2003-2004 in the northern Cascade Range in...
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Environmental variation between habitats and uptake of heavy metals by Urtica dioica.
Otte, M L; Wijte, A H
1993-12-01
The observation from previous surveys, that Urtica dioica plants that had grown in metal contaminated soil in the floodplains of the former Rhine estuary in different habitats, but at comparable total soil metal concentrations, showed significant differences in tissue metal concentrations, led to the hypothesis that variation in other environmental characteristics than soil composition and chemical speciation of metals between habitats is also important in determining uptake and translocation of metals in plants. A field survey indicated that differences in root Cd, Cu and Zn concentrations might partly be explained by variation in speciation of metals in different habitats. However, shoot concentrations showed a different pattern that did not relate to variation in soil metal concentrations. In a habitat experiment Urtica dioica plants were grown in artificially contaminated soil in pots that were placed in the four habitats (grassland, pure reed, mixed reed, osier bed) that were also included in the field survey. After seven weeks the plants showed significant differences in Cu and Zn concentrations in roots and aboveground plant parts and in distribution of the metals in the plants between habitats. It was concluded that variation between habitats in environmental characteristics other than soil composition can explain as much variation in plants as can variation in soil metal concentrations and/or speciation. The implications for assessment of soil metal contamination and uptake by plants are discussed.
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Webster, Mike M.; Atton, Nicola; Hart, Paul J. B.; Ward, Ashley J. W.
2011-01-01
Habitat-specific morphological variation, often corresponding to resource specialization, is well documented in freshwater fishes. In this study we used landmark based morphometric analyses to investigate morphological variation among threespine sticklebacks (Gasterosteus aculeatus L.) from four interconnected habitat types within a single lowland drainage basin in eastern England. These included the upper and lower reaches of the river, the estuary, a connected ditch network and a coastal salt marsh. We found significant habitat-specific differences in morphology, with three axes of variation describing differences in orbit diameter, body depth, caudal peduncle shape and pectoral fin positioning as well as variation in relative dorsal and pelvic spine size. Interestingly, the ditch system, an artificial and heavily managed habitat, is populated by sticklebacks with a characteristic morphology, suggesting that human management of habitats can in some circumstances lead to morphological variation among the animals that inhabit them. We discuss the mechanisms that conceivably underlie the observed morphological variation and the further work necessary to identify them. Finally, we consider the implications of habitat-specific body shape variation for the behavioural ecology of this ecologically generalist species. PMID:21698269
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Croak, Benjamin M.; Crowther, Mathew S.; Webb, Jonathan K.; Shine, Richard
2013-01-01
A detailed understanding of how extensively animals move through the landscape, and the habitat features upon which they rely, can identify conservation priorities and thus inform management planning. For many endangered species, information on habitat use either is sparse, or is based upon studies from a small part of the species’ range. The broad-headed snake (Hoplocephalus bungaroides) is restricted to a specialized habitat (sandstone outcrops and nearby forests) within a small geographic range in south-eastern Australia. Previous research on this endangered taxon was done at a single site in the extreme south of the species’ geographic range. We captured and radio-tracked 9 adult broad-headed snakes at sites in the northern part of the species’ distribution, to evaluate the generality of results from prior studies, and to identify critical habitat components for this northern population. Snakes spent most of winter beneath sun-warmed rocks then shifted to tree hollows in summer. Thermal regimes within retreat-sites support the hypothesis that this shift is thermally driven. Intervals between successive displacements were longer than in the southern snakes but dispersal distances per move and home ranges were similar. Our snakes showed non-random preferences both in terms of macrohabitat (e.g., avoidance of some vegetation types) and microhabitat (e.g., frequent use of hollow-bearing trees). Despite many consistencies, the ecology of this species differs enough between southern and northern extremes of its range that managers need to incorporate information on local features to most effectively conserve this threatened reptile. PMID:23613912
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Croak, Benjamin M; Crowther, Mathew S; Webb, Jonathan K; Shine, Richard
2013-01-01
A detailed understanding of how extensively animals move through the landscape, and the habitat features upon which they rely, can identify conservation priorities and thus inform management planning. For many endangered species, information on habitat use either is sparse, or is based upon studies from a small part of the species' range. The broad-headed snake (Hoplocephalus bungaroides) is restricted to a specialized habitat (sandstone outcrops and nearby forests) within a small geographic range in south-eastern Australia. Previous research on this endangered taxon was done at a single site in the extreme south of the species' geographic range. We captured and radio-tracked 9 adult broad-headed snakes at sites in the northern part of the species' distribution, to evaluate the generality of results from prior studies, and to identify critical habitat components for this northern population. Snakes spent most of winter beneath sun-warmed rocks then shifted to tree hollows in summer. Thermal regimes within retreat-sites support the hypothesis that this shift is thermally driven. Intervals between successive displacements were longer than in the southern snakes but dispersal distances per move and home ranges were similar. Our snakes showed non-random preferences both in terms of macrohabitat (e.g., avoidance of some vegetation types) and microhabitat (e.g., frequent use of hollow-bearing trees). Despite many consistencies, the ecology of this species differs enough between southern and northern extremes of its range that managers need to incorporate information on local features to most effectively conserve this threatened reptile.
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Joseph L. Ganey; William M. Block; Jeffrey S. Jenness; Randolph A. Wilson
1998-01-01
To better understand the habitat relationships of the Mexican spotted owl (Strix occidentalis lucida), and how such relationships might influence forest management, we studied home-range and habitat use of radio-marked owls in ponderosa pine (Pinus ponderosa) Gambel oak (Quercus gambelii) forest. Annual home-range size (95% adaptive-kernel estimate) averaged 895 ha...
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Earth is a Marine Habitat. Habitat Conservation Program.
ERIC Educational Resources Information Center
National Oceanic and Atmospheric Administration (DOC), Rockville, MD.
This brochure is intended to educate the public about the need to conserve and preserve the earth's environment (man's habitat). It contains an introduction to the ocean world and threats to coastal habitat. Photos and narrative revolve around the theme "Earth is a Marine Habitat." Sections include: "The Web of…
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Discrete choice modeling of shovelnose sturgeon habitat selection in the Lower Missouri River
Bonnot, T.W.; Wildhaber, M.L.; Millspaugh, J.J.; DeLonay, A.J.; Jacobson, R.B.; Bryan, J.L.
2011-01-01
Substantive changes to physical habitat in the Lower Missouri River, resulting from intensive management, have been implicated in the decline of pallid (Scaphirhynchus albus) and shovelnose (S. platorynchus) sturgeon. To aid in habitat rehabilitation efforts, we evaluated habitat selection of gravid, female shovelnose sturgeon during the spawning season in two sections (lower and upper) of the Lower Missouri River in 2005 and in the upper section in 2007. We fit discrete choice models within an information theoretic framework to identify selection of means and variability in three components of physical habitat. Characterizing habitat within divisions around fish better explained selection than habitat values at the fish locations. In general, female shovelnose sturgeon were negatively associated with mean velocity between them and the bank and positively associated with variability in surrounding depths. For example, in the upper section in 2005, a 0.5 m s-1 decrease in velocity within 10 m in the bank direction increased the relative probability of selection 70%. In the upper section fish also selected sites with surrounding structure in depth (e.g., change in relief). Differences in models between sections and years, which are reinforced by validation rates, suggest that changes in habitat due to geomorphology, hydrology, and their interactions over time need to be addressed when evaluating habitat selection. Because of the importance of variability in surrounding depths, these results support an emphasis on restoring channel complexity as an objective of habitat restoration for shovelnose sturgeon in the Lower Missouri River.
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Selection of nest-site habitat by interior least terns in relation to sandbar construction
Sherfy, M.H.; Stucker, J.H.; Buhl, D.A.
2012-01-01
Federally endangered interior least terns (Sternula antillarum) nest on bare or sparsely vegetated sandbars on midcontinent river systems. Loss of nesting habitat has been implicated as a cause of population declines, and managing these habitats is a major initiative in population recovery. One such initiative involves construction of mid-channel sandbars on the Missouri River, where natural sandbar habitat has declined in quantity and quality since the late 1990s. We evaluated nest-site habitat selection by least terns on constructed and natural sandbars by comparing vegetation, substrate, and debris variables at nest sites (na =a 798) and random points (na =a 1,113) in bare or sparsely vegetated habitats. Our logistic regression models revealed that a broader suite of habitat features was important in nest-site selection on constructed than on natural sandbars. Odds ratios for habitat variables indicated that avoidance of habitat features was the dominant nest-site selection process on both sandbar types, with nesting terns being attracted to nest-site habitat features (gravel and debris) and avoiding vegetation only on constructed sandbars, and avoiding silt and leaf litter on both sandbar types. Despite the seemingly uniform nature of these habitats, our results suggest that a complex suite of habitat features influences nest-site choice by least terns. However, nest-site selection in this social, colonially nesting species may be influenced by other factors, including spatial arrangement of bare sand habitat, proximity to other least terns, and prior habitat occupancy by piping plovers (Charadrius melodus). We found that nest-site selection was sensitive to subtle variation in habitat features, suggesting that rigor in maintaining habitat condition will be necessary in managing sandbars for the benefit of least terns. Further, management strategies that reduce habitat features that are avoided by least terns may be the most beneficial to nesting least terns
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Selection of nest-site habitat by interior least terns in relation to sandbar construction
Sherfy, Mark H.; Stucker, Jennifer H.; Buhl, Deborah A.
2012-01-01
Federally endangered interior least terns (Sternula antillarum) nest on bare or sparsely vegetated sandbars on midcontinent river systems. Loss of nesting habitat has been implicated as a cause of population declines, and managing these habitats is a major initiative in population recovery. One such initiative involves construction of mid-channel sandbars on the Missouri River, where natural sandbar habitat has declined in quantity and quality since the late 1990s. We evaluated nest-site habitat selection by least terns on constructed and natural sandbars by comparing vegetation, substrate, and debris variables at nest sites (n = 798) and random points (n = 1,113) in bare or sparsely vegetated habitats. Our logistic regression models revealed that a broader suite of habitat features was important in nest-site selection on constructed than on natural sandbars. Odds ratios for habitat variables indicated that avoidance of habitat features was the dominant nest-site selection process on both sandbar types, with nesting terns being attracted to nest-site habitat features (gravel and debris) and avoiding vegetation only on constructed sandbars, and avoiding silt and leaf litter on both sandbar types. Despite the seemingly uniform nature of these habitats, our results suggest that a complex suite of habitat features influences nest-site choice by least terns. However, nest-site selection in this social, colonially nesting species may be influenced by other factors, including spatial arrangement of bare sand habitat, proximity to other least terns, and prior habitat occupancy by piping plovers (Charadrius melodus). We found that nest-site selection was sensitive to subtle variation in habitat features, suggesting that rigor in maintaining habitat condition will be necessary in managing sandbars for the benefit of least terns. Further, management strategies that reduce habitat features that are avoided by least terns may be the most beneficial to nesting least terns.
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Akers, Alice A; Anwarul Islam, Md; Nijman, Vincent
2013-10-01
Conserving a species depends on an understanding of its habitat requirements. Primatologists often characterize the habitat requirements of primates using macroscale population-based approaches relying on correlations between habitat attributes and population abundances between sites with varying levels of disturbance. This approach only works for species spread between several populations. The populations of some primates do not fulfill these criteria, forcing researchers to rely on individual-based (microscale) rather than population-based approaches for habitat characterization. We examined the reliability of using micro-scale habitat characterizations by studying the microhabitat preferences of a group of wild western hoolock gibbons (Hoolock hoolock) in order to compare our results to the habitat preferences of western hoolock gibbons identified during a macroscale study of populations across Bangladesh. We used stepwise discriminant analysis to differentiate between the areas of low, medium, and high usage based on microhabitat characteristics (tree species availability, altitude, canopy connection, distance from forest edge, and levels of human disturbance). The gibbons used interior forest habitat with low food tree availability most frequently for sleeping and socializing, and used edge habitat containing high food tree availability for medium periods for feeding. These results indicate that the gibbons prefer interior forest but are frequently forced to visit the forest edge to feed. Therefore, the optimal habitat would be interior forest away from human disturbance with high sleeping-tree and feeding-tree availability. These habitat preferences are consistent with the habitat attributes of Bangladesh's largest remaining western hoolock gibbon populations, which live in areas containing low agricultural encroachment and high food-tree availability. Microhabitat use studies can be used to characterize the habitat requirements of a species, but should
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Condition varies with habitat choice in postbreeding forest birds
Scott H. Stoleson
2013-01-01
Many birds that are experiencing population declines require extensive tracts of mature forest habitat for breeding. Recent work suggests that at least some may shift their habitat use to early-successional areas after nesting but before migration. I used constant-effort mist netting in regenerating clearcuts (4-8 years postcut) and dense mature-forest understories to...
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The global distribution of deep-water Antipatharia habitat
NASA Astrophysics Data System (ADS)
Yesson, Chris; Bedford, Faye; Rogers, Alex D.; Taylor, Michelle L.
2017-11-01
Antipatharia are a diverse group of corals with many species found in deep water. Many Antipatharia are habitat for associates, have extreme longevity and some species can occur beyond 8500 m depth. As they are major constituents of'coral gardens', which are Vulnerable Marine Ecosystems (VMEs), knowledge of their distribution and environmental requirements is an important pre-requisite for informed conservation planning particularly where the expense and difficulty of deep-sea sampling prohibits comprehensive surveys. This study uses a global database of Antipatharia distribution data to perform habitat suitability modelling using the Maxent methodology to estimate the global extent of black coral habitat suitability. The model of habitat suitability is driven by temperature but there is notable influence from other variables of topography, surface productivity and oxygen levels. This model can be used to predict areas of suitable habitat, which can be useful for conservation planning. The global distribution of Antipatharia habitat suitability shows a marked contrast with the distribution of specimen observations, indicating that many potentially suitable areas have not been sampled, and that sampling effort has been disproportionate to shallow, accessible areas inside marine protected areas (MPAs). Although 25% of Antipatharia observations are located in MPAs, only 7-8% of predicted suitable habitat is protected, which is short of the Convention on Biological Diversity target to protect 10% of ocean habitats by 2020.
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Concepts for a Shroud or Propellant Tank Derived Deep Space Habitat
NASA Technical Reports Server (NTRS)
Howard, Robert L.
2012-01-01
Long duration human spaceflight missions beyond Low Earth Orbit will require much larger spacecraft than capsules such as the Russian Soyuz or American Orion Multi-Purpose Crew Vehicle. A concept spacecraft under development is the Deep Space Habitat, with volumes approaching that of space stations such as Skylab, Mir, and the International Space Station. This paper explores several concepts for Deep Space Habitats constructed from a launch vehicle shroud or propellant tank. It also recommends future research using mockups and prototypes to validate the size and crew station capabilities of such a habitat. Keywords: Exploration, space station, lunar outpost, NEA, habitat, long duration, deep space habitat, shroud, propellant tank.
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Manning, Tom; Hagar, Joan C.
2011-01-01
The American pika (Ochotona princeps Richardson) has long been characterized in field guides and popular literature as an obligate inhabitant of alpine talus and as having relatively low dispersal capability. However, recent work reveals pikas to have broader habitat associations than previously reported. Over a large portion of the western slope of the Cascade Range in Oregon, pikas inhabit relatively low-elevation sites far from alpine areas and frequently occur in rocky man-made habitats such as roadcuts or rock quarries. We present observations of pikas in these previously overlooked habitats and discuss implications for (1) the proposed listing of the American pika as an endangered or threatened species; (2) furthering our understanding of pika population dynamics, habitat associations, and dispersal capabilites; and (3) management of federal, state, and private forest lands.
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CisLunar Habitat Internal Architecture Design Criteria
NASA Technical Reports Server (NTRS)
Jones, R.; Kennedy, K.; Howard, R.; Whitmore, M.; Martin, C.; Garate, J.
2017-01-01
Lunar Habitat Internal Architecture Study is to become a forcing function to establish a common understanding of CisLunar Phase-1 Habitation Internal Architecture design criteria, processes, and tools. The scope of the CisLunar Habitat Internal Architecture study is to design, develop, demonstrate, and evaluate a Phase-1 CisLunar Habitat common module internal architecture based on design criteria agreed to by NASA, the International Partners, and Commercial Exploration teams. This task is to define the CisLunar Phase-1 Internal Architecture Government Reference Design, assist NASA in becoming a "smart buyer" for Phase-1 Habitat Concepts, and ultimately to derive standards and requirements from the Internal Architecture Design Process. The first step was to define a Habitat Internal Architecture Design Criteria and create a structured philosophy to be used by design teams as a filter by which critical aspects of consideration would be identified for the purpose of organizing and utilizing interior spaces. With design criteria in place, the team will develop a series of iterative internal architecture concept designs which will be assessed by means of an evaluation criteria and process. These assessments will successively drive and refine the design, leading to the combination and down-selection of design concepts. A single refined reference design configuration will be developed into in a medium-to-high fidelity mockup. A multi-day human-in-the-loop mission test will fully evaluate the reference design and validate its configuration. Lessons learned from the design and evaluation will enable the team to identify appropriate standards for Phase-1 CisLunar Habitat Internal Architecture and will enable NASA to develop derived requirements in support of maturing CisLunar Habitation capabilities. This paper will describe the criteria definition process, workshop event, and resulting CisLunar Phase-1 Habitat Internal Architecture Design Criteria.
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Advantages of a Modular Mars Surface Habitat Approach
NASA Technical Reports Server (NTRS)
Rucker, Michelle A.; Hoffman, Stephan J.; Andrews, Alida; Watts, Kevin
2018-01-01
Early crewed Mars mission concepts developed by the National Aeronautics and Space Administration (NASA) assumed a single, large habitat would house six crew members for a 500-day Mars surface stay. At the end of the first mission, all surface equipment, including the habitat, -would be abandoned and the process would be repeated at a different Martian landing site. This work was documented in a series of NASA publications culminating with the Mars Design Reference Mission 5.0 (NASA-SP-2009-566). The Evolvable Mars Campaign (EMC) explored whether re-using surface equipment at a single landing site could be more affordable than the Apollo-style explore-abandon-repeat mission cadence. Initial EMC assumptions preserved the single, monolithic habitat, the only difference being a new requirement to reuse the surface habitat for multiple expedition crews. A trade study comparing a single large habitat versus smaller, modular habitats leaned towards the monolithic approach as more mass-efficient. More recent work has focused on the operational aspects of building up Mars surface infrastructure over multiple missions, and has identified compelling advantages of the modular approach that should be considered before making a final decision. This paper explores Mars surface mission operational concepts and integrated system analysis, and presents an argument for the modular habitat approach.
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Parker, Gene W.; Armstrong, David S.; Richards, Todd A.
2004-01-01
Four methods used to determine streamflow requirements for habitat protection at nine critical riffle reaches in the Assabet River and Charles River Basins were compared. The methods include three standard setting techniques?R2Cross, Wetted Perimeter, and Tennant?and a diagnostic method, the Range of Variability Approach. One study reach is on the main stem of the Assabet River, four reaches are on tributaries to the Assabet River (Cold Harbor Brook, Danforth Brook, Fort Meadow Brook, and Elizabeth Brook), three are on the main stem of the Charles River, and one is on a tributary to the Charles River (Mine Brook). The strength of the R2Cross and Wetted-Perimeter methods is that they may be applied at ungaged locations whereas the Tennant method and the Range of Variability Approach require a period of streamflow record for analysis. Fish community assessments conducted at or near riffle sites in flowing reaches of the Assabet River and Charles River Basins were used to indicate ecological conditions. The fish communities in the main stem and tributary reaches of both the Assabet and Charles River Basins indicated degraded aquatic ecosystems. However, the degree of degradation differs between the two basins. The extreme predominance of tolerant, generalist species in the Charles River fish community demon-strates the cumulative impacts of flow, habitat, and water-chemistry degradation, combined with the effects of nearby impoundments and changing land use. The range of discharges for nine ungaged riffle reaches defined by the median R2Cross 3-of-3 criteria, R2Cross 2-of-3 criteria, and Wetted-Perimeter streamflow requirements, was 0.86 cubic foot per second per square mile, 0.18 cubic foot per second per square mile, and 0.23 cubic foot per second per square mile, respectively. Application of R2Cross and Wetted-Perimeter methods to sites with altered streamflows or at sites that are riffles only at low to moderate flows can result in a greater variability of
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NASA Technical Reports Server (NTRS)
Kennedy, Kriss J.
2009-01-01
The Surface Habitat Systems (SHS) Focused Investment Group (FIG) is part of the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) effort to provide a focused direction and funding to the various projects that are working on human surface habitat designs and technologies for the planetary exploration missions. The overall SHS-FIG effort focuses on directing and guiding those projects that: 1) develop and demonstrate new surface habitat system concepts, innovations, and technologies to support human exploration missions, 2) improve environmental systems that interact with human habitats, 3) handle and emplace human surface habitats, and 4) focus on supporting humans living and working in habitats on planetary surfaces. The activity areas of the SHS FIG described herein are focused on the surface habitat project near-term objectives as described in this document. The SHS-FIG effort focuses on mitigating surface habitat risks (as identified by the Lunar Surface Systems Project Office (LSSPO) Surface Habitat Element Team; and concentrates on developing surface habitat technologies as identified in the FY08 gap analysis. The surface habitat gap assessment will be updated annually as the surface architecture and surface habitat definition continues to mature. These technologies are mapped to the SHS-FIG Strategic Development Roadmap. The Roadmap will bring to light the areas where additional innovative efforts are needed to support the development of habitat concepts and designs and the development of new technologies to support of the LSSPO Habitation Element development plan. Three specific areas of development that address Lunar Architecture Team (LAT)-2 and Constellation Architecture Team (CxAT) Lunar habitat design issues or risks will be focused on by the SHS-FIG. The SHS-FIG will establish four areas of development that will help the projects prepare in their planning for surface habitat systems development. Those development areas are
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Krstolic, Jennifer L.; Hayes, Donald C.; Ruhl, Peter M.
2006-01-01
Increasing development and increasing water withdrawals for public, industrial, and agricultural water supply threaten to reduce streamflows in the Shenandoah River basin in Virginia. Water managers need more information to balance human water-supply needs with the daily streamflows necessary for maintaining the aquatic ecosystems. To meet the need for comprehensive information on hydrology, water supply, and instream-flow requirements of the Shenandoah River basin, the U.S. Geological Survey and the Northern Shenandoah Valley Regional Commission conducted a cooperative investigation of habitat availability during low-flow periods on the North Fork Shenandoah River. Historic streamflow data and empirical data on physical habitat, river hydraulics, fish community structure, and recreation were used to develop a physical habitat simulation model. Hydraulic measurements were made during low, medium, and high flows in six reaches at a total of 36 transects that included riffles, runs, and pools, and that had a variety of substrates and cover types. Habitat suitability criteria for fish were developed from detailed fish-community sampling and microhabitat observations. Fish were grouped into four guilds of species and life stages with similar habitat requirements. Simulated habitat was considered in the context of seasonal flow regimes to show the availability of flows that sustain suitable habitat during months when precipitation and streamflow are scarce. The North Fork Shenandoah River basin was divided into three management sections for analysis purposes: the upper section, middle section, and lower section. The months of July, August, and September were chosen to represent a low-flow period in the basin with low mean monthly flows, low precipitation, high temperatures, and high water withdrawals. Exceedance flows calculated from the combined data from these three months describe low-flow periods on the North Fork Shenandoah River. Long-term records from three
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Global patterns of fragmentation and connectivity of mammalian carnivore habitat.
Crooks, Kevin R; Burdett, Christopher L; Theobald, David M; Rondinini, Carlo; Boitani, Luigi
2011-09-27
Although mammalian carnivores are vulnerable to habitat fragmentation and require landscape connectivity, their global patterns of fragmentation and connectivity have not been examined. We use recently developed high-resolution habitat suitability models to conduct comparative analyses and to identify global hotspots of fragmentation and connectivity for the world's terrestrial carnivores. Species with less fragmentation (i.e. more interior high-quality habitat) had larger geographical ranges, a greater proportion of habitat within their range, greater habitat connectivity and a lower risk of extinction. Species with higher connectivity (i.e. less habitat isolation) also had a greater proportion of high-quality habitat, but had smaller, not larger, ranges, probably reflecting shorter distances between habitat patches for species with restricted distributions; such species were also more threatened, as would be expected given the negative relationship between range size and extinction risk. Fragmentation and connectivity did not differ among Carnivora families, and body mass was associated with connectivity but not fragmentation. On average, only 54.3 per cent of a species' geographical range comprised high-quality habitat, and more troubling, only 5.2 per cent of the range comprised such habitat within protected areas. Identification of global hotspots of fragmentation and connectivity will help guide strategic priorities for carnivore conservation.
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Global patterns of fragmentation and connectivity of mammalian carnivore habitat
Crooks, Kevin R.; Burdett, Christopher L.; Theobald, David M.; Rondinini, Carlo; Boitani, Luigi
2011-01-01
Although mammalian carnivores are vulnerable to habitat fragmentation and require landscape connectivity, their global patterns of fragmentation and connectivity have not been examined. We use recently developed high-resolution habitat suitability models to conduct comparative analyses and to identify global hotspots of fragmentation and connectivity for the world's terrestrial carnivores. Species with less fragmentation (i.e. more interior high-quality habitat) had larger geographical ranges, a greater proportion of habitat within their range, greater habitat connectivity and a lower risk of extinction. Species with higher connectivity (i.e. less habitat isolation) also had a greater proportion of high-quality habitat, but had smaller, not larger, ranges, probably reflecting shorter distances between habitat patches for species with restricted distributions; such species were also more threatened, as would be expected given the negative relationship between range size and extinction risk. Fragmentation and connectivity did not differ among Carnivora families, and body mass was associated with connectivity but not fragmentation. On average, only 54.3 per cent of a species' geographical range comprised high-quality habitat, and more troubling, only 5.2 per cent of the range comprised such habitat within protected areas. Identification of global hotspots of fragmentation and connectivity will help guide strategic priorities for carnivore conservation. PMID:21844043
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Centeno-Cuadros, Alejandro; Román, Jacinto; Delibes, Miguel; Godoy, José Antonio
2011-01-01
Habitat specialists inhabiting scarce and scattered habitat patches pose interesting questions related to dispersal such as how specialized terrestrial mammals do to colonize distant patches crossing hostile matrices. We assess dispersal patterns of the southern water vole (Arvicola sapidus), a habitat specialist whose habitat patches are distributed through less than 2% of the study area (overall 600 km2) and whose populations form a dynamic metapopulational network. We predict that individuals will require a high ability to move through the inhospitable matrix in order to avoid genetic and demographic isolations. Genotypes (N = 142) for 10 microsatellites and sequences of the whole mitochondrial Control Region (N = 47) from seven localities revealed a weak but significant genetic structure partially explained by geographic distance. None of the landscape models had a significant effect on genetic structure over that of the Euclidean distance alone and no evidence for efficient barriers to dispersal was found. Contemporary gene flow was not severely limited for A. sapidus as shown by high migration rates estimates (>10%) between non-neighbouring areas. Sex-biased dispersal tests did not support differences in dispersal rates, as shown by similar average axial parent-offspring distances, in close agreement with capture-mark-recapture estimates. As predicted, our results do not support any preferences of the species for specific landscape attributes on their dispersal pathways. Here, we combine field and molecular data to illustrate how a habitat specialist mammal might disperse like a habitat generalist, acquiring specific long-distance dispersal strategies as an adaptation to patchy, naturally fragmented, heterogeneous and unstable habitats. PMID:21931775
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NASA Astrophysics Data System (ADS)
Benito, Xavier; Trobajo, Rosa; Cearreta, Alejandro; Ibáñez, Carles
2016-10-01
The ecology and modern distribution of benthic foraminiferal assemblages were analysed in the Ebro Delta (NW Mediterranean Sea). Foraminiferal distributions were from 191 sediment surface samples covering a wide range of deltaic habitats and adjacent open sea areas. According to similarity in species composition, cluster analysis identified four habitat types: (1) offshore habitat, (2) nearshore and outer bays, (3) salt and brackish marshes and (4) coastal lagoons and inner bays. Canonical Correspondence Analysis identified water depth, salinity and sand content as the main environmental factors structuring living foraminiferal assemblages. Partial Canonical Correspondence Analysis revealed water depth as the most statistically significant associated with the distribution of modern foraminifera in the Ebro Delta. Thus, a transfer function for water depth using Weighted Average Partial Least Squares regression was successfully developed. Although depth per se is unlikely to affect the foraminifera directly but will exert its effects via various environmental variables that co-vary with depth in the deltaic habitats (e.g. hydrodynamics, oxygen, food availability, etc), the resulting model (r2 = 0.89; RMSEP = 0.32 log10 m) suggested a strong correlation between observed and foraminifera-predicted water depths, and therefore provided a potentially useful tool for water-depth reconstructions in the Ebro Delta. This work indicated the potential role of modern foraminifera as quantitative indicators of water depth and habitat types in the Ebro Delta. This complementary approach (transfer function and indicator species) will allow reconstruction of the palaeoenvironmental changes that have occurred in the Ebro Delta based on the benthic foraminiferal record.
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NASA Astrophysics Data System (ADS)
Nijland, W.; Coops, N. C.; Nielsen, S. E.; Stenhouse, G.
2015-06-01
Wildlife habitat selection is determined by a wide range of factors including food availability, shelter, security and landscape heterogeneity all of which are closely related to the more readily mapped landcover types and disturbance regimes. Regional wildlife habitat studies often used moderate resolution multispectral satellite imagery for wall to wall mapping, because it offers a favourable mix of availability, cost and resolution. However, certain habitat characteristics such as canopy structure and topographic factors are not well discriminated with these passive, optical datasets. Airborne laser scanning (ALS) provides highly accurate three dimensional data on canopy structure and the underlying terrain, thereby offers significant enhancements to wildlife habitat mapping. In this paper, we introduce an approach to integrate ALS data and multispectral images to develop a new heuristic wildlife habitat classifier for western Alberta. Our method combines ALS direct measures of canopy height, and cover with optical estimates of species (conifer vs. deciduous) composition into a decision tree classifier for habitat - or landcover types. We believe this new approach is highly versatile and transferable, because class rules can be easily adapted for other species or functional groups. We discuss the implications of increased ALS availability for habitat mapping and wildlife management and provide recommendations for integrating multispectral and ALS data into wildlife management.
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Habitat use by larval fishes in a temperate South African surf zone
NASA Astrophysics Data System (ADS)
Watt-Pringle, Peter; Strydom, Nadine A.
2003-12-01
Larval fishes were sampled in the Kwaaihoek surf zone on the south east coast of South Africa. On six occasions between February and May 2002, larval fishes were collected in two habitat types identified in the inner surf zone using a modified beach-seine net. The surf zone habitats were classified as either sheltered trough areas or adjacent exposed surf areas. Temperature, depth and current measurements were taken at all sites. Trough habitats consisted of a depression in surf topography characterised by reduced current velocities and greater average depth than adjacent surf areas. In total, 325 larval fishes were collected. Of these, 229 were collected in trough and 96 in surf habitats. At least 22 families and 37 species were represented in the catch. Dominant families were the Mugilidae, Sparidae, Atherinidae, and Engraulidae. Dominant species included Liza tricuspidens and Liza richardsonii (Mugilidae), Rhabdosargus holubi and Sarpa salpa (Sparidae), Atherina breviceps (Atherinidae) and Engraulis japonicus (Engraulide). Mean CPUE of postflexion larvae of estuary-dependent species was significantly greater in trough areas. The proportion of postflexion larval fishes in trough habitat was significantly greater than that of preflexion stages, a result that was not apparent in surf habitat sampled. CPUE of postflexion larvae of estuary-dependent fishes was negatively correlated with current magnitude and positively correlated with habitat depth. Mean body length of larval fishes was significantly greater in trough than in surf habitats. These results provide evidence that the CPUE of postflexion larvae of estuary-dependent fishes is higher in trough habitat in the surf zone and this may be indicative of active habitat selection for areas of reduced current velocity/wave action. The implications of this behaviour for estuarine recruitment processes are discussed.
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Vanderpham, J P; Nakagawa, S; Senior, A M; Closs, G P
2016-04-01
An investigation of intraspecific habitat-related patterns of variation in oculoscapular lateral-line superficial neuromasts (SN) identified a decrease in the ratio of total SNs to pores, and a trend towards decreased asymmetry in SNs in the habitat-generalist common bully Gobiomorphus cotidianus from fluvial habitats compared to lacustrine habitats, suggesting habitat-related phenotypic variability. A greater ratio of pores to SNs, as well as less variation in the total number and asymmetry of SNs observed in the fluvial habitat-specialist redfin bully Gobiomorphus huttoni may provide further evidence of variations in the oculoscapular lateral-line morphology of fluvial habitat G. cotidianus individuals serving as adaptations to more turbulent environments. © 2016 The Fisheries Society of the British Isles.
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Zhou, Xi-Yin; Lei, Kun; Meng, Wei
2017-09-01
Coastal zones are population and economy highly intensity regions all over the world, and coastal habitat supports the sustainable development of human society. The accurate assessment of coastal habitat degradation is the essential prerequisite for coastal zone protection. In this study, an integrated framework of coastal habitat degradation assessment including landuse classification, habitat classifying and zoning, evaluation criterion of coastal habitat degradation and coastal habitat degradation index has been established for better regional coastal habitat assessment. Through establishment of detailed three-class landuse classification, the fine landscape change is revealed, the evaluation criterion of coastal habitat degradation through internal comparison based on the results of habitat classifying and zoning could indicate the levels of habitat degradation and distinguish the intensity of human disturbances in different habitat subareas under the same habitat classification. Finally, the results of coastal habitat degradation assessment could be achieved through coastal habitat degradation index (CHI). A case study of the framework is carried out in the Circum-Bohai-Sea-Coast, China, and the main results show the following: (1) The accuracy of all land use classes are above 90%, which indicates a satisfactory accuracy for the classification map. (2) The Circum-Bohai-Sea-Coast is divided into 3 kinds of habitats and 5 subareas. (3) In the five subareas of the Circum-Bohai-Sea-Coast, the levels of coastal habitat degradation own significant difference. The whole Circum-Bohai-Sea-Coast generally is in a worse state according to area weighting of each habitat subarea. This assessment framework of coastal habitat degradation would characterize the landuse change trend, realize better coastal habitat degradation assessment, reveal the habitat conservation tendency and distinguish intensity of human disturbances. Furthermore, it would support for accurate coastal
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Deep Space Habitat Wireless Smart Plug
NASA Technical Reports Server (NTRS)
Morgan, Joseph A.; Porter, Jay; Rojdev, Kristina; Carrejo, Daniel B.; Colozza, Anthony J.
2014-01-01
NASA has been interested in technology development for deep space exploration, and one avenue of developing these technologies is via the eXploration Habitat (X-Hab) Academic Innovation Challenge. In 2013, NASA's Deep Space Habitat (DSH) project was in need of sensors that could monitor the power consumption of various devices in the habitat with added capability to control the power to these devices for load shedding in emergency situations. Texas A&M University's Electronic Systems Engineering Technology Program (ESET) in conjunction with their Mobile Integrated Solutions Laboratory (MISL) accepted this challenge, and over the course of 2013, several undergraduate students in a Capstone design course developed five wireless DC Smart Plugs for NASA. The wireless DC Smart Plugs developed by Texas A&M in conjunction with NASA's Deep Space Habitat team is a first step in developing wireless instrumentation for future flight hardware. This paper will further discuss the X-Hab challenge and requirements set out by NASA, the detailed design and testing performed by Texas A&M, challenges faced by the team and lessons learned, and potential future work on this design.
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Habitat Concepts for Deep Space Exploration
NASA Technical Reports Server (NTRS)
Smitherman, David; Griffin, Brand N.
2014-01-01
Future missions under consideration requiring human habitation beyond the International Space Station (ISS) include deep space habitats in the lunar vicinity to support asteroid retrieval missions, human and robotic lunar missions, satellite servicing, and Mars vehicle servicing missions. Habitat designs are also under consideration for missions beyond the Earth-Moon system, including transfers to near-Earth asteroids and Mars orbital destinations. A variety of habitat layouts have been considered, including those derived from the existing ISS designs and those that could be fabricated from the Space Launch System (SLS) propellant tanks. This paper presents a comparison showing several options for asteroid, lunar, and Mars mission habitats using ISS derived and SLS derived modules and identifies some of the advantages and disadvantages inherent in each. Key findings indicate that the larger SLS diameter modules offer built-in compatibility with the launch vehicle, single launch capability without on-orbit assembly, improved radiation protection, lighter structures per unit volume, and sufficient volume to accommodate consumables for long duration missions without resupply. The information provided with the findings includes mass and volume comparison data that should be helpful to future exploration mission planning efforts.
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Transferability of habitat suitability models for nesting woodpeckers associated with wildfire
Quresh S. Latif; Vicki Saab; Jeff P. Hollenbeck; Jonathan G. Dudley
2016-01-01
Following wildfire, forest managers are challenged with meeting both socioeconomic demands (e.g., salvage logging) and mandates requiring habitat conservation for disturbance-associated wildlife (e.g., woodpeckers). Habitat suitability models for nesting woodpeckers can be informative, but tests of model transferability are needed to understand how broadly...
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Understanding Existing Salmonid Habitat Availability and Connectivity to Improve River Management
NASA Astrophysics Data System (ADS)
Duffin, J.; Yager, E.; Tonina, D.; Benjankar, R. M.
2017-12-01
In the Pacific Northwest river restoration is common for salmon conservation. Mangers need methods to help target restoration to problem areas in rivers to create habitat that meets a species' needs. Hydraulic models and habitat suitability curves provide basic information on habitat availability and overall quality, but these analyses need to be expanded to address habitat quality based on the accessibility of habitats required for multiple life stages. Scientists are starting to use connectivity measurements to understand the longitudinal proximity of habitat patches, which can be used to address the habitat variability of a reach. By evaluating the availability and quality of habitat and calculating the connectivity between complementary habitats, such as spawning and rearing habitats, we aim to identify areas that should be targeted for restoration. To meet these goals, we assessed Chinook salmon habitat on the Lemhi River in Idaho. The depth and velocity outputs from a 2D hydraulic model are used in conjunction with locally created habitat suitability curves to evaluate the availability and quality of habitat for multiple Chinook salmon life stages. To assess the variability of the habitat, connectivity between habitat patches necessary for different life stages is calculated with a proximity index. A spatial representation of existing habitat quality and connectivity between complimentary habitats can be linked to river morphology by the evaluation of local geomorphic characteristics, including sinuosity and channel units. The understanding of the current habitat availability for multiple life stage needs, the connectivity between these habitat patches, and their relationship with channel morphology can help managers better identify restoration needs and direct their limited resources.
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Definition and Development of Habitation Readiness Levels (HRLs) for Planetary Surface Habitats
NASA Technical Reports Server (NTRS)
Connolly, Janis H.; Toups, Larry
2007-01-01
One could argue that NASA has never developed a true habitat for a planetary surface, with only the Lunar Module from the 1960's-era Apollo Program providing for a sparse 2 person, 3 day capability. An integral part of NASA's current National Vision for Space Exploration is missions back to the moon and eventually to Mars. One of the largest leaps i11 lunar surface exploration beyond the Apollo lunar missions will be the conduct of these extended duration human missions. These missions could range from 30 to 90 days in length initially and may eventually range up to 500 days in length. To enable these extended duration human missions, probably the single-most important lunar surface element is the Surface Habitat. The requirements that must be met by the Surface Habitat will go far beyond the safety, performance and operational requirements of the Lunar Module, and NASA needs to develop a basis for making intelligent, technically correct habitat design decisions. This paper will discuss the possibilities of the definition and development of a Habitation Readiness Level (HRL) scale that might be mapped to current Technology Readiness Levels (TRLs) for technology development. HRLs could help measure how well a particular technology thrust is advanced by a proposed planetary habitat concept. The readiness level would have to be measured differently than TRLs, and may include such milestones as habitat design performance under simulated mission operations and constraints (including relevant field testing), functional allocation demonstrations, crew interface evaluation and post-occupancy evaluation. With many concepts for planetary habitats proposed over the past 20 years, there are many strategic technical challenges facing designers of planetary habitats that will support NASA's exploration of the moon and Mars. The systematic assessment of a variety of planetary habitat options will be an important approach and will influence the associated requirements for human
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7 CFR 636.4 - Program requirements.
Code of Federal Regulations, 2013 CFR
2013-01-01
... AGRICULTURE LONG TERM CONTRACTING WILDLIFE HABITAT INCENTIVE PROGRAM § 636.4 Program requirements. (a) To... for the development of fish and wildlife habitat as described in § 636.9; (5) Provide NRCS with... in a program where fish and wildlife habitat objectives have been sufficiently achieved, as...
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7 CFR 636.4 - Program requirements.
Code of Federal Regulations, 2014 CFR
2014-01-01
... AGRICULTURE LONG TERM CONTRACTING WILDLIFE HABITAT INCENTIVE PROGRAM § 636.4 Program requirements. (a) To... for the development of fish and wildlife habitat as described in § 636.9; (5) Provide NRCS with... in a program where fish and wildlife habitat objectives have been sufficiently achieved, as...
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7 CFR 636.4 - Program requirements.
Code of Federal Regulations, 2011 CFR
2011-01-01
... AGRICULTURE LONG TERM CONTRACTING WILDLIFE HABITAT INCENTIVE PROGRAM § 636.4 Program requirements. (a) To... for the development of fish and wildlife habitat as described in § 636.9; (5) Provide NRCS with... in a program where fish and wildlife habitat objectives have been sufficiently achieved, as...
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7 CFR 636.4 - Program requirements.
Code of Federal Regulations, 2012 CFR
2012-01-01
... AGRICULTURE LONG TERM CONTRACTING WILDLIFE HABITAT INCENTIVE PROGRAM § 636.4 Program requirements. (a) To... for the development of fish and wildlife habitat as described in § 636.9; (5) Provide NRCS with... in a program where fish and wildlife habitat objectives have been sufficiently achieved, as...
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Fitzpatrick, Faith A.; Peppler, Marie C.; Saad, David A.; Pratt, Dennis M.; Lenz, Bernard N.
2015-01-01
Available brook-trout habitat is dependent on the locations of groundwater upwellings, the sizes of flood peaks, and sediment loads. Management practices that focus on reducing or slowing runoff from upland areas and increasing channel roughness have potential to reduce flood peaks, erosion, and sedimentation and improve brook-trout habitat in all Bayfield Peninsula streams.
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Global screening for Critical Habitat in the terrestrial realm
Blyth, Simon; Bennun, Leon; Butchart, Stuart H. M.; Hoffmann, Michael; Burgess, Neil D.; Cuttelod, Annabelle; Jones, Matt I.; Kapos, Val; Pilgrim, John; Tolley, Melissa J.; Underwood, Emma C.; Weatherdon, Lauren V.
2018-01-01
Critical Habitat has become an increasingly important concept used by the finance sector and businesses to identify areas of high biodiversity value. The International Finance Corporation (IFC) defines Critical Habitat in their highly influential Performance Standard 6 (PS6), requiring projects in Critical Habitat to achieve a net gain of biodiversity. Here we present a global screening layer of Critical Habitat in the terrestrial realm, derived from global spatial datasets covering the distributions of 12 biodiversity features aligned with guidance provided by the IFC. Each biodiversity feature is categorised as ‘likely’ or ‘potential’ Critical Habitat based on: 1. Alignment between the biodiversity feature and the IFC Critical Habitat definition; and 2. Suitability of the spatial resolution for indicating a feature’s presence on the ground. Following the initial screening process, Critical Habitat must then be assessed in-situ by a qualified assessor. This analysis indicates that a total of 10% and 5% of the global terrestrial environment can be considered as likely and potential Critical Habitat, respectively, while the remaining 85% did not overlap with any of the biodiversity features assessed and was classified as ‘unknown’. Likely Critical Habitat was determined principally by the occurrence of Key Biodiversity Areas and Protected Areas. Potential Critical Habitat was predominantly characterised by data representing highly threatened and unique ecosystems such as ever-wet tropical forests and tropical dry forests. The areas we identified as likely or potential Critical Habitat are based on the best available global-scale data for the terrestrial realm that is aligned with IFC’s Critical Habitat definition. Our results can help businesses screen potential development sites at the early project stage based on a range of biodiversity features. However, the study also demonstrates several important data gaps and highlights the need to incorporate
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Global screening for Critical Habitat in the terrestrial realm.
Brauneder, Kerstin M; Montes, Chloe; Blyth, Simon; Bennun, Leon; Butchart, Stuart H M; Hoffmann, Michael; Burgess, Neil D; Cuttelod, Annabelle; Jones, Matt I; Kapos, Val; Pilgrim, John; Tolley, Melissa J; Underwood, Emma C; Weatherdon, Lauren V; Brooks, Sharon E
2018-01-01
Critical Habitat has become an increasingly important concept used by the finance sector and businesses to identify areas of high biodiversity value. The International Finance Corporation (IFC) defines Critical Habitat in their highly influential Performance Standard 6 (PS6), requiring projects in Critical Habitat to achieve a net gain of biodiversity. Here we present a global screening layer of Critical Habitat in the terrestrial realm, derived from global spatial datasets covering the distributions of 12 biodiversity features aligned with guidance provided by the IFC. Each biodiversity feature is categorised as 'likely' or 'potential' Critical Habitat based on: 1. Alignment between the biodiversity feature and the IFC Critical Habitat definition; and 2. Suitability of the spatial resolution for indicating a feature's presence on the ground. Following the initial screening process, Critical Habitat must then be assessed in-situ by a qualified assessor. This analysis indicates that a total of 10% and 5% of the global terrestrial environment can be considered as likely and potential Critical Habitat, respectively, while the remaining 85% did not overlap with any of the biodiversity features assessed and was classified as 'unknown'. Likely Critical Habitat was determined principally by the occurrence of Key Biodiversity Areas and Protected Areas. Potential Critical Habitat was predominantly characterised by data representing highly threatened and unique ecosystems such as ever-wet tropical forests and tropical dry forests. The areas we identified as likely or potential Critical Habitat are based on the best available global-scale data for the terrestrial realm that is aligned with IFC's Critical Habitat definition. Our results can help businesses screen potential development sites at the early project stage based on a range of biodiversity features. However, the study also demonstrates several important data gaps and highlights the need to incorporate new and
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A Testbed for Evaluating Lunar Habitat Autonomy Architectures
NASA Technical Reports Server (NTRS)
Lawler, Dennis G.
2008-01-01
A lunar outpost will involve a habitat with an integrated set of hardware and software that will maintain a safe environment for human activities. There is a desire for a paradigm shift whereby crew will be the primary mission operators, not ground controllers. There will also be significant periods when the outpost is uncrewed. This will require that significant automation software be resident in the habitat to maintain all system functions and respond to faults. JSC is developing a testbed to allow for early testing and evaluation of different autonomy architectures. This will allow evaluation of different software configurations in order to: 1) understand different operational concepts; 2) assess the impact of failures and perturbations on the system; and 3) mitigate software and hardware integration risks. The testbed will provide an environment in which habitat hardware simulations can interact with autonomous control software. Faults can be injected into the simulations and different mission scenarios can be scripted. The testbed allows for logging, replaying and re-initializing mission scenarios. An initial testbed configuration has been developed by combining an existing life support simulation and an existing simulation of the space station power distribution system. Results from this initial configuration will be presented along with suggested requirements and designs for the incremental development of a more sophisticated lunar habitat testbed.
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Predicting minimum habitat characteristics for the Indiana bat in the Champlain Valley
Watrous, K.S.; Donovan, T.M.; Mickey, R.M.; Darling, S.R.; Hicks, A.C.; Von Oettingen, S. L.
2006-01-01
Predicting potential habitat across a landscape for rare species is extremely challenging. However, partitioned Mahalanobis D2 methods avoid pitfalls commonly encountered when surveying rare species by using data collected only at known species locations. Minimum habitat requirements are then determined by examining a principal components analysis to find consistent habitat characteristics across known locations. We used partitioned D 2 methods to examine minimum habitat requirements of Indiana bats (Myotis sodalis) in the Champlain Valley of Vermont and New York, USA, across 7 spatial scales and map potential habitat for the species throughout the same area. We radiotracked 24 female Indiana bats to their roost trees and across their nighttime foraging areas to collect habitat characteristics at 7 spatial scales: 1) roost trees, 2) 0.1-ha circular plots surrounding the roost trees, 3) home ranges, and 4-7) 0.5-km, 1-km, 2-km, and 3-km buffers surrounding the roost tree. Roost trees (n = 50) typically were tall, dead, large-diameter trees with exfoliating bark, located at low elevations and close to water. Trees surrounding roosts typically were smaller in diameter and shorter in height, but they had greater soundness than the roost trees. We documented 14 home ranges in areas of diverse, patchy land cover types that were close to water with east-facing aspects. Across all landscape extents, area of forest within roost-tree buffers and the aspect across those buffers were the most consistent features. Predictive maps indicated that suitable habitat ranged from 4.7-8.1% of the area examined within the Champlain Valley. These habitat models further understanding of Indiana bat summer habitat by indicating minimum habitat characteristics at multiple scales and can be used to aid management decisions by highlighting potential habitat. Nonetheless, information on juvenile production and recruitment is lacking; therefore, assessments of Indiana bat habitat quality in the
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A Bayesian method for assessing multiscalespecies-habitat relationships
Stuber, Erica F.; Gruber, Lutz F.; Fontaine, Joseph J.
2017-01-01
ContextScientists face several theoretical and methodological challenges in appropriately describing fundamental wildlife-habitat relationships in models. The spatial scales of habitat relationships are often unknown, and are expected to follow a multi-scale hierarchy. Typical frequentist or information theoretic approaches often suffer under collinearity in multi-scale studies, fail to converge when models are complex or represent an intractable computational burden when candidate model sets are large.ObjectivesOur objective was to implement an automated, Bayesian method for inference on the spatial scales of habitat variables that best predict animal abundance.MethodsWe introduce Bayesian latent indicator scale selection (BLISS), a Bayesian method to select spatial scales of predictors using latent scale indicator variables that are estimated with reversible-jump Markov chain Monte Carlo sampling. BLISS does not suffer from collinearity, and substantially reduces computation time of studies. We present a simulation study to validate our method and apply our method to a case-study of land cover predictors for ring-necked pheasant (Phasianus colchicus) abundance in Nebraska, USA.ResultsOur method returns accurate descriptions of the explanatory power of multiple spatial scales, and unbiased and precise parameter estimates under commonly encountered data limitations including spatial scale autocorrelation, effect size, and sample size. BLISS outperforms commonly used model selection methods including stepwise and AIC, and reduces runtime by 90%.ConclusionsGiven the pervasiveness of scale-dependency in ecology, and the implications of mismatches between the scales of analyses and ecological processes, identifying the spatial scales over which species are integrating habitat information is an important step in understanding species-habitat relationships. BLISS is a widely applicable method for identifying important spatial scales, propagating scale uncertainty, and
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Vita Wright; Sallie J. Hejl; Richard L. Hutto
1997-01-01
Our multi-scale analysis of Flammulated Owl (Otus flammeolus) habitat use in the northern Rocky Mountains indicates some landscapes may be unsuitable for this species. As a result, there may be less habitat available for Flammulated Owls than thought based on the results of microhabitat studies. Thus, we suggest Flammulated Owl habitat conservation...
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Ecosystem services Linking People to Coastal Habitats.
Given the growing desire to incorporate ecosystem goods and services (EGS) considerations into coastal planning efforts, it is imperative that stakeholders understand how coastal habitats affect the availability and delivery of those EGS. Nonetheless, methods requiring long-term ...
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Using urban forest assessment tools to model bird habitat potential
Lerman, Susannah B.; Nislow, Keith H.; Nowak, David J.; DeStefano, Stephen; King, David I.; Jones-Farrand, D. Todd
2014-01-01
The alteration of forest cover and the replacement of native vegetation with buildings, roads, exotic vegetation, and other urban features pose one of the greatest threats to global biodiversity. As more land becomes slated for urban development, identifying effective urban forest wildlife management tools becomes paramount to ensure the urban forest provides habitat to sustain bird and other wildlife populations. The primary goal of this study was to integrate wildlife suitability indices to an existing national urban forest assessment tool, i-Tree. We quantified available habitat characteristics of urban forests for ten northeastern U.S. cities, and summarized bird habitat relationships from the literature in terms of variables that were represented in the i-Tree datasets. With these data, we generated habitat suitability equations for nine bird species representing a range of life history traits and conservation status that predicts the habitat suitability based on i-Tree data. We applied these equations to the urban forest datasets to calculate the overall habitat suitability for each city and the habitat suitability for different types of land-use (e.g., residential, commercial, parkland) for each bird species. The proposed habitat models will help guide wildlife managers, urban planners, and landscape designers who require specific information such as desirable habitat conditions within an urban management project to help improve the suitability of urban forests for birds.
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A comparison of two modeling approaches for evaluating wildlife--habitat relationships
Ryan A. Long; Jonathan D. Muir; Janet L. Rachlow; John G. Kie
2009-01-01
Studies of resource selection form the basis for much of our understanding of wildlife habitat requirements, and resource selection functions (RSFs), which predict relative probability of use, have been proposed as a unifying concept for analysis and interpretation of wildlife habitat data. Logistic regression that contrasts used and available or unused resource units...
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Camouflage and individual variation in shore crabs (Carcinus maenas) from different habitats.
Stevens, Martin; Lown, Alice E; Wood, Louisa E
2014-01-01
Camouflage is widespread throughout the natural world and conceals animals from predators in a vast range of habitats. Because successful camouflage usually involves matching aspects of the background environment, species and populations should evolve appearances tuned to their local habitat, termed phenotype-environment associations. However, although this has been studied in various species, little work has objectively quantified the appearances of camouflaged animals from different habitats, or related this to factors such as ontogeny and individual variation. Here, we tested for phenotype-environment associations in the common shore crab (Carcinus maenas), a species highly variable in appearance and found in a wide range of habitats. We used field surveys and digital image analysis of the colors and patterns of crabs found in four locations around Cornwall in the UK to quantify how individuals vary with habitat (predominantly rockpool, mussel bed, and mudflat). We find that individuals from sites comprising different backgrounds show substantial differences in several aspects of color and pattern, and that this is also dependent on life stage (adult or juvenile). Furthermore, the level of individual variation is dependent on site and life stage, with juvenile crabs often more variable than adults, and individuals from more homogenous habitats less diverse. Ours is the most comprehensive study to date exploring phenotype-environment associations for camouflage and individual variation in a species, and we discuss the implications of our results in terms of the mechanisms and selection pressures that may drive this.
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Camouflage and Individual Variation in Shore Crabs (Carcinus maenas) from Different Habitats
Stevens, Martin; Lown, Alice E.; Wood, Louisa E.
2014-01-01
Camouflage is widespread throughout the natural world and conceals animals from predators in a vast range of habitats. Because successful camouflage usually involves matching aspects of the background environment, species and populations should evolve appearances tuned to their local habitat, termed phenotype-environment associations. However, although this has been studied in various species, little work has objectively quantified the appearances of camouflaged animals from different habitats, or related this to factors such as ontogeny and individual variation. Here, we tested for phenotype-environment associations in the common shore crab (Carcinus maenas), a species highly variable in appearance and found in a wide range of habitats. We used field surveys and digital image analysis of the colors and patterns of crabs found in four locations around Cornwall in the UK to quantify how individuals vary with habitat (predominantly rockpool, mussel bed, and mudflat). We find that individuals from sites comprising different backgrounds show substantial differences in several aspects of color and pattern, and that this is also dependent on life stage (adult or juvenile). Furthermore, the level of individual variation is dependent on site and life stage, with juvenile crabs often more variable than adults, and individuals from more homogenous habitats less diverse. Ours is the most comprehensive study to date exploring phenotype-environment associations for camouflage and individual variation in a species, and we discuss the implications of our results in terms of the mechanisms and selection pressures that may drive this. PMID:25551233
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A geospatial modelling approach to predict seagrass habitat recovery under multiple stressor regimes
Restoration of estuarine seagrass habitats requires a clear understanding of the modes of action of multiple interacting stressors including nutrients, climate change, coastal land-use change, and habitat modification. We have developed and demonstrated a geospatial modeling a...
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Indicators: Shallow Water Habitat/In-stream Fish Habitat
Shallow water habitat, also referred to as in-stream fish habitat, refers to areas that fish and other aquatic organisms need for concealment, breeding and feeding. This includes large woody snags, boulders, rock ledges, and undercut banks.
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ERIC Educational Resources Information Center
Naturescope, 1987
1987-01-01
Consists of activities which address the causes of habitat destruction and the effects of habitat loss on animals and plants. Identifies habitat loss as the major reason for the endangerment and extinction of plant and animal species. (ML)
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Tracking changes and preventing loss in critical tiger habitat.
Joshi, Anup R; Dinerstein, Eric; Wikramanayake, Eric; Anderson, Michael L; Olson, David; Jones, Benjamin S; Seidensticker, John; Lumpkin, Susan; Hansen, Matthew C; Sizer, Nigel C; Davis, Crystal L; Palminteri, Suzanne; Hahn, Nathan R
2016-04-01
The global population of wild tigers remains dangerously low at fewer than 3500 individuals. Habitat loss, along with poaching, can undermine the international target recovery of doubling the number of wild tigers by 2022. Using a new satellite-based monitoring system, we analyzed 14 years of forest loss data within the 76 landscapes (ranging from 278 to 269,983 km(2)) that have been prioritized for conservation of wild tigers. Our analysis provides an update of the status of tiger habitat and describes new applications of technology to detect precisely where forest loss is occurring in order to curb future habitat loss. Across the 76 landscapes, forest loss was far less than anticipated (79,597 ± 22,629 km(2), 7.7% of remaining habitat) over the 14-year study period (2001-2014). Habitat loss was unevenly distributed within a subset of 29 landscapes deemed most critical for doubling wild tiger populations: 19 showed little change (1.5%), whereas 10 accounted for more than 98% (57,392 ± 16,316 km(2)) of habitat loss. Habitat loss in source population sites within 76 landscapes ranged from no loss to 435 ± 124 km(2) ([Formula: see text], SD = 89, total = 1676 ± 476 km(2)). Doubling the tiger population by 2022 requires moving beyond tracking annual changes in habitat. We highlight near-real-time forest monitoring technologies that provide alerts of forest loss at relevant spatial and temporal scales to prevent further erosion.
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Electrofishing effort requirements for estimating species richness in the Kootenai River, Idaho
Watkins, Carson J.; Quist, Michael C.; Shepard, Bradley B.; Ireland, Susan C.
2016-01-01
This study was conducted on the Kootenai River, Idaho to provide insight on sampling requirements to optimize future monitoring effort associated with the response of fish assemblages to habitat rehabilitation. Our objective was to define the electrofishing effort (m) needed to have a 95% probability of sampling 50, 75, and 100% of the observed species richness and to evaluate the relative influence of depth, velocity, and instream woody cover on sample size requirements. Sidechannel habitats required more sampling effort to achieve 75 and 100% of the total species richness than main-channel habitats. The sampling effort required to have a 95% probability of sampling 100% of the species richness was 1100 m for main-channel sites and 1400 m for side-channel sites. We hypothesized that the difference in sampling requirements between main- and side-channel habitats was largely due to differences in habitat characteristics and species richness between main- and side-channel habitats. In general, main-channel habitats had lower species richness than side-channel habitats. Habitat characteristics (i.e., depth, current velocity, and woody instream cover) were not related to sample size requirements. Our guidelines will improve sampling efficiency during monitoring effort in the Kootenai River and provide insight on sampling designs for other large western river systems where electrofishing is used to assess fish assemblages.
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Chapter 2. Methods and terminology used with studies of habitat associations
D. Archibald McCallum
1994-01-01
The forest owl conservation assessments emphasize the relationship between flammulated, boreal, and great gray owls and the forests in which they occur. The habitat requirements of the owls and their principal prey bear strongly on the conservation status of the owls. Establishing the characteristics of the owl/habitat relationship is not a trivial or straightforward...
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Forest habitat associations of the golden-mantled ground squirrel: Implications for fuels management
Katharine R. Shick; Dean E. Pearson; Leonard F. Ruggiero
2006-01-01
Golden-mantled ground squirrels are commonly associated with high-elevation habitats near or above upper timberline. This species also occurs in fire-adapted, low-elevation forests that are targeted for forest health restoration (FHR) treatments intended to remove encroaching understory trees and thin overstory trees. Hence, the golden-mantled ground squirrel...
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Habitat classification modeling with incomplete data: Pushing the habitat envelope
Zarnetske, P.L.; Edwards, T.C.; Moisen, Gretchen G.
2007-01-01
Habitat classification models (HCMs) are invaluable tools for species conservation, land-use planning, reserve design, and metapopulation assessments, particularly at broad spatial scales. However, species occurrence data are often lacking and typically limited to presence points at broad scales. This lack of absence data precludes the use of many statistical techniques for HCMs. One option is to generate pseudo-absence points so that the many available statistical modeling tools can be used. Traditional techniques generate pseudoabsence points at random across broadly defined species ranges, often failing to include biological knowledge concerning the species-habitat relationship. We incorporated biological knowledge of the species-habitat relationship into pseudo-absence points by creating habitat envelopes that constrain the region from which points were randomly selected. We define a habitat envelope as an ecological representation of a species, or species feature's (e.g., nest) observed distribution (i.e., realized niche) based on a single attribute, or the spatial intersection of multiple attributes. We created HCMs for Northern Goshawk (Accipiter gentilis atricapillus) nest habitat during the breeding season across Utah forests with extant nest presence points and ecologically based pseudo-absence points using logistic regression. Predictor variables were derived from 30-m USDA Landfire and 250-m Forest Inventory and Analysis (FIA) map products. These habitat-envelope-based models were then compared to null envelope models which use traditional practices for generating pseudo-absences. Models were assessed for fit and predictive capability using metrics such as kappa, thresholdindependent receiver operating characteristic (ROC) plots, adjusted deviance (Dadj2), and cross-validation, and were also assessed for ecological relevance. For all cases, habitat envelope-based models outperformed null envelope models and were more ecologically relevant, suggesting
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Bagavathiannan, Muthukumar V; Gulden, Robert H; Begg, Graham S; Van Acker, Rene C
2010-09-01
Feral populations of cultivated crops can act as reservoirs for novel genetically engineered (GE) traits and aid in trait movement at the landscape level. However, little information is available on the potential of cultivated crops to become feral. In this study, we investigated the ferality of alfalfa populations (non-GE version) occurring in roadside habitats. Knowledge on the nature of roadside alfalfa populations would be useful for designing efficient trait confinement protocols and coexistence strategies in alfalfa. We investigated roadside alfalfa populations from 2006 to 2009 in three rural municipalities (Hanover, MacDonald, and Springfield) in Southern Manitoba, Canada. We studied the demography of these populations including seedbank, seedling recruitment, and fecundity and examined the impact of road verge mowing on key life stages of these populations. We also compared the growth and reproductive attributes of roadside and cultivated alfalfa populations. Alfalfa is reproductively successful in roadside habitats and capable of establishing self-perpetuating populations. A substantial portion of the alfalfa seeds we extracted from seedbank samples were viable but not germinable, suggesting some degree of seedbank persistence in roadside habitats. In the roadside habitat, alfalfa seedlings recruited successfully, however, seedling mortality was high when seedlings were in close proximity to well-established alfalfa plants. Mowing dramatically reduced the reproductive success of roadside alfalfa. Generally, the growth and reproduction of roadside alfalfa was comparable to cultivated alfalfa except for total fecundity. Considering the long lifespan (>10 years) of alfalfa and the levels of fecundity, seedbank, and seedling survival we observed, long-term persistence of roadside alfalfa populations seems reasonable. In the context of novel trait confinement, our results suggest that feral alfalfa populations required to be managed if there is a desire
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Lavery, Paul S.; Mateo, Miguel-Ángel; Serrano, Oscar; Rozaimi, Mohammad
2013-01-01
The recent focus on carbon trading has intensified interest in ‘Blue Carbon’–carbon sequestered by coastal vegetated ecosystems, particularly seagrasses. Most information on seagrass carbon storage is derived from studies of a single species, Posidonia oceanica, from the Mediterranean Sea. We surveyed 17 Australian seagrass habitats to assess the variability in their sedimentary organic carbon (Corg) stocks. The habitats encompassed 10 species, in mono-specific or mixed meadows, depositional to exposed habitats and temperate to tropical habitats. There was an 18-fold difference in the Corg stock (1.09–20.14 mg Corg cm−3 for a temperate Posidonia sinuosa and a temperate, estuarine P. australis meadow, respectively). Integrated over the top 25 cm of sediment, this equated to an areal stock of 262–4833 g Corg m−2. For some species, there was an effect of water depth on the Corg stocks, with greater stocks in deeper sites; no differences were found among sub-tidal and inter-tidal habitats. The estimated carbon storage in Australian seagrass ecosystems, taking into account inter-habitat variability, was 155 Mt. At a 2014–15 fixed carbon price of A$25.40 t−1 and an estimated market price of $35 t−1 in 2020, the Corg stock in the top 25 cm of seagrass habitats has a potential value of $AUD 3.9–5.4 bill. The estimates of annual Corg accumulation by Australian seagrasses ranged from 0.093 to 6.15 Mt, with a most probable estimate of 0.93 Mt y−1 (10.1 t. km−2 y−1). These estimates, while large, were one-third of those that would be calculated if inter-habitat variability in carbon stocks were not taken into account. We conclude that there is an urgent need for more information on the variability in seagrass carbon stock and accumulation rates, and the factors driving this variability, in order to improve global estimates of seagrass Blue Carbon storage. PMID:24040052
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Lavery, Paul S; Mateo, Miguel-Ángel; Serrano, Oscar; Rozaimi, Mohammad
2013-01-01
The recent focus on carbon trading has intensified interest in 'Blue Carbon'-carbon sequestered by coastal vegetated ecosystems, particularly seagrasses. Most information on seagrass carbon storage is derived from studies of a single species, Posidonia oceanica, from the Mediterranean Sea. We surveyed 17 Australian seagrass habitats to assess the variability in their sedimentary organic carbon (C org) stocks. The habitats encompassed 10 species, in mono-specific or mixed meadows, depositional to exposed habitats and temperate to tropical habitats. There was an 18-fold difference in the Corg stock (1.09-20.14 mg C org cm(-3) for a temperate Posidonia sinuosa and a temperate, estuarine P. australis meadow, respectively). Integrated over the top 25 cm of sediment, this equated to an areal stock of 262-4833 g C org m(-2). For some species, there was an effect of water depth on the C org stocks, with greater stocks in deeper sites; no differences were found among sub-tidal and inter-tidal habitats. The estimated carbon storage in Australian seagrass ecosystems, taking into account inter-habitat variability, was 155 Mt. At a 2014-15 fixed carbon price of A$25.40 t(-1) and an estimated market price of $35 t(-1) in 2020, the C org stock in the top 25 cm of seagrass habitats has a potential value of $AUD 3.9-5.4 bill. The estimates of annual C org accumulation by Australian seagrasses ranged from 0.093 to 6.15 Mt, with a most probable estimate of 0.93 Mt y(-1) (10.1 t. km(-2) y(-1)). These estimates, while large, were one-third of those that would be calculated if inter-habitat variability in carbon stocks were not taken into account. We conclude that there is an urgent need for more information on the variability in seagrass carbon stock and accumulation rates, and the factors driving this variability, in order to improve global estimates of seagrass Blue Carbon storage.
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Martin, Barbara A.; Saiki, Michael K.; Fong, Darren
2009-01-01
This study was conducted to better understand the habitat requirements and environmental limiting factors of Syncaris pacifica, the California freshwater shrimp. This federally listed endangered species is native to perennial lowland streams in a few watersheds in northern California. Field sampling occurred in Lagunitas and Olema creeks at seasonal intervals from February 2003 to November 2004. Ten glides, five pools, and five riffles served as fixed sampling reaches, with eight glides, four pools, and four riffles located in Lagunitas Creek and the remainder in Olema Creek. A total of 1773 S. pacifica was counted during this study, all of which were captured along vegetated banks in Lagunitas Creek. Syncaris pacifica was most numerous in glides (64), then in pools (31), and lastly in riffles (5). According to logistic regression analysis, S. pacifica was mostly associated with submerged portions of streambank vegetation (especially overhanging vegetation such as ferns and blackberries, emergent vegetation such as sedge and brooklime, and fine roots associated with water hemlock, willow, sedge, and blackberries) along with low water current velocity and a sandy substrate. These seemingly favorable habitat conditions for S. pacifica were present in glides and pools in Lagunitas Creek, but not in Olema Creek. ?? 2009 The Crustacean Society.
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Estimating value of estuarine habitat to human beneficiaries requires that we understand how habitat alteration impacts function through both production and delivery of ecosystem goods and services (EGS). Here we expand on the habitat valuation technique of Bell (1997) with an es...
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Concurrent assessment of fish and habitat in warmwater streams in Wyoming
Quist, M.C.; Hubert, W.A.; Rahel, F.J.
2006-01-01
Fisheries research and management in North America have focused largely on sport fishes, but native non-game fishes have attracted increased attention due to their declines. The Warmwater Stream Assessment (WSA) was developed to evaluate simultaneously both fish and habitat in Wyoming streams by a process that includes three major components: (1) stream-reach selection and accumulation of existing information, (2) fish and habitat sampling and (3) summarisation and evaluation of fish and habitat information. Fish are sampled by electric fishing or seining and habitat is measured at reach and channel-unit (i.e. pool, run, riffle, side channel, or backwater) scales. Fish and habitat data are subsequently summarised using a data-matrix approach. Hierarchical decision trees are used to assess critical habitat requirements for each fish species expected or found in the reach. Combined measurements of available habitat and the ecology of individual species contribute to the evaluation of the observed fish assemblage. The WSA incorporates knowledge of the fish assemblage and habitat features to enable inferences of factors likely influencing both the fish assemblage and their habitat. The WSA was developed for warmwater streams in Wyoming, but its philosophy, process and conceptual basis may be applied to environmental assessments in other geographical areas. ?? 2006 Blackwell Publishing Ltd.
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Extreme habitats as refuge from parasite infections? Evidence from an extremophile fish
NASA Astrophysics Data System (ADS)
Tobler, Michael; Schlupp, Ingo; García de León, Francisco J.; Glaubrecht, Matthias; Plath, Martin
2007-05-01
Living in extreme habitats typically requires costly adaptations of any organism tolerating these conditions, but very little is known about potential benefits that trade off these costs. We suggest that extreme habitats may function as refuge from parasite infections, since parasites can become locally extinct either directly, through selection by an extreme environmental parameter on free-living parasite stages, or indirectly, through selection on other host species involved in its life cycle. We tested this hypothesis in a small freshwater fish, the Atlantic molly ( Poecilia mexicana) that inhabits normal freshwaters as well as extreme habitats containing high concentrations of toxic hydrogen sulfide. Populations from such extreme habitats are significantly less parasitized by the trematode Uvulifer sp. than a population from a non-sulfidic habitat. We suggest that reduced parasite prevalence may be a benefit of living in sulfidic habitats.
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Biodiversity: Habitat Suitability
Habitat suitability quantifies the relationship between species and habitat, and is evaluated according to the species’ fitness (i.e. proportion of birth rate to death rate). Even though it might maximize evolutionary success, species are not always in habitat that optimizes fit...
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Habitat selection of Rocky Mountain elk in a nonforested environment
Sawyer, H.; Nielson, R.M.; Lindzey, F.G.; Keith, L.; Powell, J.H.; Abraham, A.A.
2007-01-01
Recent expansions by Rocky Mountain elk (Cervus elaphus) into nonforested habitats across the Intermountain West have required managers to reconsider the traditional paradigms of forage and cover as they relate to managing elk and their habitats. We examined seasonal habitat selection patterns of a hunted elk population in a nonforested high-desert region of southwestern Wyoming, USA. We used 35,246 global positioning system locations collected from 33 adult female elk to model probability of use as a function of 6 habitat variables: slope, aspect, elevation, habitat diversity, distance to shrub cover, and distance to road. We developed resource selection probability functions for individual elk, and then we averaged the coefficients to estimate population-level models for summer and winter periods. We used the population-level models to generate predictive maps by assigning pixels across the study area to 1 of 4 use categories (i.e., high, medium-high, medium-low, or low), based on quartiles of the predictions. Model coefficients and predictive maps indicated that elk selected for summer habitats characterized by higher elevations in areas of high vegetative diversity, close to shrub cover, northerly aspects, moderate slopes, and away from roads. Winter habitat selection patterns were similar, except elk shifted to areas with lower elevations and southerly aspects. We validated predictive maps by using 528 locations collected from an independent sample of radiomarked elk (n = 55) and calculating the proportion of locations that occurred in each of the 4 use categories. Together, the high- and medium-high use categories of the summer and winter predictive maps contained 92% and 74% of summer and winter elk locations, respectively. Our population-level models and associated predictive maps were successful in predicting winter and summer habitat use by elk in a nonforested environment. In the absence of forest cover, elk seemed to rely on a combination of shrubs
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Sinu, Palatty Allesh
2017-01-01
Abstract Wetland ecosystems, particularly the mangrove forest, are the primary wild habitat of heronry birds. However, urban ecosystems have become a favorite breeding habitat of these birds. To provide inputs into the habitat management for conservation of these birds, we investigated the quantitative and qualitative characteristics of nesting trees of heronry birds in the urban environment of the North Kerala region of peninsular India. Census on nesting trees was done in 3 major microhabitats of the urban ecosystem: avenues of national highways and towns, nonresidential plots, and residential areas apart from the mangrove islets in the peri-urban locality. The study found that 174 trees of 22 species hosted 1,928 heronry bird nests in the urban habitats; mangrove forests, although plentiful in the study area, hosted only about 20% of the total nests encountered in the study. Rain trees Samanea saman (43.7%) were the most available nesting tree. The greatest number of nests and nesting trees were encountered on the roads of urban areas, followed by nonresidential areas and residential areas. The differences in the observed frequencies of nesting trees in 3 microhabitats and in 3 types of roads (national highways > state highways > small pocket road) were significant. Canopy spread, girth size, and quality of the trees predicted the tree selection of the heronry birds in urban environments. Therefore, we recommend proper management and notification of the identified nesting trees as protected sites for the conservation of herorny birds. PMID:29492020
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Roshnath, Ramesh; Sinu, Palatty Allesh
2017-12-01
Wetland ecosystems, particularly the mangrove forest, are the primary wild habitat of heronry birds. However, urban ecosystems have become a favorite breeding habitat of these birds. To provide inputs into the habitat management for conservation of these birds, we investigated the quantitative and qualitative characteristics of nesting trees of heronry birds in the urban environment of the North Kerala region of peninsular India. Census on nesting trees was done in 3 major microhabitats of the urban ecosystem: avenues of national highways and towns, nonresidential plots, and residential areas apart from the mangrove islets in the peri-urban locality. The study found that 174 trees of 22 species hosted 1,928 heronry bird nests in the urban habitats; mangrove forests, although plentiful in the study area, hosted only about 20% of the total nests encountered in the study. Rain trees Samanea saman (43.7%) were the most available nesting tree. The greatest number of nests and nesting trees were encountered on the roads of urban areas, followed by nonresidential areas and residential areas. The differences in the observed frequencies of nesting trees in 3 microhabitats and in 3 types of roads (national highways > state highways > small pocket road) were significant. Canopy spread, girth size, and quality of the trees predicted the tree selection of the heronry birds in urban environments. Therefore, we recommend proper management and notification of the identified nesting trees as protected sites for the conservation of herorny birds.
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Microcomputer software for calculating the western Oregon elk habitat effectiveness index.
Alan Ager; Mark Hitchcock
1992-01-01
This paper describes the operation of the microcomputer program HEIWEST, which was developed to automate calculation of the western Oregon elk habitat effectiveness index (HEI). HEIWEST requires little or no training to operate and vastly simplifies the task of measuring HEI for either site-specific project analysis or long-term monitoring of elk habitat. It is...
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Stress tolerance in plants via habitat-adapted symbiosis
Rodriguez, R.J.; Henson, J.; Van Volkenburgh, E.; Hoy, M.; Wright, L.; Beckwith, F.; Kim, Y.-O.; Redman, R.S.
2008-01-01
We demonstrate that native grass species from coastal and geothermal habitats require symbiotic fungal endophytes for salt and heat tolerance, respectively. Symbiotically conferred stress tolerance is a habitat-specific phenomenon with geothermal endophytes conferring heat but not salt tolerance, and coastal endophytes conferring salt but not heat tolerance. The same fungal species isolated from plants in habitats devoid of salt or heat stress did not confer these stress tolerances. Moreover, fungal endophytes from agricultural crops conferred disease resistance and not salt or heat tolerance. We define habitat-specific, symbiotically-conferred stress tolerance as habitat-adapted symbiosis and hypothesize that it is responsible for the establishment of plants in high-stress habitats. The agricultural, coastal and geothermal plant endophytes also colonized tomato (a model eudicot) and conferred disease, salt and heat tolerance, respectively. In addition, the coastal plant endophyte colonized rice (a model monocot) and conferred salt tolerance. These endophytes have a broad host range encompassing both monocots and eudicots. Interestingly, the endophytes also conferred drought tolerance to plants regardless of the habitat of origin. Abiotic stress tolerance correlated either with a decrease in water consumption or reactive oxygen sensitivity/generation but not to increased osmolyte production. The ability of fungal endophytes to confer stress tolerance to plants may provide a novel strategy for mitigating the impacts of global climate change on agricultural and native plant communities.The ISME Journal (2008) 2, 404-416; doi:10.1038/ismej.2007.106; published online 7 February 2008. ?? 2008 International Society for Microbial Ecology All rights reserved.
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Habitat use and preferences of breeding female wood ducks
Hartke, Kevin M.; Hepp, G.R.
2004-01-01
ducks can satisfy requirements for egg production using a variety of wetland habitats. We suggest that providing a diversity of habitat types will increase the probability of meeting needs of breeding females throughout the breeding season, especially in areas where wetland conditions frequently change.
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Habitat use and habitat overlap of riparian birds in three elevational zones
Deborah M. Finch
1989-01-01
I examined patterns of variance in habitat use and habitat overlap in 20 breeding bird species found along a riparian vegetational gradient in southeastern Wyoming to test whether habitat use in species differed (1) from availability of random habitat resources, (2) among elevational zones, and (3) between species that inhabited only one zone and species that occupied...
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Workstation Designs for a Cis-Lunar Deep Space Habitat
NASA Technical Reports Server (NTRS)
Howe, A. Scott
2014-01-01
Using the International Standard Payload Rack (ISPR) system, a suite of workstations required for deep space missions have been proposed to fill out habitation functions in an International Space Station (ISS) derived Cis-lunar Deep Space Habitat. This paper introduces the functional layout of the Cis-lunar habitat design, and describes conceptual designs for modular deployable work surfaces, General Maintenance Workstation (GMWS), In-Space Manufacturing Workstation (ISMW), Intra-Vehicular Activity Telerobotics Work Station (IVA-TRWS), and Galley / Wardroom.
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This chapter summarizes and evaluated the habitat assessment protocols of five agencies, USEPA/EMAP/SW, USGS/NAWQA, USEPA/RBP, Ohio EPA, and MDNR/MBSS. It begins with a description of the origin of the habitat indices most widely used by these agencies. Then the habitat assessmen...
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Predator diversity reduces habitat colonization by mosquitoes and midges.
Staats, Ethan G; Agosta, Salvatore J; Vonesh, James R
2016-12-01
Changes in predator diversity via extinction and invasion are increasingly widespread and can have important ecological and socio-economic consequences. Anticipating and managing these consequences requires understanding how predators shape ecological communities. Previous predator biodiversity research has focused on post-colonization processes. However, predators can also shape communities by altering patterns of prey habitat selection during colonization. The sensitivity of this non-consumptive top down mechanism to changes in predator diversity is largely unexamined. To address this gap, we examined patterns of dipteran oviposition habitat selection in experimental aquatic habitats in response to varied predator species richness while holding predator abundance constant. Caged predators were used in order to disentangle behavioural oviposition responses to predator cues from potential post-oviposition consumption of eggs and larvae. We hypothesized that because increases in predator richness often result in greater prey mortality than would be predicted from independent effects of predators, prey should avoid predator-rich habitats during colonization. Consistent with this hypothesis, predator-rich habitats received 48% fewer dipteran eggs than predicted, including 60% fewer mosquito eggs and 38% fewer midge eggs. Our findings highlight the potentially important links between predator biodiversity, prey habitat selection and the ecosystem service of pest regulation. © 2016 The Author(s).
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Chapter 15: Inland Habitat Suitability for the Marbled Murrelet in Southcentral Alaska
Katherine J. Kuletz; Dennis K. Marks; Nancy L. Naslund; Nike J. Goodson; Mary B. Cody
1995-01-01
The majority of Marbled Murrelets (Brachyramphus marmoratus) nest in Alaska, where they sometimes nest on the ground, and their nesting habitat requirements are not well understood. The inland activity of murrelets was surveyed, and habitat features measured, between 1991 and 1993, in Prince William Sound, Kenai Fjords National Park and Afognak...
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Habitat-specific foraging of prothonotary warblers: Deducing habitat quality
Lyons, J.E.
2005-01-01
Foraging behavior often reflects food availability in predictable ways. For example, in habitats where food availability is high, predators should attack prey more often and move more slowly than in habitats where food availability is low. To assess relative food availability and habitat quality, I studied the foraging behavior of breeding Prothonotary Warblers (Protonotaria citrea) in two forest habitat types, cypress-gum swamp forest and coastal-plain levee forest. I quantified foraging behavior with focal animal sampling and continuous recording during foraging bouts. I measured two aspects of foraging behavior: 1) prey attack rate (attacks per minute), using four attack maneuvers (glean, sally, hover, strike), and 2) foraging speed (movements per minute), using three types of movement (hop, short flight [???1 m], long flight [>1 m]). Warblers attacked prey more often in cypress-gum swamp forest than in coastal-plain levee forest. Foraging speed, however, was not different between habitats. I also measured foraging effort (% time spent foraging) and relative frequency of attack maneuvers employed in each habitat; neither of these variables was influenced by forest type. I conclude that Prothonotary Warblers encounter more prey when foraging in cypress-gum swamps than in coastal-plain levee forest, and that greater food availability results in higher density and greater reproductive success for birds breeding in cypress-gum swamp.
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Tracking changes and preventing loss in critical tiger habitat
Joshi, Anup R.; Dinerstein, Eric; Wikramanayake, Eric; Anderson, Michael L.; Olson, David; Jones, Benjamin S.; Seidensticker, John; Lumpkin, Susan; Hansen, Matthew C.; Sizer, Nigel C.; Davis, Crystal L.; Palminteri, Suzanne; Hahn, Nathan R.
2016-01-01
The global population of wild tigers remains dangerously low at fewer than 3500 individuals. Habitat loss, along with poaching, can undermine the international target recovery of doubling the number of wild tigers by 2022. Using a new satellite-based monitoring system, we analyzed 14 years of forest loss data within the 76 landscapes (ranging from 278 to 269,983 km2) that have been prioritized for conservation of wild tigers. Our analysis provides an update of the status of tiger habitat and describes new applications of technology to detect precisely where forest loss is occurring in order to curb future habitat loss. Across the 76 landscapes, forest loss was far less than anticipated (79,597 ± 22,629 km2, 7.7% of remaining habitat) over the 14-year study period (2001–2014). Habitat loss was unevenly distributed within a subset of 29 landscapes deemed most critical for doubling wild tiger populations: 19 showed little change (1.5%), whereas 10 accounted for more than 98% (57,392 ± 16,316 km2) of habitat loss. Habitat loss in source population sites within 76 landscapes ranged from no loss to 435 ± 124 km2 (x¯=24km2, SD = 89, total = 1676 ± 476 km2). Doubling the tiger population by 2022 requires moving beyond tracking annual changes in habitat. We highlight near–real-time forest monitoring technologies that provide alerts of forest loss at relevant spatial and temporal scales to prevent further erosion. PMID:27051881
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Rickman, Ronald L.
1998-01-01
A minimum flow of 40 cubic feet per second is required in the lower Bradley River, near Homer, Alaska, from November 2 to April 30 to ensure adequate habitat for salmon incubation. The study that determined this minimum flow did not account for the effects of ice formation on habitat. The limiting factor for determining the minimal acceptable flow limit appears to be stream-water velocity. The minimum short-term flow needed to ensure adequate salmon incubation habitat when ice is present is about 30 cubic feet per second. For long-term flows, 40 cubic feet per second is adequate when ice is present. Long-term minimum discharge needed to ensure adequate incubation habitat--which is based on mean velocity alone--is as follows: 40 cubic feet per second when ice is forming; 35 cubic feet per second for stable and eroding ice conditions; and 30 cubic feet per second for ice-free conditions. The effects of long-term streamflow less than 40 cubic feet per second on fine-sediment deposition and dissolved-oxygen interchange could not be extrapolated from the data. Hydrologic properties and water-quality data were measured in winter only from March 1993 to April 1998 at six transects in the lower Bradley River under three phases of icing: forming, stable, and eroding. Discharge in the lower Bradley River ranged from 33.3 to 73.0 cubic feet per second during all phases of ice formation and ice conditions, which ranged from ice free to 100 percent ice cover. Hydrostatic head was adequate for habitat protection for all ice phases and discharges. Mean stream velocity was adequate for all but one ice-forming episode. Velocity distribution within each transect varied significantly from one sampling period to the next. No relation was found between ice phase, discharge, and wetted perimeter. Intragravel-water temperature was slightly warmer than surface-water temperature. Surface- and intragravel-water dissolved-oxygen levels were adequate for all ice phases and discharges. No
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Coral reef fish predator maintains olfactory acuity in degraded coral habitats.
Natt, Michael; Lönnstedt, Oona M; McCormick, Mark I
2017-01-01
Coral reefs around the world are rapidly degrading due to a range of environmental stressors. Habitat degradation modifies the sensory landscape within which predator-prey interactions occur, with implications for olfactory-mediated behaviours. Predator naïve settlement-stage damselfish rely on conspecific damage-released odours (i.e., alarm odours) to inform risk assessments. Yet, species such as the Ambon damselfish, Pomacentrus amboinensis, become unable to respond appropriately to these cues when living in dead-degraded coral habitats, leading to increased mortality through loss of vigilance. Reef fish predators also rely on odours from damaged prey to locate, assess prey quality and engage in prey-stealing, but it is unknown whether their responses are also modified by the change to dead-degraded coral habitats. Implications for prey clearly depend on how their predatory counterparts are affected, therefore the present study tested whether olfactory-mediated foraging responses in the dusky dottyback, Pseudochromis fuscus, a common predator of P. amboinensis, were similarly affected by coral degradation. A y-maze was used to measure the ability of Ps. fuscus to detect and move towards odours, against different background water sources. Ps. fuscus were exposed to damage-released odours from juvenile P. amboinensis, or a control cue of seawater, against a background of seawater treated with either healthy or dead-degraded hard coral. Predators exhibited an increased time allocation to the chambers of y-mazes injected with damage-released odours, with comparable levels of response in both healthy and dead-degraded coral treated waters. In control treatments, where damage-released odours were replaced with a control seawater cue, fish showed no increased preference for either chamber of the y-maze. Our results suggest that olfactory-mediated foraging behaviours may persist in Ps. fuscus within dead-degraded coral habitats. Ps. fuscus may consequently gain a
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Food web structure shaped by habitat size and climate across a latitudinal gradient.
Romero, Gustavo Q; Piccoli, Gustavo C O; de Omena, Paula M; Gonçalves-Souza, Thiago
2016-10-01
Habitat size and climate are known to affect the trophic structure and dynamics of communities, but their interactive effects are poorly understood. Organisms from different trophic levels vary in terms of metabolic requirements and heat dissipation. Indeed, larger species such as keystone predators require more stable climatic conditions than their prey. Likewise, habitat size disproportionally affects large-sized predators, which require larger home ranges and are thus restricted to larger habitats. Therefore, food web structure in patchy ecosystems is expected to be shaped by habitat size and climate variations. Here we investigate this prediction using natural aquatic microcosm (bromeliad phytotelmata) food webs composed of litter resources (mainly detritus), detritivores, mesopredators, and top predators (damselflies). We surveyed 240 bromeliads of varying sizes (water retention capacity) across 12 open restingas in SE Brazil spread across a wide range of tropical latitudes (-12.6° to -27.6°, ca. 2,000 km) and climates (Δ mean annual temperature = 5.3°C). We found a strong increase in predator-to-detritivore mass ratio with habitat size, which was representative of a typical inverted trophic pyramid in larger ecosystems. However, this relationship was contingent among the restingas; slopes of linear models were steeper in more stable and favorable climates, leading to inverted trophic pyramids (and top-down control) being more pronounced in environments with more favorable climatic conditions. By contrast, detritivore-resource and mesopredator-detritivore mass ratios were not affected by habitat size or climate variations across latitudes. Our results highlight that the combined effects of habitat size, climate and predator composition are pivotal to understanding the impacts of multiple environmental factors on food web structure and dynamics. © 2016 by the Ecological Society of America.
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Snag habitat management: Proceedings of the symposium
Jerry W. Davis; Gregory A. Goodwin; Richard A. Ockenfels
1983-01-01
These proceedings include 41 papers focusing attention on the need to integrate management of snags - dead or deteriorating trees critical to needs of cavity-dependent wildlife - with other resource uses and demands. Sessions concentrated on management, habitat and species requirements, and monitoring and modeling.
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Andrea Havron; Chris Goldfinger; Sarah Henkel; Bruce G. Marcot; Chris Romsos; Lisa Gilbane
2017-01-01
Resource managers increasingly use habitat suitability map products to inform risk management and policy decisions. Modeling habitat suitability of data-poor species over large areas requires careful attention to assumptions and limitations. Resulting habitat suitability maps can harbor uncertainties from data collection and modeling processes; yet these limitations...
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NASA Astrophysics Data System (ADS)
Cienciala, P.; Nelson, A. D.
2017-12-01
The field of fluvial eco-geomorphology strives to improve the understanding of interactions between physical and biological processes in running waters. This body of research has greatly contributed to the advancement of integrated river science and management. Arguably, the most popular research themes in eco-geomorphology include hydrogemorphic controls of habitat quality and effects of disturbances such as floods, sediment transport events or sediment accumulation. However, in contrast to the related field of ecology, the distinction between direct and indirect mechanisms which may affect habitat quality and biotic response to disturbance has been poorly explored in eco-geomorphic research. This knowledge gap poses an important challenge for interpretations of field observations and model development. In this research, using the examples of benthic invertebrates and fish, we examine the importance of direct and indirect influences that geomorphic and hydraulic processes may exert on stream biota. We also investigate their implications for modeling of organism-habitat relationships. To achieve our goal, we integrate field and remote sensing data from montane streams in the Pacific Northwest region with habitat models. Preliminary results indicate that indirect hydrogeomorphic influences of stream organisms, such as those mediated by altered availability of food resources, can be as important as direct influences (e.g. physical disturbance). We suggest that these findings may also have important implications for modeling of riverine habitat.
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Grijalva, M J; Villacis, A G
2009-05-01
The main vectors of Chagas disease in Ecuador are Triatoma dimidiata and Rhodnius ecuadoriensis. The latter species occupies domestic and peridomestic habitats, as well as sylvatic ecotopes--particularly associated with Phytelephas aequatorialis palm trees--in the western coastal region of Ecuador. In the southern highlands, however, such palm tree habitats are uncommon, and sylvatic populations of R. ecuadoriensis have not previously been reported to date. This study was carried out in five rural communities in Loja Province in southern Ecuador, where manual triatomine searches were conducted in various sylvatic habitats. A total of 81 squirrel nests (Sciurus stramineus) and > 200 bird nests and other habitats were searched. One hundred three R. ecuadoriensis individuals were found in 11 squirrel nests (infestation index = 13.6%, density = 2 bugs per nest searched, crowding = 9.5 bugs per infested nest, colonization index = 72.7% of infested nests with nymphs). No triatomines were found in bird nests or other sylvatic habitats. The presence of sylvatic R. ecuadoriensis in the southern highlands of Ecuador has important implications for the long-term control of Chagas disease in the region because of the possibility of reinfestation of dwellings after insecticide-based control interventions.
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Sabbah, Shai; Gray, Suzanne M; Boss, Emmanuel S; Fraser, James M; Zatha, Richard; Hawryshyn, Craig W
2011-02-01
Lake Malawi boasts the highest diversity of freshwater fishes in the world. Nearshore sites are categorized according to their bottom substrate, rock or sand, and these habitats host divergent assemblages of cichlid fishes. Sexual selection driven by mate choice in cichlids led to spectacular diversification in male nuptial coloration. This suggests that the spectral radiance contrast of fish, the main determinant of visibility under water, plays a crucial role in cichlid visual communication. This study provides the first detailed description of underwater irradiance, radiance and beam attenuation at selected sites representing two major habitats in Lake Malawi. These quantities are essential for estimating radiance contrast and, thus, the constraints imposed on fish body coloration. Irradiance spectra in the sand habitat were shifted to longer wavelengths compared with those in the rock habitat. Beam attenuation in the sand habitat was higher than in the rock habitat. The effects of water depth, bottom depth and proximity to the lake bottom on radiometric quantities are discussed. The radiance contrast of targets exhibiting diffused and spectrally uniform reflectance depended on habitat type in deep water but not in shallow water. In deep water, radiance contrast of such targets was maximal at long wavelengths in the sand habitat and at short wavelengths in the rock habitat. Thus, to achieve conspicuousness, color patterns of rock- and sand-dwelling cichlids would be restricted to short and long wavelengths, respectively. This study provides a useful platform for the examination of cichlid visual communication.
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Duke, Norman C; Bell, Alicia M; Pederson, Dan K; Roelfsema, Chris M; Bengtson Nash, Susan
2005-01-01
Herbicides, particularly diuron, were correlated with severe and widespread dieback of the dominant mangrove, Avicennia marina (Forsk.) Vierh. var. eucalyptifolia (Val.) N.C. Duke (Avicenniaceae), its reduced canopy condition, and declines in seedling health within three neighbouring estuaries in the Mackay region of NE Australia. This unusual species-specific dieback, first observed in the early 1990s, had gotten notably worse by 2002 to affect >30 km(2) of mangroves in at least five adjacent estuaries in the region. Over the past century, agricultural production has responded well to the demands of increasing population with improvements in farm efficiency assisted by significant increases in the use of agricultural chemicals. However, with regular and episodic river flow events, these chemicals have sometimes found their way into estuarine and nearshore water and sediments where their effects on marine habitats have been largely unquantified. Investigations over the last three years in the Mackay region provide compelling evidence of diuron, and possibly other agricultural herbicides, as the most likely cause of the severe and widespread mangrove dieback. The likely consequences of such dieback included declines in coastal water quality with increased turbidity, nutrients and sediment deposition, as well as further dispersal of the toxic chemicals. The implications of such findings are immense since they describe not only the serious deterioration of protected and beneficial mangrove habitat but also the potential for significant direct and indirect effects on other highly-valued estuarine and marine habitats in the region, including seagrass beds and coral reefs of the Great Barrier Reef lagoon. This article reviews all key findings and observations to date and describes the essential correlative and causative evidence.
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NASA Astrophysics Data System (ADS)
Streich, M.; Wetz, J. J.; Ajemian, M. J.; Stunz, G. W.
2016-02-01
The goal of our study was to evaluate the relative abundance, size and age structure of Red Snapper among three different habitat types (standing oil and gas platforms, artificial reefs [rigs-to-reefs], and natural banks) in the northwestern Gulf of Mexico. From May 2013 - January 2015, we conducted 140 vertical line sets and captured 1538 Red Snapper ranging in size from 251 to 855 mm TL. Ages determined for 801 of these fish ranged from 2-30 years. No differences were detected in Red Snapper CPUE among the three habitats. However, a comparison of TL and TW distributions suggested that natural banks supported a greater proportion of larger fish than artificial reefs or standing platforms (K-S test, p<0.001). Mean TW-at-age regressions for the most common age groups (ages 3-7) suggested that Red Snapper grew faster at artificial reefs and standing platforms than natural bank habitats (ANCOVA, p<0.05). Mean age was positively correlated with capture depth (r=0.79) suggesting spatial variation in age composition. These results have important implications for artificial reef development and Red Snapper management in the GOM. Further use of standardized, fishery-independent surveys and additional biological data will help elucidate the role artificial structures play in maintaining the Red Snapper population.
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Room to Live: the sizing of Lunar and Martian Habitats
NASA Technical Reports Server (NTRS)
McGregor, Walter L.
2006-01-01
In order for man to return to space or extra terrestrial bodies for long duration missions it is important that adequate habitat volume be defined early to avoid costly delays and redesign. To properly define a habitat volume two major factors need to be considered. The first factor is the free or open space. This is the space that allows the crew room to move about the habitat. This space will vary based on crew size and length of the mission. The second major factor is the stowage space required for equipment and supplies. This includes both fixed volumes and consumables. Fixed volumes include items such as tools, communication equipment, Advanced Life Support (ALS) equipment, and support equipment. Consumables include items like filters, food, water and oxygen. This space is also dependent on crew size and mission length. A review of past missions into alien environments, such as deep sea habitats as well as space based habitats will be used to validate the assumption made in this paper. Once these key factors are defined trades must be run to optimize the overall volume of a habitat. This includes trades of disposable vs. reusable for items such as clothing, dishes, and water. Another factor to consider is the availability of in situ resources to aid in the construction of the habitat structure as well as re-supply of consumable items. A review of past missions into alien environments, such as deep sea habitats as well as space based habitats will be used to validate the assumption made in this paper. The result is a habitat sizing tool to provide a first order estimate of habitat volumes for extended mission to the surface of the moon and Mars.
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Coefficients of productivity for Yellowstone's grizzly bear habitat
Mattson, David John; Barber, Kim; Maw, Ralene; Renkin, Roy
2004-01-01
This report describes methods for calculating coefficients used to depict habitat productivity for grizzly bears in the Yellowstone ecosystem. Calculations based on these coefficients are used in the Yellowstone Grizzly Bear Cumulative Effects Model to map the distribution of habitat productivity and account for the impacts of human facilities. The coefficients of habitat productivity incorporate detailed information that was collected over a 20-year period (1977-96) on the foraging behavior of Yellowstone's bears and include records of what bears were feeding on, when and where they fed, the extent of that feeding activity, and relative measures of the quantity consumed. The coefficients also incorporate information, collected primarily from 1986 to 1992, on the nutrient content of foods that were consumed, their digestibility, characteristic bite sizes, and the energy required to extract and handle each food. Coefficients were calculated for different time periods and different habitat types, specific to different parts of the Yellowstone ecosystem. Stratifications included four seasons of bear activity (spring, estrus, early hyperphagia, late hyperphagia), years when ungulate carrion and whitebark pine seed crops were abundant versus not, areas adjacent to (< 100 m) or far away from forest/nonforest edges, and areas inside or outside of ungulate winter ranges. Densities of bear activity in each region, habitat type, and time period were incorporated into calculations, controlling for the effects of proximity to human facilities. The coefficients described in this report and associated estimates of grizzly bear habitat productivity are unique among many efforts to model the conditions of bear habitat because calculations include information on energetics derived from the observed behavior of radio-marked bears.
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Knick, Steven T.; Rotenberry, J.T.
2000-01-01
Models of habitat associations for species often are developed with an implicit assumption that habitats are static, even though recent disturbance may have altered the landscape. We tested our hypothesis that trajectory and magnitude of habitat change influenced observed distribution and abundance of passerine birds breeding in shrubsteppe habitats of southwestern Idaho. Birds in this region live in dynamic landscapes undergoing predominantly large-scale, radical, and unidirectional habitat change because wildfires are converting shrublands into expanses of exotic annual grasslands. We used data from field surveys and satellite image analyses in a series of redundancy analyses to partition variances and to determine the relative contribution of habitat change and current landscapes. Although current habitats explained a greater proportion of total variation, changes in habitat and measures of habitat richness and texture also contributed to variation in abundance of Horned Larks (Eremophila alpestris), Brewera??s Sparrows (Spizella breweri), and Sage Sparrows (Amphispiza belli). Abundance of birds was insensitive to scale for nonspatial habitat variables. In contrast, spatial measures of habitat richness and texture in the landscape were significant only at large spatial scales. Abundance of Horned Larks, Western Meadowlarks (Sturnella neglecta), and Brewera??s Sparrows, but not Sage Thrashers (Oreoscoptes montanus) or Sage Sparrows, was positively correlated with changes toward stable habitats. Because dominant habitat changes were toward less stable conditions, regional declines of those birds in shrubsteppe habitats reflect current landscapes as well as the history, magnitude, and trajectory of habitat change.
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Anglin, Donald R.; Haeseker, Steven L.; Skalicky, Joseph J.; Schaller, Howard; Tiffan, Kenneth F.; Hatten, James R.; Hoffarth, Paul; Nugent, John; Benner, David; Yoshinaka, Marv
2006-01-01
This report describes research conducted primarily in 2003 and 2004 to evaluate the effects of upstream dam operations on spawning and rearing conditions for fall Chinook salmon, Oncorhynchus tshawytscha, in the Hanford Reach of the Columbia River. Results from habitat modeling tasks which continued in 2005 and 2006 are also included in this report. This study is focused on the effects of streamflows and streamflow fluctuations on 1) entrapment and entrapment mortality of juveniles, 2) adult spawning habitat, and 3) juvenile rearing habitat. An independent peer review was conducted on the draft version of this report utilizing three reviewers, each with different areas of expertise and different levels of knowledge regarding hydrodynamic modeling, fall Chinook biology, life history, and habitat requirements, and fishery issues relating to hydropower development and operations. Peer review comments have been incorporated into this final version.
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Global rates of habitat loss and implications for amphibian conservation
Gallant, Alisa L.; Klaver, R.W.; Casper, G.S.; Lannoo, M.J.
2007-01-01
A large number of factors are known to affect amphibian population viability, but most authors agree that the principal causes of amphibian declines are habitat loss, alteration, and fragmentation. We provide a global assessment of land use dynamics in the context of amphibian distributions. We accomplished this by compiling global maps of amphibian species richness and recent rates of change in land cover, land use, and human population growth. The amphibian map was developed using a combination of published literature and digital databases. We used an ecoregion framework to help interpret species distributions across environmental, rather than political, boundaries. We mapped rates of land cover and use change with statistics from the World Resources Institute, refined with a global digital dataset on land cover derived from satellite data. Temporal maps of human population were developed from the World Resources Institute database and other published sources. Our resultant map of amphibian species richness illustrates that amphibians are distributed in an uneven pattern around the globe, preferring terrestrial and freshwater habitats in ecoregions that are warm and moist. Spatiotemporal patterns of human population show that, prior to the 20th century, population growth and spread was slower, most extensive in the temperate ecoregions, and largely exclusive of major regions of high amphibian richness. Since the beginning of the 20th century, human population growth has been exponential and has occurred largely in the subtropical and tropical ecoregions favored by amphibians. Population growth has been accompanied by broad-scale changes in land cover and land use, typically in support of agriculture. We merged information on land cover, land use, and human population growth to generate a composite map showing the rates at which humans have been changing the world. When compared with the map of amphibian species richness, we found that many of the regions of the
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Habitat capability model for birds wintering in the Black Hills, South Dakota
Mark A. Rumble; Todd R. Mills; Lester D. Flake
1999-01-01
Birds are sensitive indicators of vegetation conditions because they have relatively narrow habitat requirements (Martin and Finch 1995). Resident bird populations are relatively stable in winter (Ralph et al. 1993) and more closely associated with specific habitats than during summer (Huff et al. 1991, Manuwal and Huff 1987). Winter can be critical for birds in...
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Nuptial coloration of red shiners ( Cyprinella lutrensis) is more intense in turbid habitats
NASA Astrophysics Data System (ADS)
Dugas, Matthew B.; Franssen, Nathan R.
2011-03-01
Communication is shaped and constrained by the signaling environment. In aquatic habitats, turbidity can reduce both the quantity and quality of ambient light and has been implicated in the breakdown of visual signaling. Here, we examined the relationship between turbidity (quantified with long-term data) and the expression of carotenoid-based nuptial coloration in the red shiner ( Cyprinella lutrensis), a small-bodied cyprinid. Males in more turbid habitats displayed redder fins, and an experimental manipulation of adult diet suggested that carotenoid intake alone did not explain among-population color differences. These results run counter to similar studies where signal expression decreased in turbid conditions, and may be explained by the non-territorial red shiner mating system, interactions between the mechanism of coloration and the signaling environment, or reduced cost of color expression in turbid habitats (e.g., reduced predation risk). Our results highlight how the behavioral and ecological contexts in which signals function can shape evolutionary responses to the environment.
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Coastal vertebrate exposure to predicted habitat changes due to sea level rise
Hunter, Elizabeth A.; Nibbelink, Nathan P.; Alexander, Clark R.; Barrett, Kyle; Mengak, Lara F.; Guy, Rachel; Moore, Clinton; Cooper, Robert J.
2015-01-01
Sea level rise (SLR) may degrade habitat for coastal vertebrates in the Southeastern United States, but it is unclear which groups or species will be most exposed to habitat changes. We assessed 28 coastal Georgia vertebrate species for their exposure to potential habitat changes due to SLR using output from the Sea Level Affecting Marshes Model and information on the species’ fundamental niches. We assessed forecasted habitat change up to the year 2100 using three structural habitat metrics: total area, patch size, and habitat permanence. Almost all of the species (n = 24) experienced negative habitat changes due to SLR as measured by at least one of the metrics. Salt marsh and ocean beach habitats experienced the most change (out of 16 categorical land cover types) across the three metrics and species that used salt marsh extensively (rails and marsh sparrows) were ranked highest for exposure to habitat changes. Species that nested on ocean beaches (Diamondback Terrapins, shorebirds, and terns) were also ranked highly, but their use of other foraging habitats reduced their overall exposure. Future studies on potential effects of SLR on vertebrates in southeastern coastal ecosystems should focus on the relative importance of different habitat types to these species’ foraging and nesting requirements. Our straightforward prioritization approach is applicable to other coastal systems and can provide insight to managers on which species to focus resources, what components of their habitats need to be protected, and which locations in the study area will provide habitat refuges in the face of SLR.
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Coastal Vertebrate Exposure to Predicted Habitat Changes Due to Sea Level Rise.
Hunter, Elizabeth A; Nibbelink, Nathan P; Alexander, Clark R; Barrett, Kyle; Mengak, Lara F; Guy, Rachel K; Moore, Clinton T; Cooper, Robert J
2015-12-01
Sea level rise (SLR) may degrade habitat for coastal vertebrates in the Southeastern United States, but it is unclear which groups or species will be most exposed to habitat changes. We assessed 28 coastal Georgia vertebrate species for their exposure to potential habitat changes due to SLR using output from the Sea Level Affecting Marshes Model and information on the species' fundamental niches. We assessed forecasted habitat change up to the year 2100 using three structural habitat metrics: total area, patch size, and habitat permanence. Almost all of the species (n = 24) experienced negative habitat changes due to SLR as measured by at least one of the metrics. Salt marsh and ocean beach habitats experienced the most change (out of 16 categorical land cover types) across the three metrics and species that used salt marsh extensively (rails and marsh sparrows) were ranked highest for exposure to habitat changes. Species that nested on ocean beaches (Diamondback Terrapins, shorebirds, and terns) were also ranked highly, but their use of other foraging habitats reduced their overall exposure. Future studies on potential effects of SLR on vertebrates in southeastern coastal ecosystems should focus on the relative importance of different habitat types to these species' foraging and nesting requirements. Our straightforward prioritization approach is applicable to other coastal systems and can provide insight to managers on which species to focus resources, what components of their habitats need to be protected, and which locations in the study area will provide habitat refuges in the face of SLR.
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Coastal Vertebrate Exposure to Predicted Habitat Changes Due to Sea Level Rise
NASA Astrophysics Data System (ADS)
Hunter, Elizabeth A.; Nibbelink, Nathan P.; Alexander, Clark R.; Barrett, Kyle; Mengak, Lara F.; Guy, Rachel K.; Moore, Clinton T.; Cooper, Robert J.
2015-12-01
Sea level rise (SLR) may degrade habitat for coastal vertebrates in the Southeastern United States, but it is unclear which groups or species will be most exposed to habitat changes. We assessed 28 coastal Georgia vertebrate species for their exposure to potential habitat changes due to SLR using output from the Sea Level Affecting Marshes Model and information on the species' fundamental niches. We assessed forecasted habitat change up to the year 2100 using three structural habitat metrics: total area, patch size, and habitat permanence. Almost all of the species ( n = 24) experienced negative habitat changes due to SLR as measured by at least one of the metrics. Salt marsh and ocean beach habitats experienced the most change (out of 16 categorical land cover types) across the three metrics and species that used salt marsh extensively (rails and marsh sparrows) were ranked highest for exposure to habitat changes. Species that nested on ocean beaches (Diamondback Terrapins, shorebirds, and terns) were also ranked highly, but their use of other foraging habitats reduced their overall exposure. Future studies on potential effects of SLR on vertebrates in southeastern coastal ecosystems should focus on the relative importance of different habitat types to these species' foraging and nesting requirements. Our straightforward prioritization approach is applicable to other coastal systems and can provide insight to managers on which species to focus resources, what components of their habitats need to be protected, and which locations in the study area will provide habitat refuges in the face of SLR.
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Does Wyoming's Core Area Policy Protect Winter Habitats for Greater Sage-Grouse?
Smith, Kurt T; Beck, Jeffrey L; Pratt, Aaron C
2016-10-01
Conservation reserves established to protect important habitat for wildlife species are used world-wide as a wildlife conservation measure. Effective reserves must adequately protect year-round habitats to maintain wildlife populations. Wyoming's Sage-Grouse Core Area policy was established to protect breeding habitats for greater sage-grouse (Centrocercus urophasianus). Protecting only one important seasonal habitat could result in loss or degradation of other important habitats and potential declines in local populations. The purpose of our study was to identify the timing of winter habitat use, the extent which individuals breeding in Core Areas used winter habitats, and develop resource selection functions to assess effectiveness of Core Areas in conserving sage-grouse winter habitats in portions of 5 Core Areas in central and north-central Wyoming during winters 2011-2015. We found that use of winter habitats occured over a longer period than current Core Area winter timing stipulations and a substantial amount of winter habitat outside of Core Areas was used by individuals that bred in Core Areas, particularly in smaller Core Areas. Resource selection functions for each study area indicated that sage-grouse were selecting habitats in response to landscapes dominated by big sagebrush and flatter topography similar to other research on sage-grouse winter habitat selection. The substantial portion of sage-grouse locations and predicted probability of selection during winter outside small Core Areas illustrate that winter requirements for sage-grouse are not adequately met by existing Core Areas. Consequently, further considerations for identifying and managing important winter sage-grouse habitats under Wyoming's Core Area Policy are warranted.
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The biology of habitat dominance; can microbes behave as weeds?
Cray, Jonathan A; Bell, Andrew N W; Bhaganna, Prashanth; Mswaka, Allen Y; Timson, David J; Hallsworth, John E
2013-01-01
. Some microbes, such as Escherichia coli, Mycobacterium smegmatis and Pseudoxylaria spp., exhibit characteristics of both weed and non-weed species. We propose that the concept of nonweeds represents a ‘dustbin’ group that includes species such as Synodropsis spp., Polypaecilum pisce, Metschnikowia orientalis, Salmonella spp., and Caulobacter crescentus. We show that microbial weeds are conceptually distinct from plant weeds, microbial copiotrophs, r-strategists, and other ecophysiological groups of microorganism. Microbial weed species are unlikely to emerge from stationary-phase or other types of closed communities; it is open habitats that select for weed phenotypes. Specific characteristics that are common to diverse types of open habitat are identified, and implications of weed biology and open-habitat ecology are discussed in the context of further studies needed in the fields of environmental and applied microbiology. PMID:23336673
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Patrick, David A; Harper, Elizabeth B; Hunter, Malcolm L; Calhoun, Aram J K
2008-09-01
To predict the effects of terrestrial habitat change on amphibian populations, we need to know how amphibians respond to habitat heterogeneity, and whether habitat choice remains consistent throughout the life-history cycle. We conducted four experiments to evaluate how the spatial distribution of juvenile wood frogs, Rana sylvatica (including both overall abundance and localized density), was influenced by habitat choice and habitat structure, and how this relationship changed with spatial scale and behavioral phase. The four experiments included (1) habitat manipulation on replicated 10-ha landscapes surrounding breeding pools; (2) short-term experiments with individual frogs emigrating through a manipulated landscape of 1 m wide hexagonal patches; and habitat manipulations in (3) small (4-m2); and (4) large (100-m2) enclosures with multiple individuals to compare behavior both during and following emigration. The spatial distribution of juvenile wood frogs following emigration resulted from differences in the scale at which juvenile amphibians responded to habitat heterogeneity during active vs. settled behavioral phases. During emigration, juvenile wood frogs responded to coarse-scale variation in habitat (selection between 2.2-ha forest treatments) but not to fine-scale variation. After settling, however, animals showed habitat selection at much smaller scales (2-4 m2). This resulted in high densities of animals in small patches of suitable habitat where they experienced rapid mortality. No evidence of density-dependent habitat selection was seen, with juveniles typically choosing to remain at extremely high densities in high-quality habitat, rather than occupying low-quality habitat. These experiments demonstrate how prediction of the terrestrial distribution of juvenile amphibians requires understanding of the complex behavioral responses to habitat heterogeneity. Understanding these patterns is important, given that human alterations to amphibian habitats
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Duda, Michael; Kruckenhauser, Luise; Haring, Elisabeth; Sattmann, Helmut
2010-12-01
The habitat needs and potential threats to Trochulus oreinos oreinos (Wagner 1915) and Cylindrus obtusus (Draparnaud 1805) were assessed by comparing vegetation maps and our own records. We selected four sites from which we had adequate samples and for which exact vegetation maps were available: the mountains Hoch-schwab, Schneealpe, Rax and Schneeberg. Both taxa prefer open dry alpine grassland with diggable soil and/or stones. T. oreinos oreinos is restricted to subalpine and alpine boulder societies and Caricetum firmae . While C. obtusus dwells on several communities of plants, it seems to be bound to unconsolidated stony ground. As both taxa prefer naturally forest-free areas, they are not affected by structural changes of the habitat, such as reforestation caused by the abandonment of grazing and the shift of vegetation zones. But it has to be considered that T. oreinos oreinos and C. obtusus are limited by microclimatic factors, as they prefer cooler habitats. The mountains Schneealpe, Rax and Schneeberg, reaching barely 2000 m in height, are on the climatic limit of the species distribution. Therefore, the investigated taxa are vulnerable to the upward shift of climate zones. T. oreinos oreinos shows striking similarities in its habitat preference to the Swiss endemic T. biconicus , as both taxa prefer the same dry alpine habitats which are quite different to those of other representatives of the genus, which prefer damp habitats.
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Defining critical habitats of threatened and endemic reef fishes with a multivariate approach.
Purcell, Steven W; Clarke, K Robert; Rushworth, Kelvin; Dalton, Steven J
2014-12-01
Understanding critical habitats of threatened and endemic animals is essential for mitigating extinction risks, developing recovery plans, and siting reserves, but assessment methods are generally lacking. We evaluated critical habitats of 8 threatened or endemic fish species on coral and rocky reefs of subtropical eastern Australia, by measuring physical and substratum-type variables of habitats at fish sightings. We used nonmetric and metric multidimensional scaling (nMDS, mMDS), Analysis of similarities (ANOSIM), similarity percentages analysis (SIMPER), permutational analysis of multivariate dispersions (PERMDISP), and other multivariate tools to distinguish critical habitats. Niche breadth was widest for 2 endemic wrasses, and reef inclination was important for several species, often found in relatively deep microhabitats. Critical habitats of mainland reef species included small caves or habitat-forming hosts such as gorgonian corals and black coral trees. Hard corals appeared important for reef fishes at Lord Howe Island, and red algae for mainland reef fishes. A wide range of habitat variables are required to assess critical habitats owing to varied affinities of species to different habitat features. We advocate assessments of critical habitats matched to the spatial scale used by the animals and a combination of multivariate methods. Our multivariate approach furnishes a general template for assessing the critical habitats of species, understanding how these vary among species, and determining differences in the degree of habitat specificity. © 2014 Society for Conservation Biology.
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Ecosystem Services Linking People to Coastal Habitats ...
Background/Question/Methods: There is a growing need to incorporate and prioritize ecosystem services/condition information into land-use decision making. While there are a number of place-based studies looking at how land-use decisions affect the availability and delivery of coastal services, many of these methods require data, funding and/or expertise that may be inaccessible to many coastal communities. Using existing classification standards for beneficiaries and coastal habitats, (i.e., Final Ecosystem Goods and Services Classification System (FEGS-CS) and Coastal and Marine Ecological Classification Standard (CMECS)), a comprehensive literature review was coupled with a “weight of evidence” approach to evaluate linkages between beneficiaries and coastal habitat features most relevant to community needs. An initial search of peer-reviewed journal articles was conducted using JSTOR and ScienceDirect repositories identifying sources that provide evidence for coastal beneficiary:habitat linkages. Potential sources were further refined based on a double-blind review of titles, abstracts, and full-texts, when needed. Articles in the final list were then scored based on habitat/beneficiary specificity and data quality (e.g., indirect evidence from literature reviews was scored lower than direct evidence from case studies with valuation results). Scores were then incorporated into a weight of evidence framework summarizing the support for each benefici
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Krstolic, Jennifer L.
2015-01-01
Time-series analyses were used to investigate changes in habitat availability with increased water withdrawals of 10, 20, and almost 50 percent (48.6 percent) up to the 2040 amounts projected by local water supply plans. Adult and sub-adult smallmouth bass frequently had habitat availability outside the normal range for habitat conditions during drought years, yet 10- or 20-percent increases in withdrawals did not contribute to a large reduction in habitat. When withdrawals were increased by 50 percent, there was an additional decrease in habitat. During 2002 drought scenarios, reduced habitat availability for sub-adult redbreast sunfish or river chub was only slightly evident with 50-percent increased withdrawal scenarios. Recreational habitat represented by canoeing decreased lower than normal during the 2002 drought. For a recent normal year, like 2012, increased water-withdrawal scenarios did not affect habitat availability for fish such as adult and sub-adult smallmouth bass, sub-adult redbreast sunfish, or river chub. Canoeing habitat availability was within the normal range most of 2012, and increased water-withdrawal scenarios showed almost no affect. For both ecological fish habitat and recreational canoeing habitat, the antecedent conditions (habitat within normal range of habitat or below normal) appear to govern whether additional water withdrawals will affect habitat availability. As human populations and water demands increase, many of the ecological or recreational stresses may be lessened by managing the timing of water withdrawals from the system.
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Luo, Zhenhua; Liu, Bingwan; Liu, Songtao; Jiang, Zhigang; Halbrook, Richard S
2014-01-01
Human and livestock related disturbances of habitat selection by ungulates are topics of global concern, as they have profound impacts on ungulate survival, population density, fitness, and management; however, differences in ungulate habitat use under different human and livestock densities are not fully understood. Mongolian gazelle (Procapra gutturosa), an endemic ungulate species on the Asia-European steppe, faces varying intensities of human and livestock disturbances in the area around Dalai Lake, China. To investigate how habitat selection strategies vary as disturbance intensity changes, we randomly set 20 transects containing 1486 plots, on which we conducted repeated surveys of 21 ecological factors during the winters in the period of 2005-2008. We aimed to: 1) determine the critical factors underlying habitat selection of the gazelles; 2) determine the gazelles' habitat preferences in this area; 3) determine how habitat selection varies with disturbance intensity and explore the primary underlying mechanism. We used binary-logistic regressions and information theoretic approaches to build best-fit habitat selection models, and calculated resource selection functions. Sixty-six herds, 522 individuals, and 499 tracks were recorded. Our results indicate that snow depth and aboveground biomass are the main factors affecting habitat selection by Mongolian gazelle throughout the district in winter. Thin snow cover and abundant aboveground biomass are preferred. Avoiding disturbance was the primary factor accounting for habitat selection in low disturbance areas, although with increasing human or live-stock-related disturbance, gazelle maintained a reduced distance to the source of the disturbance. Presumably owing to that shift, movement costs were more important as disturbance increased. In addition, Mongolian gazelle selected habitats based on topographical features promoting greater visibility where disturbance was lower. We suggest several management
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A guide to calculating habitat-quality metrics to inform conservation of highly mobile species
Bieri, Joanna A.; Sample, Christine; Thogmartin, Wayne E.; Diffendorfer, James E.; Earl, Julia E.; Erickson, Richard A.; Federico, Paula; Flockhart, D. T. Tyler; Nicol, Sam; Semmens, Darius J.; Skraber, T.; Wiederholt, Ruscena; Mattsson, Brady J.
2018-01-01
Many metrics exist for quantifying the relative value of habitats and pathways used by highly mobile species. Properly selecting and applying such metrics requires substantial background in mathematics and understanding the relevant management arena. To address this multidimensional challenge, we demonstrate and compare three measurements of habitat quality: graph-, occupancy-, and demographic-based metrics. Each metric provides insights into system dynamics, at the expense of increasing amounts and complexity of data and models. Our descriptions and comparisons of diverse habitat-quality metrics provide means for practitioners to overcome the modeling challenges associated with management or conservation of such highly mobile species. Whereas previous guidance for applying habitat-quality metrics has been scattered in diversified tracks of literature, we have brought this information together into an approachable format including accessible descriptions and a modeling case study for a typical example that conservation professionals can adapt for their own decision contexts and focal populations.Considerations for Resource ManagersManagement objectives, proposed actions, data availability and quality, and model assumptions are all relevant considerations when applying and interpreting habitat-quality metrics.Graph-based metrics answer questions related to habitat centrality and connectivity, are suitable for populations with any movement pattern, quantify basic spatial and temporal patterns of occupancy and movement, and require the least data.Occupancy-based metrics answer questions about likelihood of persistence or colonization, are suitable for populations that undergo localized extinctions, quantify spatial and temporal patterns of occupancy and movement, and require a moderate amount of data.Demographic-based metrics answer questions about relative or absolute population size, are suitable for populations with any movement pattern, quantify demographic
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Viña, Andrés; Bearer, Scott; Chen, Xiaodong; He, Guangming; Linderman, Marc; An, Li; Zhang, Hemin; Ouyang, Zhiyun; Liu, Jianguo
2007-06-01
Global biodiversity loss is largely driven by human activities such as the conversion of natural to human-dominated landscapes. A popular approach to mitigating land cover change is the designation of protected areas (e.g., nature reserves). Nature reserves are traditionally perceived as strongholds of biodiversity conservation. However, many reserves are affected by land cover changes not only within their boundaries, but also in their surrounding areas. This study analyzed the changes in habitat for the giant panda (Ailuropoda melanoleuca) inside Wolong Nature Reserve, Sichuan, China, and in a 3-km buffer area outside its boundaries, through a time series of classified satellite imagery and field observations. Habitat connectivity between the inside and the outside of the reserve diminished between 1965 and 2001 because panda habitat was steadily lost both inside and outside the reserve. However, habitat connectivity slightly increased between 1997 and 2001 due to the stabilization of some panda habitat inside and outside the reserve. This stabilization most likely occurred as a response to changes in socioeconomic activities (e.g., shifts from agricultural to nonagricultural economies). Recently implemented government policies could further mitigate the impacts of land cover change on panda habitat. The results suggest that Wolong Nature Reserve, and perhaps other nature reserves in other parts of the world, cannot be managed as an isolated entity because habitat connectivity declines with land cover changes outside the reserve even if the area inside the reserve is well protected. The findings and approaches presented in this paper may also have important implications for the management of other nature reserves across the world.
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C. Kerry Overton; Michael A. Radko; Rodger L. Nelson
1993-01-01
Differences in fish habitat variables between two studied watersheds may be related to differences in land management. In using the R1/R4 Watershed-Scale Fish Habitat Inventory Process, for most habitat variables, evaluations of sample sizes of at least 30 habitat units were adequate. Guidelines will help land managers in determining sample sizes required to detect...
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HABITAT ASSESSMENT MODELS FOR BAY SCALLOP, ARGOPECTEN IRRADIANS
Bay scallops (Argopecten irradians) inhabit shallow subtidal habitats along the Atlantic coast of the United States and require settlement substrates, such as submerged aquatic vegetation (SAV), for their early juvenile stages. The short lifespan of bay scallops (1-2 yr) coupled...
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EXAMINING ASSOCIATIONS BETWEEN FISH ASSEMBLAGES AND PHYSICAL HABITAT
Assessing lotic fish-habitat interactions from regional survey data requires that we consider a comprehensive representation, at the appropriate scale, of the likely controls on fish assemblages. At the scale of stream and river reaches, the important dimensions of physical habi...
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Null expectations for disease dynamics in shrinking habitat: dilution or amplification?
McCallum, Hamish I.; Gillespie, Thomas R.
2017-01-01
As biodiversity declines with anthropogenic land-use change, it is increasingly important to understand how changing biodiversity affects infectious disease risk. The dilution effect hypothesis, which points to decreases in biodiversity as critical to an increase in infection risk, has received considerable attention due to the allure of a win–win scenario for conservation and human well-being. Yet some empirical data suggest that the dilution effect is not a generalizable phenomenon. We explore the response of pathogen transmission dynamics to changes in biodiversity that are driven by habitat loss using an allometrically scaled multi-host model. With this model, we show that declining habitat, and thus declining biodiversity, can lead to either increasing or decreasing infectious-disease risk, measured as endemic prevalence. Whether larger habitats, and thus greater biodiversity, lead to a decrease (dilution effect) or increase (amplification effect) in infection prevalence depends upon the pathogen transmission mode and how host competence scales with body size. Dilution effects were detected for most frequency-transmitted pathogens and amplification effects were detected for density-dependent pathogens. Amplification effects were also observed over a particular range of habitat loss in frequency-dependent pathogens when we assumed that host competence was greatest in large-bodied species. By contrast, only amplification effects were observed for density-dependent pathogens; host competency only affected the magnitude of the effect. These models can be used to guide future empirical studies of biodiversity–disease relationships across gradients of habitat loss. The type of transmission, the relationship between host competence and community assembly, the identity of hosts contributing to transmission, and how transmission scales with area are essential factors to consider when elucidating the mechanisms driving disease risk in shrinking habitat. This article
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Null expectations for disease dynamics in shrinking habitat: dilution or amplification?
Faust, Christina L; Dobson, Andrew P; Gottdenker, Nicole; Bloomfield, Laura S P; McCallum, Hamish I; Gillespie, Thomas R; Diuk-Wasser, Maria; Plowright, Raina K
2017-06-05
As biodiversity declines with anthropogenic land-use change, it is increasingly important to understand how changing biodiversity affects infectious disease risk. The dilution effect hypothesis, which points to decreases in biodiversity as critical to an increase in infection risk, has received considerable attention due to the allure of a win-win scenario for conservation and human well-being. Yet some empirical data suggest that the dilution effect is not a generalizable phenomenon. We explore the response of pathogen transmission dynamics to changes in biodiversity that are driven by habitat loss using an allometrically scaled multi-host model. With this model, we show that declining habitat, and thus declining biodiversity, can lead to either increasing or decreasing infectious-disease risk, measured as endemic prevalence. Whether larger habitats, and thus greater biodiversity, lead to a decrease (dilution effect) or increase (amplification effect) in infection prevalence depends upon the pathogen transmission mode and how host competence scales with body size. Dilution effects were detected for most frequency-transmitted pathogens and amplification effects were detected for density-dependent pathogens. Amplification effects were also observed over a particular range of habitat loss in frequency-dependent pathogens when we assumed that host competence was greatest in large-bodied species. By contrast, only amplification effects were observed for density-dependent pathogens; host competency only affected the magnitude of the effect. These models can be used to guide future empirical studies of biodiversity-disease relationships across gradients of habitat loss. The type of transmission, the relationship between host competence and community assembly, the identity of hosts contributing to transmission, and how transmission scales with area are essential factors to consider when elucidating the mechanisms driving disease risk in shrinking habitat.This article is
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Keller, Daniel L; Laub, Brian G; Birdsey, Paul; Dean, David J
2014-09-01
Tamarisk removal is a widespread restoration practice on rivers in the southwestern USA, but impacts of removal on fish habitat have rarely been investigated. We examined whether tamarisk removal, in combination with a large spring flood, had the potential to improve fish habitat on the San Rafael River in southeastern Utah. We quantified habitat complexity and the distribution of wood accumulation in a tamarisk removal site (treated) and a non-removal site (untreated) in 2010, 1 year prior to a large magnitude and long-duration spring flood. We used aerial imagery to analyze river changes in the treated and untreated sites. Areas of channel movement were significantly larger in the treated site compared to the untreated site, primarily because of geomorphic characteristics of the channel, including higher sinuosity and the presence of an ephemeral tributary. However, results suggest that tamarisk removal on the outside of meander bends, where it grows directly on the channel margins, can promote increased channel movement. Prior to the flood, wood accumulations were concentrated in sections of channel where tamarisk had been removed. Pools, riffles, and backwaters occurred more frequently within 30 m upstream and downstream of wood accumulations compared to areas within 30 m of random points. Pools associated with wood accumulations were also significantly larger and deeper than those associated with random points. These results suggest that the combination of tamarisk removal and wood input can increase the potential for channel movement during spring floods thereby diversifying river habitat and improving conditions for native fish.
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NASA Astrophysics Data System (ADS)
Keller, Daniel L.; Laub, Brian G.; Birdsey, Paul; Dean, David J.
2014-09-01
Tamarisk removal is a widespread restoration practice on rivers in the southwestern USA, but impacts of removal on fish habitat have rarely been investigated. We examined whether tamarisk removal, in combination with a large spring flood, had the potential to improve fish habitat on the San Rafael River in southeastern Utah. We quantified habitat complexity and the distribution of wood accumulation in a tamarisk removal site (treated) and a non-removal site (untreated) in 2010, 1 year prior to a large magnitude and long-duration spring flood. We used aerial imagery to analyze river changes in the treated and untreated sites. Areas of channel movement were significantly larger in the treated site compared to the untreated site, primarily because of geomorphic characteristics of the channel, including higher sinuosity and the presence of an ephemeral tributary. However, results suggest that tamarisk removal on the outside of meander bends, where it grows directly on the channel margins, can promote increased channel movement. Prior to the flood, wood accumulations were concentrated in sections of channel where tamarisk had been removed. Pools, riffles, and backwaters occurred more frequently within 30 m upstream and downstream of wood accumulations compared to areas within 30 m of random points. Pools associated with wood accumulations were also significantly larger and deeper than those associated with random points. These results suggest that the combination of tamarisk removal and wood input can increase the potential for channel movement during spring floods thereby diversifying river habitat and improving conditions for native fish.
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K. M. Slauson; W. J. Zielinski
2009-01-01
American martens use resting habitat between periods of activity to provide both thermal refugia and protection from predators. Maintenance or restoration of key elements of marten resting habitat, such as resting structures, requires that managers recognize their characteristics to protect them, or manage for their creation. We measured resting habitat at 4 scales: (1...
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Ord's kangaroo rats living in floodplain habitats: Factors contributing to habitat attraction
Miller, M.S.; Wilson, K.R.; Andersen, D.C.
2003-01-01
High densities of an aridland granivore, Ord's kangaroo rat (Dipodomys ordii), have been documented in floodplain habitats along the Yampa River in northwestern Colorado. Despite a high probability of inundation and attendant high mortality during the spring flood period, the habitat is consistently recolonized. To understand factors that potentially make riparian habitats attractive to D. ordii, we compared density and spatial pattern of seeds, density of a competitor (western harvester ant, Pogonomyrmex occidentalis), and digging energetics within floodplain habitats and between floodplain and adjacent upland habitats. Seed density within the floodplain was greatest in the topographically high (rarely flooded) floodplain and lowest immediately after a spring flood in the topographically low (frequently flooded) floodplain. Seed densities in adjacent upland habitat that never floods were higher than the lowest floodplain habitat. In the low floodplain prior to flooding, seeds had a clumped spatial pattern, which D. ordii is adept at exploiting; after spring flooding, a more random pattern resulted. Populations of the western harvester ant were low in the floodplain relative to the upland. Digging by D. ordii was energetically less expensive in floodplain areas than in upland areas. Despite the potential for mortality due to annual spring flooding, the combination of less competition from harvester ants and lower energetic costs of digging might promote the use of floodplain habitat by D. ordii.
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Habitat use by giant panda in relation to man-made forest in Wanglang Nature Reserve of China.
Kang, Dongwei; Wang, Xiaorong; Yang, Hongwei; Duan, Lijuan; Li, Junqing
2014-12-01
To evaluate the effectiveness of human restoration in species conservation, in this study, we undertook a field survey of giant panda (Ailuropoda melanoleuca) habitat and man-made forest habitat in Wanglang Nature Reserve of China. Our results revealed that giant panda did not use the man-made forest in this area so far, and that there were significant differences between the giant panda habitat and the man-made forest habitat. Compared with giant panda habitat, the man-made forest habitat was characterized by lower shrub coverage, thinner trees and lower bamboo density. To improve the effectiveness of human restoration, the habitat requirement of giant panda should be fully consider in the whole process of habitat restoration.
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The Habitat Demonstration Unit Project Overview
NASA Technical Reports Server (NTRS)
Kennedy, Kriss J.; Grill, Tracy R.; Tri, Terry O.; Howe, Alan S.
2010-01-01
This paper will describe an overview of the National Aeronautics and Space Administration (NASA) led multi-center Habitat Demonstration Unit (HDU) Project. The HDU project is a "technology-pull" project that integrates technologies and innovations from numerous NASA centers. This project will be used to investigate and validate surface architectures, operations concepts, and requirements definition of various habitation concepts. The first habitation configuration this project will build and test is the Pressurized Excursion Module (PEM). This habitat configuration - the PEM - is based on the Constellation Architecture Scenario 12.1 concept of a vertically oriented habitat module. The HDU project will be tested as part of the 2010 Desert Research and Technologies Simulations (D-RATS) test objectives. The purpose of this project is to develop, integrate, test, and evaluate a habitat configuration in the context of the mission architectures and surface operation concepts. A multi-center approach will be leveraged to build, integrate, and test the PEM through a shared collaborative effort of multiple NASA centers. The HDU project is part of the strategic plan from the Exploration Systems Mission Directorate (ESMD) Directorate Integration Office (DIO) and the Lunar Surface Systems Project Office (LSSPO) to test surface elements in a surface analog environment. The 2010 analog field test will include two Lunar Electric Rovers (LER) and the PEM among other surface demonstration elements. This paper will describe the overall objectives, its various habitat configurations, strategic plan, and technology integration as it pertains to the 2010 and 2011 field analog tests. To accomplish the development of the PEM from conception in June 2009 to rollout for operations in July 2010, the HDU project team is using a set of design standards to define the interfaces between the various systems of PEM and to the payloads, such as the Geology Lab, that those systems will support
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Jang, Gijeong; Yoon, Shin-ae; Lee, Sung-Eun; Park, Haeil; Kim, Joohan; Ko, Jeong Hoon; Park, Hae-Jeong
2013-11-01
In ordinary conversations, literal meanings of an utterance are often quite different from implicated meanings and the inference about implicated meanings is essentially required for successful comprehension of the speaker's utterances. Inference of finding implicated meanings is based on the listener's assumption that the conversational partner says only relevant matters according to the maxim of relevance in Grice's theory of conversational implicature. To investigate the neural correlates of comprehending implicated meanings under the maxim of relevance, a total of 23 participants underwent an fMRI task with a series of conversational pairs, each consisting of a question and an answer. The experimental paradigm was composed of three conditions: explicit answers, moderately implicit answers, and highly implicit answers. Participants were asked to decide whether the answer to the Yes/No question meant 'Yes' or 'No'. Longer reaction time was required for the highly implicit answers than for the moderately implicit answers without affecting the accuracy. The fMRI results show that the left anterior temporal lobe, left angular gyrus, and left posterior middle temporal gyrus had stronger activation in both moderately and highly implicit conditions than in the explicit condition. Comprehension of highly implicit answers had increased activations in additional regions including the left inferior frontal gyrus, left medial prefrontal cortex, left posterior cingulate cortex and right anterior temporal lobe. The activation results indicate involvement of these regions in the inference process to build coherence between literally irrelevant but pragmatically associated utterances under the maxim of relevance. Especially, the left anterior temporal lobe showed high sensitivity to the level of implicitness and showed increased activation for highly versus moderately implicit conditions, which imply its central role in inference such as semantic integration. The right
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Global climate change and sea level rise: potential losses of intertidal habitat for shorebirds
H. Galbraith; R. Jones; R. Park; J. Clough; S. Herrod-Julius; B. Harrington; G. Page
2005-01-01
Global warming is expected to result in an acceleration of current rates of sea level rise, inundating many low-lying coastal and intertidal areas. This could have important implications for organisms that depend on these sites, including shorebirds that rely on them for foraging habitat during their migrations and in winter. We modeled the potential changes in the...
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A habitat assessment for Florida panther population expansion into central Florida
Thatcher, C.A.; Van Manen, F.T.; Clark, J.D.
2009-01-01
One of the goals of the Florida panther (Puma concolor coryi) recovery plan is to expand panther range north of the Caloosahatchee River in central Florida. Our objective was to evaluate the potential of that region to support panthers. We used a geographic information system and the Mahalanobis distance statistic to develop a habitat model based on landscape characteristics associated with panther home ranges. We used cross-validation and an independent telemetry data set to test the habitat model. We also conducted a least-cost path analysis to identify potential habitat linkages and to provide a relative measure of connectivity among habitat patches. Variables in our model were paved road density, major highways, human population density, percentage of the area permanently or semipermanently flooded, and percentage of the area in natural land cover. Our model clearly identified habitat typical of that found within panther home ranges based on model testing with recent telemetry data. We identified 4 potential translocation sites that may support a total of approximately 36 panthers. Although we identified potential habitat linkages, our least-cost path analyses highlighted the extreme isolation of panther habitat in portions of the study area. Human intervention will likely be required if the goal is to establish female panthers north of the Caloosahatchee in the near term.
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Habitat structure mediates biodiversity effects on ecosystem properties
Godbold, J. A.; Bulling, M. T.; Solan, M.
2011-01-01
Much of what we know about the role of biodiversity in mediating ecosystem processes and function stems from manipulative experiments, which have largely been performed in isolated, homogeneous environments that do not incorporate habitat structure or allow natural community dynamics to develop. Here, we use a range of habitat configurations in a model marine benthic system to investigate the effects of species composition, resource heterogeneity and patch connectivity on ecosystem properties at both the patch (bioturbation intensity) and multi-patch (nutrient concentration) scale. We show that allowing fauna to move and preferentially select patches alters local species composition and density distributions, which has negative effects on ecosystem processes (bioturbation intensity) at the patch scale, but overall positive effects on ecosystem functioning (nutrient concentration) at the multi-patch scale. Our findings provide important evidence that community dynamics alter in response to localized resource heterogeneity and that these small-scale variations in habitat structure influence species contributions to ecosystem properties at larger scales. We conclude that habitat complexity forms an important buffer against disturbance and that contemporary estimates of the level of biodiversity required for maintaining future multi-functional systems may need to be revised. PMID:21227969
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Habitat structure mediates biodiversity effects on ecosystem properties.
Godbold, J A; Bulling, M T; Solan, M
2011-08-22
Much of what we know about the role of biodiversity in mediating ecosystem processes and function stems from manipulative experiments, which have largely been performed in isolated, homogeneous environments that do not incorporate habitat structure or allow natural community dynamics to develop. Here, we use a range of habitat configurations in a model marine benthic system to investigate the effects of species composition, resource heterogeneity and patch connectivity on ecosystem properties at both the patch (bioturbation intensity) and multi-patch (nutrient concentration) scale. We show that allowing fauna to move and preferentially select patches alters local species composition and density distributions, which has negative effects on ecosystem processes (bioturbation intensity) at the patch scale, but overall positive effects on ecosystem functioning (nutrient concentration) at the multi-patch scale. Our findings provide important evidence that community dynamics alter in response to localized resource heterogeneity and that these small-scale variations in habitat structure influence species contributions to ecosystem properties at larger scales. We conclude that habitat complexity forms an important buffer against disturbance and that contemporary estimates of the level of biodiversity required for maintaining future multi-functional systems may need to be revised.
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Strategies for monitoring terrestrial animals and habitats
Richard Holthausen; Raymond L. Czaplewski; Don DeLorenzo; Greg Hayward; Winifred B. Kessler; Pat Manley; Kevin S. McKelvey; Douglas S. Powell; Leonard F. Ruggiero; Michael K. Schwartz; Bea Van Horne; Christina D. Vojta
2005-01-01
This General Technical Report (GTR) addresses monitoring strategies for terrestrial animals and habitats. It focuses on monitoring associated with National Forest Management Act planning and is intended to apply primarily to monitoring efforts that are broader than individual National Forests. Primary topics covered in the GTR are monitoring requirements; ongoing...
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Fort Collins Science Center: Species and Habitats of Federal Interest
Stevens, Patty
2004-01-01
Ecosystem changes directly affect a wide variety of plant and animal species, floral and faunal communities, and groups of species such as amphibians and grassland birds. Appropriate management of public lands plays a crucial role in the conservation and recovery of endangered species and can be a key element in preventing a species from being listed under the Endangered Species Act. The Species and Habitats of Federal Interest Branch of the Fort Collins Science Center (FORT) conducts research on the ecology, habitat requirements, distribution and abundance, population dynamics, and genetics and systematics of many species facing threatened or endangered status or of special concern to resource management agencies. FORT scientists develop reintroduction and restoration techniques, technologies for monitoring populations, and novel methods to analyze data on population trends and habitat requirements. FORT expertise encompasses both traditional and specialized natural resource disciplines within wildlife biology, including population dynamics, animal behavior, plant and community ecology, inventory and monitoring, statistics and computer applications, conservation genetics, stable isotope analysis, and curatorial expertise.
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NASA Technical Reports Server (NTRS)
Ganapathi, Gani B.; Ferrall, Joseph; Seshan, P. K.
1993-01-01
A survey of distinct conceptual lunar habitat designs covering the pre- and post-Apollo era is presented. The impact of the significant lunar environmental challenges such as temperature, atmosphere, radiation, soil properties, meteorites, and seismic activity on the habitat design parameters are outlined. Over twenty habitat designs were identified and classified according to mission type, crew size; total duration of stay, modularity, environmental protection measures, and emplacement. Simple selection criteria of (1) post-Apollo design, (2) uniqueness of the habitat design, (3) level of thoroughness in design layout, (4) habitat dimensions are provided, and (5) materials of construction for the habitat shell are specified, are used to select five habitats for future trade studies. Habitat emplacement scenarios are created to examine the possible impact of emplacement of the habitat in different locations, such as lunar poles vs. equatorial, above ground vs. below ground, etc.
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Matchett, Elliott L.; Fleskes, Joseph P.; Young, Charles A.; Purkey, David R.
2015-01-01
The amount and quality of natural resources available for terrestrial and aquatic wildlife habitats are expected to decrease throughout the world in areas that are intensively managed for urban and agricultural uses. Changes in climate and management of increasingly limited water supplies may further impact water resources essential for sustaining habitats. In this report, we document adapting a Water Evaluation and Planning (WEAP) system model for the Central Valley of California. We demonstrate using this adapted model (WEAP-CVwh) to evaluate impacts produced from plausible future scenarios on agricultural and wetland habitats used by waterbirds and other wildlife. Processed output from WEAP-CVwh indicated varying levels of impact caused by projected climate, urbanization, and water supply management in scenarios used to exemplify this approach. Among scenarios, the NCAR-CCSM3 A2 climate projection had a greater impact than the CNRM-CM3 B1 climate projection, whereas expansive urbanization had a greater impact than strategic urbanization, on annual availability of waterbird habitat. Scenarios including extensive rice-idling or substantial instream flow requirements on important water supply sources produced large impacts on annual availability of waterbird habitat. In the year corresponding with the greatest habitat reduction for each scenario, the scenario including instream flow requirements resulted in the greatest decrease in habitats throughout all months of the wintering period relative to other scenarios. This approach provides a new and useful tool for habitat conservation planning in the Central Valley and a model to guide similar research investigations aiming to inform conservation, management, and restoration of important wildlife habitats.
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Arc Habitat Suitability Index computer software
Thomas M. Juntti; Mark A. Rumble
2006-01-01
This user manual describes the Arc Habitat Suitability Index (ArcHSI), which is a geographical information system (GIS) model that estimates the ability of an area to meet the food and cover requirements of an animal species. The components and parameters of the model occur in tables and can be easily edited or otherwise modified. ArcHSI runs on personal computers with...
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Wildlife habitats and biological diversity in the Rocky Mountains and Northern Great Plains
Deborah M. Finch; Leonard F. Ruggiero
1993-01-01
We identify wetlands, riparian woodlands and shrublands, green ash woodlands, aspen forests, pinyon-juniper woodlands, and pure and mixed forests of ponderosa pine as important wildlife habitats in the US. Forest Service's Rocky Mountain Region. The relationships of vertebrate species to each of these types are discussed relative to habitat requirements and...
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Constellation Architecture Team-Lunar: Lunar Habitat Concepts
NASA Technical Reports Server (NTRS)
Toups, Larry; Kennedy, Kriss J.
2008-01-01
This paper will describe lunar habitat concepts that were defined as part of the Constellation Architecture Team-Lunar (CxAT-Lunar) in support of the Vision for Space Exploration. There are many challenges to designing lunar habitats such as mission objectives, launch packaging, lander capability, and risks. Surface habitats are required in support of sustaining human life to meet the mission objectives of lunar exploration, operations, and sustainability. Lunar surface operations consist of crew operations, mission operations, EVA operations, science operations, and logistics operations. Habitats are crewed pressurized vessels that include surface mission operations, science laboratories, living support capabilities, EVA support, logistics, and maintenance facilities. The challenge is to deliver, unload, and deploy self-contained habitats and laboratories to the lunar surface. The CxAT-Lunar surface campaign analysis focused on three primary trade sets of analysis. Trade set one (TS1) investigated sustaining a crew of four for six months with full outpost capability and the ability to perform long surface mission excursions using large mobility systems. Two basic habitat concepts of a hard metallic horizontal cylinder and a larger inflatable torus concept were investigated as options in response to the surface exploration architecture campaign analysis. Figure 1 and 2 depicts the notional outpost configurations for this trade set. Trade set two (TS2) investigated a mobile architecture approach with the campaign focused on early exploration using two small pressurized rovers and a mobile logistics support capability. This exploration concept will not be described in this paper. Trade set three (TS3) investigated delivery of a "core' habitation capability in support of an early outpost that would mature into the TS1 full outpost capability. Three core habitat concepts were defined for this campaign analysis. One with a four port core habitat, another with a 2 port
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Boykin, K.G.; Thompson, B.C.; Propeck-Gray, S.
2010-01-01
Despite widespread and long-standing efforts to model wildlife-habitat associations using remotely sensed and other spatially explicit data, there are relatively few evaluations of the performance of variables included in predictive models relative to actual features on the landscape. As part of the National Gap Analysis Program, we specifically examined physical site features at randomly selected sample locations in the Southwestern U.S. to assess degree of concordance with predicted features used in modeling vertebrate habitat distribution. Our analysis considered hypotheses about relative accuracy with respect to 30 vertebrate species selected to represent the spectrum of habitat generalist to specialist and categorization of site by relative degree of conservation emphasis accorded to the site. Overall comparison of 19 variables observed at 382 sample sites indicated ???60% concordance for 12 variables. Directly measured or observed variables (slope, soil composition, rock outcrop) generally displayed high concordance, while variables that required judgments regarding descriptive categories (aspect, ecological system, landform) were less concordant. There were no differences detected in concordance among taxa groups, degree of specialization or generalization of selected taxa, or land conservation categorization of sample sites with respect to all sites. We found no support for the hypothesis that accuracy of habitat models is inversely related to degree of taxa specialization when model features for a habitat specialist could be more difficult to represent spatially. Likewise, we did not find support for the hypothesis that physical features will be predicted with higher accuracy on lands with greater dedication to biodiversity conservation than on other lands because of relative differences regarding available information. Accuracy generally was similar (>60%) to that observed for land cover mapping at the ecological system level. These patterns demonstrate
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T.A. Hanley; C.T. Robbins; D.E. Spalinger
1989-01-01
Research on forest habitats and the nutritional ecology of Sitka black-tailed deer conducted during 1981 through 1986 is reviewed and synthesized. The research approach was based on the assumption that foraging efficiency is the best single measure of habitat quality for an individual deer. Overstory-understory relations and the influence of forest overstory on snow...
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Projected trends in forest habitat classes under climate and land-use change scenarios
Brian G. Tavernia; Mark D. Nelson; Brian F. Walters; Chris Toney
2012-01-01
Wildlife species have diverse and sometimes conflicting habitat requirements. To support diverse wildlife communities, natural resource managers need to manage for a variety of habitats across a large area and to create long-term management plans to ensure this variety is maintained. In these efforts, managers would benefit from assessments of potential climate and...
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NASA Technical Reports Server (NTRS)
Martin, Rodney A.
2017-01-01
Habitation systems provide a safe place for astronauts to live and work in space and on planetary surfaces. They enable crews to live and work safely in deep space, and include integrated life support systems, radiation protection, fire safety, and systems to reduce logistics and the need for resupply missions. Innovative health management technologies are needed in order to increase the safety and mission-effectiveness for future space habitats on other planets, asteroids, or lunar surfaces. For example, off-nominal or failure conditions occurring in safety-critical life support systems may need to be addressed quickly by the habitat crew without extensive technical support from Earth due to communication delays. If the crew in the habitat must manage, plan and operate much of the mission themselves, operations support must be migrated from Earth to the habitat. Enabling monitoring, tracking, and management capabilities on-board the habitat and related EVA platforms for a small crew to use will require significant automation and decision support software.Traditional caution and warning systems are typically triggered by out-of-bounds sensor values, but can be enhanced by including machine learning and data mining techniques. These methods aim to reveal latent, unknown conditions while still retaining and improving the ability to provide highly accurate alerts for known issues. A few of these techniques will briefly described, along with performance targets for known faults and failures. Specific system health management capabilities required for habitat system elements (environmental control and life support systems, etc.) may include relevant subsystems such as water recycling systems, photovoltaic systems, electrical power systems, and environmental monitoring systems. Sustainability Base, the agency's flagship LEED-platinum certified green building acts as a living laboratory for testing advanced information and sustainable technologies that provides an
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Habitat preferences of baleen whales in a mid-latitude habitat
NASA Astrophysics Data System (ADS)
Prieto, Rui; Tobeña, Marta; Silva, Mónica A.
2017-07-01
Understanding the dynamics of baleen whale distribution is essential to predict how environmental changes can affect their ecology and, in turn, ecosystem functioning. Recent work showed that mid-latitude habitats along migratory routes may play an important role on the feeding ecology of baleen whales. This study aimed to investigate the function of a mid-latitude habitat for blue (Balaenoptera musculus), fin (Balaenoptera physalus) and sei (Balaenoptera borealis) whales occurring in sympatry during spring and summer months and to what extent their environmental niches overlap. We addressed those questions by developing environmental niche models (ENM) for each species and then making pairwise comparisons of niche overlap and relative habitat patch importance among the three species. ENMs were created using sightings from the Azorean Fisheries Observer Program from May to November, between 2004 and 2009, and a set of 18 predictor environmental variables. We then assessed monthly (April-July) overlap among ENMs using a modified Hellinger's distance metric (I). Results show that the habitat niches of blue and fin whales are strongly influenced by primary productivity and sea surface temperature and are highly dynamic both spatially and temporally due to the oceanography of the region. Niche overlap analyses show that blue and fin whale environmental niches are similar and that the suitable habitats for the two species have high degree of spatial coincidence. These results in combination suggest that this habitat may function as a mid-latitude feeding ground to both species while conditions are adequate. The sei whale model, on the other hand, did not include variables considered to be proxies for prey distribution and little environmental niche overlap was found between this species and the other two. We argue that these results suggest that the region holds little importance as a foraging habitat for the sei whale.
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Wildlife habitats in managed rangelands—the Great Basin of southeastern Oregon: manmade habitats.
Chris Maser; Jack Ward Thomas; Ira David Luman; Ralph. Anderson
1979-01-01
Manmade structures on rangelands provide specialized habitats for some species. These habitats and how they function as specialized habitat features are examined in this publication. The relationships of the wildlife of the Great Basin to such structures are detailed.
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Labbe, Michelle A.; King, David I.
2014-01-01
Many species of mature forest-nesting birds (“forest birds”) undergo a pronounced shift in habitat use during the post-fledging period and move from their forest nesting sites into areas of early-successional vegetation. Mortality is high during this period, thus understanding the resource requirements of post-fledging birds has implications for conservation. Efforts to identify predictors of abundance of forest birds in patches of early-successional habitats have so far been equivocal, yet these previous studies have primarily focused on contiguously forested landscapes and the potential for landscape-scale influences in more fragmented and modified landscapes is largely unknown. Landscape composition can have a strong influence on the abundance and productivity of forest birds during the nesting period, and could therefore affect the number of forest birds in the landscape available to colonize early-successional habitats during the post-fledging period. Therefore, the inclusion of landscape characteristics should increase the explanatory power of models of forest bird abundance in early-successional habitat patches during the post-fledging period. We examined forest bird abundance and body condition in relation to landscape and habitat characteristics of 15 early-successional sites during the post-fledging season in Massachusetts. The abundance of forest birds was influenced by within-patch habitat characteristics, however the explanatory power of these models was significantly increased by the inclusion of landscape fragmentation and the abundance of forest birds in adjacent forest during the nesting period for some species and age groups. Our findings show that including factors beyond the patch scale can explain additional variation in the abundance of forest birds in early-successional habitats during the post-fledging period. We conclude that landscape composition should be considered when siting early-successional habitat to maximize its benefit to
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Labbe, Michelle A; King, David I
2014-01-01
Many species of mature forest-nesting birds ("forest birds") undergo a pronounced shift in habitat use during the post-fledging period and move from their forest nesting sites into areas of early-successional vegetation. Mortality is high during this period, thus understanding the resource requirements of post-fledging birds has implications for conservation. Efforts to identify predictors of abundance of forest birds in patches of early-successional habitats have so far been equivocal, yet these previous studies have primarily focused on contiguously forested landscapes and the potential for landscape-scale influences in more fragmented and modified landscapes is largely unknown. Landscape composition can have a strong influence on the abundance and productivity of forest birds during the nesting period, and could therefore affect the number of forest birds in the landscape available to colonize early-successional habitats during the post-fledging period. Therefore, the inclusion of landscape characteristics should increase the explanatory power of models of forest bird abundance in early-successional habitat patches during the post-fledging period. We examined forest bird abundance and body condition in relation to landscape and habitat characteristics of 15 early-successional sites during the post-fledging season in Massachusetts. The abundance of forest birds was influenced by within-patch habitat characteristics, however the explanatory power of these models was significantly increased by the inclusion of landscape fragmentation and the abundance of forest birds in adjacent forest during the nesting period for some species and age groups. Our findings show that including factors beyond the patch scale can explain additional variation in the abundance of forest birds in early-successional habitats during the post-fledging period. We conclude that landscape composition should be considered when siting early-successional habitat to maximize its benefit to forest
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Unionid habitat and assemblage composition in coastal plain tributaries of the Flint River (Georgia)
Gagnon, P.; Michener, W.; Freeman, M.; Brim-Box, J.
2006-01-01
Effective conservation of mussels in streams of the lower Flint River basin, southwest Georgia, requires more rigorous understanding of mussel-habitat associations and factors shaping assemblage composition in stream reaches. We surveyed mussels and habitat conditions at 46 locations, and used regression, correlation and multivariate direct gradient analysis (Canonical Correspondence Analyses) to identify species-habitat relationships and characteristic species-assemblage types in Flint basin streams. Riparian wetland and catchment forest cover, average mid-channel depth, and drainage network position accounted for 49% of the variability in mussel species richness, 36% of the variability in unionid abundance, and 32% of the variability observed in Shannon-Wiener diversity across survey sites. Species were grouped into four assemblage types based on their habitat associations: large-river-riffle associates, slackwater associates, habitat generalists, and stream-run associates. Results are broadly concordant with anecdotal reports of mussel-habitat relationships and provide insight into the habitat conservation needs of mussels.
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Local-scale habitat associations of grassland birds in southwestern Minnesota
Elliott, Lisa H.; Johnson, Douglas H.
2017-01-01
Conservation of obligate grassland species requires not only the protection of a sufficiently large area of habitat but also the availability of necessary vegetation characteristics for particular species. As a result land managers must understand which habitat characteristics are important for their target species. To identify the habitat associations of eight species of grassland birds, we conducted bird and vegetation surveys on 66 grassland habitat patches in southwestern Minnesota in 2013 and 2014. Species of interest included sedge wren (Cistothorus platensis), Savannah sparrow (Passerculus sandwichensis), grasshopper sparrow (Ammodramus savannarum), Henslow's sparrow (Ammodramus henslowii), dickcissel (Spiza americana), bobolink (Dolichonyx oryzivorus), and western meadowlark (Sturnella neglecta). We calculated correlation coefficients between vegetation variables and species density as measures of linear association. We assessed curvilinear relationships with loess plots. We found grassland birds on 95.5% of surveyed sites, indicating remnant prairie in southwestern Minnesota is used by grassland birds. In general individual species showed different patterns of association and most species were tolerant of a wide variety of habitat conditions. The most consistent pattern was a negative association with both the quantity and proximity of trees. Our findings that individual species have different habitat preferences suggest that prairie resource managers may need to coordinate management efforts in order to create a mosaic of habitat types to support multiple species, though tree control will be an important and ongoing management activity at the individual site level.
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Detroit River habitat inventory
Manny, Bruce A.
2003-01-01
This inventory complements a previous survey of habitat in Ontario waters of the Detroit River (OMNR,1993). It is a starting point for balanced and sustained use of the river for natural resource conservation and economic development. The objectives of the inventory were to: (1) locate candidate sites for protection and restoration of fish and wildlife habitat in Michigan waters of the Detroit River; (2) describe the ownership and size of each site, as well as its potential for habitat protection and restoration; and (3) subjectively assess the extent to which existing habitat along the river is productive of fish and wildlife and protected from land uses that have degraded or destroyed such habitat.
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Pearson, Scott F.; Knapp, Shannon M.
2016-01-01
Habitat selection that has fitness consequences has important implications for conservation activities. For example, habitat characteristics that influence nest success in birds can be manipulated to improve habitat quality with the goal of ultimately improving reproductive success. We examined habitat selection by the threatened streaked horned lark (Eremophila alpestris strigata) at both the breeding-site (territory) and nest-site scales. Larks were selective at both spatial scales but with contrasting selection. At the territory scale, male larks selected sparsely vegetated grasslands with relatively short vegetation. At the nest-site scale, female larks selected sites within territories with higher vegetation density and more perennial forbs. These nest-site scale choices had reproductive consequences, with greater nest success in areas with higher densities of perennial forbs. We experimentally manipulated lark habitat structure in an attempt to mimic the habitat conditions selected by larks by using late summer prescribed fires. After the burn, changes in vegetation structure were in the direction preferred by larks but habitat effects attenuated by the following year. Our results highlight the importance of evaluating habitat selection at spatial scales appropriate to the species of interest, especially when attempting to improve habitat quality for rare and declining species. They also highlight the importance of conducting restoration activities in a research context. For example, because the sparsely vegetated conditions created by fire attenuate, there may be value in examining more frequent burns or hotter fires as the next management and research action. We hope the design outlined in this study will serve as an integrated research and management example for conserving grassland birds generally. PMID:27322196
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Rosero-García, Doris; Rúa-Uribe, Guillermo; Correa, Margarita M; Conn, Jan E; Uribe-Soto, Sandra
2018-06-01
Information about mosquito ecology in the high mountain ecosystems of the Neotropical region is sparse. In general, few genera and species have been reported in these ecosystems and there is no information available on habitats and the mosquitoes occupying them. In the present study, specimens collected from NW Colombia in HME were grouped using larval habitat data via an Operational Taxonomic Unit (OTU) determination. A total of 719 mosquitoes was analyzed belonging to 44 OTUs. The analysis considered habitat features and clustered the specimens into six groups from A-F. Five of these included species from different genera, suggesting common habitat requirements. Group E with four genera, seven subgenera, and six species occupied the highest areas (above 3,000 m), whereas three groups (B, D, F) were detected at lower altitudes (1,960-2,002 m). Bromeliads were the most common larval habitat, with 47% (335/719) of the specimens; five genera, six subgenera, and eight species were identified and classified into 66% (29/44) of the OTUs. This work showed some similarities to the habitat requirements and provides a grouping system that constitutes an important baseline for the classification of mosquito fauna from high mountain ecosystems according to altitude and larval habitat. © 2018 The Society for Vector Ecology.
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Cumulative impacts on seabed habitats: an indicator for assessments of good environmental status.
Korpinen, Samuli; Meidinger, Manuel; Laamanen, Maria
2013-09-15
The European seas are under anthropogenic pressures impacting the state of water quality, benthic habitats and species. The EU Marine Strategy Framework Directive (MSFD) requires the Member States to assess the impacts of pressures and make a programme of measures leading to good environmental status (GES) by 2020. This study presents a method for assessing the quantity and distribution of anthropogenic impacts on benthic habitats in the Baltic Sea by using spatial data of human pressures and benthic habitats. The southern sub-basins were more extensively impacted than the northern sub-basins. Over the entire sea area, deep sea habitats were more impacted than shallower infralittoral and circalittoral habitats. Sand and coarse sediments were the seabed types relatively most impacted in the Baltic Sea scale. A comparison against tentative thresholds for GES showed that in the sub-basin scale only one third of the habitat types was in GES. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Matrix quality and disturbance frequency drive evolution of species behavior at habitat boundaries.
Martin, Amanda E; Fahrig, Lenore
2015-12-01
Previous theoretical studies suggest that a species' landscape should influence the evolution of its dispersal characteristics, because landscape structure affects the costs and benefits of dispersal. However, these studies have not considered the evolution of boundary crossing, that is, the tendency of animals to cross from habitat to nonhabitat ("matrix"). It is important to understand this dispersal behavior, because of its effects on the probability of population persistence. Boundary-crossing behavior drives the rate of interaction with matrix, and thus, it influences the rate of movement among populations and the risk of dispersal mortality. We used an individual-based, spatially explicit model to simulate the evolution of boundary crossing in response to landscape structure. Our simulations predict higher evolved probabilities of boundary crossing in landscapes with more habitat, less fragmented habitat, higher-quality matrix, and more frequent disturbances (i.e., fewer generations between local population extinction events). Unexpectedly, our simulations also suggest that matrix quality and disturbance frequency have much stronger effects on the evolution of boundary crossing than either habitat amount or habitat fragmentation. Our results suggest that boundary-crossing responses are most affected by the costs of dispersal through matrix and the benefits of escaping local extinction events. Evolution of optimal behavior at habitat boundaries in response to the landscape may have implications for species in human-altered landscapes, because this behavior may become suboptimal if the landscape changes faster than the species' evolutionary response to that change. Understanding how matrix quality and habitat disturbance drive evolution of behavior at boundaries, and how this in turn influences the extinction risk of species in human-altered landscapes should help us identify species of conservation concern and target them for management.
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Object-based class modelling for multi-scale riparian forest habitat mapping
NASA Astrophysics Data System (ADS)
Strasser, Thomas; Lang, Stefan
2015-05-01
Object-based class modelling allows for mapping complex, hierarchical habitat systems. The riparian zone, including forests, represents such a complex ecosystem. Forests within riparian zones are biologically high productive and characterized by a rich biodiversity; thus considered of high community interest with an imperative to be protected and regularly monitored. Satellite earth observation (EO) provides tools for capturing the current state of forest habitats such as forest composition including intermixture of non-native tree species. Here we present a semi-automated object based image analysis (OBIA) approach for the mapping of riparian forests by applying class modelling of habitats based on the European Nature Information System (EUNIS) habitat classifications and the European Habitats Directive (HabDir) Annex 1. A very high resolution (VHR) WorldView-2 satellite image provided the required spatial and spectral details for a multi-scale image segmentation and rule-base composition to generate a six-level hierarchical representation of riparian forest habitats. Thereby habitats were hierarchically represented within an image object hierarchy as forest stands, stands of homogenous tree species and single trees represented by sunlit tree crowns. 522 EUNIS level 3 (EUNIS-3) habitat patches with a mean patch size (MPS) of 12,349.64 m2 were modelled from 938 forest stand patches (MPS = 6868.20 m2) and 43,742 tree stand patches (MPS = 140.79 m2). The delineation quality of the modelled EUNIS-3 habitats (focal level) was quantitatively assessed to an expert-based visual interpretation showing a mean deviation of 11.71%.
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A rehabilitation plan for walleye populations and habitats in Lake Superior
Hoff, Michael H.
2003-01-01
The walleye (Stizostedion vitreum vitreum) has been historically important in regional fisheries and fish communities in large bays, estuaries, and rivers of Lake Superior. Significant negative impacts on the species caused by overharvesting, habitat degradation, and pollution during the late 1800s and early 1900s have led to the preparation of a strategic rehabilitation plan. The lakewide goal is to maintain, enhance, and rehabilitate habitat for walleye and to establish self-sustaining populations in areas where walleyes historically lived. Population objectives that support the goal are to increase the abundance of juvenile and adult walleyes in selected areas. Habitat objectives that support the goal include increasing spawning and nursery habitat in four areas: enhancing fish passage, reducing sedimentation, increasing water quality, and reducing contaminants in walleyes. Progress toward achieving the habitat objectives should be measured by documenting increases in spawning and nursery habitats, resolving fish-passage issues, reducing sediments in rivers, and reducing contaminant levels in walleyes. Stocking various life stages of walleye should be considered to rehabilitate certain degraded populations. Total annual mortality of walleye populations should be less than 45% to allow populations to either increase or be maintained at target levels of abundance. Routine assessments should focus on gathering the data necessary to evaluate abundance and mortality and on taking inventories of spawning and nursery habitats. Research should be conducted to understand the specific habitat requirements for Lake Superior walleye populations and the habitat-abundance relationships for populations and for the lake as a whole.
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A Markov decision process for managing habitat for Florida scrub-jays
Johnson, Fred A.; Breininger, David R.; Duncan, Brean W.; Nichols, James D.; Runge, Michael C.; Williams, B. Ken
2011-01-01
Florida scrub-jays Aphelocoma coerulescens are listed as threatened under the Endangered Species Act due to loss and degradation of scrub habitat. This study concerned the development of an optimal strategy for the restoration and management of scrub habitat at Merritt Island National Wildlife Refuge, which contains one of the few remaining large populations of scrub-jays in Florida. There are documented differences in the reproductive and survival rates of scrubjays among discrete classes of scrub height (<120 cm or "short"; 120-170 cm or "optimal"; .170 cm or "tall"; and a combination of tall and optimal or "mixed"), and our objective was to calculate a state-dependent management strategy that would maximize the long-term growth rate of the resident scrub-jay population. We used aerial imagery with multistate Markov models to estimate annual transition probabilities among the four scrub-height classes under three possible management actions: scrub restoration (mechanical cutting followed by burning), a prescribed burn, or no intervention. A strategy prescribing the optimal management action for management units exhibiting different proportions of scrub-height classes was derived using dynamic programming. Scrub restoration was the optimal management action only in units dominated by mixed and tall scrub, and burning tended to be the optimal action for intermediate levels of short scrub. The optimal action was to do nothing when the amount of short scrub was greater than 30%, because short scrub mostly transitions to optimal height scrub (i.e., that state with the highest demographic success of scrub-jays) in the absence of intervention. Monte Carlo simulation of the optimal policy suggested that some form of management would be required every year. We note, however, that estimates of scrub-height transition probabilities were subject to several sources of uncertainty, and so we explored the management implications of alternative sets of transition probabilities
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Endangered winter-run Chinook salmon rely on diverse rearing habitats in a highly altered landscape
Phillis, Corey C.; Sturrock, Anna M.; Johnson, Rachel C.; ...
2017-11-24
Protecting habitats for imperiled species is central to conservation efforts. However, for migratory species, identifying juvenile habitats that confer success requires tracking individuals to reproduction. Here in this paper, we used otolith strontium isotope ratios ( 87Sr/ 86Sr) to reconstruct juvenile habitat use by endangered Sacramento River winter-run Chinook salmon that survived to adulthood. The isotope data revealed that 44–65% of surviving adults reared in non-natal habitats, most of which is not designated as critical habitat under the Endangered Species Act. Juveniles entered these non-natal habitats at small sizes, yet left freshwater at a similar size to those that rearedmore » in the mainstem Sacramento River, suggesting these alternate rearing habitats provide suitable growth conditions. These findings indicate Sacramento River winter-run Chinook salmon rely on rearing habitats across a broader geographic region than previously known, potentially opening up greater restoration and conservation opportunities for species recovery.« less
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Endangered winter-run Chinook salmon rely on diverse rearing habitats in a highly altered landscape
DOE Office of Scientific and Technical Information (OSTI.GOV)
Phillis, Corey C.; Sturrock, Anna M.; Johnson, Rachel C.
Protecting habitats for imperiled species is central to conservation efforts. However, for migratory species, identifying juvenile habitats that confer success requires tracking individuals to reproduction. Here in this paper, we used otolith strontium isotope ratios ( 87Sr/ 86Sr) to reconstruct juvenile habitat use by endangered Sacramento River winter-run Chinook salmon that survived to adulthood. The isotope data revealed that 44–65% of surviving adults reared in non-natal habitats, most of which is not designated as critical habitat under the Endangered Species Act. Juveniles entered these non-natal habitats at small sizes, yet left freshwater at a similar size to those that rearedmore » in the mainstem Sacramento River, suggesting these alternate rearing habitats provide suitable growth conditions. These findings indicate Sacramento River winter-run Chinook salmon rely on rearing habitats across a broader geographic region than previously known, potentially opening up greater restoration and conservation opportunities for species recovery.« less
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Aguilar, Ramiro; Ashworth, Lorena; Galetto, Leonardo; Aizen, Marcelo Adrián
2006-08-01
The loss and fragmentation of natural habitats by human activities are pervasive phenomena in terrestrial ecosystems across the Earth and the main driving forces behind current biodiversity loss. Animal-mediated pollination is a key process for the sexual reproduction of most extant flowering plants, and the one most consistently studied in the context of habitat fragmentation. By means of a meta-analysis we quantitatively reviewed the results from independent fragmentation studies throughout the last two decades, with the aim of testing whether pollination and reproduction of plant species may be differentially susceptible to habitat fragmentation depending on certain reproductive traits that typify the relationship with and the degree of dependence on their pollinators. We found an overall large and negative effect of fragmentation on pollination and on plant reproduction. The compatibility system of plants, which reflects the degree of dependence on pollinator mutualism, was the only reproductive trait that explained the differences among the species' effect sizes. Furthermore, a highly significant correlation between the effect sizes of fragmentation on pollination and reproductive success suggests that the most proximate cause of reproductive impairment in fragmented habitats may be pollination limitation. We discuss the conservation implications of these findings and give some suggestions for future research into this area.
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Habitat Suitability Index Models: Muskellunge
Cook, Mark F.; Solomon, R. Charles
1987-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the muskellunge (Esox masquinongy Mitchell). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
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Austin, Jane E.; O'Neil, Shawn T.; Warren, Jeffrey M.
2017-01-01
Habitat selection studies of postbreeding waterfowl have rarely focused on within-wetland attributes such as water depth, escape cover, and food availability. Flightless waterfowl must balance habitat selection between avoiding predation risks and feeding. Reproductively successful female ducks face the greatest challenges because they begin the definitive prebasic molt at or near the end of brood rearing, when their body condition is at a low point. We assessed the relative importance of habitat attributes and group effects in habitat selection by postbreeding female lesser scaup Aythya affinis on a 2332-ha montane wetland complex during the peak flightless period (August) over seven years. Hypothesis-based habitat attributes included percent open water, open water:emergent edge density, water depth, percent flooded bare substrate, fetch (distance wind can travel unobstructed), group size, and several interactions representing functional responses to interannual variation in water levels. Surveys of uniquely marked females were conducted within randomly ordered survey blocks. We fitted two-part generalized linear mixed-effects models to counts of marked females within survey blocks, which allowed us to relate habitat attributes to relative probability of occurrence and, given the presence of a marked female, abundance of marked individuals. Postbreeding female scaup selected areas with water depths > 40 cm, large open areas, and intermediate edge densities but showed no relation to flooded bare substrate, suggesting their habitat preferences were more influenced by avoiding predation risks and disturbances than in meeting foraging needs. Grouping behavior by postbreeding scaup suggests habitat selection is influenced in part by behavioral components and/or social information, conferring energetic and survival benefits (predation and disturbance risks) but potentially also contributing to competition for food resources. This study demonstrates the importance of
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Diversity and Community Composition of Vertebrates in Desert River Habitats
Free, C. L.; Baxter, G. S.; Dickman, C. R.; Lisle, A.; Leung, L. K.-P.
2015-01-01
Animal species are seldom distributed evenly at either local or larger spatial scales, and instead tend to aggregate in sites that meet their resource requirements and maximise fitness. This tendency is likely to be especially marked in arid regions where species could be expected to concentrate at resource-rich oases. In this study, we first test the hypothesis that productive riparian sites in arid Australia support higher vertebrate diversity than other desert habitats, and then elucidate the habitats selected by different species. We addressed the first aim by examining the diversity and composition of vertebrate assemblages inhabiting the Field River and adjacent sand dunes in the Simpson Desert, western Queensland, over a period of two and a half years. The second aim was addressed by examining species composition in riparian and sand dune habitats in dry and wet years. Vertebrate species richness was estimated to be highest (54 species) in the riverine habitats and lowest on the surrounding dune habitats (45 species). The riverine habitats had different species pools compared to the dune habitats. Several species, including the agamid Gowidon longirostris and tree frog Litoria rubella, inhabited the riverine habitats exclusively, while others such as the skinks Ctenotus ariadnae and C. dux were captured only in the dune habitats. The results suggest that, on a local scale, diversity is higher along riparian corridors and that riparian woodland is important for tree-dependent species. Further, the distribution of some species, such as Mus musculus, may be governed by environmental variables (e.g. soil moisture) associated with riparian corridors that are not available in the surrounding desert environment. We conclude that inland river systems may be often of high conservation value, and that management should be initiated where possible to alleviate threats to their continued functioning. PMID:26637127
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Diet preferences of goats in a subtropical dry forest and implications for habitat management
Genie M. Fleming; Joseph Wunderle Jr.; David N. Ewert
2016-01-01
As part of an experimental study of using controlled goat grazing to manage winter habitat of the Kirtlandâs warbler (Setophaga kirtlandii), an endangered Nearctic neotropical migratory bird, we evaluated diet preferences of domesticated goats within early successional subtropical dry forest in The Bahamas. We expected goats would show a low preference for two plants (...
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Habitat Complexity Metrics to Guide Restoration of Large Rivers
NASA Astrophysics Data System (ADS)
Jacobson, R. B.; McElroy, B. J.; Elliott, C.; DeLonay, A.
2011-12-01
complexity metrics is complicated by the fact that characteristics of channel morphology may increase complexity scores without necessarily increasing biophysical capacity for target species. For example, a cross section that samples depths and velocities across the thalweg (navigation channel) and into lentic habitat may score high on most measures of hydraulic or geomorphic complexity, but does not necessarily provide habitats beneficial to native species. Complexity measures need to be bounded by best estimates of native species requirements. In the absence of specific information, creation of habitat complexity for the sake of complexity may lead to unintended consequences, for example, lentic habitats that increase a complexity score but support invasive species. An additional practical constraint on complexity measures is the need to develop metrics that are can be deployed cost-effectively in an operational monitoring program. Design of a monitoring program requires informed choices of measurement variables, definition of reference sites, and design of sampling effort to capture spatial and temporal variability.
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Habitat suitability models are useful to forecast how environmental change may affect the abundance or distribution of species of interest. In the case of harvested bivalves, those models may be used to estimate the vulnerability of this valued ecosystem good to stressors. Using ...
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Habitat suitability models are useful to forecast how environmental change may affect the abundance or distribution of species of interest. In the case of harvested bivalves, those models may be used to estimate the vulnerability of this valued ecosystem good to stressors. Using ...
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Habitat risk assessment for regional ocean planning in the U.S. Northeast and Mid-Atlantic.
Wyatt, Katherine H; Griffin, Robert; Guerry, Anne D; Ruckelshaus, Mary; Fogarty, Michael; Arkema, Katie K
2017-01-01
Coastal habitats provide important benefits to people, including habitat for species targeted by fisheries and opportunities for tourism and recreation. Yet, such human activities also can imperil these habitats and undermine the ecosystem services they provide to people. Cumulative risk assessment provides an analytical framework for synthesizing the influence of multiple stressors across habitats and decision-support for balancing human uses and ecosystem health. To explore cumulative risk to habitats in the U.S. Northeast and Mid-Atlantic Ocean Planning regions, we apply the open-source InVEST Habitat Risk Assessment model to 13 habitats and 31 stressors in an exposure-consequence framework. In doing so, we advance the science priorities of EBM and both regional planning bodies by synthesizing the wealth of available data to improve our understanding of human uses and how they affect marine resources. We find that risk to ecosystems is greatest first, along the coast, where a large number of stressors occur in close proximity and secondly, along the continental shelf, where fewer, higher consequence activities occur. Habitats at greatest risk include soft and hard-bottom nearshore areas, tidal flats, soft-bottom shelf habitat, and rocky intertidal zones-with the degree of risk varying spatially. Across all habitats, our results indicate that rising sea surface temperatures, commercial fishing, and shipping consistently and disproportionally contribute to risk. Further, our findings suggest that management in the nearshore will require simultaneously addressing the temporal and spatial overlap as well as intensity of multiple human activities and that management in the offshore requires more targeted efforts to reduce exposure from specific threats. We offer a transparent, generalizable approach to evaluating cumulative risk to multiple habitats and illustrate the spatially heterogeneous nature of impacts along the eastern Atlantic coast and the importance of
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Habitat risk assessment for regional ocean planning in the U.S. Northeast and Mid-Atlantic
Guerry, Anne D.; Ruckelshaus, Mary; Fogarty, Michael; Arkema, Katie K.
2017-01-01
Coastal habitats provide important benefits to people, including habitat for species targeted by fisheries and opportunities for tourism and recreation. Yet, such human activities also can imperil these habitats and undermine the ecosystem services they provide to people. Cumulative risk assessment provides an analytical framework for synthesizing the influence of multiple stressors across habitats and decision-support for balancing human uses and ecosystem health. To explore cumulative risk to habitats in the U.S. Northeast and Mid-Atlantic Ocean Planning regions, we apply the open-source InVEST Habitat Risk Assessment model to 13 habitats and 31 stressors in an exposure-consequence framework. In doing so, we advance the science priorities of EBM and both regional planning bodies by synthesizing the wealth of available data to improve our understanding of human uses and how they affect marine resources. We find that risk to ecosystems is greatest first, along the coast, where a large number of stressors occur in close proximity and secondly, along the continental shelf, where fewer, higher consequence activities occur. Habitats at greatest risk include soft and hard-bottom nearshore areas, tidal flats, soft-bottom shelf habitat, and rocky intertidal zones—with the degree of risk varying spatially. Across all habitats, our results indicate that rising sea surface temperatures, commercial fishing, and shipping consistently and disproportionally contribute to risk. Further, our findings suggest that management in the nearshore will require simultaneously addressing the temporal and spatial overlap as well as intensity of multiple human activities and that management in the offshore requires more targeted efforts to reduce exposure from specific threats. We offer a transparent, generalizable approach to evaluating cumulative risk to multiple habitats and illustrate the spatially heterogeneous nature of impacts along the eastern Atlantic coast and the importance of
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2009-10-13
Unfrozen brine in cryopegs and fracture networks provides habitats for the survival and growth of organisms both within and under frozen rocky materials on Earth and, by analogy, could provide habitats on Mars.
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Volumetric integration of functions for a long term initial Mars habitat
NASA Astrophysics Data System (ADS)
Gutierrez, David John
Sucessfully planning a manned mission to Mars involves an extraordinary balance of resources, risk, technology development and innovation. The interdependency of these factors will ultimately drive out more feasible scenarios for supporting humans during three year, or longer, missions to the Mars surface and home to Earth. Based on a mission profile developed in the Exploration Programs Office at the Johnson Space Center, the Flight Crew Support division began developing conceptual Mars surface habitats to drive out the early human support issues and habitat development concerns. Following the completion of an analysis of a horizontally oriented and outfitted Initial Lunar Haitat (ILH), the decision was made to focus on a vertically oriented habitat as a comparative study. Drawing from the results of both KC-135 partial gravity locomotion testing and water immersion vertical translation studies, the Initial Mars Habitat (IMH), is an analysis of the habitat systems, volumes, and capabilities required to support the first crew of six on the surface of Mars for 500 to 600 days.
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Hart, Kristen M.; Zawada, David G.; Sartain-Iverson, Autumn R.; Fujisaki, Ikuko
2016-01-01
We used satellite telemetry to identify in-water habitat used by individuals in the smallest North-west Atlantic subpopulation of adult nesting loggerhead turtles Caretta caretta during the breeding season. During 2010, 2011 and 2012 breeding periods, a total of 20 adult females used habitats proximal to nesting beaches with various levels of protection within Dry Tortugas National Park. We then used a rapid, high-resolution, digital imaging system to map habitat adjacent to nesting beaches, revealing the diversity and distribution of available benthic cover. Turtle behaviour showing measurable site-fidelity to these diverse habitats has implications for managing protected areas and human activities within them. Protecting diverse benthic areas adjacent to loggerhead turtle nesting beaches here and elsewhere could provide benefits for overall biodiversity conservation.
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Landscape habitat suitability index software
William D. Dijak; Chadwick D. Rittenhouse; Michael A. Larson; Frank R. III Thompson; Joshua J. Millspaugh
2007-01-01
Habitat suitability index (HSI) models are traditionally used to evaluate habitat quality for wildlife at a local scale. Rarely have such models incorporated spatial relationships of habitat components. We introduce Landscape HSImodels, a new Microsoft Windowst (Microsoft, Redmond, WA)-based program that incorporates local habitat as well as landscape-scale attributes...
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Using dynamic Brownian bridge movement modelling to measure temporal patterns of habitat selection.
Byrne, Michael E; Clint McCoy, J; Hinton, Joseph W; Chamberlain, Michael J; Collier, Bret A
2014-09-01
Accurately describing animal space use is vital to understanding how wildlife use habitat. Improvements in GPS technology continue to facilitate collection of telemetry data at high spatial and temporal resolutions. Application of the recently introduced dynamic Brownian bridge movement model (dBBMM) to such data is promising as the method explicitly incorporates the behavioural heterogeneity of a movement path into the estimated utilization distribution (UD). Utilization distributions defining space use are normally estimated for time-scales ranging from weeks to months, obscuring much of the fine-scale information available from high-volume GPS data sets. By accounting for movement heterogeneity, the dBBMM provides a rigorous, behaviourally based estimate of space use between each set of relocations. Focusing on UDs generated between individual sets of locations allows us to quantify fine-scale circadian variation in habitat use. We used the dBBMM to estimate UDs bounding individual time steps for three terrestrial species with different life histories to illustrate how the method can be used to identify fine-scale variations in habitat use. We also demonstrate how dBBMMs can be used to characterize circadian patterns of habitat selection and link fine-scale patterns of habitat use to behaviour. We observed circadian patterns of habitat use that varied seasonally for a white-tailed deer (Odocoileus virginianus) and coyote (Canis latrans). We found seasonal patterns in selection by the white-tailed deer and were able to link use of conifer forests and agricultural fields to behavioural state of the coyote. Additionally, we were able to quantify the date in which a Rio Grande wild turkey (Meleagris gallopavo intermedia) initiated laying as well as when during the day, she was most likely to visit the nest site to deposit eggs. The ability to quantify circadian patterns of habitat use may have important implications for research and management of wildlife
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Aedes aegypti and Aedes albopictus Habitat Preferences in South Texas, USA
Champion, Samantha R; Vitek, Christopher J
2014-01-01
The South Texas region has a historical record of occasional dengue outbreaks. The recent introduction of chikungunya virus to the Caribbean suggests that this disease may be a concern as well. Six different cities and three field habitat types (residential, tire shops, and cemeteries) were examined for evidence of habitat and longitudinal preference of two vector species, Aedes aegypti and Aedes albopictus. A. aegypti was more prevalent in tire shop sites, while A. albopictus was more prevalent in cemetery sites. In residential sites, the relative abundance of the two species varied with longitude, with A. albopictus being more abundant near the coast, and A. aegypti being more abundant inland. There was also a temporal variation, with A. aegypti declining in frequency over time in residential sites. These results have implications for control strategies and disease risk and suggest a greater need for increased surveillance and research in the region. PMID:25520559
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Predicting habitat distribution to conserve seagrass threatened by sea level rise
NASA Astrophysics Data System (ADS)
Saunders, M. I.; Baldock, T.; Brown, C. J.; Callaghan, D. P.; Golshani, A.; Hamylton, S.; Hoegh-guldberg, O.; Leon, J. X.; Lovelock, C. E.; Lyons, M. B.; O'Brien, K.; Mumby, P.; Phinn, S. R.; Roelfsema, C. M.
2013-12-01
Sea level rise (SLR) over the 21st century will cause significant redistribution of valuable coastal habitats. Seagrasses form extensive and highly productive meadows in shallow coastal seas support high biodiversity, including economically valuable and threatened species. Predictive habitat models can inform local management actions that will be required to conserve seagrass faced with multiple stressors. We developed novel modelling approaches, based on extensive field data sets, to examine the effects of sea level rise and other stressors on two representative seagrass habitats in Australia. First, we modelled interactive effects of SLR, water clarity and adjacent land use on estuarine seagrass meadows in Moreton Bay, Southeast Queensland. The extent of suitable seagrass habitat was predicted to decline by 17% by 2100 due to SLR alone, but losses were predicted to be significantly reduced through improvements in water quality (Fig 1a) and by allowing space for seagrass migration with inundation. The rate of sedimentation in seagrass strongly affected the area of suitable habitat for seagrass in sea level rise scenarios (Fig 1b). Further research to understand spatial, temporal and environmental variability of sediment accretion in seagrass is required. Second, we modelled changes in wave energy distribution due to predicted SLR in a linked coral reef and seagrass ecosystem at Lizard Island, Great Barrier Reef. Scenarios where the water depth over the coral reef deepened due to SLR and minimal reef accretion, resulted in larger waves propagating shoreward, changing the existing hydrodynamic conditions sufficiently to reduce area of suitable habitat for seagrass. In a scenario where accretion of the coral reef was severely compromised (e.g. warming, acidification, overfishing), the probability of the presence of seagrass declined significantly. Management to maintain coral health will therefore also benefit seagrasses subject to SLR in reef environments. Further
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Habitat Suitability Index Models: Yellow perch
Krieger, Douglas A.; Terrell, James W.; Nelson, Patrick C.
1983-01-01
A review and synthesis of existing information were used to develop riverine and lacustrine habitat models for yellow perch (Perca flavescens). The models are scaled to produce an index of habitat suitability between 0 (unsuitable habitat) to 1 (optimally suitable habitat) for riverine, lacustrine, and palustrine habitat in the 48 contiguous United States. Habitat Suitability Indexes (HSI's) are designed for use with the Habitat Evaluation Procedures developed by the U.S. Fish and Wildlife Service. Also included are discussions of Suitability Index (SI) curves as used in the Instream Flow Incremental Methodology (IFIM) and SI curves available for an IFIM analysis of yellow perch habitat.
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Effects of tide cycles on habitat selection and habitat partitioning by migrating shorebirds
Burger, J.; Howe, M.A.; Hahn, D.C.; Chase, J.
1977-01-01
We studied assemblages of feeding shorebirds in three intertidal habitats on the coast of New Jersey during August to document how species segregate spatially both among and within habitats and to determine the effects of tidal cycles on these patterns. The habitats were a sandy beach facing the ocean proper (outer beach), a sandy beach on the mainland side of a barrier island (inner beach), and a small mudflat adjacent to a Spartina alterniflora salt marsh. We were able to identify several microhabitats on the outer beach and mudflat. Most species fed in more than one habitat, but only two, Charadrius semipalmatus and Calidris canutus, used all three habitats regularly. Within habitats, most species exhibited strong preferences for the wettest areas, but we found differences among species in degrees of preference. The least amount of partitioning occurred on the inner beach, where birds crowded into a small zone near the water's edge and had frequent agonistic encounters suggesting intense competition. Shorebird feeding activity was partly a function of tide time: each habitat had a characteristic temporal pattern of use by shorebirds related to tide time rather than diel time; within habitats, we found species-characteristic feeding activity rhythms that were also a function of tide time. Feeding by most species peaked during the first 2 hours after low tide on the outer beach and mudflat. The results are discussed in terms of feeding strategies and interspecific competition.
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Marten habitat preferences in the northern Sierra Nevada
Wayne D. Spencer; Reginald H. Barrett; William J. Zielinski
1983-01-01
Escalating harvest of remnant oldgrowth forests in the Pacific Northwest has precipitated concern for marten (Martes americana) as an old-growth dependent species (Meslow et al. 1981). Although recent studies have increased our understanding of marten habitat requirements (Koehler and Hornocker 1977, Soutiere 1979, Steventon and Major 1982), little...
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ERIC Educational Resources Information Center
Fish and Wildlife Service (Dept. of Interior), Washington, DC.
The materials in this educational packet are designed for use with students in grades 4 through 7. They consist of an overview, teaching guides and student data sheets for three activities, and a poster. The overview discusses the city as an ecosystem, changing urban habitats, urban wildlife habitats, values of wildlife, habitat management, and…
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Principles of wildlife habitat management
Ernie P. Wiggers
1989-01-01
Simply stated, habitat is where an animal lives and must include all the resources an animal needs to survive and reproduce. An animal's habitat has to provide five essential factors: food, cover, water, space, and interspersion. Habitat management is identifying which factors are scarce enough to limit populations, and then improving the habitat to remove the...
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Expandable Lunar Habitat (X-Hab)
2010-09-23
Expandable Lunar Habitat (X-Hab).ILC Dover, under contract by NASA Langley Research Center, and in cooperation with NASA Johnson Space Center has designed and manufactured an expandable lunar habitat. This cylindrical habitat, or Expandable Lunar Habitat (X-Hab) is a hybrid system with two hard end caps and a deployable softgoods section in the center.
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K.M. Bergen; S.J. Goetz; R.O. Dubayah; G.M. Henebry; C.T. Hunsaker; M.L. Imhoff; R.F. Nelson; G.G. Parker; V.C. Radeloff
2009-01-01
Biodiversity and habitat face increasing pressures due to human and natural influences that alter vegetation structure. Because of the inherent difficulty of measuring forested vegetation three-dimensional (3-D) structure on the ground, this important component of biodiversity and habitat has been, until recently, largely restricted to local measurements, or at larger...
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Thom, Ronald M.; Borde, Amy B.
2015-09-01
Restoring estuarine habitats generally means repairing damages caused by humans and natural forces. Because of the extensive human occupation, development, and use of coastal areas for centuries, the extensive estuarine habitats have been either destroyed or significantly impaired.
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City life makes females fussy: sex differences in habitat use of temperate bats in urban areas
Lintott, Paul R.; Bunnefeld, Nils; Fuentes-Montemayor, Elisa; Minderman, Jeroen; Mayhew, Rebekah J.; Olley, Lena; Park, Kirsty J.
2014-01-01
Urbanization is a major driver of the global loss of biodiversity; to mitigate its adverse effects, it is essential to understand what drives species' patterns of habitat use within the urban matrix. While many animal species are known to exhibit sex differences in habitat use, adaptability to the urban landscape is commonly examined at the species level, without consideration of intraspecific differences. The high energetic demands of pregnancy and lactation in female mammals can lead to sexual differences in habitat use, but little is known of how this might affect their response to urbanization. We predicted that female Pipistrellus pygmaeus would show greater selectivity of forging locations within urban woodland in comparison to males at both a local and landscape scale. In line with these predictions, we found there was a lower probability of finding females within woodlands which were poorly connected, highly cluttered, with a higher edge : interior ratio and fewer mature trees. By contrast, habitat quality and the composition of the surrounding landscape were less of a limiting factor in determining male distributions. These results indicate strong sexual differences in the habitat use of fragmented urban woodland, and this has important implications for our understanding of the adaptability of bats and mammals more generally to urbanization. PMID:26064557
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Habitat model for the Florida Scrub Jay on John F. Kennedy Space Center
NASA Technical Reports Server (NTRS)
Breininger, David R.
1992-01-01
The Florida Scrub Jay is endemic to Florida. The John F. Kennedy Space Center (KSC) provides habitat for one of the three largest populations of the Florida Scrub Jay. This threatened bird occupies scrub, slash pine flatwoods, disturbed scrub, and coastal strand on KSC. Densities of Florida Scrub Jays were shown to vary with habitat characteristics but not necessarily with vegetation type. Relationships between Florida Scrub Jay densities and habitat characteristics were used to develop a habitat model to provide a tool to compare alternative sites for new facilities and to quantify environmental impacts. This model is being tested using long term demographic studies of colorbanded Florida Scrub Jays. Optimal habitat predicted by the model has greater than or equal to 50 percent of the shrub canopy comprised of scrub oaks, 20-50 percent open space or scrub oak vegetation within 100 m of a ruderal edge, less than or equal to 15 percent pine canopy cover, a shrub height of 120-170 cm, and is greater than or equal to 100 m from a forest. This document reviews life history, social behavior, food, foraging habitat, cover requirements, characteristics of habitat on KSC, and habitat preferences of the Florida Scrub Jay. Construction of the model and its limitations are discussed.
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Heinrichs, Julie; Aldridge, Cameron L.; O'Donnell, Michael; Schumaker, Nathan
2017-01-01
Prioritizing habitats for conservation is a challenging task, particularly for species with fluctuating populations and seasonally dynamic habitat needs. Although the use of resource selection models to identify and prioritize habitat for conservation is increasingly common, their ability to characterize important long-term habitats for dynamic populations are variable. To examine how habitats might be prioritized differently if resource selection was directly and dynamically linked with population fluctuations and movement limitations among seasonal habitats, we constructed a spatially explicit individual-based model for a dramatically fluctuating population requiring temporally varying resources. Using greater sage-grouse (Centrocercus urophasianus) in Wyoming as a case study, we used resource selection function maps to guide seasonal movement and habitat selection, but emergent population dynamics and simulated movement limitations modified long-term habitat occupancy. We compared priority habitats in RSF maps to long-term simulated habitat use. We examined the circumstances under which the explicit consideration of movement limitations, in combination with population fluctuations and trends, are likely to alter predictions of important habitats. In doing so, we assessed the future occupancy of protected areas under alternative population and habitat conditions. Habitat prioritizations based on resource selection models alone predicted high use in isolated parcels of habitat and in areas with low connectivity among seasonal habitats. In contrast, results based on more biologically-informed simulations emphasized central and connected areas near high-density populations, sometimes predicted to be low selection value. Dynamic models of habitat use can provide additional biological realism that can extend, and in some cases, contradict habitat use predictions generated from short-term or static resource selection analyses. The explicit inclusion of population
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Home range dynamics, habitat selection, and survival of Greater Roadrunners
Kelley, S.W.; Ransom, D.; Butcher, J.A.; Schulz, G.G.; Surber, B.W.; Pinchak, W.E.; Santamaria, C.A.; Hurtado, L.A.
2011-01-01
Greater Roadrunners (Geococcyx californianus) are common, poorly studied birds of arid and semi-arid ecosystems in the southwestern United States. Conservation of this avian predator requires a detailed understanding of their movements and spatial requirements that is currently lacking. From 2006 to 2009, we quantified home-range and core area sizes and overlap, habitat selection, and survival of roadrunners (N= 14 males and 20 females) in north-central Texas using radio-telemetry and fixed kernel estimators. Median home-range and core-area sizes were 90.4 ha and 19.2 ha for males and 80.1 ha and 16.7 ha for females, respectively. The size of home range and core areas did not differ significantly by either sex or season. Our home range estimates were twice as large (x??= 108.9 ha) as earlier published estimates based on visual observations (x??= 28-50 ha). Mean percent overlap was 38.4% for home ranges and 13.7% for core areas. Male roadrunners preferred mesquite woodland and mesquite savanna cover types, and avoided the grass-forb cover type. Female roadrunners preferred mesquite savanna and riparian woodland cover types, and avoided grass-forb habitat. Kaplan-Meier annual survival probabilities for females (0.452 ?? 0.118[SE]) were twice that estimated for males (0.210 ?? 0.108), but this difference was not significant. Mortality rates of male roadrunners were higher than those of females during the spring when males call from elevated perches, court females, and chase competing males. Current land use practices that target woody-shrub removal to enhance livestock forage production could be detrimental to roadrunner populations by reducing availability of mesquite woodland and mesquite savanna habitat required for nesting and roosting and increasing the amount of grass-forb habitat that roadrunners avoid. ??2011 The Authors. Journal of Field Ornithology ??2011 Association of Field Ornithologists.
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Leduc, Daniel; Rowden, Ashley A.; Clark, Malcolm R.; Probert, P. Keith; Berkenbusch, Katrin; Neira, Carlos
2016-01-01
Studies of deep-sea benthic communities have largely focused on particular (macro) habitats in isolation, with few studies considering multiple habitats simultaneously in a comparable manner. Compared to mega-epifauna and macrofauna, much less is known about habitat-related variation in meiofaunal community attributes (abundance, diversity and community structure). Here, we investigated meiofaunal community attributes in slope, canyon, seamount, and seep habitats in two regions on the continental slope of New Zealand (Hikurangi Margin and Bay of Plenty) at four water depths (700, 1,000, 1,200 and 1,500 m). We found that patterns were not the same for each community attribute. Significant differences in abundance were consistent across regions, habitats, water and sediment depths, while diversity and community structure only differed between sediment depths. Abundance was higher in canyon and seep habitats compared with other habitats, while between sediment layer, abundance and diversity were higher at the sediment surface. Our findings suggest that meiofaunal community attributes are affected by environmental factors that operate on micro- (cm) to meso- (0.1–10 km), and regional scales (> 100 km). We also found a weak, but significant, correlation between trawling intensity and surface sediment diversity. Overall, our results indicate that variability in meiofaunal communities was greater at small scale than at habitat or regional scale. These findings provide new insights into the factors controlling meiofauna in these deep-sea habitats and their potential vulnerability to anthropogenic activities. PMID:27441114
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Joseph L. Ganey; William M. Block; Jamie S. Sanderlin; Jose M. Iniguez
2015-01-01
Conservation of avian species requires understanding their nesting habitat requirements. We compared 3 aspects of habitat at nest sites (topographic characteristics of nest sites, nest placement within nest sites, and canopy stratification within nest sites) of 2 related species of ground-nesting warblers (Red-faced Warblers, Cardellina rubrifrons, n = 17...
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William J. Zielinski; Jeffrey R. Dunk; Andrew N. Gray
2012-01-01
Managing forests for multiple objectives requires balancing timber and vegetation management objectives with needs of sensitive species. Especially challenging is how to retain the habitat elements for species that are typically associated with late-seral forests. We develop a regionally specific, multivariate model describing habitat selection that can be used â when...
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Jezberová, Jitka; Jezbera, Jan; Brandt, Ulrike; Lindström, Eva S.; Langenheder, Silke; Hahn, Martin W.
2010-01-01
Summary We present a survey on the distribution and habitat range of P. necessarius subspecies asymbioticus (PnecC), an important taxon in the water column of freshwater systems. We systematically sampled stagnant freshwater habitats in a heterogeneous 2000 km2 area, together with ecologically different habitats outside this area. In total, 137 lakes, ponds and puddles were investigated, which represent an enormous diversity of habitats differing, i.e., in depth (<10 cm – 171 m) and pH (3.9 – 8.5). PnecC was detected by cultivation-independent methods in all investigated habitats, and its presence was confirmed by cultivation of strains from selected habitats including the most extreme ones. The determined relative abundance of the subspecies ranged from slightly above 0% to 67% (average 14.5% ± 14.3%), and the highest observed absolute abundance was 5.3×106 cells mL−1. Statistical analyses revealed that the abundance of PnecC is partially controlled by factors linked to concentrations of humic substances, which might support the hypothesis that these bacteria utilize photodegradation products of humic substances. . Statistical analyses revealed that the abundance of PnecC is partially controlled by low conductivity and pH and factors linked to concentrations of humic substances. Based on the revealed statistical relationships, an average relative abundance of this subspecies of 20% in global freshwater habitats was extrapolated. Our study provides important implications for the current debate on ubiquity and biogeography in microorganisms. PMID:20041938
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-21
... Estuary Habitat Restoration Council's Intent to Revise its Estuary Habitat Restoration Strategy; Request... interagency Estuary Habitat Restoration Council, is providing notice of the Council's intent to revise the ''Estuary Habitat Restoration Strategy'' and requesting public comments to guide its revision. DATES...
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Vacant habitats in the Universe.
Cockell, Charles S
2011-02-01
The search for life on other planets usually makes the assumption that where there is a habitat, it will contain life. On the present-day Earth, uninhabited habitats (or vacant habitats) are rare, but might occur, for example, in subsurface oils or impact craters that have been thermally sterilized in the past. Beyond Earth, vacant habitats might similarly exist on inhabited planets or on uninhabited planets, for example on a habitable planet where life never originated. The hypothesis that vacant habitats are abundant in the Universe is testable by studying other planets. In this review, I discuss how the study of vacant habitats might ultimately inform an understanding of how life has influenced geochemical conditions on Earth. Copyright © 2010 Elsevier Ltd. All rights reserved.
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Habitat planning, maintenance and management working group
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
The Gulf of Mexico (GOM), called {open_quotes}America`s Sea,{close_quotes} is actually a small ocean basin covering over 1.5 million square kilometers. Because of the multiple uses, diversity, and size of the Gulf`s resources, management is shared by a number of governmental agencies including the Minerals Management Service, the Gulf of Mexico Fishery Management Council, the Gulf States Marine Fisheries Commission, National Marine Fisheries Service, the US Coast Guard, the US Army Corps of Engineers, and the five Gulf states fisheries agencies. All of these entities share a common goal of achieving optimum sustainable yield to maximize geological, biological, social, and economicmore » benefits from these resources. These entities also share a common theme that the successful management of the northern GOM requires maintenance and enhancement of both the quantity and quality of habitats. A closer look at the GOM shows the sediment to be clearly dominated by vast sand and mud plains. These soft bottom habitats are preferred by many groundfish and shrimp species and, thus, have given rise to large commercial fisheries on these stocks. Hard bottom and reef habitats, on the other hand, are limited to approximately 1.6% of the total area of the Gulf, so that, while there are high demands by commercial and recreational fishermen for reef associated species, the availability of habitat for these stocks is limited. The thousands of oil and gas structures placed in the Gulf have added significant amounts of new hard substrate. The rigs-to-reefs concept was a common sense idea with support from environmental user groups and the petroleum industry for preserving a limited but valuable habitat type. As long as maximizing long-term benefits from the Gulf s resources for the greatest number of users remains the goal, then programs such as Rigs-to-Reefs will remain an important tool for fisheries and habitat managers in the Gulf.« less
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NASA Astrophysics Data System (ADS)
Székely, B.; Kania, A.; Pfeifer, N.; Heilmeier, H.; Tamás, J.; Szöllősi, N.; Mücke, W.
2012-04-01
The goal of the ChangeHabitats2 project is the development of cost- and time-efficient habitat assessment strategies by employing effective field work techniques supported by modern airborne remote sensing methods, i.e. hyperspectral imagery and laser scanning (LiDAR). An essential task of the project is the design of a novel field work technique that on the one hand fulfills the reporting requirements of the Flora-Fauna-Habitat (FFH-) directive and on the other hand serves as a reference for the aerial data analysis. Correlations between parameters derived from remotely sensed data and terrestrial field measurements shall be exploited in order to create half- or fully-automated methods for the extraction of relevant Natura2000 habitat parameters. As a result of these efforts a comprehensive conceptual model has been developed for extraction and integration of Natura 2000 relevant geospatial data. This scheme is an attempt to integrate various activities within ChangeHabitats2 project defining pathways of development, as well as encompassing existing data processing chains, theoretical approaches and field work. The conceptual model includes definition of processing levels (similar to those existing in remote sensing), whereas these levels cover the range from the raw data to the extracted habitat feature. For instance, the amount of dead wood (standing or lying on the surface) is an important evaluation criterion for the habitat. The tree trunks lying on the ground surface typically can be extracted from the LiDAR point cloud, and the amount of wood can be estimated accordingly. The final result will be considered as a habitat feature derived from laser scanning data. Furthermore, we are also interested not only in the determination of the specific habitat feature, but also in the detection of its variations (especially in deterioration). In this approach the variation of this important habitat feature is considered to be a differential habitat feature, that can
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NASA Astrophysics Data System (ADS)
Altmoos, Michael; Henle, Klaus
2010-11-01
Habitat models for animal species are important tools in conservation planning. We assessed the need to consider several scales in a case study for three amphibian and two grasshopper species in the post-mining landscapes near Leipzig (Germany). The two species groups were selected because habitat analyses for grasshoppers are usually conducted on one scale only whereas amphibians are thought to depend on more than one spatial scale. First, we analysed how the preference to single habitat variables changed across nested scales. Most environmental variables were only significant for a habitat model on one or two scales, with the smallest scale being particularly important. On larger scales, other variables became significant, which cannot be recognized on lower scales. Similar preferences across scales occurred in only 13 out of 79 cases and in 3 out of 79 cases the preference and avoidance for the same variable were even reversed among scales. Second, we developed habitat models by using a logistic regression on every scale and for all combinations of scales and analysed how the quality of habitat models changed with the scales considered. To achieve a sufficient accuracy of the habitat models with a minimum number of variables, at least two scales were required for all species except for Bufo viridis, for which a single scale, the microscale, was sufficient. Only for the European tree frog ( Hyla arborea), at least three scales were required. The results indicate that the quality of habitat models increases with the number of surveyed variables and with the number of scales, but costs increase too. Searching for simplifications in multi-scaled habitat models, we suggest that 2 or 3 scales should be a suitable trade-off, when attempting to define a suitable microscale.
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Holyoak, Marcel; Heath, Sacha K
2016-01-01
A growing number of studies have looked at how climate change alters the effects of habitat fragmentation and degradation on both single and multiple species; some raise concern that biodiversity loss and its effects will be exacerbated. The published literature on spatial dynamics (such as dispersal and metapopulation dynamics), habitat fragmentation and climate change requires synthesis and a conceptual framework to simplify thinking. We propose a framework that integrates how climate change affects spatial population dynamics and the effects of habitat fragmentation in terms of: (i) habitat quality, quantity and distribution; (ii) habitat connectivity; and (iii) the dynamics of habitat itself. We use the framework to categorize existing autecological studies and investigate how each is affected by anthropogenic climate change. It is clear that a changing climate produces changes in the geographic distribution of climatic conditions, and the amount and quality of habitat. The most thorough published studies show how such changes impact metapopulation persistence, source-sink dynamics, changes in species' geographic range and community composition. Climate-related changes in movement behavior and quantity, quality and distribution of habitat have also produced empirical changes in habitat connectivity for some species. An underexplored area is how habitat dynamics that are driven by climatic processes will affect species that live in dynamic habitats. We end our discussion by suggesting ways to improve current attempts to integrate climate change, spatial population dynamics and habitat fragmentation effects, and suggest distinct areas of study that might provide opportunities for more fully integrative work. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.
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Walston, Leroy J; Mishra, Shruti K; Hartmann, Heidi M; Hlohowskyj, Ihor; McCall, James; Macknick, Jordan
2018-06-13
Of the many roles insects serve for ecosystem function, pollination is possibly the most important service directly linked to human well-being. However, land use changes have contributed to the decline of pollinators and their habitats. In agricultural landscapes that also support renewable energy developments such as utility-scale solar energy [USSE] facilities, opportunities may exist to conserve insect pollinators and locally restore their ecosystem services through the implementation of vegetation management approaches that aim to provide and maintain pollinator habitat at USSE facilities. As a first step toward understanding the potential agricultural benefits of solar-pollinator habitat, we identified areas of overlap between USSE facilities and surrounding pollinator-dependent crop types in the United States (U.S.). Using spatial data on solar energy developments and crop types across the U.S., and assuming a pollinator foraging distance of 1.5 km, we identified over 3,500 km 2 of agricultural land near existing and planned USSE facilities that may benefit from increased pollination services through the creation of pollinator habitat at the USSE facilities. The following five pollinator-dependent crop types accounted for over 90% of the agriculture near USSE facilities, and these could benefit most from the creation of pollinator habitat at existing and planned USSE facilities: soybeans, alfalfa, cotton, almonds, and citrus. We discuss how our results may be used to understand potential agro-economic implications of solar-pollinator habitat. Our results show that ecosystem service restoration through the creation of pollinator habitat could improve the sustainability of large-scale renewable energy developments in agricultural landscapes.
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Aldridge, Cameron L.; Boyce, Mark S.
2007-01-01
Detailed empirical models predicting both species occurrence and fitness across a landscape are necessary to understand processes related to population persistence. Failure to consider both occurrence and fitness may result in incorrect assessments of habitat importance leading to inappropriate management strategies. We took a two-stage approach to identifying critical nesting and brood-rearing habitat for the endangered Greater Sage-Grouse (Centrocercus urophasianus) in Alberta at a landscape scale. First, we used logistic regression to develop spatial models predicting the relative probability of use (occurrence) for Sage-Grouse nests and broods. Secondly, we used Cox proportional hazards survival models to identify the most risky habitats across the landscape. We combined these two approaches to identify Sage-Grouse habitats that pose minimal risk of failure (source habitats) and attractive sink habitats that pose increased risk (ecological traps). Our models showed that Sage-Grouse select for heterogeneous patches of moderate sagebrush cover (quadratic relationship) and avoid anthropogenic edge habitat for nesting. Nests were more successful in heterogeneous habitats, but nest success was independent of anthropogenic features. Similarly, broods selected heterogeneous high-productivity habitats with sagebrush while avoiding human developments, cultivated cropland, and high densities of oil wells. Chick mortalities tended to occur in proximity to oil and gas developments and along riparian habitats. For nests and broods, respectively, approximately 10% and 5% of the study area was considered source habitat, whereas 19% and 15% of habitat was attractive sink habitat. Limited source habitats appear to be the main reason for poor nest success (39%) and low chick survival (12%). Our habitat models identify areas of protection priority and areas that require immediate management attention to enhance recruitment to secure the viability of this population. This novel
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The minimum area requirements (MAR) for giant panda: an empirical study.
Qing, Jing; Yang, Zhisong; He, Ke; Zhang, Zejun; Gu, Xiaodong; Yang, Xuyu; Zhang, Wen; Yang, Biao; Qi, Dunwu; Dai, Qiang
2016-12-08
Habitat fragmentation can reduce population viability, especially for area-sensitive species. The Minimum Area Requirements (MAR) of a population is the area required for the population's long-term persistence. In this study, the response of occupancy probability of giant pandas against habitat patch size was studied in five of the six mountain ranges inhabited by giant panda, which cover over 78% of the global distribution of giant panda habitat. The probability of giant panda occurrence was positively associated with habitat patch area, and the observed increase in occupancy probability with patch size was higher than that due to passive sampling alone. These results suggest that the giant panda is an area-sensitive species. The MAR for giant panda was estimated to be 114.7 km 2 based on analysis of its occupancy probability. Giant panda habitats appear more fragmented in the three southern mountain ranges, while they are large and more continuous in the other two. Establishing corridors among habitat patches can mitigate habitat fragmentation, but expanding habitat patch sizes is necessary in mountain ranges where fragmentation is most intensive.
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Identification of mosquito larval habitats in high resolution satellite data
NASA Astrophysics Data System (ADS)
Kiang, Richard K.; Hulina, Stephanie M.; Masuoka, Penny M.; Claborn, David M.
2003-09-01
Mosquito-born infectious diseases are a serious public health concern, not only for the less developed countries, but also for developed countries like the U.S. Larviciding is an effective method for vector control and adverse effects to non-target species are minimized when mosquito larval habitats are properly surveyed and treated. Remote sensing has proven to be a useful technique for large-area ground cover mapping, and hence, is an ideal tool for identifying potential larval habitats. Locating small larval habitats, however, requires data with very high spatial resolution. Textural and contextual characteristics become increasingly evident at higher spatial resolution. Per-pixel classification often leads to suboptimal results. In this study, we use pan-sharpened Ikonos data, with a spatial resolution approaching 1 meter, to classify potential mosquito larval habitats for a test site in South Korea. The test site is in a predominantly agricultural region. When spatial characteristics were used in conjunction with spectral data, reasonably good classification accuracy was obtained for the test site. In particular, irrigation and drainage ditches are important larval habitats but their footprints are too small to be detected with the original spectral data at 4-meter resolution. We show that the ditches are detectable using automated classification on pan-sharpened data.
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Bird communities of natural and modified habitats in Panama
Petit, L.J.; Petit, D.R.; Christian, D.G.; Powell, Hugo D.W.
1999-01-01
enhancement of agricultural and developed lands as wildlife habitat. To understand the true conservation value of these modified lands will require examination not only of numbers but also of the types of species supported by these habitats, their reproductive output and survival rates.
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Li, Donglai; Liu, Yu; Sun, Xinghai; Lloyd, Huw; Zhu, Shuyu; Zhang, Shuyan; Wan, Dongmei; Zhang, Zhengwang
2017-11-30
The Endangered Red-crowned Crane (Grus japonensis) is one of the most culturally iconic and sought-after species by wildlife tourists. Here we investigate how the presence of tourists influence the vigilance behaviour of cranes foraging in Suaeda salsa salt marshes and S. salsa/Phragmites australis mosaic habitat in the Yellow River Delta, China. We found that both the frequency and duration of crane vigilance significantly increased in the presence of wildlife tourists. Increased frequency in crane vigilance only occurred in the much taller S. salsa/P. australis mosaic vegetation whereas the duration of vigilance showed no significant difference between the two habitats. Crane vigilance declined with increasing distance from wildlife tourists in the two habitats, with a minimum distance of disturbance triggering a high degree of vigilance by cranes identified at 300 m. The presence of wildlife tourists may represent a form of disturbance to foraging cranes but is habitat dependent. Taller P. australis vegetation serves primarily as a visual obstruction for cranes, causing them to increase the frequency of vigilance behaviour. Our findings have important implications for the conservation of the migratory red-crowned crane population that winters in the Yellow River Delta and can help inform visitor management.
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Reforestation to enhance Appalachian mined lands as habitat for terrestrial wildlife
Wood, Petra B.; Larkin, Jeff; Mizel, Jeremy; Zipper, Carl E.; Angel, Patrick
2013-01-01
Surface mining is widespread throughout the Appalachian coalfield, a region with extensive forests that are rich in wildlife. Game species for hunting, non-game wildlife species, and other organisms are important contributors to sustainable and productive ecosystems. Although small breaks in the forest canopy are important to wildlife diversity, most native Appalachian wildlife species require primarily forested habitats. This Forest Reclamation Advisory provides guidance on reforestation practices to provide high quality habitat for native forest wildlife on Appalachian coal mines.
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Habitat modeling and genetic signatures of postglacial recolonization for tidal estuaries
NASA Astrophysics Data System (ADS)
Dolby, G. A.; Jacobs, D. K.
2014-12-01
Pleistocene glacial cycles are a foremost influence on the genetic diversity and species distribution patterns observed today. Though much work has centered on biotic response to such climatic forcing, little of it has regarded estuarine or other aquatic coastal taxa whose habitat formation is a function of sea level, hydrography, and coastal geomorphology. These physical parameters required for habitat formation suggest that glacial cycles impart a significant effect on such taxa through glacially driven eustatic changes. Additionally, the steepened coastline and rainfall-limited Mediterranean climate suggest limited glacial habitat for estuarine species in southern and Baja California. Here we present GIS modeled habitat for tidal estuaries for three co-distributed estuarine fishes (Gillichthys mirabilis, Quietula y-cauda, Fundulus parvipinnis) since the last glacial maximum. Parameterization of sea level and slope enables biologically relevant temporal resolution of near-millennial scale. At lowstand our approach reveals two refuges along the coast at 1000km distance from each other, with habitat rapidly increasing 15 - 12 ka during meltwater pulse 1A. Habitat area peaked in the early Holocene and began decreasing with the current stillstand roughly 7 ka, probably as a result of coastal maturation towards less tidal systems. To target the postglacial recolonization process we applied discriminant function analysis to highly polymorphic microsatellite data to partition out the alleles associated with refuges identified a priori by habitat modeling. The frequencies of these alleles were calculated for all individuals at intervening populations and regressed against geographic distance. This analysis revealed nonlinear mixing curves, suggesting uneven allelic mixing efficiency along the coastline, perhaps as a result of differential habitat origination times as indicated by the habitat models. These results highlight the dynamism of estuarine habitat in recent
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Mark S. Wipfli
2005-01-01
This study examined the fluvial transport of invertebrates (aquatic and terrestrial) and coarse organic detritus from forested - headwaters in alternatives-to-clearcutting (ATC) harvest units to aquatic habitats downstream in the coastal mountains of southeastern Alaska. Fifty small streams (mean discharge 2.7 Ls-1, range 0.1-128.1 Ls-...
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Habitat Effects on the Breeding Performance of Three Forest-Dwelling Hawks.
Björklund, Heidi; Valkama, Jari; Tomppo, Erkki; Laaksonen, Toni
2015-01-01
Habitat loss causes population declines, but the mechanisms are rarely known. In the European Boreal Zone, loss of old forest due to intensive forestry is suspected to cause declines in forest-dwelling raptors by reducing their breeding performance. We studied the boreal breeding habitat and habitat-associated breeding performance of the northern goshawk (Accipiter gentilis), common buzzard (Buteo buteo) and European honey buzzard (Pernis apivorus). We combined long-term Finnish bird-of-prey data with multi-source national forest inventory data at various distances (100-4000 m) around the hawk nests. We found that breeding success of the goshawk was best explained by the habitat within a 2000-m radius around the nests; breeding was more successful with increasing proportions of old spruce forest and water, and decreasing proportions of young thinning forest. None of the habitat variables affected significantly the breeding success of the common buzzard or the honey buzzard, or the brood size of any of the species. The amount of old spruce forest decreased both around goshawk and common buzzard nests and throughout southern Finland in 1992-2010. In contrast, the area of young forest increased in southern Finland but not around hawk nests. We emphasize the importance of studying habitats at several spatial and temporal scales to determine the relevant species-specific scale and to detect environmental changes. Further effort is needed to reconcile the socioeconomic and ecological functions of forests and habitat requirements of old forest specialists.
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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...
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Assessing critical habitat: Evaluating the relative contribution of habitats to population
A principal challenge of species conservation is to identify the specific habitats that are essential for long-term persistence or recovery of imperiled species. However, many approaches to identifying important habitats do not provide direct insight into the contribution of hab...
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Habitat and conservation status of the beaver in the Sierra San Luis Sonora, Mexico
Karla Pelz Serrano; Eduardo Ponce Guevara; Carlos A. Lopez Gonzalez
2005-01-01
The status of beaver (Castor canadensis) in northeastern Sonora, Mexico, is uncertain. We surveyed the Cajon Bonito River to assess the beaverâs status and habitat and found five colonies. Limiting factors appear to be pollution due to animal waste, deforestation of riparian trees, and human exploitation. Beavers did not appear to require habitat...
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Assessment and management of dead-wood habitat
Hagar, Joan
2007-01-01
Oregon and Washington, approximately 150 species of wildlife are reported to use dead wood in forests (O’Neil et al., 2001). Forty-seven sensitive and special-status species are associated with dead wood (Appendix A). These are key species for management consideration because concern over small or declining populations is often related to loss of suitable dead-wood habitat (Marshall et al., 1996). Primary excavators (woodpeckers) also are often the focus of dead-wood management, because they perform keystone functions in forest ecosystems by creating cavities for secondary cavity-nesters (Martin and Eadie, 1999; Aubry and Raley, 2002). A diverse guild of secondary cavity-users (including swallows, bluebirds, several species of ducks and owls, ash-throated flycatcher, flying squirrel, bats, and many other species) is unable to excavate dead wood, and therefore relies on cavities created by woodpeckers for nesting sites. Suitable nest cavities are essential for reproduction, and their availability limits population size (Newton, 1994). Thus, populations of secondary cavity-nesters are tightly linked to the habitat requirements of primary excavators. Although managers often focus on decaying wood as habitat for wildlife, the integral role dead wood plays in ecological processes is an equally important consideration for management. Rose et al. (2001) provide a thorough review of the ecological functions of dead wood in Pacific Northwest forests, briefly summarized here. Decaying wood functions in: soil development and productivity, nutrient cycling, nitrogen fixation, and carbon storage. From ridge tops, to headwater streams, to estuaries and coastal marine ecosystems, decaying wood is fundamental to diverse terrestrial and aquatic food webs. Wildlife species that use dead wood for cover or feeding are linked to these ecosystem processes through a broad array of functional roles, including facilitation of decay and trophic interactions with other organisms (Marcot, 2002
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ERIC Educational Resources Information Center
Hein, Annamae J.
2011-01-01
The Habitat Project is a multiday, differentiated, interdisciplinary environmental science lesson that incorporates skill-building and motivational strategies to internalize ecosystem vocabulary. Middle school students research an animal, display its physical characteristics on a poster, build a three-dimensional habitat and present their work…
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Describing Willow Flycatcher habitats: scale perspectives and gender differences
Sedgwick, James A.; Knopf, Fritz L.
1992-01-01
We compared habitat characteristics of nest sites (female-selected sites) and song perch sites (male-selected sites) with those of sites unused by Willow Flycatchers (Empidonax traillii) at three different scales of vegetation measurement: (1) microplot (central willow [Salix spp.] bush and four adjacent bushes); (2) mesoplot (0.07 ha); and, (3) macroplot (flycatcher territory size). Willow Flycatchers exhibited vegetation preferences at all three scales. Nest sites were distinguished by high willow density and low variability in willow patch size and bush height. Song perch sites were characterized by large central shrubs, low central shrub vigor, and high variability in shrub size. Unused sites were characterized by greater distances between willows and willow patches, less willow coverage, and a smaller riparian zone width than either nest or song perch sites. At all scales, nest sites were situated farther from unused sites in multivariate habitat space than were song perch sites, suggesting (1) a correspondence among scales in their ability to describe Willow Flycatcher habitat, and (2) females are more discriminating in habitat selection than males. Microhabitat differences between male-selected (song perch) and female-selected (nest) sites were evident at the two smaller scales; at the finest scale, the segregation in habitat space between male-selected and female-selected sites was greater than that between male-selected and unused sites. Differences between song perch and nest sites were not apparent at the scale of flycatcher territory size, possibly due to inclusion of (1) both nest and song perch sites, (2) defended, but unused habitat, and/or (3) habitat outside of the territory, in larger scale analyses. The differences between nest and song perch sites at the finer scales reflect their different functions (e.g., nest concealment and microclimatic requirements vs. advertising and territorial defense, respectively), and suggest that the exclusive use
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Habitat Suitability Index Models: Laughing gull
Zale, Alexander V.; Mulholland, Rosemarie
1985-01-01
A review and synthesis of existing information were used to develop a habitat model for laughing gull (Larus atricilla). The model is scaled to produce an index of habitat suitability between 0 (unsuitable habitat) and 1.0 (optimally suitable habitat) for areas along the Gulf of Mexico coast. Habitat suitability indices are designed for use with the Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service. Guidelines for application of the model and techniques for measuring model variables are described.
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Baker, Duncan G L; Eddy, Tyler D; McIver, Reba; Schmidt, Allison L; Thériault, Marie-Hélène; Boudreau, Monica; Courtenay, Simon C; Lotze, Heike K
2016-01-01
Coastal ecosystems are among the most productive yet increasingly threatened marine ecosystems worldwide. Particularly vegetated habitats, such as eelgrass (Zostera marina) beds, play important roles in providing key spawning, nursery and foraging habitats for a wide range of fauna. To properly assess changes in coastal ecosystems and manage these critical habitats, it is essential to develop sound monitoring programs for foundation species and associated assemblages. Several survey methods exist, thus understanding how different methods perform is important for survey selection. We compared two common methods for surveying macrofaunal assemblages: beach seine netting and underwater visual census (UVC). We also tested whether assemblages in shallow nearshore habitats commonly sampled by beach seines are similar to those of nearby eelgrass beds often sampled by UVC. Among five estuaries along the Southern Gulf of St. Lawrence, Canada, our results suggest that the two survey methods yield comparable results for species richness, diversity and evenness, yet beach seines yield significantly higher abundance and different species composition. However, sampling nearshore assemblages does not represent those in eelgrass beds despite considerable overlap and close proximity. These results have important implications for how and where macrofaunal assemblages are monitored in coastal ecosystems. Ideally, multiple survey methods and locations should be combined to complement each other in assessing the entire assemblage and full range of changes in coastal ecosystems, thereby better informing coastal zone management.
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Restoring and Maintaining Riparian Habitat on Private Pastureland
Nancy Reichard
1989-01-01
Protecting riparian habitat from livestock grazing on private land is a complex task that requires paying attention to sociological and economic as well as physical and biological factors. Six livestock exclusion fencing projects on private property in northwestern California are described. The importance of long term maintenance and the need for landowner incentives...
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Hydrologic and water-quality rehabilitation of environments for suitable fish habitat
NASA Astrophysics Data System (ADS)
Zhao, C. S.; Yang, S. T.; Xiang, H.; Liu, C. M.; Zhang, H. T.; Yang, Z. L.; Zhang, Y.; Sun, Y.; Mitrovic, S. M.; Yu, Q.; Lim, R. P.
2015-11-01
Aquatic ecological rehabilitation is attracting increasing public and research attention, but without knowledge of the responses of aquatic species to their habitats the success of habitat restoration is uncertain. Thus efficient study of species response to habitat, through which to prioritize the habitat factors influencing aquatic ecosystems, is highly important. However many current models have too high requirement for assemblage information and have great bias in results due to consideration of only the species' attribute of presence/absence, abundance or biomass, thus hindering the wider utility of these models. This paper, using fish as a case, presents a framework for identification of high-priority habitat factors based on the responses of aquatic species to their habitats, using presence/absence, abundance and biomass data. This framework consists of four newly developed sub-models aiming to determine weightings for the evaluation of species' contributions to their communities, to quantitatively calculate an integrated habitat suitability index for multi-species based on habitat factors, to assess the suitable probability of habitat factors and to assess the rehabilitation priority of habitat factors. The framework closely links hydrologic, physical and chemical habitat factors to fish assemblage attributes drawn from monitoring datasets on hydrology, water quality and fish assemblages at a total of 144 sites, where 5084 fish were sampled and tested. Breakpoint identification techniques based on curvature in cumulated dominance along with a newly developed weighting calculation model based on theory of mass systems were used to help identify the dominant fish, based on which the presence and abundance of multiple fish were normalized to estimate the integrated habitat suitability index along gradients of various factors, based on their variation with principal habitat factors. Then, the appropriate probability of every principal habitat factor was
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Influence of habitat characteristics on shore-spawning kokanee
Whitlock, Steven L.; Quist, Michael C.; Dux, Andrew M.
2014-01-01
Sockeye Salmon Oncorhynchus nerka and kokanee (lacustrine Sockeye Salmon) commonly spawn in both lentic and lotic environments; however, the habitat requirements of shore spawners are virtually unknown relative to those of stream spawners. A laboratory experiment and an in situ incubation study were conducted to better understand the influence of habitat characteristics on the shoreline incubation success of kokanee. The laboratory experiment assessed kokanee intragravel survival, fry emergence, and fry condition in response to eight substrate treatments. The in situ study, conducted at three major shoreline spawning sites in Lake Pend Oreille, Idaho, evaluated the effect of depth, substrate composition, dissolved oxygen, shoreline slope, and groundwater on intragravel survival. Substrate size composition was generally a poor predictor of survival in both the laboratory experiment and in situ study; although, fry condition and counts of emerged fry in the laboratory were lowest for the substrate treatment that had the highest proportion of fine sediment. Results of the in situ study suggest that groundwater flow plays an important role in enhancing intragravel survival in habitats generally considered unsuitable for spawning.
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Discerning fish - habitat associations at a variety of spatial scales is relevant to evaluating stressor responses and assessment protocols in Great Lakes coastal wetlands. NMDS ordination of electrofishing catch-per-effort data identified an overriding influence of geography an...
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Sherfy, Mark H.; Stucker, Jennifer H.; Anteau, Michael J.
2009-01-01
Habitat conditions are one of the most important factors determining distribution and productivity of least terns (Sternula antillarum) and piping plovers (Charadrius melodus) in the upper Missouri River system (Ziewitz and others, 1992; Kruse and others, 2002). Habitat conditions are known to change within and among seasons in response to variation in river flows, weather conditions, and management actions targeted at providing for the needs of terns and plovers. Although these principles are generally agreed upon, there is little empirical information available on the quantity and quality of tern and plover habitats in this system, particularly with reference to the major life history events that must be supported (egg laying, incubation, and brood rearing). Habitat requirements for these events are composed of two major categories: nesting and foraging habitat. In the case of piping plovers, these two requirements must occur on the same area because plover chicks are constrained to foraging near nesting sites prior to fledging (Knetter and others, 2002; Haffner, 2005). In contrast, least terns chicks are fed by the adults, allowing food procurement for broods to occur outside the immediate nesting area; however, food resources must be close enough to nesting locations to minimize foraging time. The complexity and dynamics of the upper Missouri River system introduce considerable uncertainty into how best to manage tern and plover habitats, and how best to evaluate the effectiveness of this management. An extensive program of habitat monitoring will be needed to address this complexity and support the management of least terns and piping plovers under the Missouri River Recovery Program. These needs are being addressed, in part, through a program of habitat creation and management targeted at improving quality and quantity of habitats for terns and plovers. Given the momentum of these projects and their associated costs, it is imperative that the capacity be
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Proceedings of a workshop on fish habitat suitability index models
Terrell, James W.
1984-01-01
One of the habitat-based methodologies for impact assessment currently in use by the U.S. Fish and Wildlife Service is the Habitat Evaluation Procedures (HEP) (U.S. Fish and Wildlife Service 1980). HEP is based on the assumption that the quality of an area as wildlife habitat at a specified target year can be described by a single number, called a Habitat Suitability Index (HSI). An HSI of 1.0 represents optimum habitat: an HSI of 0.0 represents unsuitable habitat. The verbal or mathematical rules by which an HSI is assigned to an area are called an HSI model. A series of Habitat Suitability Index (HSI) models, described by Schamberger et al. (1982), have been published to assist users in applying HEP. HSI model building approaches are described in U.S. Fish and Wildlife Service (1981). One type of HSI model described in detail requires the development of Suitability Index (SI) graphs for habitat variables believed to be important for the growth, survival, standing crop, or other measure of well-being for a species. Suitability indices range from 0 to 1.0, with 1.0 representing optimum conditions for the variable. When HSI models based on suitability indices are used, habitat variable values are measured, or estimated, and converted to SI's through the use of a Suitability Index graph for each variable. Individual SI's are aggregated into an HSI. Standard methods for testing this type of HSI model did not exist at the time the studies reported in this document were performed. A workshop was held in Fort Collins, Colorado, February 14-15, 1983, that brought together biologists experienced in the use, development, and testing of aquatic HSI models, in an effort to address the following objectives: (1) review the needs of HSI model users; (2) discuss and document the results of aquatic HSI model tests; and (3) provide recommendations for the future development, testing, modification, and use of HSI models. Individual presentations, group discussions, and group
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Korpimäki, Erkki; Villers, Alexandre; Selonen, Vesa
2018-01-01
Habitat choice often entails trade-offs between food availability and predation risk. Understanding the distribution of individuals in space thus requires that both habitat characteristics and predation risk are considered simultaneously. Here, we studied the nest box use of two arboreal squirrels who share preferred habitat with their main predators. Nocturnal Ural owls (Strix uralensis) decreased occurrence of night-active flying squirrels (Pteromys volans) and diurnal goshawks (Accipiter gentilis) that of day-active red squirrels (Sciurus vulgaris). Unexpectedly, the amount of preferred habitat had no effect on nest box use, but, surprisingly, both squirrel species seemed to benefit from close proximity to agricultural fields and red squirrels to urban areas. We found no evidence of trade-off between settling in a high-quality habitat and avoiding predators. However, the amount of poor-quality young pine forests was lower in occupied sites where goshawks were present, possibly indicating habitat specific predation on red squirrels. The results suggest that erecting nest boxes for Ural owls should be avoided in the vicinity of flying squirrel territories in order to conserve the near threatened flying squirrels. Our results also suggest that flying squirrels do not always need continuous old forests, and hence the currently insufficient conservation practices could be improved with reasonable increases in the areas left untouched around their nests. The results of this study demonstrate the importance of taking into account both habitat requirements and predation risk as well as their interactive effects when modeling the occupancy of threatened animal species and planning their conservation. PMID:29596438
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Hjältén, Joakim; Stenbacka, Fredrik; Pettersson, Roger B; Gibb, Heloise; Johansson, Therese; Danell, Kjell; Ball, John P; Hilszczański, Jacek
2012-01-01
Restoration of habitats is critically important in preventing full realization of the extinction debt owed as a result of anthropogenic habitat destruction. Although much emphasis has been placed on macrohabitats, suitable microhabitats are also vital for the survival of most species. The aim of this large-scale field experiment was to evaluate the relative importance of manipulated microhabitats, i.e., dead wood substrates of spruce (snags, and logs that were burned, inoculated with wood fungi or shaded) and macrohabitats, i.e., stand types (clear-cuts, mature managed forests, and forest reserves) for species richness, abundance and assemblage composition of all saproxylic and red-listed saproxylic beetles. Beetles were collected in emergence traps in 30 forest stands in 2001, 2003, 2004 and 2006. More individuals emerged from snags and untreated logs than from burned and shaded logs, but species richness did not differ among substrates. Assemblage composition differed among substrates for both all saproxylics and red-listed saproxylic species, mainly attributed to different assemblage composition on snags. This suggests that the practise of leaving snags for conservation purposes should be complemented with log supplementation. Clear-cuts supported fewer species and different assemblages from mature managed forests and reserves. Neither abundance, nor species richness or assemblage composition differed between reserves and mature managed forests. This suggests that managed stands subjected to selective cutting, not clear-felling, maintain sufficient old growth characteristics and continuity to maintain more or less intact assemblages of saproxylic beetles. Thus, alternative management methods, e.g., continuity forestry should be considered for some of these stands to maintain continuity and conservation values. Furthermore, the significantly higher estimated abundance per ha of red-listed beetles in reserves underlines the importance of reserves for maintaining
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Ossola, Alessandro; Hahs, Amy Kristin; Livesley, Stephen John
2015-08-15
Urban ecosystems have traditionally been considered to be pervious features of our cities. Their hydrological properties have largely been investigated at the landscape scale and in comparison with other urban land use types. However, hydrological properties can vary at smaller scales depending upon changes in soil, surface litter and vegetation components. Management practices can directly and indirectly affect each of these components and the overall habitat complexity, ultimately affecting hydrological processes. This study aims to investigate the influence that habitat components and habitat complexity have upon key hydrological processes and the implications for urban habitat management. Using a network of urban parks and remnant nature reserves in Melbourne, Australia, replicate plots representing three types of habitat complexity were established: low-complexity parks, high-complexity parks, and high-complexity remnants. Saturated soil hydraulic conductivity in low-complexity parks was an order of magnitude lower than that measured in the more complex habitat types, due to fewer soil macropores. Conversely, soil water holding capacity in low-complexity parks was significantly higher compared to the two more complex habitat types. Low-complexity parks would generate runoff during modest precipitation events, whereas high-complexity parks and remnants would be able to absorb the vast majority of rainfall events without generating runoff. Litter layers on the soil surface would absorb most of precipitation events in high-complexity parks and high-complexity remnants. To minimize the incidence of stormwater runoff from urban ecosystems, land managers could incrementally increase the complexity of habitat patches, by increasing canopy density and volume, preserving surface litter and maintaining soil macropore structure. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Kweka, Eliningaya J; Zhou, Guofa; Munga, Stephen; Lee, Ming-Chieh; Atieli, Harrysone E; Nyindo, Mramba; Githeko, Andrew K; Yan, Guiyun
2012-01-01
Larval control is of paramount importance in the reduction of malaria vector abundance and subsequent disease transmission reduction. Understanding larval habitat succession and its ecology in different land use managements and cropping systems can give an insight for effective larval source management practices. This study investigated larval habitat succession and ecological parameters which influence larval abundance in malaria epidemic prone areas of western Kenya. A total of 51 aquatic habitats positive for anopheline larvae were surveyed and visited once a week for a period of 85 weeks in succession. Habitats were selected and identified. Mosquito larval species, physico-chemical parameters, habitat size, grass cover, crop cycle and distance to nearest house were recorded. Polymerase chain reaction revealed that An. gambiae s.l was the most dominant vector species comprised of An.gambiae s.s (77.60%) and An.arabiensis (18.34%), the remaining 4.06% had no amplification by polymerase chain reaction. Physico-chemical parameters and habitat size significantly influenced abundance of An. gambiae s.s (P = 0.024) and An. arabiensis (P = 0.002) larvae. Further, larval species abundance was influenced by crop cycle (P≤0.001), grass cover (P≤0.001), while distance to nearest houses significantly influenced the abundance of mosquito species larvae (r = 0.920;P≤0.001). The number of predator species influenced mosquito larval abundance in different habitat types. Crop weeding significantly influenced with the abundance of An.gambiae s.l (P≤0.001) when preceded with fertilizer application. Significantly higher anopheline larval abundance was recorded in habitats in pasture compared to farmland (P = 0.002). When habitat stability and habitat types were considered, hoof print were the most productive followed by disused goldmines. These findings suggest that implementation of effective larval control programme should be targeted with larval habitats
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Seasonal variation in habitat use of juvenile Steelhead in a tributary of Lake Ontario
Studdert, Emily W.; Johnson, James H.
2015-01-01
We examined seasonal-habitat use by subyearling and yearling Oncorhynchus mykiss (Rainbow Trout or Steelhead) in Trout Brook, a tributary of the Salmon River, NY. We determined daytime fish-habitat use and available habitat during August and October of the same year and observed differences in habitat selection among year classes. Water depth and cover played the greatest role in Steelhead habitat use. During summer and autumn, we found yearling Steelhead in areas with deeper water and more cover than where we observed subyearling Steelhead. Both year classes sought out areas with abundant cover during both seasons; this habitat was limited within the stream reach. Subyearling Steelhead were associated with more cover during autumn, even though available cover within the stream reach was greater during summer. Principal component analysis showed that variation in seasonal-habitat use was most pronounced for subyearling Steelhead and that yearling Steelhead were more selective in their habitat use than subyearling Steelhead. The results of this study contribute to a greater understanding of how this popular sportfish is adapting to a new environment and the factors that may limit juvenile Steelhead survival. Our findings provide valuable new insights into the seasonal-habitat requirements of subyearling and yearling Steelhead that can be used by fisheries managers to enhance and protect the species throughout the Great Lakes region.
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Lambert, Charlotte; Mannocci, Laura; Lehodey, Patrick; Ridoux, Vincent
2014-01-01
To date, most habitat models of cetaceans have relied on static and oceanographic covariates, and very few have related cetaceans directly to the distribution of their prey, as a result of the limited availability of prey data. By simulating the distribution of six functional micronekton groups between the surface and ≃1,000 m deep, the SEAPODYM model provides valuable insights into prey distributions. We used SEAPODYM outputs to investigate the habitat of three cetacean guilds with increasing energy requirements: sperm and beaked whales, Globicephalinae and Delphininae. We expected High Energy Requirements cetaceans to preferentially forage in habitats of high prey biomass and/or production, where they might easily meet their high energetic needs, and Low Energy Requirements cetaceans to forage in habitats of either high or low prey biomass and/or production. Cetacean sightings were collected from dedicated aerial surveys in the South West Indian Ocean (SWIO) and French Polynesia (FP). We examined cetacean densities in relation to simulated distributions of their potential prey using Generalised Additive Models and predicted their habitats in both regions. Results supported their known diving abilities, with Delphininae mostly related to prey present in the upper layers of the water column, and Globicephalinae and sperm and beaked whales also related to prey present in deeper layers. Explained deviances ranged from 9% for sperm and beaked whales in the SWIO to 47% for Globicephalinae in FP. Delphininae and Globicephalinae appeared to select areas where high prey biomass and/or production were available at shallow depths. In contrast, sperm and beaked whales showed less clear habitat selection. Using simulated prey distributions as predictors in cetacean habitat models is crucial to understand their strategies of habitat selection in the three dimensions of the ocean. PMID:25162643
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Habitat Suitability Index Models: Hairy woodpecker
Sousa, Patrick J.
1987-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the hairy woodpecker (Picoides villosus). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
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Habitat Suitability Index Models: Snapping turtle
Graves, Brent M.; Anderson, Stanley H.
1987-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the snapping turtle (Chelydra serpentina). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) and 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
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Habitat Suitability Index Models: Spotted owl
Laymon, Stephen A.; Salwasser, Hal; Barrett, Reginald H.
1985-01-01
A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the spotted owl (Strix occidentalis). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.
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The Single Habitat Module Concept for Exploration - Mission Planning and Mass Estimates
NASA Technical Reports Server (NTRS)
Chambliss, Joe; Studak, J. W.
2013-01-01
The Single Habitat Module (SHM) concept approach to the infrastructure and conduct of exploration missions combines many of new promising technologies with a central concept of mission architectures that use a single habitat module for all phases of an exploration mission. Integrating mission elements near Earth and fully fueling them prior to departure of the vicinity of Earth provides the capability of using the single habitat both in transit to/from an exploration destination and while exploring the destination. The concept employs the capability to return the habitat and interplanetary propulsion system to Earth vicinity so that those elements can be reused on subsequent exploration missions. This paper provides an overview of the SHM concept and the advantages it provides. A summary of calculations of the mass of the habitat propulsion system (HPS) needed to get the habitat from Low Mars Orbit (LMO) to the surface and back to LMO and an overview of trajectory and mission mass assessments related to use of a high specific impulse space based propulsion system is provided. Those calculations lead to the conclusion that the SHM concept can significantly reduce the mass required and streamline mission operations to explore Mars (and thus all exploration destinations).
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The Single Habitat Module Concept for Exploration - Mission Planning and Mass Estimates
NASA Technical Reports Server (NTRS)
Chambliss, Joe; Studak, J. W.
2013-01-01
The Single Habitat Module (SHM) concept approach to the infrastructure and conduct of exploration missions combines many new promising technologies with a central concept of mission architectures that use a single habitat module for all phases of an exploration mission. Integrating mission elements near Earth and fully fueling them prior to departure of the vicinity of Earth provides the capability of using the single habitat both in transit to/from an exploration destination and while exploring the destination. The concept employs the capability to return the habitat and interplanetary propulsion system to Earth vicinity so that those elements can be reused on subsequent exploration missions. This paper provides an overview of the SHM concept and the advantages it provides. The paper also provides a summary of calculations of the mass of the Habitat Propulsion System (HPS) needed to get the habitat from low-Mars orbit (LMO) to the surface and back to LMO, and an overview of trajectory and mission mass assessments related to use of a high specific impulse space-based propulsion system. Those calculations led to the conclusion that the SHM concept results in low total mass required and streamlines mission operations to explore Mars (or other exploration destinations).
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Feral Cats Are Better Killers in Open Habitats, Revealed by Animal-Borne Video.
McGregor, Hugh; Legge, Sarah; Jones, Menna E; Johnson, Christopher N
2015-01-01
One of the key gaps in understanding the impacts of predation by small mammalian predators on prey is how habitat structure affects the hunting success of small predators, such as feral cats. These effects are poorly understood due to the difficulty of observing actual hunting behaviours. We attached collar-mounted video cameras to feral cats living in a tropical savanna environment in northern Australia, and measured variation in hunting success among different microhabitats (open areas, dense grass and complex rocks). From 89 hours of footage, we recorded 101 hunting events, of which 32 were successful. Of these kills, 28% were not eaten. Hunting success was highly dependent on microhabitat structure surrounding prey, increasing from 17% in habitats with dense grass or complex rocks to 70% in open areas. This research shows that habitat structure has a profound influence on the impacts of small predators on their prey. This has broad implications for management of vegetation and disturbance processes (like fire and grazing) in areas where feral cats threaten native fauna. Maintaining complex vegetation cover can reduce predation rates of small prey species from feral cat predation.
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Feral Cats Are Better Killers in Open Habitats, Revealed by Animal-Borne Video
McGregor, Hugh; Legge, Sarah; Jones, Menna E.; Johnson, Christopher N.
2015-01-01
One of the key gaps in understanding the impacts of predation by small mammalian predators on prey is how habitat structure affects the hunting success of small predators, such as feral cats. These effects are poorly understood due to the difficulty of observing actual hunting behaviours. We attached collar-mounted video cameras to feral cats living in a tropical savanna environment in northern Australia, and measured variation in hunting success among different microhabitats (open areas, dense grass and complex rocks). From 89 hours of footage, we recorded 101 hunting events, of which 32 were successful. Of these kills, 28% were not eaten. Hunting success was highly dependent on microhabitat structure surrounding prey, increasing from 17% in habitats with dense grass or complex rocks to 70% in open areas. This research shows that habitat structure has a profound influence on the impacts of small predators on their prey. This has broad implications for management of vegetation and disturbance processes (like fire and grazing) in areas where feral cats threaten native fauna. Maintaining complex vegetation cover can reduce predation rates of small prey species from feral cat predation. PMID:26288224
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NASA Astrophysics Data System (ADS)
De la Torriente, A.; Serrano, A.; Fernández-Salas, L. M.; García, M.; Aguilar, R.
2018-05-01
High habitat diversity was observed on the Seco de los Olivos Seamount (SW Mediterranean Sea), a Site of Community Importance belonging to the Spanish marine Natura 2000 Network. Thirteen epibenthic habitats were identified by analysing 55 Remotely Operated Vehicle (ROV) transects from 76 m to 700 m depth and derived data from multibeam bathymetry and high resolution seismic profiles. Habitat identification was based on a combination of assemblages of habitat-forming species and the environmental characteristics supporting their distribution. Depth and slope were identified as the main significant factors structuring epibenthic assemblages. The high diversity and patchiness of habitats found on the Seco de los Olivos Seamount can be explained by the high environmental variability resulting from its wide geomorphologic diversity, where flat summits, steep flanks, rocky outcrops and sedimentary moats are combined. The distribution of benthic habitats at this seamount is likely a combination of suitable ecological conditions, local recruitment, feeding strategies and attachment mechanisms. Knowledge on the occurrence of habitats in areas of natural importance is crucial to species and habitats conservation and to develop proper monitoring and management programs aimed at fulfilling European regulation requirements.
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2013-07-01
endangered species and their associated habitats as an important goal of ecosystem restoration and management. There is no doubt the determination of...accounting process developed to appraise habitat suitability for fish and wildlife species in response to potential change (USFWS 1980a-c). HEP is an... habitat to a species is likely to exhibit strong thresholds below which the habitat is usually unsuitable and above which further changes in habitat
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The minimum area requirements (MAR) for giant panda: an empirical study
Qing, Jing; Yang, Zhisong; He, Ke; Zhang, Zejun; Gu, Xiaodong; Yang, Xuyu; Zhang, Wen; Yang, Biao; Qi, Dunwu; Dai, Qiang
2016-01-01
Habitat fragmentation can reduce population viability, especially for area-sensitive species. The Minimum Area Requirements (MAR) of a population is the area required for the population’s long-term persistence. In this study, the response of occupancy probability of giant pandas against habitat patch size was studied in five of the six mountain ranges inhabited by giant panda, which cover over 78% of the global distribution of giant panda habitat. The probability of giant panda occurrence was positively associated with habitat patch area, and the observed increase in occupancy probability with patch size was higher than that due to passive sampling alone. These results suggest that the giant panda is an area-sensitive species. The MAR for giant panda was estimated to be 114.7 km2 based on analysis of its occupancy probability. Giant panda habitats appear more fragmented in the three southern mountain ranges, while they are large and more continuous in the other two. Establishing corridors among habitat patches can mitigate habitat fragmentation, but expanding habitat patch sizes is necessary in mountain ranges where fragmentation is most intensive. PMID:27929520
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Brian G. Tavernia; Mark D. Nelson; Michael E. Goerndt; Brian F. Walters; Chris Toney
2013-01-01
Large-scale and long-term habitat management plans are needed to maintain the diversity of habitat classes required by wildlife species. Planning efforts would benefit from assessments of potential climate and land-use change effects on habitats. We assessed climate and land-use driven changes in areas of closed- and open-canopy forest across the Northeast and Midwest...
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NASA Astrophysics Data System (ADS)
Bowden, David A.; Rowden, Ashley A.; Leduc, Daniel; Beaumont, Jennifer; Clark, Malcolm R.
2016-01-01
Growing economic interest in seabed resources in the deep-sea highlights the need for information about the spatial distribution and vulnerability to disturbance of benthic habitats and fauna. Categorisation of seabed habitats for management is often based on topographic features such as canyons and seamounts that can be distinguished using regional bathymetry ('mega-habitats'). This is practical but because such habitats are contiguous with others, there is potential for overlap in the communities associated with them. Because concepts of habitat and community vulnerability are based on the traits of individual taxa, the nature and extent of differences between communities have implications for strategies to manage the environmental effects of resource use. Using towed video camera transects, we surveyed mega-epifaunal communities of three topographically-defined habitats (canyon, seamount or knoll, and continental slope) and two physico-chemically defined meso-scale habitats (cold seep and hydrothermal vent) in two regions off New Zealand to assess whether each supports a distinct type of community. Cold seep and hydrothermal vent communities were strongly distinct from those in other habitats. Across the other habitats, however, distinctions between communities were often weak and were not consistent between regions. Dissimilarities among communities across all habitats were stronger and the density of filter-feeding taxa was higher in the Bay of Plenty than on the Hikurangi Margin, whereas densities of predatory and scavenging taxa were higher on the Hikurangi Margin. Substratum diversity at small spatial scales (<1 km) and trawl history were significantly correlated with community composition in both regions. We conclude that, (1) a lack of consistent distinction between communities raises questions about the general utility of topographically-defined mega-habitats in environmental management, (2) fine-scale survey of individual features is necessary to
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Habitat Demonstration Unit (HDU) Vertical Cylinder Habitat
NASA Technical Reports Server (NTRS)
Howe, Alan; Kennedy, Kriss J.; Gill, Tracy R.; Tri, Terry O.; Toups, Larry; Howard, Robert I.; Spexarth, Gary R.; Cavanaugh, Stephen; Langford, William M.; Dorsey, John T.
2014-01-01
NASA's Constellation Architecture Team defined an outpost scenario optimized for intensive mobility that uses small, highly mobile pressurized rovers supported by portable habitat modules that can be carried between locations of interest on the lunar surface. A compact vertical cylinder characterizes the habitat concept, where the large diameter maximizes usable flat floor area optimized for a gravity environment and allows for efficient internal layout. The module was sized to fit into payload fairings for the Constellation Ares V launch vehicle, and optimized for surface transport carried by the All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) mobility system. Launch and other loads are carried through the barrel to a top and bottom truss that interfaces with a structural support unit (SSU). The SSU contains self-leveling feet and docking interfaces for Tri-ATHLETE grasping and heavy lift. A pressurized module needed to be created that was appropriate for the lunar environment, could be easily relocated to new locations, and could be docked together in multiples for expanding pressurized volume in a lunar outpost. It was determined that horizontally oriented pressure vessels did not optimize floor area, which takes advantage of the gravity vector for full use. Hybrid hard-inflatable habitats added an unproven degree of complexity that may eventually be worked out. Other versions of vertically oriented pressure vessels were either too big, bulky, or did not optimize floor area. The purpose of the HDU vertical habitat module is to provide pressurized units that can be docked together in a modular way for lunar outpost pressurized volume expansion, and allow for other vehicles, rovers, and modules to be attached to the outpost to allow for IVA (intra-vehicular activity) transfer between them. The module is a vertically oriented cylinder with a large radius to allow for maximal floor area and use of volume. The modular, 5- m-diameter HDU vertical habitat
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Balzan, Mario V.
2012-01-01
Relatively little information is available on environmental associations and the conservation of Odonata in the Maltese Islands. Aquatic habitats are normally spatio-temporally restricted, often located within predominantly rural landscapes, and are thereby susceptible to farmland water management practices, which may create additional pressure on water resources. This study investigates how odonate assemblage structure and diversity are associated with habitat variables of local breeding habitats and the surrounding agricultural landscapes. Standardized survey methodology for adult Odonata involved periodical counts over selected water-bodies (valley systems, semi-natural ponds, constructed agricultural reservoirs). Habitat variables relating to the type of water body, the floristic and physiognomic characteristics of vegetation, and the composition of the surrounding landscape, were studied and analyzed through a multivariate approach. Overall, odonate diversity was associated with a range of factors across multiple spatial scales, and was found to vary with time. Lentic water-bodies are probably of high conservation value, given that larval stages were mainly associated with this habitat category, and that all species were recorded in the adult stage in this habitat type. Comparatively, lentic and lotic seminatural waterbodies were more diverse than agricultural reservoirs and brackish habitats. Overall, different odonate groups were associated with different vegetation life-forms and height categories. The presence of the great reed, Arundo donax L., an invasive alien species that forms dense stands along several water-bodies within the Islands, seems to influence the abundance and/or occurrence of a number of species. At the landscape scale, roads and other ecologically disturbed ground, surface water-bodies, and landscape diversity were associated with particular components of the odonate assemblages. Findings from this study have several implications for the
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Balzan, Mario V
2012-01-01
Relatively little information is available on environmental associations and the conservation of Odonata in the Maltese Islands. Aquatic habitats are normally spatio-temporally restricted, often located within predominantly rural landscapes, and are thereby susceptible to farmland water management practices, which may create additional pressure on water resources. This study investigates how odonate assemblage structure and diversity are associated with habitat variables of local breeding habitats and the surrounding agricultural landscapes. Standardized survey methodology for adult Odonata involved periodical counts over selected water-bodies (valley systems, semi-natural ponds, constructed agricultural reservoirs). Habitat variables relating to the type of water body, the floristic and physiognomic characteristics of vegetation, and the composition of the surrounding landscape, were studied and analyzed through a multivariate approach. Overall, odonate diversity was associated with a range of factors across multiple spatial scales, and was found to vary with time. Lentic water-bodies are probably of high conservation value, given that larval stages were mainly associated with this habitat category, and that all species were recorded in the adult stage in this habitat type. Comparatively, lentic and lotic seminatural waterbodies were more diverse than agricultural reservoirs and brackish habitats. Overall, different odonate groups were associated with different vegetation life-forms and height categories. The presence of the great reed, Arundo donax L., an invasive alien species that forms dense stands along several water-bodies within the Islands, seems to influence the abundance and/or occurrence of a number of species. At the landscape scale, roads and other ecologically disturbed ground, surface water-bodies, and landscape diversity were associated with particular components of the odonate assemblages. Findings from this study have several implications for the
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Bryson, Mitch; Ferrari, Renata; Figueira, Will; Pizarro, Oscar; Madin, Josh; Williams, Stefan; Byrne, Maria
2017-08-01
Habitat structural complexity is one of the most important factors in determining the makeup of biological communities. Recent advances in structure-from-motion and photogrammetry have resulted in a proliferation of 3D digital representations of habitats from which structural complexity can be measured. Little attention has been paid to quantifying the measurement errors associated with these techniques, including the variability of results under different surveying and environmental conditions. Such errors have the potential to confound studies that compare habitat complexity over space and time. This study evaluated the accuracy, precision, and bias in measurements of marine habitat structural complexity derived from structure-from-motion and photogrammetric measurements using repeated surveys of artificial reefs (with known structure) as well as natural coral reefs. We quantified measurement errors as a function of survey image coverage, actual surface rugosity, and the morphological community composition of the habitat-forming organisms (reef corals). Our results indicated that measurements could be biased by up to 7.5% of the total observed ranges of structural complexity based on the environmental conditions present during any particular survey. Positive relationships were found between measurement errors and actual complexity, and the strength of these relationships was increased when coral morphology and abundance were also used as predictors. The numerous advantages of structure-from-motion and photogrammetry techniques for quantifying and investigating marine habitats will mean that they are likely to replace traditional measurement techniques (e.g., chain-and-tape). To this end, our results have important implications for data collection and the interpretation of measurements when examining changes in habitat complexity using structure-from-motion and photogrammetry.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
McCall, James D; Macknick, Jordan E; Walston, Leroy J.
Of the many roles insects serve for ecosystem function, pollination is possibly the most important service directly linked to human well-being. However, land use changes have contributed to the decline of pollinators and their habitats. In agricultural landscapes that also support renewable energy developments such as utility-scale solar energy [USSE] facilities, opportunities may exist to conserve insect pollinators and locally restore their ecosystem services through the implementation of vegetation management approaches that aim to provide and maintain pollinator habitat at USSE facilities. As a first step toward understanding the potential agricultural benefits of solar-pollinator habitat, we identified areas of overlapmore » between USSE facilities and surrounding pollinator-dependent crop types in the United States (U.S.). Using spatial data on solar energy developments and crop types across the U.S., and assuming a pollinator foraging distance of 1.5 km, we identified over 3,500 km2 of agricultural land near existing and planned USSE facilities that may benefit from increased pollination services through the creation of pollinator habitat at the USSE facilities. The following five pollinator-dependent crop types accounted for over 90% of the agriculture near USSE facilities, and these could benefit most from the creation of pollinator habitat at existing and planned USSE facilities: soybeans, alfalfa, cotton, almonds, and citrus. We discuss how our results may be used to understand potential agro-economic implications of solar-pollinator habitat. Our results show that ecosystem service restoration through the creation of pollinator habitat could improve the sustainability of large-scale renewable energy developments in agricultural landscapes.« less
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Linking snake habitat use to nest predation risk in grassland birds: the dangers of shrub cover.
Klug, Page E; Jackrel, Sara L; With, Kimberly A
2010-03-01
Extremes in rangeland management, varying from too-frequent fire and intensive grazing to the suppression of both, threaten rangeland ecosystems worldwide. Intensive fire and grazing denude and homogenize vegetation whereas their suppression increases woody cover. Although habitat loss is implicated in grassland bird declines, degradation through intensive management or neglect also decreases breeding habitat and may reduce nesting success through increased rates of nest predation. Snakes are important nest predators, but little is known about how habitat use in snakes relates to predation risk for grassland birds nesting within tallgrass prairie subjected to different grazing and fire frequencies. We evaluated nest survival in the context of habitat used by nesting songbirds and two bird-eating snakes, the eastern yellowbelly racer Coluber constrictor flaviventris and Great Plains ratsnake Pantherophis emoryi. Daily nest survival rates decreased with increasing shrub cover and decreasing vegetation height, which characterize grasslands that have been neglected or intensively managed, respectively. Discriminant function analysis revealed that snake habitats were characterized by higher shrub cover, whereas successful nests were more likely to occur in areas with tall grass and forbs but reduced shrub cover. Because snakes often use shrub habitat, birds nesting in areas with increased shrub cover may be at higher risk of nest predation by snakes in addition to other predators known to use shrub habitat (e.g., mid-sized carnivores and avian predators). Depredated nests also occurred outside the discriminant space of the snakes, indicating that other predators (e.g., ground squirrels Spermophilus spp. and bullsnakes Pituophis catenifer) may be important in areas with denuded cover. Targeted removal of shrubs may increase nest success by minimizing the activity of nest predators attracted to shrub cover.
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Ten Brink, Dirk-Jan; Hendriksma, Harmen Pieter; Bruun, Hans Henrik
2013-02-01
This study examined the adaptive association between seed germination ecology and specialization to either forest or open habitats across a range of evolutionary lineages of seed plants, in order to test the hypotheses that (1) species' specialization to open vs. shaded habitats is consistently accompanied by specialization in their regeneration niche; and (2) species are thereby adapted to utilize different windows of opportunity in time (season) and space (habitat). Seed germination response to temperature, light and stratification was tested for 17 congeneric pairs, each consisting of one forest species and one open-habitat species. A factorial design was used with temperature levels and diurnal temperature variation (10 °C constant, 15-5 °C fluctuating, 20 °C constant, 25-15 °C fluctuating), and two light levels (light and darkness) and a cold stratification treatment. The congeneric species pair design took phylogenetic dependence into account. Species from open habitats germinated better at high temperatures, whereas forest species performed equally well at low and high temperatures. Forest species tended to germinate only after a period of cold stratification that could break dormancy, while species from open habitats generally germinated without cold stratification. The empirically derived germination strategies correspond quite well with establishment opportunities for forest and open-habitat plant species in nature. Annual changes in temperature and light regime in temperate forest delimit windows of opportunity for germination and establishment. Germination strategies of forest plants are adaptations to utilize such narrow windows in time. Conversely, lack of fit between germination ecology and environment may explain why species of open habitats generally fail to establish in forests. Germination strategy should be considered an important mechanism for habitat specialization in temperate herbs to forest habitats. The findings strongly suggest that
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MEGAEPIFAUNA-HABITAT RELATIONSHIPS IN YAQUINA BAY, OR
Habitat-based ecological risk assessments rely, in part, on estimates of the ecological value of the habitats at risk. As part of a larger programmatic effort to estimate estuarine habitat values, we determined megaepifauna-habitat relationships for four major intertidal habitat...
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Impact of experimental habitat manipulation on northern bobwhite survival
Peters, David C.; Brooke, Jarred M.; Tanner, Evan P.; Unger, Ashley M.; Keyser, Patrick D.; Harper, Craig A.; Clark, Joseph D.; Morgan, John J.
2015-01-01
= 0.025] vs. 0.355 [SE = 0.035]) on treatment than control units. Among habitat covariates, litter depth (β = −0.387, 95%CI = −0.5809 to −0.1930) was the most influential effect (negative) on survival. Additional experiments across a wider range of habitat conditions may be required to determine management intensity or duration thresholds required to elicit greater changes in survival for northern bobwhite populations.
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Headwater Stream Management Dichotomies: Local Amphibian Habitat vs. Downstream Fish Habitat
NASA Astrophysics Data System (ADS)
Jackson, C. R.
2002-12-01
Small headwater streams in mountainous areas of the Pacific Northwest often do not harbor fish populations because of low water depth and high gradients. Rather, these streams provide habitat for dense assemblages of stream-dwelling amphibians. A variety of management goals have been suggested for such streams such as encouraging large woody debris recruitment to assist in sediment trapping and valley floor formation, encouraging large woody debris recruitment to provide downstream wood when debris flows occur, providing continuous linear stream buffers within forest harvest areas to provide shade and bank stability, etc. A basic problem with analying the geomorphic or biotic benefits of any of these strategies is the lack of explicit management goals for such streams. Should managers strive to optimize downstream fish habitat, local amphibian habitat, or both? Through observational data and theoretical considerations, it will be shown that these biotic goals will lead to very different geomorphic management recommendations. For instance, woody debris greater than 60 cm diameter may assist in valley floor development, but it is likely to create subsurface channel flow of unknown value to amphibians. Trapping and retention of fine sediments within headwater streams may improve downstream spawning gravels, but degrades stream-dwelling amphibian habitat. In response to the need for descriptive information on habitat and channel morphology specific to small, non-fish-bearing streams in the Pacific Northwest, morphologies and wood frequencies in forty-two first- and second-order forested streams less than four meters wide were surveyed. Frequencies and size distributions of woody debris were compared between small streams and larger fish-bearing streams as well as between second-growth and virgin timber streams. Statistical models were developed to explore dominant factors affecting channel morphology and habitat. Findings suggest geomorphological relationships
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NASA Astrophysics Data System (ADS)
Heumann, B. W.; Guichard, F.; Seaquist, J. W.
2005-05-01
The HABSEED model uses remote sensing derived NPP as a surrogate for habitat quality as the driving mechanism for population growth and local seed dispersal. The model has been applied to the Sahel region of Africa. Results show that the functional response of plants to habitat quality alters population distribution. Plants more tolerant of medium quality habitat have greater distributions to the North while plants requiring only the best habitat are limited to the South. For all functional response types, increased seed production results in diminishing returns. Functional response types have been related to life history tradeoffs and r-K strategies based on the results. Results are compared to remote sensing derived vegetation land cover.
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Ma, Fei; Zhao, Changming; Milne, Richard; Ji, Mingfei; Chen, Litong; Liu, Jianquan
2010-01-01
The homoploid hybrid species Pinus densata is restricted to alpine habitats that exceed the altitude range of its two parental species, Pinus tabulaeformis and Pinus yunnanensis. Alpine habitats usually generate cold-induced water stress in plants. To understand the ecological differentiation between these three species, we examined their physiological responses to drought stress. Potted seedlings of three species were subjected to low, mild, moderate and severe water stress in an automatic-controlled glasshouse. Fifteen indicators of fitness were measured for each species in each treatment, and most of these decreased as drought increased. Pinus densata exhibited higher fitness than both parental species in terms of total dry mass production (TDM) and long-term water use efficiency (WUE(L)) across all treatments; several other ecophysiological traits were also extreme but not across every treatment, and not always in the highest stress treatment. These results indicate that extreme characters that have become well fixed in P. densata, confer a faster seedling growth rate and more efficient water use, which in turn should confer increased drought tolerance. These traits of P. densata likely promoted its ecological separation from its parental species and facilitated its successful colonization and establishment in high-altitude habitats.
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50 CFR 424.12 - Criteria for designating critical habitat.
Code of Federal Regulations, 2012 CFR
2012-10-01
... sufficiently well known to permit identification of an area as critical habitat. (b) In determining what areas... essential to the conservation of a given species and that may require special management considerations or... elements within the defined area that are essential to the conservation of the species. Known primary...
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The Importance of Biologically Relevant Microclimates in Habitat Suitability Assessments
Varner, Johanna; Dearing, M. Denise
2014-01-01
Predicting habitat suitability under climate change is vital to conserving biodiversity. However, current species distribution models rely on coarse scale climate data, whereas fine scale microclimate data may be necessary to assess habitat suitability and generate predictive models. Here, we evaluate disparities between temperature data at the coarse scale from weather stations versus fine-scale data measured in microhabitats required for a climate-sensitive mammal, the American pika (Ochotona princeps). We collected two years of temperature data in occupied talus habitats predicted to be suitable (high elevation) and unsuitable (low elevation) by the bioclimatic envelope approach. At low elevations, talus surface and interstitial microclimates drastically differed from ambient temperatures measured on-site and at a nearby weather station. Interstitial talus temperatures were frequently decoupled from high ambient temperatures, resulting in instantaneous disparities of over 30°C between these two measurements. Microhabitat temperatures were also highly heterogeneous, such that temperature measurements within the same patch of talus were not more correlated than measurements at distant patches. An experimental manipulation revealed that vegetation cover may cool the talus surface by up to 10°C during the summer, which may contribute to this spatial heterogeneity. Finally, low elevation microclimates were milder and less variable than typical alpine habitat, suggesting that, counter to species distribution model predictions, these seemingly unsuitable habitats may actually be better refugia for this species under climate change. These results highlight the importance of fine-scale microhabitat data in habitat assessments and underscore the notion that some critical refugia may be counterintuitive. PMID:25115894
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The importance of biologically relevant microclimates in habitat suitability assessments.
Varner, Johanna; Dearing, M Denise
2014-01-01
Predicting habitat suitability under climate change is vital to conserving biodiversity. However, current species distribution models rely on coarse scale climate data, whereas fine scale microclimate data may be necessary to assess habitat suitability and generate predictive models. Here, we evaluate disparities between temperature data at the coarse scale from weather stations versus fine-scale data measured in microhabitats required for a climate-sensitive mammal, the American pika (Ochotona princeps). We collected two years of temperature data in occupied talus habitats predicted to be suitable (high elevation) and unsuitable (low elevation) by the bioclimatic envelope approach. At low elevations, talus surface and interstitial microclimates drastically differed from ambient temperatures measured on-site and at a nearby weather station. Interstitial talus temperatures were frequently decoupled from high ambient temperatures, resulting in instantaneous disparities of over 30 °C between these two measurements. Microhabitat temperatures were also highly heterogeneous, such that temperature measurements within the same patch of talus were not more correlated than measurements at distant patches. An experimental manipulation revealed that vegetation cover may cool the talus surface by up to 10 °C during the summer, which may contribute to this spatial heterogeneity. Finally, low elevation microclimates were milder and less variable than typical alpine habitat, suggesting that, counter to species distribution model predictions, these seemingly unsuitable habitats may actually be better refugia for this species under climate change. These results highlight the importance of fine-scale microhabitat data in habitat assessments and underscore the notion that some critical refugia may be counterintuitive.
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Partial gravity habitat study: With application to lunar base design
NASA Technical Reports Server (NTRS)
Capps, Stephen; Lorandos, Jason; Akhidime, Eval; Bunch, Michael; Lund, Denise; Moore, Nathan; Murakawa, Kio; Bell, Larry; Trotti, Guillermo; Neubek, Deb
1989-01-01
Comprehensive design requirements associated with designing habitats for humans in a partial gravity environment were investigated and then applied to a lunar base design. Other potential sites for application include planetary surfaces such as Mars, variable gravity research facilities, or a rotating spacecraft. Design requirements for partial gravity environments include: (1) locomotion changes in less than normal Earth gravity; (2) facility design issues, such as interior configuration, module diameter and geometry; and (3) volumetric requirements based on the previous as well as psychological issues involved in prolonged isolation. For application to a Lunar Base, it was necessary to study the exterior architecture and configuration to insure optimum circulation patterns while providing dual egress. Radiation protection issues were addressed to provide a safe and healthy environment for the crew, and finally, the overall site was studied to locate all associated facilities in context with the habitat. Mission planning was not the purpose of this study; therefore, a Lockheed scenario was used as an outline for the Lunar Base application, which was then modified to meet the project needs.
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Gürtler, Ricardo E.; Cecere, María C.; Fernández, María del Pilar; Vazquez-Prokopec, Gonzalo M.; Ceballos, Leonardo A.; Gurevitz, Juan M.; Kitron, Uriel; Cohen, Joel E.
2014-01-01
Background Triatoma infestans —the principal vector of the infection that causes Chagas disease— defies elimination efforts in the Gran Chaco region. This study identifies the types of human-made or -used structures that are key sources of these bugs in the initial stages of house reinfestation after an insecticide spraying campaign. Methodology and Principal Findings We measured demographic and blood-feeding parameters at two geographic scales in 11 rural communities in Figueroa, northwest Argentina. Of 1,297 sites searched in spring, 279 (21.5%) were infested. Bug abundance per site and female fecundity differed significantly among habitat types (ecotopes) and were highly aggregated. Domiciles (human sleeping quarters) had maximum infestation prevalence (38.7%), human-feeding bugs and total egg production, with submaximal values for other demographic and blood-feeding attributes. Taken collectively peridomestic sites were three times more often infested than domiciles. Chicken coops had greater bug abundance, blood-feeding rates, engorgement status, and female fecundity than pig and goat corrals. The host-feeding patterns were spatially structured yet there was strong evidence of active dispersal of late-stage bugs between ecotopes. Two flight indices predicted that female fliers were more likely to originate from kitchens and domiciles, rejecting our initial hypothesis that goat and pig corrals would dominate. Conclusions and Significance Chicken coops and domiciles were key source habitats fueling rapid house reinfestation. Focusing control efforts on ecotopes with human-fed bugs (domiciles, storerooms, goat corrals) would neither eliminate the substantial contributions to bug population growth from kitchens, chicken coops, and pig corrals nor stop dispersal of adult female bugs from kitchens. Rather, comprehensive control of the linked network of ecotopes is required to prevent feeding on humans, bug population growth, and bug dispersal simultaneously. Our
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Steven M. Speich; Terrence R. Wahl
1995-01-01
Marbled Murrelets occur in Puget Sound marine habitats in relatively low numbers. The rates of occurrence of murrelets on censuses within marine habitats is generally low. Further analysis is required to determine if low occurrence rates are a general function of the movement of birds, or their consistent occurrence on particular censuses and not on others. Qualitative...
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Hodgson, Jenny A; Moilanen, Atte; Thomas, Chris D
2009-06-01
Many species have to track changes in the spatial distribution of suitable habitat from generation to generation. Understanding the dynamics of such species will likely require spatially explicit models, and patch-based metapopulation models are potentially appropriate. However, relatively little attention has been paid to developing metapopulation models that include habitat dynamics, and very little to testing the predictions of these models. We tested three predictions from theory about the differences between dynamic habitat metapopulations and their static counterparts using long-term survey data from two metapopulations of the butterfly Plebejus argus. As predicted, we showed first that the metapopulation inhabiting dynamic habitat had a lower level of habitat occupancy, which could not be accounted for by other differences between the metapopulations. Secondly, we found that patch occupancy did not significantly increase with increasing patch connectivity in dynamic habitat, whereas there was a strong positive connectivity-occupancy relationship in static habitat. Thirdly, we found no significant relationship between patch occupancy and patch quality in dynamic habitat, whereas there was a strong, positive quality-occupancy relationship in static habitat. Modeling confirmed that the differences in mean patch occupancy and connectivity-occupancy slope could arise without changing the species' metapopulation parameters-importantly, without changing the dependence of colonization upon connectivity. We found that, for a range of landscape scenarios, successional simulations always produced a lower connectivity-occupancy slope than comparable simulations with static patches, whether compared like-for-like or controlling for mean occupancy. We conclude that landscape-scale studies may often underestimate the importance of connectivity for species occurrence and persistence because habitat turnover can obscure the connectivity-occupancy relationship in commonly
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Fountain, Emily D; Kang, Jung Koo; Tempel, Douglas J; Palsbøll, Per J; Pauli, Jonathan N; Zachariah Peery, M
2018-01-01
Understanding how habitat quality in heterogeneous landscapes governs the distribution and fitness of individuals is a fundamental aspect of ecology. While mean individual fitness is generally considered a key to assessing habitat quality, a comprehensive understanding of habitat quality in heterogeneous landscapes requires estimates of dispersal rates among habitat types. The increasing accessibility of genomic approaches, combined with field-based demographic methods, provides novel opportunities for incorporating dispersal estimation into assessments of habitat quality. In this study, we integrated genomic kinship approaches with field-based estimates of fitness components and approximate Bayesian computation (ABC) procedures to estimate habitat-specific dispersal rates and characterize habitat quality in two-toed sloths (Choloepus hoffmanni) occurring in a Costa Rican agricultural ecosystem. Field-based observations indicated that birth and survival rates were similar in a sparsely shaded cacao farm and adjacent cattle pasture-forest mosaic. Sloth density was threefold higher in pasture compared with cacao, whereas home range size and overlap were greater in cacao compared with pasture. Dispersal rates were similar between the two habitats, as estimated using ABC procedures applied to the spatial distribution of pairs of related individuals identified using 3,431 single nucleotide polymorphism and 11 microsatellite locus genotypes. Our results indicate that crops produced under a sparse overstorey can, in some cases, constitute lower-quality habitat than pasture-forest mosaics for sloths, perhaps because of differences in food resources or predator communities. Finally, our study demonstrates that integrating field-based demographic approaches with genomic methods can provide a powerful means for characterizing habitat quality for animal populations occurring in heterogeneous landscapes. © 2017 John Wiley & Sons Ltd.
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Randall J. Wilk; Martin G. Raphael; Thomas D. Bloxton
2016-01-01
Marbled Murrelets (Brachyramphus marmoratus) are listed as threatened in the portion of their range extending from British Columbia to California due to loss of nesting habitat. Recovery of Marbled Murrelet populations requires a better understanding of the characteristics of their nesting habitat in this part of their range. Our objective,...
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Harper, Elizabeth B; Rittenhouse, Tracy A G; Semlitsch, Raymond D
2008-10-01
Much of the biodiversity associated with isolated wetlands requires aquatic and terrestrial habitat to maintain viable populations. Current federal wetland regulations in the United States do not protect isolated wetlands or extend protection to surrounding terrestrial habitat. Consequently, some land managers, city planners, and policy makers at the state and local levels are making an effort to protect these wetland and neighboring upland habitats. Balancing human land-use and habitat conservation is challenging, and well-informed land-use policy is hindered by a lack of knowledge of the specific risks of varying amounts of habitat loss. Using projections of wood frog (Rana sylvatica) and spotted salamander (Ambystoma maculatum) populations, we related the amount of high-quality terrestrial habitat surrounding isolated wetlands to the decline and risk of extinction of local amphibian populations. These simulations showed that current state-level wetland regulations protecting 30 m or less of surrounding terrestrial habitat are inadequate to support viable populations of pool-breeding amphibians. We also found that species with different life-history strategies responded differently to the loss and degradation of terrestrial habitat. The wood frog, with a short life span and high fecundity, was most sensitive to habitat loss and isolation, whereas the longer-lived spotted salamander with lower fecundity was most sensitive to habitat degradation that lowered adult survival rates. Our model results demonstrate that a high probability of local amphibian population persistence requires sufficient terrestrial habitat, the maintenance of habitat quality, and connectivity among local populations. Our results emphasize the essential role of adequate terrestrial habitat to the maintenance of wetland biodiversity and ecosystem function and offer a means of quantifying the risks associated with terrestrial habitat loss and degradation.
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New England wildlife: management forested habitats
Richard M. DeGraaf; Mariko Yamasaki; William B. Leak; John W. Lanier
1992-01-01
Presents silvicultural treatments for six major cover-type groups in New England to produce stand conditions that provide habitat opportunities for a wide range of wildlife species. Includes matrices for species occurrence and utilization by forested and nonforested habitats, habitat breadth and size class, and structural habitat features for the 338 wildlife species...
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Moore, Kara A.; Stanton, Maureen L.
2014-01-01
Adaptation to novel conditions beyond current range boundaries requires the presence of suitable sites within dispersal range, but may be impeded when emigrants encounter poor habitat and sharply different selection pressures. We investigated fine-scale spatial heterogeneity in ecological dynamics and selection at a local population boundary of the annual plant Gilia tricolor. In two years, we planted G. tricolor seeds in core habitat, margin habitat at the edge of the local range, and exterior habitat in order to measure spatial and temporal variation in habitat quality, opportunity for selection, and selection on phenotypic traits. We found a striking decline in average habitat quality with distance from the population core, yet some migrant seeds were successful in suitable, unoccupied microsites at and beyond the range boundary. Total and direct selection on four out of five measured phenotypic traits varied across habitat zones, as well as between years. Moreover, the margin habitat often exerted unique selection pressures that were not intermediate between core and exterior habitats. This study reveals that a combination of ecological and evolutionary forces, including propagule limitation, variation in habitat quality and spatial heterogeneity in phenotypic selection may reduce opportunities for adaptive range expansion, even across a very local population boundary. PMID:24717472
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Ampou, Eghbert Elvan; Ouillon, Sylvain; Andréfouët, Serge
2018-06-01
The Coral Triangle is the epicenter of marine biodiversity, yet the numbers of habitats that can be found on coral reefs remain poorly described. First surveys for habitat mapping in Indonesia revealed a high number of habitats (>150) even for structurally simple reefs. To be able to represent all these habitats, typical habitat mapping procedures and performances are poorly effective even using very high resolution satellite images. Using Bunaken Island (North Sulawesi, Indonesia) as a case study, we devised a way to maintain all the in situ habitat information in remote sensing habitat map products without loss and with mapping procedures based on photo-interpretation. The result is a product which is consistent with a per-polygon fuzzy classification. As such, it is a complex product that meets our habitat representation goal, but its complexity can also limit its immediate use by managers and conservation planners when analyses per habitat are needed. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Wildlife habitat considerations
Helen Y. Smith
2000-01-01
Fire, insects, disease, harvesting, and precommercial thinning all create mosaics on Northern Rocky Mountain landscapes. These mosaics are important for faunal habitat. Consequently, changes such as created openings or an increase in heavily stocked areas affect the water, cover, and food of forest habitats. The âno actionâ alternative in ecosystem management of low...
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Matchett, Elliott L.; Fleskes, Joseph
2018-01-01
California's Central Valley provides critical, but threatened habitat and food resources for migrating and wintering waterfowl, shorebirds, and other waterbirds. The Central Valley is comprised of nine basins that were defined by the Central Valley Joint Venture (CVJV) to assist in conservation planning. Basins vary in composition and extent of habitats, which primarily include croplands and wetlands that rely on water supplies shared with other competing human and environmental uses. Changes in climate, urban development, and water supply management are uncertain and could reduce future availability of water supplies supporting waterbird habitats and limit effectiveness of wetland restoration planned by the CVJV to support wintering waterbirds. We modeled 17 plausible scenarios including combinations of three climate projections, three urbanization rates, and five water supply management options to promote agricultural and urban water uses, with and without wetland restoration. Our research examines the reduction in quantity and quality of habitats during the fall migration-wintering period by basin under each scenario, and the efficacy of planned wetland restoration to compensate reductions in flooded areas of wetland habitats. Scenario combinations of projected climate, urbanization, and water supply management options reduced availability of flooded cropland and wetland habitats during fall-winter and degraded the quality of seasonal wetlands (i.e., summer-irrigation for improved forage production), though the extent and frequency of impacts varied by basin. Planned wetland restoration may substantially compensate for scenario-related effects on wetland habitats in each basin. However, results indicate that Colusa, Butte, Sutter, San Joaquin, and Tulare Basins may require additional conservation to support summer-irrigation of seasonal wetlands and winter-flooding of cropland habitats. Still further conservation may be required to provide sufficient areas of
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Island ecosystems maintain greater endemic biodiversity such that changes in land cover can have dramatic impacts on wildlife populations that depend on unique and limited habitat. Sustainable land use decisions that minimize habitat loss require multi-faceted evaluation of cost...
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1. A principal challenge of species conservation is to identify the specific habitats that are essential for long-term persistence or recovery of species at risk. However, many commonly used approaches to identifying important habitats do not provide direct insight into the contr...
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Gerrity, Paul C.; Guy, C.S.; Gardner, W.M.
2008-01-01
Natural recruitment of pallid sturgeon Scaphirhynchus albus has not been observed in the Missouri River above Fort Peck Reservoir, Montana, for at least 20 years. To augment the population, age-1 hatchery-reared juvenile pallid sturgeon were released in 1998. The objective of this study was to evaluate the habitat use of these fish and compare it with that of indigenous shovelnose sturgeon S. platorynchus. Twenty-nine juvenile pallid sturgeon and 21 indigenous shovelnose sturgeon were implanted with radio transmitters in 2003 and 2004. The two species showed no differences in habitat use in terms of mean depth, cross-sectional relative depth, longitudinal relative depth, column velocity, bottom velocity, and channel width. However, there were seasonal differences within both species for cross-sectional relative depth, column velocity, and channel width. Both shovelnose sturgeon and juvenile pallid sturgeon were primarily associated with silt and sand substrate. However, shovelnose sturgeon were associated with gravel and cobble substrate more than juvenile pallid sturgeon. Shovelnose sturgeon and juvenile pallid sturgeon both selected reaches without islands and avoided reaches with islands; the two species also selected main-channel habitat and avoided secondary channels. Mean home range was similar between juvenile pallid sturgeon (15 km; 90% confidence interval, ??5.0 km) and shovelnose sturgeon (16.5 km; ??4.7 km). Spatial distribution differed between the two species, with shovelnose sturgeon using upstream areas more often than juvenile pallid sturgeon. Twenty-eight percent of juvenile pallid sturgeon frequented 60 km of lotie habitat that would be inundated by Fort Peck Reservoir at maximum pool. Stocking juvenile pallid sturgeon can successfully augment the wild pallid sturgeon population in the Missouri River above Fort Peck Reservoir, which is crucial to the long-term recovery of the species. However, water-level management in downstream reservoirs such
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Sound solutions for habitat monitoring
Mary M. Rowland; Lowell H. Suring; Christina D. Vojta
2015-01-01
For agencies and organizations to effectively manage wildlife, knowledge about the status and trend of wildlife habitat is critical. Traditional wildlife monitoring, however, has focused on populations rather than habitat, because ultimately population status drives long-term species viability. Still, habitat loss has contributed to the decline of nearly all at-risk...
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Winter habitat associations of diurnal raptors in Californias Central Valley
Pandolrno, E.R.; Herzog, M.P.; Hooper, S.L.; Smith, Z.
2011-01-01
The wintering raptors of California's Central Valley are abundant and diverse. Despite this, little information exists on the habitats used by these birds in winter. We recorded diurnal raptors along 19 roadside survey routes throughout the Central Valley for three consecutive winters between 2007 and 2010. We obtained data sufficient to determine significant positive and negative habitat associations for the White-tailed Kite (Elanus leucurus), Bald Eagle {Haliaeetus leucocephalus), Northern Harrier (Circus cyaneus), Red-tailed Hawk (Buteo jamaicensis), Ferruginous Hawk (Buteo regalis), Rough-legged Hawk (Buteo lagopus), American Kestrel (Falco sparverius), and Prairie Falcon (Falco mexicanus). The Prairie Falcon and Ferruginous and Rough-legged hawks showed expected strong positive associations with grasslands. The Bald Eagle and Northern Harrier were positively associated not only with wetlands but also with rice. The strongest positive association for the White-tailed Kite was with wetlands. The Red-tailed Hawk was positively associated with a variety of habitat types but most strongly with wetlands and rice. The American Kestrel, Northern Harrier, and White-tailed Kite were positively associated with alfalfa. Nearly all species were negatively associated with urbanized landscapes, orchards, and other intensive forms of agriculture. The White-tailed Kite, Northern Harrier, Redtailed Hawk, Ferruginous Hawk, and American Kestrel showed significant negative associations with oak savanna. Given the rapid conversion of the Central Valley to urban and intensive agricultural uses over the past few decades, these results have important implications for conservation of these wintering raptors in this region.
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Gorman, Owen T.; Yule, Daniel L.; Stockwell, Jason D.
2012-01-01
Diel migration patterns of fishes in nearshore (15–80 m depth) and offshore (>80 m) waters of Lake Superior were examined to assess the potential for diel migration to link benthic and pelagic, and nearshore and offshore habitats. In our companion article, we described three types of diel migration: diel vertical migration (DVM), diel bank migration (DBM), and no diel migration. DVM was expressed by fishes migrating from benthopelagic to pelagic positions and DBM was expressed by fishes migrating horizontally from deep to shallow waters at night. Fishes not exhibiting diel migration typically showed increased activity by moving from benthic to benthopelagic positions within demersal habitat. The distribution and biomass of fishes in Lake Superior was characterized by examining 704 bottom trawl samples collected between 2001 and 2008 from four depth zones: ≤40, 41–80, 81–160, and >160 m. Diel migration behaviors of fishes described in our companion article were applied to estimates of areal biomass (kg ha−1) for each species by depth zone. The relative strength of diel migrations were assessed by applying lake area to areal biomass estimates for each species by depth zone to yield estimates of lake-wide biomass (metric tonnes). Overall, species expressing DVM accounted for 83%, DBM 6%, and non-migration 11% of the total lake-wide community biomass. In nearshore waters, species expressing DVM represented 74% of the biomass, DBM 25%, and non-migration 1%. In offshore waters, species expressing DVM represented 85%, DBM 1%, and non-migration 14% of the biomass. Of species expressing DVM, 83% of total biomass occurred in offshore waters. Similarly, 97% of biomass of non-migrators occurred in offshore waters while 83% of biomass of species expressing DBM occurred in nearshore waters. A high correlation (R2 = 0.996) between lake area and community biomass by depth zone resulted in 81% of the lake-wide biomass occurring in offshore waters. Accentuating this
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Ocean acidification limits temperature-induced poleward expansion of coral habitats around Japan
NASA Astrophysics Data System (ADS)
Yara, Y.; Vogt, M.; Fujii, M.; Yamano, H.; Hauri, C.; Steinacher, M.; Gruber, N.; Yamanaka, Y.
2012-12-01
Using results from four coupled global carbon cycle-climate models combined with in situ observations, we estimate the effects of future global warming and ocean acidification on potential habitats for tropical/subtropical and temperate coral communities in the seas around Japan. The suitability of coral habitats is classified on the basis of the currently observed regional ranges for temperature and saturation states with regard to aragonite (Ωarag). We find that, under the "business as usual" SRES A2 scenario, coral habitats are projected to expand northward by several hundred kilometers by the end of this century. At the same time, coral habitats are projected to become sandwiched between regions where the frequency of coral bleaching will increase, and regions where Ωarag will become too low to support sufficiently high calcification rates. As a result, the habitat suitable for tropical/subtropical corals around Japan may be reduced by half by the 2020s to 2030s, and is projected to disappear by the 2030s to 2040s. The habitat suitable for the temperate coral communities is also projected to decrease, although at a less pronounced rate, due to the higher tolerance of temperate corals for low Ωarag. Our study has two important caveats: first, it does not consider the potential adaptation of the coral communities, which would permit them to colonize habitats that are outside their current range. Second, it also does not consider whether or not coral communities can migrate quickly enough to actually occupy newly emerging habitats. As such, our results serve as a baseline for the assessment of the future evolution of coral habitats, but the consideration of important biological and ecological factors and feedbacks will be required to make more accurate projections.
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Comparison of macroinvertebrate-derived stream quality metrics between snag and riffle habitats
Stepenuck, K.F.; Crunkilton, R.L.; Bozek, Michael A.; Wang, L.
2008-01-01
We compared benthic macroinvertebrate assemblage structure at snag and riffle habitats in 43 Wisconsin streams across a range of watershed urbanization using a variety of stream quality metrics. Discriminant analysis indicated that dominant taxa at riffles and snags differed; Hydropsychid caddisflies (Hydropsyche betteni and Cheumatopsyche spp.) and elmid beetles (Optioservus spp. and Stenemlis spp.) typified riffles, whereas isopods (Asellus intermedius) and amphipods (Hyalella azteca and Gammarus pseudolimnaeus) predominated in snags. Analysis of covariance indicated that samples from snag and riffle habitats differed significantly in their response to the urbanization gradient for the Hilsenhoff biotic index (BI), Shannon's diversity index, and percent of filterers, shredders, and pollution intolerant Ephemeroptera, Plecoptera, and Trichoptera (EPT) at each stream site (p ??? 0.10). These differences suggest that although macroinvertebrate assemblages present in either habitat type are sensitive to detecting the effects of urbanization, metrics derived from different habitats should not be intermixed when assessing stream quality through biomonitoring. This can be a limitation to resource managers who wish to compare water quality among streams where the same habitat type is not available at all stream locations, or where a specific habitat type (i.e., a riffle) is required to determine a metric value (i.e., BI). To account for differences in stream quality at sites lacking riffle habitat, snag-derived metric values can be adjusted based on those obtained from riffles that have been exposed to the same level of urbanization. Comparison of nonlinear regression equations that related stream quality metric values from the two habitat types to percent watershed urbanization indicated that snag habitats had on average 30.2 fewer percent EPT individuals, a lower diversity index value than riffles, and a BI value of 0.29 greater than riffles. ?? 2008 American Water
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Habitat Evaluation Procedures (HEP) Report : Oxbow Conservation Area, 2002-2005 Technical Report.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cochran, Brian
2005-02-01
This Habitat Evaluation Procedure (HEP) study was performed to determine baseline habitat units on the Oxbow Conservation Area in Grant County, Oregon. The evaluation is a required part of the Memorandum of Agreement between the Confederated Tribes of the Warm Springs and Bonneville Power Administration (BPA) relating to the acquisition and management of the Oxbow Conservation Area. The HEP team was comprised of individuals from the Washington Department of Fish and Wildlife and the Confederated Tribes of the Warm Springs Reservation of Oregon. The survey was conducted using the following HEP evaluation models for key species: black-capped chickadee (Poecile atricapilla),more » mallard (Anas platyrhynchos), mink (Mustela vison), western meadowlark (Sturnella neglecta), white-tailed deer (Odocoileus virginiana), and yellow warbler (Dendroica petechia). Cover types used in this survey were conifer forest, irrigated meadow, riparian meadow, upland meadow, riparian shrub, upland shrub, and mine tailings. The project generated 701.3 habitat units for mitigation crediting purposes. Results for each HEP species are: (1) Black-capped chickadee habitat was good, with only isolated areas lacking snags or having low tree canopy cover. (2) Mallard habitat was poor in upland meadows and marginal elsewhere due to a lack of herbaceous/shrub cover and low herbaceous height. (3) Mink habitat was good, limited only by the lack of the shrub component. (4) Western meadowlark habitat was marginal in upland meadow and mine tailing cover types and good in irrigated meadow. Percent cover of grass and height of herbaceous variables were limiting factors. (5) White-tailed deer habitat was marginal due to relatively low tree canopy cover, reduced shrub cover, and limited browse diversity. (6) Yellow Warbler habitat was marginal due to less than optimum shrub height and the lack of hydrophytic shrubs. General ratings (poor, marginal, etc.) are described in the introduction section.« less
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Resampling method for applying density-dependent habitat selection theory to wildlife surveys.
Tardy, Olivia; Massé, Ariane; Pelletier, Fanie; Fortin, Daniel
2015-01-01
Isodar theory can be used to evaluate fitness consequences of density-dependent habitat selection by animals. A typical habitat isodar is a regression curve plotting competitor densities in two adjacent habitats when individual fitness is equal. Despite the increasing use of habitat isodars, their application remains largely limited to areas composed of pairs of adjacent habitats that are defined a priori. We developed a resampling method that uses data from wildlife surveys to build isodars in heterogeneous landscapes without having to predefine habitat types. The method consists in randomly placing blocks over the survey area and dividing those blocks in two adjacent sub-blocks of the same size. Animal abundance is then estimated within the two sub-blocks. This process is done 100 times. Different functional forms of isodars can be investigated by relating animal abundance and differences in habitat features between sub-blocks. We applied this method to abundance data of raccoons and striped skunks, two of the main hosts of rabies virus in North America. Habitat selection by raccoons and striped skunks depended on both conspecific abundance and the difference in landscape composition and structure between sub-blocks. When conspecific abundance was low, raccoons and striped skunks favored areas with relatively high proportions of forests and anthropogenic features, respectively. Under high conspecific abundance, however, both species preferred areas with rather large corn-forest edge densities and corn field proportions. Based on random sampling techniques, we provide a robust method that is applicable to a broad range of species, including medium- to large-sized mammals with high mobility. The method is sufficiently flexible to incorporate multiple environmental covariates that can reflect key requirements of the focal species. We thus illustrate how isodar theory can be used with wildlife surveys to assess density-dependent habitat selection over large
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Renzi, Monia; Blašković, Andrea; Fastelli, Paolo; Marcelli, Massimiliano; Guerranti, Cristiana; Cannas, Susanna; Barone, Lorenzo; Massara, Francesca
2018-05-01
This study estimated for the first time the total loads of plastic litter (macro- meso- and micro-plastics) in sediments of different habitat types from the Northern Adriatic Sea. Samples were collected in March 2016. The sampling sites were settled in shoreline, on the C. nodosa bottoms, Amphioxus sands, and Mäerl bed habitats. Microplastics items were present in all sampling site and ranging within 137-703 items/kg d.w. from Mäerl bed habitat to the shoreline. In C. nodosa bottoms 170 items/kg d.w. were found, while in Amphioxus sands were recorded on average 194 items/kg d.w. Due to the absence of statistical associations among litter levels and abundance of B. lanceolatum in the study area, this research present the needs to develop a new method and more research to for the evaluation of how much the interrelation between sensible habitats and microplastic exist. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Hitchman, Sean M; Mather, Martha E; Smith, Joseph M; Fencl, Jane S
2018-01-01
Conserving native biodiversity in the face of human- and climate-related impacts is a challenging and globally important ecological problem that requires an understanding of spatially connected, organismal-habitat relationships. Globally, a suite of disturbances (e.g., agriculture, urbanization, climate change) degrades habitats and threatens biodiversity. A mosaic approach (in which connected, interacting collections of juxtaposed habitat patches are examined) provides a scientific foundation for addressing many disturbance-related, ecologically based conservation problems. For example, if specific habitat types disproportionately increase biodiversity, these keystones should be incorporated into research and management plans. Our sampling of fish biodiversity and aquatic habitat along ten 3-km sites within the Upper Neosho River subdrainage, KS, from June-August 2013 yielded three generalizable ecological insights. First, specific types of mesohabitat patches (i.e., pool, riffle, run, and glide) were physically distinct and created unique mosaics of mesohabitats that varied across sites. Second, species richness was higher in riffle mesohabitats when mesohabitat size reflected field availability. Furthermore, habitat mosaics that included more riffles had greater habitat diversity and more fish species. Thus, riffles (<5% of sampled area) acted as keystone habitats. Third, additional conceptual development, which we initiate here, can broaden the identification of keystone habitats across ecosystems and further operationalize this concept for research and conservation. Thus, adopting a mosaic approach can increase scientific understanding of organismal-habitat relationships, maintain natural biodiversity, advance spatial ecology, and facilitate effective conservation of native biodiversity in human-altered ecosystems. © 2017 John Wiley & Sons Ltd.
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Muposhi, Victor K.; Gandiwa, Edson; Chemura, Abel; Bartels, Paul; Makuza, Stanley M.; Madiri, Tinaapi H.
2016-01-01
An understanding of the habitat selection patterns by wild herbivores is critical for adaptive management, particularly towards ecosystem management and wildlife conservation in semi arid savanna ecosystems. We tested the following predictions: (i) surface water availability, habitat quality and human presence have a strong influence on the spatial distribution of wild herbivores in the dry season, (ii) habitat suitability for large herbivores would be higher compared to medium-sized herbivores in the dry season, and (iii) spatial extent of suitable habitats for wild herbivores will be different between years, i.e., 2006 and 2010, in Matetsi Safari Area, Zimbabwe. MaxEnt modeling was done to determine the habitat suitability of large herbivores and medium-sized herbivores. MaxEnt modeling of habitat suitability for large herbivores using the environmental variables was successful for the selected species in 2006 and 2010, except for elephant (Loxodonta africana) for the year 2010. Overall, large herbivores probability of occurrence was mostly influenced by distance from rivers. Distance from roads influenced much of the variability in the probability of occurrence of medium-sized herbivores. The overall predicted area for large and medium-sized herbivores was not different. Large herbivores may not necessarily utilize larger habitat patches over medium-sized herbivores due to the habitat homogenizing effect of water provisioning. Effect of surface water availability, proximity to riverine ecosystems and roads on habitat suitability of large and medium-sized herbivores in the dry season was highly variable thus could change from one year to another. We recommend adaptive management initiatives aimed at ensuring dynamic water supply in protected areas through temporal closure and or opening of water points to promote heterogeneity of wildlife habitats. PMID:27680673
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Maria Vergara; Samuel A. Cushman; Fermin Urra; Aritz Ruiz-Gonzalez
2016-01-01
Multispecies and multiscale habitat suitability models (HSM) are important to identify the environmental variables and scales influencing habitat selection and facilitate the comparison of closely related species with different ecological requirements. Objectives This study explores the multiscale relationships of habitat suitability for the pine (Martes...
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Hunter, Richard D.; Fisher, Robert N.; Crooks, Kevin R.
2003-01-01
Although the fragmentation of the natural landscape of coastal southern California, USA, is accelerating, large-scale assessments of regional connectivity are lacking. Because of their large area requirements and long dispersal movements, mammalian carnivores can be effective focal species to use when evaluating landscape-level connectivity. Our goal was to make an initial assessment of the extent of landscape-level connectivity in coastal southern California using mountain lions (Felis concolor [Linnaeus]) and bobcats (Felis rufus [Shreber]) as focal species. We first characterized habitat preferences for mountain lions and bobcats from previously derived habitat relationship models for these species; the resulting maps provided a coarse view of habitat preferences for use at regional scales. We then constructed GIS models to evaluate the disturbance impact of roadways and development, major determinants of carnivore distribution and abundance in the south coast region. Finally, we combined the habitat relationship models with the disturbance impact models to characterize habitat connectivity for mountain lions and bobcats in the ecoregion. Habitat connectivity in the ecoregion appeared higher for bobcats than for mountain lions due in part to higher habitat suitability for bobcats in coastal lowland areas. Our models suggest that much of the key carnivore habitat in the coastal southern California is at risk; over 80% of high suitability habitat and over 90% of medium suitability habitat for carnivores is found in the least protected land management classes. Overall, these models allow for (1) identification of core habitat blocks for carnivores and key landscape connections between core areas, (2) evaluation of the level of protection of these areas, and (3) a regional framework within which to develop and coordinate local management and conservation plans.
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A Candidate Vegetation Index of Biological Integrity Based on Species Dominance and Habitat Fidelity
Gara, Brian D; Stapanian, Martin A.
2015-01-01
Indices of biological integrity of wetlands based on vascular plants (VIBIs) have been developed in many areas of the USA and are used in some states to make critical management decisions. An underlying concept of all VIBIs is that they respond negatively to disturbance. The Ohio VIBI (OVIBI) is calculated from 10 metrics, which are different for each wetland vegetation class. We present a candidate vegetation index of biotic integrity based on floristic quality (VIBI-FQ) that requires only two metrics to calculate an overall score regardless of vegetation class. These metrics focus equally on the critical ecosystem elements of diversity and dominance as related to a species’ degree of fidelity to habitat requirements. The indices were highly correlated but varied among vegetation classes. Both indices responded negatively with a published index of wetland disturbance in 261 Ohio wetlands. Unlike VIBI-FQ, however, errors in classifying wetland vegetation may lead to errors in calculating OVIBI scores. This is especially critical when assessing the ecological condition of rapidly developing ecosystems typically associated with wetland restoration and creation projects. Compared to OVIBI, the VIBI-FQ requires less field work, is much simpler to calculate and interpret, and can potentially be applied to all habitat types. This candidate index, which has been “standardized” across habitats, would make it easier to prioritize funding because it would score the “best” and “worst” of all habitats appropriately and allow for objective comparison across different vegetation classes.
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Effects of differential habitat warming on complex communities.
Tunney, Tyler D; McCann, Kevin S; Lester, Nigel P; Shuter, Brian J
2014-06-03
Food webs unfold across a mosaic of micro and macro habitats, with each habitat coupled by mobile consumers that behave in response to local environmental conditions. Despite this fundamental characteristic of nature, research on how climate change will affect whole ecosystems has overlooked (i) that climate warming will generally affect habitats differently and (ii) that mobile consumers may respond to this differential change in a manner that may fundamentally alter the energy pathways that sustain ecosystems. This reasoning suggests a powerful, but largely unexplored, avenue for studying the impacts of climate change on ecosystem functioning. Here, we use lake ecosystems to show that predictable behavioral adjustments to local temperature differentials govern a fundamental structural shift across 54 food webs. Data show that the trophic pathways from basal resources to a cold-adapted predator shift toward greater reliance on a cold-water refuge habitat, and food chain length increases, as air temperatures rise. Notably, cold-adapted predator behavior may substantially drive this decoupling effect across the climatic range in our study independent of warmer-adapted species responses (for example, changes in near-shore species abundance and predator absence). Such modifications reflect a flexible food web architecture that requires more attention from climate change research. The trophic pathway restructuring documented here is expected to alter biomass accumulation, through the regulation of energy fluxes to predators, and thus potentially threatens ecosystem sustainability in times of rapid environmental change.
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18 CFR 1304.411 - Fish attractor, spawning, and habitat structures.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Fish attractor... STRUCTURES AND OTHER ALTERATIONS Miscellaneous § 1304.411 Fish attractor, spawning, and habitat structures. Fish attractors constitute potential obstructions and require TVA approval. (a) Fish attractors may be...
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18 CFR 1304.411 - Fish attractor, spawning, and habitat structures.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Fish attractor, spawning... OTHER ALTERATIONS Miscellaneous § 1304.411 Fish attractor, spawning, and habitat structures. Fish attractors constitute potential obstructions and require TVA approval. (a) Fish attractors may be constructed...
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18 CFR 1304.411 - Fish attractor, spawning, and habitat structures.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Fish attractor... STRUCTURES AND OTHER ALTERATIONS Miscellaneous § 1304.411 Fish attractor, spawning, and habitat structures. Fish attractors constitute potential obstructions and require TVA approval. (a) Fish attractors may be...
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18 CFR 1304.411 - Fish attractor, spawning, and habitat structures.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Fish attractor... STRUCTURES AND OTHER ALTERATIONS Miscellaneous § 1304.411 Fish attractor, spawning, and habitat structures. Fish attractors constitute potential obstructions and require TVA approval. (a) Fish attractors may be...
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18 CFR 1304.411 - Fish attractor, spawning, and habitat structures.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Fish attractor... STRUCTURES AND OTHER ALTERATIONS Miscellaneous § 1304.411 Fish attractor, spawning, and habitat structures. Fish attractors constitute potential obstructions and require TVA approval. (a) Fish attractors may be...
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MODELING PHYSICAL HABITAT PARAMETERS
Salmonid populations can be affected by alterations in stream physical habitat. Fish productivity is determined by the stream's physical habitat structure ( channel form, substrate distribution, riparian vegetation), water quality, flow regime and inputs from the watershed (sedim...
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Indicators: Physical Habitat Complexity
Physical habitat complexity measures the amount and variety of all types of cove at the water’s edge in lakes. In general, dense and varied shoreline habitat is able to support more diverse communities of aquatic life.
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Design and logistics of integrated spacecraft/lander lunar habitat concepts
NASA Technical Reports Server (NTRS)
Hypes, Warren D.; Wright, Robert L.; Gould, Marston J.; Lovelace, U. M.
1991-01-01
Integrated spacecraft/lander combinations have been designed to provide a support structure for thermal and galactic radiation shielding for three initial lunar habitat concepts. Integrating the support structure with the habitat reduces the logistics requirements for the implantation of the initial base. The designs are simple, make use of existing technologies, and minimize the amount of lunar surface preparation and crew activity. The design facilitates continued use of all elements in the development of a permanent lunar base and precludes the need for an entirely different structure of larger volume and increased complexity of implantation. This design philosophy, coupled with the reduced logistics, increases overall cost effectiveness.
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Carlisle, Aaron B.; Goldman, Kenneth J.; Litvin, Steven Y.; Madigan, Daniel J.; Bigman, Jennifer S.; Swithenbank, Alan M.; Kline, Thomas C.; Block, Barbara A.
2015-01-01
Ontogenetic changes in habitat are driven by shifting life-history requirements and play an important role in population dynamics. However, large portions of the life history of many pelagic species are still poorly understood or unknown. We used a novel combination of stable isotope analysis of vertebral annuli, Bayesian mixing models, isoscapes and electronic tag data to reconstruct ontogenetic patterns of habitat and resource use in a pelagic apex predator, the salmon shark (Lamna ditropis). Results identified the North Pacific Transition Zone as the major nursery area for salmon sharks and revealed an ontogenetic shift around the age of maturity from oceanic to increased use of neritic habitats. The nursery habitat may reflect trade-offs between prey availability, predation pressure and thermal constraints on juvenile endothermic sharks. The ontogenetic shift in habitat coincided with a reduction of isotopic niche, possibly reflecting specialization upon particular prey or habitats. Using tagging data to inform Bayesian isotopic mixing models revealed that adult sharks primarily use neritic habitats of Alaska yet receive a trophic subsidy from oceanic habitats. Integrating the multiple methods used here provides a powerful approach to retrospectively study the ecology and life history of migratory species throughout their ontogeny. PMID:25621332
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Michael E. Akresh; David I. King; Brad C. Timm; Robert T. Brooks
2017-01-01
Eastern Hognose Snakes (Heterodon platirhinos) are considered a species of conservation concern in the northeast United States because of their association with rare and declining habitats such as pine barrens and shrublands. These are disturbance-dependent habitats that currently require management to persist. We studied Eastern Hognose Snakes on...
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Valentine, Page C.; Cochrane, Guy R.; Scanlon, Kathryn M.
2003-01-01
The National Marine Sanctuary System requires seabed and habitat maps to serve as a basis for managing sanctuary resources and for conducting research. NOAA, the agency that manages the sanctuaries, and the USGS have conducted mapping projects in three sanctuaries (Stellwagen Bank NMS, Flower Garden Banks NMS, and Channel Islands NMS) with an emphasis on collaboration of geologists and biologists from the two agencies and from academic institutions. Mapping of seabed habitats is a developing field that requires the integration of geologic and biologic studies and the use of swath imaging techniques such as multibeam and sidescan sonar. Major products of swath mapping are shaded-relief topographic imagery which shows seabed features in great detail, and backscatter imagery which provides an indication of the types of materials that constitute the seabed. Sea floor images provide an excellent basis for conducting the groundtruthing studies (using video, photo, and sampling techniques) that are required to collect the data necessary for making meaningful interpretative maps of the seabed. The compilation of interpretive maps showing seabed environments and habitats also requires the development of a sea floor classification system that will be a basis for comparing, managing, and researching characteristic areas of the seabed. Seabed maps of the sanctuaries are proving useful for management and research decisions that address commercial and recreational fishing, habitat disturbance, engineering projects, tourism, and cultural resources.
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Architecture and life support systems for a rotating space habitat
NASA Astrophysics Data System (ADS)
Misra, Gaurav
Life Support Systems are critical to sustain human habitation of space over long time periods. As orbiting space habitats become operational in the future, support systems such as atmo-sphere, food, water etc. will play a very pivotal role in sustaining life. To design a long-duration space habitat, it's important to consider the full gamut of human experience of the environment. Long-term viability depends on much more than just the structural or life support efficiency. A space habitat isn't just a machine; it's a life experience. To be viable, it needs to keep the inhabitants satisfied with their condition. This paper provides conceptual research on several key factors that influence the growth and sustainability of humans in a space habitat. Apart from the main life support system parameters, the architecture (both interior and exterior) of the habitat will play a crucial role in influencing the liveability in the space habitat. In order to ensure the best possible liveability for the inhabitants, a truncated (half cut) torus is proposed as the shape of the habitat. This structure rotating at an optimum rpm will en-sure 1g pseudo gravity to the inhabitants. The truncated torus design has several advantages over other proposed shapes such as a cylinder or a sphere. The design provides minimal grav-ity variation (delta g) in the living area, since its flat outer pole ensures a constant gravity. The design is superior in economy of structural and atmospheric mass. Interior architecture of the habitat addresses the total built environment, drawing from diverse disciplines includ-ing physiology, psychology, and sociology. Furthermore, factors such as line of sight, natural sunlight and overhead clearance have been discussed in the interior architecture. Substantial radiation shielding is also required in order to prevent harmful cosmic radiations and solar flares from causing damage to inhabitants. Regolith shielding of 10 tons per meter square is proposed for the
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Lunar Architecture Team - Phase 2 Habitat Volume Estimation: "Caution When Using Analogs"
NASA Technical Reports Server (NTRS)
Rudisill, Marianne; Howard, Robert; Griffin, Brand; Green, Jennifer; Toups, Larry; Kennedy, Kriss
2008-01-01
The lunar surface habitat will serve as the astronauts' home on the moon, providing a pressurized facility for all crew living functions and serving as the primary location for a number of crew work functions. Adequate volume is required for each of these functions in addition to that devoted to housing the habitat systems and crew consumables. The time constraints of the LAT-2 schedule precluded the Habitation Team from conducting a complete "bottoms-up" design of a lunar surface habitation system from which to derive true volumetric requirements. The objective of this analysis was to quickly derive an estimated total pressurized volume and pressurized net habitable volume per crewmember for a lunar surface habitat, using a principled, methodical approach in the absence of a detailed design. Five "heuristic methods" were used: historical spacecraft volumes, human/spacecraft integration standards and design guidance, Earth-based analogs, parametric "sizing" tools, and conceptual point designs. Estimates for total pressurized volume, total habitable volume, and volume per crewmember were derived using these methods. All method were found to provide some basis for volume estimates, but values were highly variable across a wide range, with no obvious convergence of values. Best current assumptions for required crew volume were provided as a range. Results of these analyses and future work are discussed.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Beiningen, Kirk T.
The author reports on progress from April 1994 through March 1995 of research on white sturgeon in the lower Columbia River. The study began in July 1986 and is a cooperative effort of federal, state and tribal fisheries entities to determine the (1) the status and habitat requirements, and (2) the effects of mitigative measures on productivity of white sturgeon populations in the lower Columbia River. This report describes activities conducted during the third year of this contract's second phase. Information was collected, analyzed, and evaluated on sub-adult and adult life histories, population dynamics, quantity and quality of habitat, andmore » production enhancement strategies. The report is divided into sections that evaluate success of developing and implementing a management plan for white sturgeon; evaluate growth, mortality, and contributions to fisheries of juvenile white sturgeon transplanted from areas downstream; describe the life history and population dynamics of sub-adult a nd adult white sturgeon; define habitat requirements for spawning and rearing of white sturgeon and quantify the extent of habitat available; describe reproductive and early life history characteristics of white sturgeon; and quantify physical habitat used by spawning and rearing white sturgeon in the free-flowing portion of the Columbia River.« less
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Kang, Dongwei; Wang, Xiaorong; Li, Shuang; Li, Junqing
2017-06-15
Artificial restoration is an important way to restore forests, but little is known about its effect on the habitat restoration of the giant panda. In the present study, we investigated the characteristics of artificial forest in the Wanglang Nature Reserve to determine whether through succession it has formed a suitable habitat for the giant panda. We compared artificial forest characteristics with those of natural habitat used by the giant panda. We found that the dominant tree species in artificial forest differed from those in the natural habitat. The artificial forest had lower plant species richness and diversity in the tree and shrub layers than did the latter, and its community structure was characterized by smaller tree and bamboo sizes, and fewer and lower bamboo clumps, but more trees and larger shrub sizes. The typical community collocation of artificial forest was a "Picea asperata + no-bamboo" model, which differs starkly from the giant panda's natural habitat. After several years of restoration, the artificial forest has failed to become a suitable habitat for the giant panda. Therefore, a simple way of planting individual trees cannot restore giant panda habitat; instead, habitat restoration should be based on the habitat requirements of the giant panda.
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Li, Hongqun; Yue, Bisong; Lian, Zhenmin; Zhao, Hongfeng; Zhao, Delong; Xiao, Xiangming
2012-09-01
A detailed understanding of the habitat needs of brown eared pheasants (Crossoptilon mantchuricum) is essential for conserving the species. We carried out field surveys in the Huanglong Mountains of Shaanxi Province, China, from March to June in 2007 and 2008. We arrayed a total of 206 grid plots (200 × 200 m) along transects in 2007 and 2008 and quantified a suite of environmental variables for each one. In the optimal logistic regression model, the most important variables for brown eared pheasants were slope degree, tree cover, distance to nearest water, cover and depth of fallen leaves. Hosmer and Leweshow goodness-of-fit tests explained that logistic models for the species were good fits. The model suggested that spring habitat selection of the brown eared pheasant was negatively related to distance to nearest water and slope degree, and positively to cover of trees and cover and depth of fallen leaves. In addition, the observed detected and undetected grids in 2007 did not show significant differences with predictions based on the model. These results showed that the model could well predict the habitat selection of brown eared pheasants. Based on these predictive models, we suggest that habitat management plans incorporating this new information can now focus more effectively on restrictions on the number of tourists entering the nature reserve, prohibition of firewood collection, livestock grazing, and medicinal plant harvesting by local residents in the core areas, protection of mixed forest and sources of the permanent water in the reserve, and use of alternatives to firewood.
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Radial Internal Material Handling System (RIMS) for Circular Habitat Volumes
NASA Technical Reports Server (NTRS)
Howe, Alan S.; Haselschwardt, Sally; Bogatko, Alex; Humphrey, Brian; Patel, Amit
2013-01-01
On planetary surfaces, pressurized human habitable volumes will require a means to carry equipment around within the volume of the habitat, regardless of the partial gravity (Earth, Moon, Mars, etc.). On the NASA Habitat Demonstration Unit (HDU), a vertical cylindrical volume, it was determined that a variety of heavy items would need to be carried back and forth from deployed locations to the General Maintenance Work Station (GMWS) when in need of repair, and other equipment may need to be carried inside for repairs, such as rover parts and other external equipment. The vertical cylindrical volume of the HDU lent itself to a circular overhead track and hoist system that allows lifting of heavy objects from anywhere in the habitat to any other point in the habitat interior. In addition, the system is able to hand-off lifted items to other material handling systems through the side hatches, such as through an airlock. The overhead system consists of two concentric circle tracks that have a movable beam between them. The beam has a hoist carriage that can move back and forth on the beam. Therefore, the entire system acts like a bridge crane curved around to meet itself in a circle. The novelty of the system is in its configuration, and how it interfaces with the volume of the HDU habitat. Similar to how a bridge crane allows coverage for an entire rectangular volume, the RIMS system covers a circular volume. The RIMS system is the first generation of what may be applied to future planetary surface vertical cylinder habitats on the Moon or on Mars.
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Cornell, K.L.; Donovan, T.M.
2010-01-01
Understanding how spatial habitat patterns influence abundance and dynamics of animal populations is a primary goal in landscape ecology. We used an information-theoretic approach to investigate the association between habitat patterns at multiple spatial scales and demographic patterns for black-throated blue warblers (Dendroica caerulescens) at 20 study sites in west-central Vermont, USA from 2002 to 2005. Sites were characterized by: (1) territory-scale shrub density, (2) patch-scale shrub density occurring within 25 ha of territories, and (3) landscape-scale habitat patterns occurring within 5 km radius extents of territories. We considered multiple population parameters including abundance, age ratios, and annual fecundity. Territory-scale shrub density was most important for determining abundance and age ratios, but landscape-scale habitat structure strongly influenced reproductive output. Sites with higher territory-scale shrub density had higher abundance, and were more likely to be occupied by older, more experienced individuals compared to sites with lower shrub density. However, annual fecundity was higher on sites located in contiguously forested landscapes where shrub density was lower than the fragmented sites. Further, effects of habitat pattern at one spatial scale depended on habitat conditions at different scales. For example, abundance increased with increasing territory-scale shrub density, but this effect was much stronger in fragmented landscapes than in contiguously forested landscapes. These results suggest that habitat pattern at different spatial scales affect demographic parameters in different ways, and that effects of habitat patterns at one spatial scale depends on habitat conditions at other scales. ?? Springer Science+Business Media B.V. 2009.
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Selecting compact habitat reserves for species with differential habitat size needs
Vladimir Marianov; Charles ReVelle; Stephanie Snyder
2008-01-01
We propose a model for the design of protected habitat reserves, which maximizes the number of species represented at least once in a limited set of reserved sites or parcels. Most models for reserve design do not differentiate eligible habitat sites by their size. Also, they assume that protection is guaranteed through the selection of one site for any species, not...
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Range-wide assessment of habitat suitability for Roanoke logperch (Percina rex).
DOT National Transportation Integrated Search
2007-01-01
The Roanoke logperch (Percina rex) is a federally endangered darter endemic to Virginia. Knowledge of its distribution and habitat requirements is limited. Before this study, it was known to occur in the Smith, Pigg, Roanoke and Nottoway river waters...