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Sample records for bull trout recruitment

  1. Kootenai River Fisheries Investigations; Rainbow and Bull Trout Recruitment, 2002-2003 Annual Report.

    SciTech Connect

    Walters, Jody P.

    2004-01-01

    Rainbow trout Oncorhynchus mykiss provide the most important sport fishery in the Kootenai River, Idaho, but densities and catch rates are low. Low recruitment is one possible factor limiting the rainbow trout population. Bull trout Salvelinus confluentus also exist in the Kootenai River, but little is known about this population. Research reported here addresses the following objectives for the Kootenai River, Idaho: increase rainbow trout recruitment, identify rainbow and bull trout spawning tributaries and migration timing, establish baseline data on bull trout redd numbers in tributaries, and improve the rainbow trout population size structure. Six adult rainbow trout were moved to spawning habitat upstream of a potential migration barrier on Caboose Creek, but numbers of redds and age-0 out-migrants did not appear to increase relative to a reference stream. Measurements taken on the Moyie River indicated the gradient is inadequate to deliver suitable flows to a proposed rainbow trout spawning channel. Summer water temperatures measured in the Deep Creek drainage sometimes exceeded 24 C, higher than those reported as suitable for rainbow trout. Radio-tagged rainbow trout were located in Boulder Creek during the spring spawning season, and bull trout were located in the Moyie River and O'Brien Creek, Montana in the fall. Bull trout spawning migration timing was related to increases in Kootenai River flows. Bull trout redd surveys documented 19 redds on Boulder Creek and North and South Callahan creeks. Fall 2002 electrofishing showed that the Kootenai River rainbow trout proportional stock density was 54, higher than prior years when more liberal fishing regulations were in effect. Boulder Creek produces the highest number of age-0 rainbow trout out-migrants upstream of Bonners Ferry, but the survival rate of these out-migrants upon reaching the Kootenai River is unknown. Determining juvenile survival rates and sources of mortality could aid management efforts

  2. Kootenai River Fisheries Investigations; Rainbow and Bull Trout Recruitment, 1999 Annual Report.

    SciTech Connect

    Walters, Jody P.; Downs, Christopher C.

    2001-08-01

    Our 1999 objectives were to determine sources of rainbow trout Oncorhynchus mykiss and bull trout Salvelinus confluentus spawning and recruitment in the Idaho reach of the Kootenai River. We used a rotary-screw trap to capture juvenile trout to determine age at out-migration and to estimate total out-migration from the Boundary Creek drainage to the Kootenai River. The out-migrant estimate for March through August 1999 was 1,574 (95% C. I. = 825-3,283) juvenile rainbow trout. Most juveniles out-migrated at age-2 and age-3. No out-migrating bull trout were caught. Five of 17 rainbow trout radio-tagged in Idaho migrated upstream into Montana waters during the spawning season. Five bull trout originally radio-tagged in O'Brien Creek, Montana in early October moved downstream into Idaho and British Columbia by mid-October. Annual angler exploitation for the rainbow trout population upstream of Bonners Ferry, Idaho was estimated to be 58%. Multi-pass depletion estimates for index reaches of Caboose, Curley, and Debt creeks showed 0.20, 0.01, and 0.13 rainbow trout juveniles/m{sup 2}, respectively. We estimated rainbow trout (180-415 mm TL) standing stock of 1.6 kg/ha for the Hemlock Bar reach (29.4 ha) of the Kootenai River, similar to the 1998 estimate. Recruitment of juvenile rainbow and bull trout from Idaho tributaries is not sufficient to be the sole source of subsequent older fish in the mainstem Kootenai River. These populations are at least partly dependent on recruitment from Montana waters. The low recruitment and high exploitation rate may be indicators of a rainbow trout population in danger of further decline.

  3. Kootenai River Fisheries Investigations; Rainbow and Bull Trout Recruitment, 2003-2004 Annual Report.

    SciTech Connect

    Walters, Jody P.

    2005-08-01

    Rainbow trout Oncorhynchus mykiss provide the most important sport fishery in the Kootenai River, Idaho, but densities and catch rates are low. Low recruitment is one possible factor limiting the rainbow trout population. Bull trout Salvelinus confluentus also exist in the Kootenai River, but little is known about this population. Research reported here addresses the following objectives for the Kootenai River, Idaho: identify sources of rainbow and bull trout recruitment, monitor the rainbow trout population size structure to evaluate regulation changes initiated in 2002, and identify factors potentially limiting rainbow trout recruitment. A screw trap was used to estimate juvenile redband and bull trout out-migration from the Callahan Creek drainage, and electrofishing was conducted to estimate summer densities of bull trout rearing in the Idaho portion of the drainage. An estimated 1,132 juvenile redband trout and 68 juvenile bull trout out-migrated from Callahan Creek to the Kootenai River from April 7 through July 15, 2003. Densities of bull trout {ge} age-1 in North and South Callahan creeks ranged from 1.6 to 7.7 fish/100m{sup 2} in August. Bull trout redd surveys were conducted in North and South Callahan creeks, Boulder Creek, and Myrtle Creek. Thirty-two bull trout redds were located in North Callahan Creek, while 10 redds were found in South Callahan Creek. No redds were found in the other two streams. Modeling of culverts in the Deep Creek drainage identified two as upstream migration barriers, preventing rainbow trout from reaching spawning and rearing habitat. Water temperature monitoring in Deep Creek identified two sites where maximum temperatures exceeded those suitable for rainbow trout. Boulder Creek produces the most rainbow trout recruits to the Kootenai River in Idaho upstream of Deep Creek, but may be below carrying capacity for rearing rainbow trout due to nutrient limitations. Monthly water samples indicate Boulder Creek is nutrient limited

  4. Status of Oregon's Bull Trout.

    SciTech Connect

    Buchanan, David V.; Hanson, Mary L.; Hooton, Robert M.

    1997-10-01

    Limited historical references indicate that bull trout Salvelinus confluentus in Oregon were once widely spread throughout at least 12 basins in the Klamath River and Columbia River systems. No bull trout have been observed in Oregon's coastal systems. A total of 69 bull trout populations in 12 basins are currently identified in Oregon. A comparison of the 1991 bull trout status (Ratliff and Howell 1992) to the revised 1996 status found that 7 populations were newly discovered and 1 population showed a positive or upgraded status while 22 populations showed a negative or downgraded status. The general downgrading of 32% of Oregon's bull trout populations appears largely due to increased survey efforts and increased survey accuracy rather than reduced numbers or distribution. However, three populations in the upper Klamath Basin, two in the Walla Walla Basin, and one in the Willamette Basin showed decreases in estimated population abundance or distribution.

  5. Critical swimming speeds of wild bull trout

    USGS Publications Warehouse

    Mesa, M.G.; Weiland, L.K.; Zydlewski, G.B.

    2004-01-01

    We estimated the critical swimming speeds (Ucrit) of wild bull trout at 6??, 11??, and 15??C in laboratory experiments. At 11??C, 5 fish ranging from 11 to 19 cm in length had a mean Ucrit of 48.24 cm/s or 3.22 body lengths per second (BL/s). Also at 11??C , 6 fish from 32 to 42 cm had a mean Ucrit of 73.99 cm/s or 2.05 BL/s. At 15??C, 5 fish from 14 to 23 cm had a mean Ucrit of 54.66 cm/s or 2.88 BL/s. No fish successfully swam at 6??C. Swim speed was significantly influenced by fish length. Many bull trout performed poorly in our enclosed respirometers: of 71 Ucrit tests we attempted, only the 16 described above were successful. Bull trout that refused to swim held station within tunnels by using their pectoral fins as depressors, or they rested and later became impinged against a downstream screen. Several common techniques did not stimulate consistent swimming activity in these fish. Our estimates of U crit for bull trout provide an understanding of their performance capacity and will be useful in modeling efforts aimed at improving fish passage structures. We recommend that fishway or culvert designers concerned with bull trout passage maintain velocities within their structures at or below our estimates of Ucrit, thus taking a conservative approach to ensuring that these fish can ascend migratory obstacles safely.

  6. Diet overlap of top-level predators in recent sympatry: bull trout and nonnative lake trout

    USGS Publications Warehouse

    Guy, Christopher S.; McMahon, Thomas E.; Fredenberg, Wade A.; Smith, Clinton J.; Garfield, David W.; Cox, Benjamin S.

    2011-01-01

    The establishment of nonnative lake trout Salvelinus namaycush in lakes containing lacustrine–adfluvial bull trout Salvelinus confluentus often results in a precipitous decline in bull trout abundance. The exact mechanism for the decline is unknown, but one hypothesis is related to competitive exclusion for prey resources. We had the rare opportunity to study the diets of bull trout and nonnative lake trout in Swan Lake, Montana during a concomitant study. The presence of nonnative lake trout in Swan Lake is relatively recent and the population is experiencing rapid population growth. The objective of this study was to evaluate the diets of bull trout and lake trout during the early expansion of this nonnative predator. Diets were sampled from 142 bull trout and 327 lake trout during the autumn in 2007 and 2008. Bull trout and lake trout had similar diets, both consumed Mysis diluviana as the primary invertebrate, especially at juvenile stages, and kokanee Oncorhynchus nerka as the primary vertebrate prey, as adults. A diet shift from primarily M. diluviana to fish occurred at similar lengths for both species, 506 mm (476–545 mm, 95% CI) for bull trout and 495 mm (470–518 mm CI) for lake trout. These data indicate high diet overlap between these two morphologically similar top-level predators. Competitive exclusion may be a possible mechanism if the observed overlap remains similar at varying prey densities and availability.

  7. Protocol for determining bull trout presence

    USGS Publications Warehouse

    Peterson, James; Dunham, Jason B.; Howell, Philip; Thurow, Russell; Bonar, Scott

    2002-01-01

    The Western Division of the American Fisheries Society was requested to develop protocols for determining presence/absence and potential habitat suitability for bull trout. The general approach adopted is similar to the process for the marbled murrelet, whereby interim guidelines are initially used, and the protocols are subsequently refined as data are collected. Current data were considered inadequate to precisely identify suitable habitat but could be useful in stratifying sampling units for presence/absence surveys. The presence/absence protocol builds on previous approaches (Hillman and Platts 1993; Bonar et al. 1997), except it uses the variation in observed bull trout densities instead of a minimum threshold density and adjusts for measured differences in sampling efficiency due to gear types and habitat characteristics. The protocol consists of: 1. recommended sample sizes with 80% and 95% detection probabilities for juvenile and resident adult bull trout for day and night snorkeling and electrofishing adjusted for varying habitat characteristics for 50m and 100m sampling units, 2. sampling design considerations, including possible habitat characteristics for stratification, 3. habitat variables to be measured in the sampling units, and 3. guidelines for training sampling crews. Criteria for habitat strata consist of coarse, watershed-scale characteristics (e.g., mean annual air temperature) and fine-scale, reach and habitat-specific features (e.g., water temperature, channel width). The protocols will be revised in the future using data from ongoing presence/absence surveys, additional research on sampling efficiencies, and development of models of habitat/species occurrence.

  8. Monitor and Protect Wigwam River Bull Trout for Koocanusa Reservoir; Skookumchuck Creek Juvenile Bull Trout and Fish Habitat Monitoring Program, Annual Report 2002.

    SciTech Connect

    Cope, R.

    2003-06-01

    The Skookumchuck Creek juvenile bull trout (Salvelinus confluentus) and fish habitat-monitoring program is a co-operative initiative of the British Columbia Ministry of Water, Land, and Air Protection and Bonneville Power Administration. This project was commissioned in planning for fish habitat protection and forest development within the Skookumchuck Creek watershed and was intended to expand upon similar studies initiated within the Wigwam River from 2000 to 2002. The broad intent is to develop a better understanding of juvenile bull trout and Westslope cutthroat trout recruitment and the ongoing hydrologic and morphologic processes, especially as they relate to spawning and rearing habitat quality. The 2002 project year represents the first year of a long-term bull trout-monitoring program with current studies focused on collecting baseline information. This report provides a summary of results obtained to date. Bull trout represented 72.4% of the catch. Fry dominated the catch because site selection was biased towards electrofishing sample sites which favored high bull trout fry capture success. The mean density of all juvenile bull trout was estimated to be 6.6 fish/100m{sup 2}. This represents one-half the densities reported for the 2002 Wigwam River enumeration program, even though enumeration of bull trout redds was an order of magnitude higher for the Wigwam River. Typically, areas with combined fry and juvenile densities greater than 1.5 fish per 100 m{sup 2} are cited as critical rearing areas. Trends in abundance appeared to be related to proximity to spawning areas, bed material size, and water depth. Cover components utilized by juvenile and adult bull trout and cutthroat trout were interstices, boulder, depth, overhead vegetation and LWD. The range of morphological stream types encompass the stable and resilient spectrum (C3(1), C3 and B3c). The Skookumchuck can be generalized as a slightly entrenched, meandering, riffle-pool, cobble dominated

  9. Are brown trout replacing or displacing bull trout populations in a changing climate?

    USGS Publications Warehouse

    Al-Chokhachy, Robert K.; Schmetterling, David A.; Clancy, Chris; Saffel, Pat; Kovach, Ryan; Nyce, Leslie; Liermann, Brad; Fredenberg, Wade A.; Pierce, Ron

    2016-01-01

    Understanding how climate change may facilitate species turnover is an important step in identifying potential conservation strategies. We used data from 33 sites in western Montana to quantify climate associations with native bull trout (Salvelinus confluentus) and non-native brown trout (Salmo trutta) abundance and population growth rates (λ). We estimated λ using exponential growth state space models and delineated study sites based on bull trout use for either Spawning and Rearing (SR) or Foraging, Migrating, and Overwintering (FMO) habitat. Bull trout abundance was negatively associated with mean August stream temperatures within SR habitat (r = -0.75). Brown trout abundance was generally highest at temperatures between 12 and 14°C. We found bull trout λ were generally stable at sites with mean August temperature below 10°C but significantly decreasing, rare, or extirpated at 58% of the sites with temperatures exceeding 10°C. Brown trout λ were highest in SR and sites with temperatures exceeding 12°C. Declining bull trout λs at sites where brown trout were absent suggests brown trout are likely replacing bull trout in a warming climate.

  10. Wigwam River Juvenile Bull Trout and Fish Habitat Monitoring Program : 2001 Data Report.

    SciTech Connect

    Cope, R.S.; Morris, K.J.; Bisset, J.E.

    2002-03-01

    The Wigwam River juvenile bull trout and fish habitat monitoring program is a co-operative initiative of the British Columbia Ministry of Water, Land, and Air Protection and Bonneville Power Administration. The Wigwam River has been characterized as the single most important bull trout spawning stream in the Kootenay Region. This report provides a summary of results obtained during the second year (2001) of the juvenile bull trout enumeration and fish habitat assessment program. This project was commissioned in planning for fish habitat protection and forest development within the upper Wigwam River valley. The broad intent is to develop a better understanding of juvenile bull trout and Westslope cutthroat trout recruitment and the ongoing hydrologic and morphologic processes in the upper Wigwam River, especially as they relate to spawning and rearing habitat quality. Five permanent sampling sites were established August 2000 in the Wigwam river drainage (one site on Bighorn Creek and four sites on the mainstem Wigwam River). At each site, juvenile (0{sup +}, 1{sup +} and 2{sup +} age classes) fish densities and stream habitat conditions were measured over two stream meander wavelengths. Bull trout represented 95.1% of the catch and the mean density of juvenile bull trout was estimated to be 20.7 fish/100m{sup 2} (range 0.9 to 24.0 fish/100m{sup 2}). This compares to 17.2 fish/100m{sup 2} (+20%) for the previous year. Fry (0{sup +}) dominated the catch and this was a direct result of juvenile bull trout ecology and habitat partitioning among life history stages. Site selection was biased towards sample sites which favored high bull trout fry capture success. Comparison of fry density estimates replicated across both the preliminary survey (1997) and the current study (Cope and Morris 2001) illustrate the stable nature of these high densities. Bull trout populations have been shown to be extremely susceptible to habitat degradation and over-harvest and are

  11. Use of cover habitat by bull trout Salvelinus confluentus and lake trout Salvelinus namaycush in a laboratory environment

    USGS Publications Warehouse

    Meeuwig, Michael H.; Guy, Christopher S.; Fredenberg, Wade A.

    2011-01-01

    Lacustrine-adfluvial bull trout, Salvelinus confluentus, migrate from spawning and rearing streams to lacustrine environments as early as age 0. Within lacustrine environments, cover habitat pro- vides refuge from potential predators and is a resource that is competed for if limiting. Competitive inter- actions between bull trout and other species could result in bull trout being displaced from cover habitat, and bull trout may lack evolutionary adaptations to compete with introduced species, such as lake trout, Salvelinus namaycush. A laboratory experiment was performed to examine habitat use and interactions for cover by juvenile (i.e., <80 mm total length) bull trout and lake trout. Differences were observed between bull trout and lake trout in the proportion of time using cover (F1,22.6=20.08, P<0.001) and bottom (F1,23.7 = 37.01, P < 0.001) habitat, with bull trout using cover and bottom habitats more than lake trout. Habitat selection ratios indicated that bull trout avoided water column habitat in the presence of lake trout and that lake trout avoided bottom habitat. Intraspecific and interspecific agonistic interactions were infrequent, but approximately 10 times greater for intraspecific inter- actions between lake trout. Results from this study provide little evidence that juvenile bull trout and lake trout compete for cover, and that species-specific differences in habitat use and selection likely result in habitat partitioning between these species.

  12. Spawning and rearing behavior of bull trout in a headwaterlake ecosystem

    USGS Publications Warehouse

    Lora B. Tennant,; Gresswell, Bob; Guy, Christopher S.; Michael H. Meeuwig,

    2015-01-01

    Numerous life histories have been documented for bull trout Salvelinus confluentus. Lacustrine-adfluvial bull trout populations that occupy small, headwater lake ecosystems and migrate short distances to natal tributaries to spawn are likely common; however, much of the research on potamodromous bull trout has focused on describing the spawning and rearing characteristics of bull trout populations that occupy large rivers and lakes and make long distance spawning migrations to natal headwater streams. This study describes the spawning and rearing characteristics of lacustrine-adfluvial bull trout in the Quartz Lake drainage, Glacier National Park, USA, a small headwater lake ecosystem. Many spawning and rearing characteristics of bull trout in the Quartz Lake drainage are similar to potamodromous bull trout that migrate long distances. For example, subadult bull trout distribution was positively associated with slow-water habitat unit types and maximum wetted width, and negatively associated with increased stream gradient. Bull trout spawning also occurred when water temperatures were between 5 and 9 °C, and redds were generally located in stream segments with low stream gradient and abundant gravel and cobble substrates. However, this study also elucidated characteristics of bull trout biology that are not well documented in the literature, but may be relatively widespread and have important implications regarding general characteristics of bull trout ecology, use of available habitat by bull trout, and persistence of lacustrine-adfluvial bull trout in small headwater lake ecosystems.

  13. Swimming endurance of bull trout, lake trout, arctic char, and rainbow trout following challenge with Renibacterium salmoninarum

    USGS Publications Warehouse

    Jones, D.T.; Moffitt, C.M.

    2004-01-01

    We tested the swimming endurance of juvenile bull trout Salvelinus confluentus, lake trout S. namaycush, Arctic char S. alpinus, and rainbow trout Oncorhynchus mykiss at 9??C and 15??C to determine whether sublethal infection from a moderate challenge of Renibacterium salmoninarum administered months before testing affected the length of time fish could maintain a swimming speed of 5-6 body lengths per second in an experimental flume. Rainbow trout and Arctic char swam longer in trials than did bull trout or lake trout, regardless of challenge treatment. When we tested fish 14-23 weeks postchallenge, we found no measurable effect of R. salmoninarum on the swimming endurance of the study species except for bull trout, which showed a mixed response. We conducted additional trials with bull trout 5-8 weeks postchallenge to determine whether increasing the challenge dose would affect swimming endurance and hematocrit. In those tests, bull trout with clinical signs of disease and those exposed to the highest challenge doses had significantly reduced swimming endurance compared with unchallenged control fish. Fish hematocrit levels measured at the end of all swimming endurance tests varied among species and between test temperatures, and patterns were not always consistent between challenged and control fish.

  14. Genetic Inventory of Bull Trout and Westslope Cutthroat Trout in Pend Oreille Subbasin, 2003-2004 Annual Report.

    SciTech Connect

    Olson, Jason; Maroney, Joseph R.; Andersen, Todd

    2004-11-01

    In 2003, the Kalispel Natural Resource Department (KNRD) collected tissue samples for genetic analysis from 209 bull trout and 1,276 westslope cutthroat. The Washington Department of Fish and Wildlife developed and applied microsatellite DNA screening protocols for the analysis of bull trout at 13 loci and 24 loci for cutthroat trout. This project will continue collection and analysis of additional samples next year. At that time, a final annual report will be compiled for the three-year study that will describe the genetic characteristics for bull trout and westslope cutthroat trout. The extent of hybridization of bull trout (with brook trout) and westslope cutthroat trout (with Yellowstone cutthroat trout and rainbow trout) in the Priest Lake and Lower Pend Oreille subbasins will also be examined.

  15. Genetic Inventory of Bull Trout and Westslope Cutthroat Trout in the Pend Oreille Subbasin, 2002-2003 Annual Report.

    SciTech Connect

    Maroney, Joseph R.; Shaklee, James B.; Young, Sewall F.

    2003-10-01

    In 2002, the Kalispel Natural Resource Department (KNRD) collected tissue samples for genetic analysis from 280 bull trout and 940 westslope cutthroat. The Washington Department of Fish and Wildlife developed and applied microsatellite DNA screening protocols for the analysis of bull trout at 13 loci and 24 loci for cutthroat trout. This project will continue collection and analysis of additional samples for the next 2 years. At that time, a final annual report will be compiled for the three-year study that will describe the genetic characteristics for bull trout and westslope cutthroat trout. The extent of hybridization of bull trout (with brook trout) and westslope cutthroat trout (with Yellowstone cutthroat trout and rainbow trout) in the Priest Lake and Lower Pend Oreille subbasins will also be examined.

  16. Demographic characteristics of an adfluvial bull trout population in Lake Pend Oreille, Idaho

    USGS Publications Warehouse

    McCubbins, Jonathan L; Hansen, Michael J.; DosSantos, Joseph M; Dux, Andrew M

    2016-01-01

    Introductions of nonnative species, habitat loss, and stream fragmentation have caused the Bull Trout Salvelinus confluentus to decline throughout much of its native distribution. Consequently, in June 1998, the Bull Trout was listed under the U.S. Endangered Species Act as threatened. The Bull Trout has existed in Lake Pend Oreille and its surrounding tributaries since the last ice age, and the lake once supported a world-renowned Bull Trout fishery. To quantify the current status of the Bull Trout population in Lake Pend Oreille, Idaho, we compared the mean age, growth, maturity, and abundance with reports in a study conducted one decade earlier. Abundance was estimated by mark–recapture for Bull Trout caught in trap nets and gill nets set in Lake Pend Oreille during ongoing suppression netting of Lake Trout S. namaycushin 2007–2008. Bull Trout sampled in 2006–2008 were used to estimate age structure, survival, growth, and maturity. Estimated Bull Trout abundance was similar to that estimated one decade earlier in Lake Pend Oreille. Bull Trout residing in Lake Pend Oreille between 2006 and 2008 were between ages 4 and 14 years; their growth was fastest between ages 1 and 2 and slowed thereafter. Male and female Bull Trout matured at a similar age, but females grew faster than males, thereby maturing at a larger size. Our findings suggest that management has effectively addressed current threats to increase the likelihood of long-term persistence of the Bull Trout population in Lake Pend Oreille.

  17. Bull Trout Life History, Genetics, Habitat Needs, and Limiting Factors in Central and Northeast Oregon. Annual Report 1996.

    SciTech Connect

    Bellerud, Blane L.; Gunckel, Stephanie; Hemmingsen, Alan R.; Buchanan, David V.; Howell, Philip J.

    1997-10-01

    This study is part of a multi-year research project studying aspects of bull trout life history, ecology and genetics. This report covers the activities of the project in 1996. Results and analysis are presented in the following five areas: (1) analysis of the genetic structure of Oregon bull trout populations; (2) distribution and habitat use of bull trout and brook trout in streams containing both species; (3) bull trout spawning surveys; (4) summary and analysis of historical juvenile bull trout downstream migrant trap catches in the Grande Ronde basin; and (5) food habits and feeding behavior of bull trout alone and in sympatry with brook trout.

  18. Relative sensitivity of bull trout (Salvelinus confluentus) and rainbow trout (Oncorhynchus mykiss) to acute copper toxicity.

    PubMed

    Hansen, James A; Lipton, Josh; Welsh, Paul G

    2002-03-01

    Bull trout (Salvelinus confluentus) were recently listed as threatened in the United States under the federal Endangered Species Act. Past and present habitat for this species includes waterways contaminated with heavy metals released from mining activities. Because the sensitivity of this species to copper was previously unknown, we conducted acute copper toxicity tests with bull and rainbow trout (Oncorhynchus mykiss) in side-by-side comparison tests. Bioassays were conducted using water at two temperatures (8 degrees C and 16 degrees C) and two hardness levels (100 and 220 mg/L as CaCO3). At a water hardness of 100 mg/L, both species were less sensitive to copper when tested at 16 degrees C compared to 8 degrees C. The two species had similar sensitivity to copper in 100-mg/ L hardness water, but bull trout were 2.5 to 4 times less sensitive than rainbow trout in 220-mg/L hardness water. However, when our results were viewed in the context of the broader literature on rainbow trout sensitivity to copper, the sensitivities of the two species appeared similar. This suggests that adoption of toxicity thresholds that are protective of rainbow trout would be protective of bull trout; however, an additional safety factor may be warranted because of the additional level of protection necessary for this federally threatened species.

  19. Multiscale hydrogeomorphic influences on bull trout (Salvelinus confluentus) spawning habitat

    USGS Publications Warehouse

    Bean, Jared R; Wilcox, Andrew C.; Woessner, William W.; Muhlfeld, Clint C.

    2015-01-01

    We investigated multiscale hydrogeomorphic influences on the distribution and abundance of bull trout (Salvelinus confluentus) spawning in snowmelt-dominated streams of the upper Flathead River basin, northwestern Montana. Within our study reaches, bull trout tended to spawn in the finest available gravel substrates. Analysis of the mobility of these substrates, based on one-dimensional hydraulic modeling and calculation of dimensionless shear stresses, indicated that bed materials in spawning reaches would be mobilized at moderate (i.e., 2-year recurrence interval) high-flow conditions, although the asynchronous timing of the fall–winter egg incubation period and typical late spring – early summer snowmelt high flows in our study area may limit susceptibility to redd scour under current hydrologic regimes. Redd occurrence also tended to be associated with concave-up bedforms (pool tailouts) with downwelling intragravel flows. Streambed temperatures tracked stream water diurnal temperature cycles to a depth of at least 25 cm, averaging 6.1–8.1 °C in different study reaches during the spawning period. Ground water provided thermal moderation of stream water for several high-density spawning reaches. Bull trout redds were more frequent in unconfined alluvial valley reaches (8.5 versus 5.0 redds·km−1 in confined valley reaches), which were strongly influenced by hyporheic and groundwater – stream water exchange. A considerable proportion of redds were patchily distributed in confined valley reaches, however, emphasizing the influence of local physical conditions in supporting bull trout spawning habitat. Moreover, narrowing or “bounding” of these alluvial valley segments did not appear to be important. Our results suggest that geomorphic, thermal, and hydrological factors influence bull trout spawning occurrence at multiple spatial scales.

  20. Monitor and Protect Wigwam River Bull Trout for Koocanusa Reservoir; White River Bull Trout Enumeration Project Summary, Progress Report 2003.

    SciTech Connect

    Cope, R.

    2004-02-01

    This report summarizes the first year of a three-year bull trout (Salvelinus confluentus) enumeration project on the White River and is a co-operative initiative of the British Columbia Ministry of Water, Land, and Air Protection and Bonneville Power Administration. The White River has been identified as an important bull trout spawning tributary of the upper Kootenay River in southeastern British Columbia. The objective was to collect information on the returning adult spawning population to the White River through the use of a fish fence and traps, and to conduct redd surveys at the conclusion of spawning to provide an index of spawning escapement and distribution. The fence was installed on September 9th, 2003 and was operated continuously (i.e. no high-water or breaching events) until the fence was removed on October 9th, 2003. Estimation of the spawning population of White River bull trout was incomplete. This was due to a larger and more protracted out-migration than expected. As a result, the bull trout spawning population of the White River was estimated to be somewhere above 899 fish. In comparison, this represents approximately one third the population estimate of the 2003 Wigwam River bull trout spawning population. Based on redd index data, the number of bull trout per redd was over twice that of the Wigwam River or Skookumchuck Creek. This was expected as the index sites on the Wigwam River and Skookumchuck Creek cover the majority of the spawning area. This is not true on the White River. From previous redd counts, it is known that there are approximately twice as many redds in Blackfoot Creek as there are in the index site. Additionally, given the large size of the White River watershed and in particular, the large number of tributaries, there is a high likelihood that important bull trout spawning areas remain unidentified. Both floy tag and radio-telemetry data for the White River bull trout have identified extensive life history migrations

  1. Upstream movement of residual hatchery steelhead into areas containing bull trout and cutthroat trout.

    SciTech Connect

    McMichael, Geoffrey A. ); Pearsons, Todd N.

    2000-11-01

    Hatchery-reared steelhead Oncorhynchus mykiss that do not emigrate as smolts shortly after release may negatively impact wild fish communities through ecological interactions. We used systematic, stratified snorkeling surveys to document the relative abundance of wild rainbow trout O. mykiss, bull trout Salvelinus confluentus, and westslope cutthroat trout O. clarki lewisi as well as the upstream limit of residual hatchery steelhead (hatchery-reared steelhead that had failed to emigrate before June 1). Our objective was to determine whether residual hatchery steelhead had migrated upstream from their release point into an area containing a threatened population of bull trout and cutthroat trout. Hatchery steelhead made up a larger portion of the salmonid community in the sites near their release location (mean= 52.5%, range= 29-79%), and constituted a lower proportion (mean= 4.8%, range= 0-14%) of the salmonid community as distance upstream of the release location increased. However, residual hatchery steelhead had migrated over 12 km upstream into an area containing a threatened stock of bull trout and westslope cutthroat trout O. clarki lewisi.

  2. Temporary Restoration of Bull Trout Passage at Albeni Falls Dam

    SciTech Connect

    Paluch, Mark; Scholz, Allan; McLellan, Holly; Olson, Jason

    2009-07-13

    This study was designed to monitor movements of bull trout that were provided passage above Albeni Falls Dam, Pend Oreille River. Electrofishing and angling were used to collect bull trout below the dam. Tissue samples were collected from each bull trout and sent to the U. S. Fish and Wildlife Service Abernathy Fish Technology Center Conservation Genetics Lab, Washington. The DNA extracted from tissue samples were compared to a catalog of bull trout population DNA from the Priest River drainage, Lake Pend Oreille tributaries, and the Clark Fork drainage to determine the most probable tributary of origin. A combined acoustic radio or radio tag was implanted in each fish prior to being transported and released above the dam. Bull trout relocated above the dam were able to volitionally migrate into their natal tributary, drop back downstream, or migrate upstream to the next dam. A combination of stationary radio receiving stations and tracking via aircraft, boat, and vehicle were used to monitor the movement of tagged fish to determine if the spawning tributary it selected matched the tributary assigned from the genetic analysis. Seven bull trout were captured during electrofishing surveys in 2008. Of these seven, four were tagged and relocated above the dam. Two were tagged and left below the dam as part of a study monitoring movements below the dam. One was immature and too small at the time of capture to implant a tracking tag. All four fish released above the dam passed by stationary receivers stations leading into Lake Pend Oreille and no fish dropped back below the dam. One of the radio tags was recovered in the tributary corresponding with the results of the genetic test. Another fish was located in the vicinity of its assigned tributary, which was impassable due to low water discharge at its mouth. Two fish have not been located since entering the lake. Of these fish, one was immature and not expected to enter its natal tributary in the fall of 2008. The other

  3. Lake trout (Salvelinus namaycush) suppression for bull trout (Salvelinus confluentus) recovery in Flathead Lake, Montana, North America

    USGS Publications Warehouse

    Hansen, Michael J.; Hansen, Barry S; Beauchamp, David A.

    2016-01-01

    Non-native lake trout Salvelinus namaycush displaced native bull trout Salvelinus confluentus in Flathead Lake, Montana, USA, after 1984, when Mysis diluviana became abundant following its introduction in upstream lakes in 1968–1976. We developed a simulation model to determine the fishing mortality rate on lake trout that would enable bull trout recovery. Model simulations indicated that suppression of adult lake trout by 75% from current abundance would reduce predation on bull trout by 90%. Current removals of lake trout through incentivized fishing contests has not been sufficient to suppress lake trout abundance estimated by mark-recapture or indexed by stratified-random gill netting. In contrast, size structure, body condition, mortality, and maturity are changing consistent with a density-dependent reduction in lake trout abundance. Population modeling indicated total fishing effort would need to increase 3-fold to reduce adult lake trout population density by 75%. We conclude that increased fishing effort would suppress lake trout population density and predation on juvenile bull trout, and thereby enable higher abundance of adult bull trout in Flathead Lake and its tributaries.

  4. Summer microhabitat use of fluvial bull trout in Eastern Oregon streams

    USGS Publications Warehouse

    Al-Chokhachy, R.; Budy, P.

    2007-01-01

    The management and recovery of populations of bull trout Salvelinus confluentus requires a comprehensive understanding of habitat use across different systems, life stages, and life history forms. To address these needs, we collected microhabitat use and availability data in three fluvial populations of bull trout in eastern Oregon. We evaluated diel differences in microhabitat use, the consistency of microhabitat use across systems and size-classes based on preference, and our ability to predict bull trout microhabitat use. Diel comparisons suggested bull trout continue to use deeper microhabitats with cover but shift into significantly slower habitats during nighttime periods; however, we observed no discrete differences in substrate use patterns across diel periods. Across life stages, we found that both juvenile and adult bull trout used slow-velocity microhabitats with cover, but the use of specific types varied. Both logistic regression and habitat preference analyses suggested that adult bull trout used deeper habitats than juveniles. Habitat preference analyses suggested that bull trout habitat use was consistent across all three systems, as chi-square tests rejected the null hypotheses that microhabitats were used in proportion to those available (P < 0.0001). Validation analyses indicated that the logistic regression models (juvenile and adult) were effective at predicting bull trout absence across all tests (specificity values = 100%); however, our ability to accurately predict bull trout absence was limited (sensitivity values = 0% across all tests). Our results highlight the limitations of the models used to predict microhabitat use for fish species like bull trout, which occur at naturally low densities. However, our results also demonstrate that bull trout microhabitat use patterns are generally consistent across systems, a pattern that parallels observations at both similar and larger scales and across life history forms. Thus, our results, in

  5. Distribution and Movement of Bull Trout in the Upper Jarbidge River Watershed, Nevada

    USGS Publications Warehouse

    Allen, M. Brady; Connolly, Patrick J.; Mesa, Matthew G.; Charrier, Jodi; Dixon, Chris

    2010-01-01

    In 2006 and 2007, we surveyed the occurrence of bull trout (Salvelinus confluentus), the relative distributions of bull trout and redband trout (Oncorhynchus mykiss), and stream habitat conditions in the East and West Forks of the Jarbidge River in northeastern Nevada and southern Idaho. We installed passive integrated transponder (PIT) tag interrogation systems at strategic locations within the watershed, and PIT-tagged bull trout were monitored to evaluate individual fish growth, movement, and the connectivity of bull trout between streams. Robust bull trout populations were found in the upper portions of the East Fork Jarbidge River, the West Fork Jarbidge River, and in the Pine, Jack, Dave, and Fall Creeks. Small numbers of bull trout also were found in Slide and Cougar Creeks. Bull trout were numerically dominant in the upper portions of the East Fork Jarbidge River, and in Fall, Dave, Jack, and Pine Creeks, whereas redband trout were numerically dominant throughout the rest of the watershed. The relative abundance of bull trout was notably higher at altitudes above 2,100 m. This study was successful in documenting bull trout population connectivity within the West Fork Jarbidge River, particularly between West Fork Jarbidge River and Pine Creek. Downstream movement of bull trout to the confluence of the East Fork and West Fork Jarbidge River both from Jack Creek (rkm 16.6) in the West Fork Jarbidge River and from Dave Creek (rkm 7.5) in the East Fork Jarbidge River was detected. Although bull trout exhibited some downstream movement during the spring and summer, much of their emigration occurred in the autumn, concurrent with decreasing water temperatures and slightly increasing flows. The bull trout that emigrated were mostly age-2 or older, but some age-1 fish also emigrated. Upstream movement by bull trout was detected less than downstream movement. The overall mean annual growth rate of bull trout in the East Fork and West Fork Jarbidge River was 36 mm

  6. Bull Trout Population Assessment in the Columbia River Gorge : Annual Report 2000.

    SciTech Connect

    Byrne, Jim; McPeak, Ron

    2001-02-01

    We summarized existing knowledge regarding the known distribution of bull trout (Salvelinus confluentus) across four sub-basins in the Columbia River Gorge in Washington. The Wind River, Little White Salmon River, White Salmon River, and the Klickitat River sub-basins were analyzed. Cold water is essential to the survival, spawning, and rearing of bull trout. We analyzed existing temperature data, installed Onset temperature loggers in the areas of the four sub-basins where data was not available, and determined that mean daily water temperatures were <15 C and appropriate for spawning and rearing of bull trout. We snorkel surveyed more than 74 km (46.25 mi.) of rivers and streams in the four sub-basins (13.8 km at night and 60.2 km during the day) and found that night snorkeling was superior to day snorkeling for locating bull trout. Surveys incorporated the Draft Interim Protocol for Determining Bull Trout Presence (Peterson et al. In Press). However, due to access and safety issues, we were unable to randomly select sample sites nor use block nets as recommended. Additionally, we also implemented the Bull Trout/Dolly Varden sampling methodology described in Bonar et al. (1997). No bull trout were found in the Wind River, Little White Salmon, or White Salmon River sub-basins. We found bull trout in the West Fork Klickitat drainage of the Klickitat River Sub-basin. Bull trout averaged 6.7 fish/100m{sup 2} in Trappers Creek, 2.6 fish/100m{sup 2} on Clearwater Creek, and 0.4 fish/100m{sup 2} in Little Muddy Creek. Bull trout was the only species of salmonid encountered in Trappers Creek and dominated in Clearwater Creek. Little Muddy Creek was the only creek where bull trout and introduced brook trout occurred together. We found bull trout only at night and typically in low flow regimes. A single fish, believed to be a bull trout x brook trout hybrid, was observed in the Little Muddy Creek. Additional surveys are needed in the West Fork Klickitat and mainstem

  7. Thermal regimes, nonnative trout, and their influences on native Bull Trout in the Upper Klamath River Basin, Oregon

    USGS Publications Warehouse

    Benjamin, Joseph R.; Heltzel, Jeannie; Dunham, Jason; Heck, Michael; Banish, Nolan P.

    2016-01-01

    The occurrence of fish species may be strongly influenced by a stream’s thermal regime (magnitude, frequency, variation, and timing). For instance, magnitude and frequency provide information about sublethal temperatures, variability in temperature can affect behavioral thermoregulation and bioenergetics, and timing of thermal events may cue life history events, such as spawning and migration. We explored the relationship between thermal regimes and the occurrences of native Bull Trout Salvelinus confluentus and nonnative Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta across 87 sites in the upper Klamath River basin, Oregon. Our objectives were to associate descriptors of the thermal regime with trout occurrence, predict the probability of Bull Trout occurrence, and estimate upper thermal tolerances of the trout species. We found that each species was associated with a different suite of thermal regime descriptors. Bull Trout were present at sites that were cooler, had fewer high-temperature events, had less variability, and took longer to warm. Brook Trout were also observed at cooler sites with fewer high-temperature events, but the sites were more variable and Brook Trout occurrence was not associated with a timing descriptor. In contrast, Brown Trout were present at sites that were warmer and reached higher temperatures faster, but they were not associated with frequency or variability descriptors. Among the descriptors considered, magnitude (specifically June degree-days) was the most important in predicting the probability of Bull Trout occurrence, and model predictions were strengthened by including Brook Trout occurrence. Last, all three trout species exhibited contrasting patterns of tolerating longer exposures to lower temperatures. Tolerance limits for Bull Trout were lower than those for Brook Trout and Brown Trout, with contrasts especially evident for thermal maxima. Our results confirm the value of exploring a suite of thermal

  8. Adaptive Management of Bull Trout Populations in the Lemhi Basin

    USGS Publications Warehouse

    Peterson, James T.; Tyre, Andrew J.; Converse, Sarah J.; Bogich, Tiffany L.; Miller, Damien; Post van der Burg, Max; Thomas, Carmen; Thompson, Ralph J.; Wood, Jeri; Brewer, Donna; Runge, Michael C.

    2011-01-01

    The bull trout Salvelinus confluentus, a stream-living salmonid distributed in drainages of the northwestern United States, is listed as threatened under the Endangered Species Act because of rangewide declines. One proposed recovery action is the reconnection of tributaries in the Lemhi Basin. Past water use policies in this core area disconnected headwater spawning sites from downstream habitat and have led to the loss of migratory life history forms. We developed an adaptive management framework to analyze which types of streams should be prioritized for reconnection under a proposed Habitat Conservation Plan. We developed a Stochastic Dynamic Program that identified optimal policies over time under four different assumptions about the nature of the migratory behavior and the effects of brook trout Salvelinus fontinalis on subpopulations of bull trout. In general, given the current state of the system and the uncertainties about the dynamics, the optimal policy would be to connect streams that are currently occupied by bull trout. We also estimated the value of information as the difference between absolute certainty about which of our four assumptions were correct, and a model averaged optimization assuming no knowledge. Overall there is little to be gained by learning about the dynamics of the system in its current state, although in other parts of the state space reducing uncertainties about the system would be very valuable. We also conducted a sensitivity analysis; the optimal decision at the current state does not change even when parameter values are changed up to 75% of the baseline values. Overall, the exercise demonstrates that it is possible to apply adaptive management principles to threatened and endangered species, but logistical and data availability constraints make detailed analyses difficult.

  9. Monitor and Protect Wigwam River Bull Trout for Koocanusa Reservoir : Summary of the Skookumchuck Creek Bull Trout Enumeration Project Final Report 2000-2002.

    SciTech Connect

    Baxter, Jeremy; Baxter, James S.

    2002-12-01

    This report summarizes the third and final year of a bull trout (Salvelinus confluentus) enumeration project on Skookumchuck Creek in southeastern British Columbia. The fence and traps were operated from September 6th to October 11th 2002 in order to enumerate post-spawning bull trout. During the study period a total of 309 bull trout were captured at the fence. In total, 16 fish of undetermined sex, 114 males and 179 females were processed at the fence. Length and weight data, as well as recapture information, were collected for these fish. An additional 41 bull trout were enumerated upstream of the fence by snorkeling prior to fence removal. Coupled with the fence count, the total bull trout enumerated during the project was 350 individuals. Several fish that were tagged in the lower Bull River were recaptured in 2002, as were repeat and alternate year spawners previously enumerated in past years at the fence. A total of 149 bull trout redds were enumerated on the ground in 2002, of which 143 were in the 3.0 km index section (river km 27.5-30.5) that has been surveyed over the past six years. The results of the three year project are summarized, and population characteristics are discussed.

  10. Monitor and Protect Wigwam River Bull Trout for Koocanusa Reservoir : Summary of the Skookumchuck Creek Bull Trout Enumeration Project, Annual Report 2001.

    SciTech Connect

    Baxter, James S.; Baxter, Jeremy

    2002-03-01

    This report summarizes the second year of a bull trout (Salvelinus confluentus) enumeration project on Skookumchuck Creek in southeastern British Columbia. An enumeration fence and traps were installed on the creek from September 6th to October 12th 2001 to enable the capture of post-spawning bull trout emigrating out of the watershed. During the study period, a total of 273 bull trout were sampled through the enumeration fence. Length and weight were determined for all bull trout captured. In total, 39 fish of undetermined sex, 61 males and 173 females were processed through the fence. An additional 19 bull trout were observed on a snorkel survey prior to the fence being removed on October 12th. Coupled with the fence count, the total bull trout enumerated during this project was 292 fish. Several other species of fish were captured at the enumeration fence including westslope cutthroat trout (Oncorhynchus clarki lewisi), Rocky Mountain whitefish (Prosopium williamsoni), and kokanee (O. nerka). A total of 143 bull trout redds were enumerated on the ground in two different locations (river km 27.5-30.5, and km 24.0-25.5) on October 3rd. The majority of redds (n=132) were observed in the 3.0 km index section (river km 27.5-30.5) that has been surveyed over the past five years. The additional 11 redds were observed in a 1.5 km section (river km 24.0-25.5). Summary plots of water temperature for Bradford Creek, Sandown Creek, Buhl Creek, and Skookumchuck Creek at three locations suggested that water temperatures were within the temperature range preferred by bull trout for spawning, egg incubation, and rearing.

  11. Spawning migration of lacustrine-adfluvial bull trout in a natural area

    USGS Publications Warehouse

    Brenkman, Samuel J.; Larson, Gary L.; Gresswell, Robert E.

    2001-01-01

    We investigated the spawning migration of lacustrine-adfluvial bull trout Salvelinus confluentus in the North Fork Skokomish River in Olympic National Park (Washington State) during 1996. Day-snorkeling and electrofishing were conducted to determine timing and duration of the migration and the distribution and abundance of bull trout. The primary spawning migration began in early October and was waning by December. Bull trout migrated 6 km or less up the river from Lake Cushman. Increased river discharge and decreased water temperature appeared to be the primary environmental variables corresponding to the initiation of the migration. Mean length of migratory bull trout increased from June to December. Comparisons with other lacustrine-adfluvial bull trout populations in Oregon, Montana, Idaho, and British Columbia suggested that these populations exhibit specific migratory strategies related to local environmental conditions.

  12. Monitor and Protect Wigwam River Bull Trout for Koocanusa Reservoir : Summary of the Skookumchuck Creek Bull Trout Enumeration Project, Annual Report 2000.

    SciTech Connect

    Baxter, James S.; Baxter, Jeremy

    2001-02-01

    An enumeration fence and traps were installed on Skookumchuck Creek from September 7 th to October 16 th to enable the capture of post-spawning bull trout emigrating out of the watershed. During the study period, a total of 252 bull trout were sampled through the enumeration fence. Length, weight, and sex were determined for all but one of the 252 bull trout captured. In total, one fish of undetermined sex, 63 males and 188 females were processed through the fence. A total of 67 bull trout were observed on a snorkel survey prior to the fence being removed on October 16 th . Coupled with the fence count, the total bull trout count during this project was 319 fish. Several other species of fish were captured at the enumeration fence including westslope cutthroat trout, Rocky Mountain whitefish, kokanee, sucker, and Eastern brook trout. Redds were observed during ground surveys in three different locations (river km 27.5- 28.5, km 29-30, and km 24-25). The largest concentration of redds were noted in the upper two sections which have served as the index sections over the past four years. A total of 197 bull trout redds were enumerated on the ground on October 4 th . The majority of redds (n=189) were observed in the 3.0 km index section (river km 27.5-30.5) that has been surveyed over the past four years. The additional 8 redds were observed in a 1.5 km section (river km 24.0-25.5). Summary plots of water temperature for Bradford Creek, Sandown Creek, Skookumchuck Creek at km 39.5, and Skookumchuck Creek at the fence site suggested that water temperatures were within the range preferred by bull trout for spawning, egg incubation, and rearing.

  13. Wigwam River Juvenile Bull Trout and Fish Habitat Monitoring Program : 2000 Data Report.

    SciTech Connect

    Cope, R.S.; Morris, K.J.

    2001-03-01

    The Wigwam River bull trout (Salvelinus confluentus) and fish habitat monitoring program is a trans-boundary initiative implemented by the British Columbia Ministry of Environment, Lands and Parks (MOE), in cooperation with Bonneville Power Administration (BPA). The Wigwam River is an important fisheries stream located in southeastern British Columbia that supports healthy populations of both bull trout and Westslope cutthroat trout (Figure 1.1). This river has been characterized as the single most important bull trout spawning stream in the Kootenay Region (Baxter and Westover 2000, Cope 1998). In addition, the Wigwam River supports some of the largest Westslope cutthroat trout (Oncorhynchus clarki lewisi) in the Kootenay Region. These fish are highly sought after by anglers (Westover 1999a, 1999b). Bull trout populations have declined in many areas of their range within Montana and throughout the northwest including British Columbia. Bull trout were blue listed as vulnerable in British Columbia by the B.C. Conservation Data Center (Cannings 1993) and although there are many healthy populations of bull trout in the East Kootenays they remain a species of special concern. Bull trout in the United States portion of the Columbia River were listed as threatened in 1998 under the Endangered Species Act by the U.S. Fish and Wildlife Service. The upper Kootenay River is within the Kootenai sub-basin of the Mountain Columbia Province, one of the eleven Eco-provinces that make up the Columbia River Basin. MOE applied for and received funding from BPA to assess and monitor the status of wild, native stocks of bull trout in tributaries to Lake Koocanusa (Libby Reservoir) and the upper Kootenay River. This task is one of many that was undertaken to ''Monitor and Protect Bull Trout for Koocanusa Reservoir'' (BPA Project Number 2000-04-00).

  14. Wigwam River Juvenile Bull Trout and Fish Habitat Monitoring Program : 2002 Data Report.

    SciTech Connect

    Cope, R.S.

    2003-03-01

    The Wigwam River bull trout (Salvelinus confluentus) and fish habitat monitoring program is a trans-boundary initiative implemented by the British Columbia Ministry of Water, Land, and Air Protection (MWLAP), in cooperation with Bonneville Power Administration (BPA). The Wigwam River is an important fisheries stream located in southeastern British Columbia that supports healthy populations of both bull trout and Westslope cutthroat trout (Figure 1). This river has been characterized as the single most important bull trout spawning stream in the Kootenay Region (Baxter and Westover 2000, Cope 1998). In addition, the Wigwam River supports some of the largest Westslope cutthroat trout (Oncorhynchus clarki lewisi) in the Kootenay Region. These fish are highly sought after by anglers (Westover 1999a, 1999b). Bull trout populations have declined in many areas of their range within Montana and throughout the northwest including British Columbia. Bull trout were blue listed as vulnerable in British Columbia by the B.C. Conservation Data Center (Cannings 1993) and although there are many healthy populations of bull trout in the East Kootenay they remain a species of special concern. Bull trout in the United States portion of the Columbia River were listed as threatened in 1998 under the Endangered Species Act by the U.S. Fish and Wildlife Service. The upper Kootenay River is within the Kootenai sub-basin of the Mountain Columbia Province, one of the eleven Eco-provinces that make up the Columbia River Basin. MWLAP applied for and received funding from BPA to assess and monitor the status of wild, native stocks of bull trout in tributaries to Lake Koocanusa (Libby Reservoir) and the upper Kootenay River. This task is one of many that were undertaken to ''Monitor and Protect Bull Trout for Koocanusa Reservoir'' (BPA Project Number 2000-04-00).

  15. Bull Trout Distribution and Abundance in the Waters on and Bordering the Warm Springs Indian Reservation, 2000 Annual Report.

    SciTech Connect

    Brun, Christopher

    2000-01-01

    The range of bull trout (Salvelinus confluentus) in the Deschutes River basin has decreased from historic levels due to many factors including dam construction, habitat degradation, brook trout introduction and eradication efforts. While the bull trout population appears to be stable in the Metolius River-Lake Billy Chinook system they have been largely extirpated from the upper Deschutes River (Buchanan et al. 1997). Little was known about bull trout in the lower Deschutes basin until BPA funded project No.9405400 began during 1998. In this progress report we describe the findings from the third year (2000) of the multi-year study aimed at determining the life history, genetics, habitat needs and limiting factors of bull trout in the lower Deschutes subbasin. Juvenile bull trout and brook trout (Salvelinus fontinalis) relative abundance was assessed in the Warm Springs River and Shitike Creek by night snorkeling. In the Warm Springs R. juvenile bull trout were slightly more numerous than brook trout, however, both were found in low densities. Relative densities of both species declined from 1999 observations. Juvenile bull trout vastly out numbered brook trout in Shitike Cr. Relative densities of juvenile bull trout increased while brook trout abundance was similar to 1999 observations in eight index reaches. The utility of using index reaches to monitor trends in juvenile bull trout and brook trout relative abundance was assessed in the Warm Springs R. for the second year. Mean relative densities of both species, within the index reaches was slightly higher than what was observed in a 2.4 km control reach. Mill Creek was surveyed for the presence of juvenile bull trout. The American Fisheries Society ''Interim protocol for determining bull trout presence'' methodology was field tested. No bull trout were found in the 2 km survey area.

  16. Sprint swimming performance of wild bull trout (Salvelinus confluentus)

    USGS Publications Warehouse

    Mesa, M.G.; Phelps, J.; Weiland, L.K.

    2008-01-01

    We conducted laboratory experiments to determine the sprint swimming performance of wild juvenile and adult bull trout Salvelinus confluentus. Sprint swimming speeds were estimated using high-speed digital video analysis. Thirty two bull trout were tested in sizes ranging from about 10 to 31 cm. Of these, 14 fish showed at least one motivated, vigorous sprint. When plotted as a function of time, velocity of fish increased rapidly with the relation linear or slightly curvilinear. Their maximum velocity, or Vmax, ranged from 1.3 to 2.3 m/s, was usually achieved within 0.8 to 1.0 s, and was independent of fish size. Distances covered during these sprints ranged from 1.4 to 2.4 m. Our estimates of the sprint swimming performance are the first reported for this species and may be useful for producing or modifying fish passage structures that allow safe and effective passage of fish without overly exhausting them. ?? 2008 by the Northwest Scientific Association. All rights reserved.

  17. Proposed standard-weight (W(s)) equations for kokanee, golden trout and bull trout

    USGS Publications Warehouse

    Hyatt, M.H.; Hubert, W.A.

    2000-01-01

    We developed standard-weight (W(s)) equations for kokanee (lacustrine Oncorhynchus nerka), golden trout (O. aguabonita), and bull trout (Salvelinus confluentus) using the regression-line-percentile technique. The W(s) equation for kokanee of 120-550 mm TL is log10 W(s) = -5.062 + 3.033 log10 TL, when W(s) is in grams and TL is total length in millimeters; the English-unit equivalent is log10 W(s) = -3.458 + 3.033 log10 TL, when W(s) is in pounds and TL is total length in inches. The W(s) equation for golden trout of 120-530 mm TL is log10 W(s) = -5.088 + 3.041 log10 TL, with the English-unit equivalent being log10 W(s) = -3.473 + 3.041 log10 TL. The W(s) equation for bull trout of 120-850 mm TL is log10 W(s) = -5.327 + 3.115 log10 TL, with the English-unit equivalent being log10 W(s) = -3.608 + 3.115 log10 TL.

  18. Temporary Restoration of Bull Trout Passage at Albeni Falls Dam, 2008 Progress Report.

    SciTech Connect

    Bellgraph, Brian J.

    2009-03-31

    The goal of this project is to provide temporary upstream passage of bull trout around Albeni Falls Dam on the Pend Oreille River, Idaho. Our specific objectives are to capture fish downstream of Albeni Falls Dam, tag them with combination acoustic and radio transmitters, release them upstream of Albeni Falls Dam, and determine if genetic information on tagged fish can be used to accurately establish where fish are located during the spawning season. In 2007, radio receiving stations were installed at several locations throughout the Pend Oreille River watershed to detect movements of adult bull trout; however, no bull trout were tagged during that year. In 2008, four bull trout were captured downstream of Albeni Falls Dam, implanted with transmitters, and released upstream of the dam at Priest River, Idaho. The most-likely natal tributaries of bull trout assigned using genetic analyses were Grouse Creek (N = 2); a tributary of the Pack River, Lightning Creek (N = 1); and Rattle Creek (N = 1), a tributary of Lightning Creek. All four bull trout migrated upstream from the release site in Priest River, Idaho, were detected at monitoring stations near Dover, Idaho, and were presumed to reside in Lake Pend Oreille from spring until fall 2008. The transmitter of one bull trout with a genetic assignment to Grouse Creek was found in Grouse Creek in October 2008; however, the fish was not found. The bull trout assigned to Rattle Creek was detected in the Clark Fork River downstream from Cabinet Gorge Dam (approximately 13 km from the mouth of Lightning Creek) in September but was not detected entering Lightning Creek. The remaining two bull trout were not detected in 2008 after detection at the Dover receiving stations. This report details the progress by work element in the 2008 statement of work, including data analyses of fish movements, and expands on the information reported in the quarterly Pisces status reports.

  19. Bull Trout Life History, Genetics, Habitat Needs, and Limiting Fact in Central and Northeast Oregon. Annual Report 1999.

    SciTech Connect

    Hemmingsen, Alan R.; Gunckel, Stephanie L.; Howell, Philip J.

    2001-08-01

    This section describes work accomplished in 1999 that continued to address two objectives of this project. These objectives are (1) determine the distribution of juvenile and adult bull trout Salvelinus confluentus and habitats associated with that distribution, and (2) determine fluvial and resident bull trout life history patterns. Completion of these objectives is intended through studies of bull trout in the Grande Ronde, Walla Walla, and John Day basins. These basins were selected because they provide a variety of habitats, from relatively degraded to pristine, and bull trout populations were thought to vary from relatively depressed to robust. In all three basins we used radio telemetry to determine the seasonal movements of bull trout. In the John Day and Walla Walla basins we also used traps to capture migrant bull trout. With these traps, we intended to determine the timing of bull trout movements both upstream and downstream, determine the relative abundance, size and age of migrant fish, and capture bull trout to be implanted with radio transmitters. In the John Day basin, we captured adult and juvenile bull trout from the upper John Day River and its tributaries, Call Creek, Reynolds Creek, and Roberts Creek. In the Walla Walla basin, we captured adult and juvenile bull trout from Mill Creek.

  20. Investigations of Bull Trout (Salvelinus Confluentus), Steelhead Trout (Oncorhynchus Mykiss), and Spring Chinook Salmon (O. Tshawytscha) Interactions in Southeast Washington Streams : 1991 Annual Report.

    SciTech Connect

    Martin, Steven W.

    1992-07-01

    Bull trout (Salvelinus confluentus) are native to many tributaries of the Snake River in southeast Washington. The Washington Department of Wildlife (WDW) and the American Fisheries Society (AFS) have identified bull trout as a species of special concern which means that they may become threatened or endangered by relatively, minor disturbances to their habitat. Steelhead trout/rainbow trout (Oncorhynchus mykiss) and spring chinook salmon (O.tshawytscha) are also native to several tributaries of the Snake river in southeast Washington. These species of migratory fishes are depressed, partially due to the construction of several dams on the lower Snake river. In response to decreased run size, large hatchery program were initiated to produce juvenile steelhead and salmon to supplement repressed tributary stocks, a practice known as supplementation. There is a concern that supplementing streams with artificially high numbers of steelhead and salmon may have an impact on resident bull trout in these streams. Historically, these three species of fish existed together in large numbers, however, the amount of high-quality habitat necessary for reproduction and rearing has been severely reduced in recent years, as compared to historic amounts. The findings of the first year of a two year study aimed at identifying species interactions in southeast Washington streams are presented in this report. Data was collected to assess population dynamics; habitat utilization and preference, feeding habits, fish movement and migration, age, condition, growth, and the spawning requirements of bull trout in each of four streams. A comparison of the indices was then made between the study streams to determine if bull trout differ in the presence of the putative competitor species. Bull trout populations were highest in the Tucannon River (supplemented stream), followed by Mill Creek (unsupplemented stream). Young of the year bull trout utilized riffle and cascade habitat the most in all

  1. Development and evaluation of a bioenergetics model for bull trout

    USGS Publications Warehouse

    Mesa, Matthew G.; Welland, Lisa K.; Christiansen, Helena E.; Sauter, Sally T.; Beauchamp, David A.

    2013-01-01

    We conducted laboratory experiments to parameterize a bioenergetics model for wild Bull Trout Salvelinus confluentus, estimating the effects of body mass (12–1,117 g) and temperature (3–20°C) on maximum consumption (C max) and standard metabolic rates. The temperature associated with the highest C max was 16°C, and C max showed the characteristic dome-shaped temperature-dependent response. Mass-dependent values of C max (N = 28) at 16°C ranged from 0.03 to 0.13 g·g−1·d−1. The standard metabolic rates of fish (N = 110) ranged from 0.0005 to 0.003 g·O2·g−1·d−1 and increased with increasing temperature but declined with increasing body mass. In two separate evaluation experiments, which were conducted at only one ration level (40% of estimated C max), the model predicted final weights that were, on average, within 1.2 ± 2.5% (mean ± SD) of observed values for fish ranging from 119 to 573 g and within 3.5 ± 4.9% of values for 31–65 g fish. Model-predicted consumption was within 5.5 ± 10.9% of observed values for larger fish and within 12.4 ± 16.0% for smaller fish. Our model should be useful to those dealing with issues currently faced by Bull Trout, such as climate change or alterations in prey availability.

  2. Bioenergetic evaluation of diel vertical migration by bull trout (Salvelinus confluentus) in a thermally stratified reservoir

    USGS Publications Warehouse

    Eckmann, Madeleine; Dunham, Jason; Connor, Edward J.; Welch, Carmen A.

    2016-01-01

    Many species living in deeper lentic ecosystems exhibit daily movements that cycle through the water column, generally referred to as diel vertical migration (DVM). In this study, we applied bioenergetics modelling to evaluate growth as a hypothesis to explain DVM by bull trout (Salvelinus confluentus) in a thermally stratified reservoir (Ross Lake, WA, USA) during the peak of thermal stratification in July and August. Bioenergetics model parameters were derived from observed vertical distributions of temperature, prey and bull trout. Field sampling confirmed that bull trout prey almost exclusively on recently introduced redside shiner (Richardsonius balteatus). Model predictions revealed that deeper (>25 m) DVMs commonly exhibited by bull trout during peak thermal stratification cannot be explained by maximising growth. Survival, another common explanation for DVM, may have influenced bull trout depth use, but observations suggest there may be additional drivers of DVM. We propose these deeper summertime excursions may be partly explained by an alternative hypothesis: the importance of colder water for gametogenesis. In Ross Lake, reliance of bull trout on warm water prey (redside shiner) for consumption and growth poses a potential trade-off with the need for colder water for gametogenesis.

  3. Relative sensitivity of bull trout (Salvelinus confluentus) and rainbow trout (Oncorhynchus mykiss) to acute exposures of cadmium and zinc.

    PubMed

    Hansen, James A; Welsh, Paul G; Lipton, Josh; Cacela, Dave; Dailey, Anne D

    2002-01-01

    Bull trout (Salvelinus confluentus) were recently listed as threatened in the United States under the federal Endangered Species Act. Present and historical habitat of this species includes waterways that have been impacted by metals released from mining and mineral processing activities. We conducted paired bioassays with bull trout and rainbow trout (Oncorhynchus mykiss) to examine the relative sensitivity of each species to Cd and Zn independently and as a mixture. A total of 15 pairs of acute toxicity bioassays were completed to evaluate the effects of different water hardness (30 or 90 mg/L as CaCO3), pH (6.5 or 7.5), and temperature (8 or 12 degrees C) on Cd and Zn toxicity. For both species, the acute toxicity of both Cd and Zn was greater than previously observed in laboratory studies. Bull trout were about twice as tolerant of Cd and about 50% more tolerant of Zn than were rainbow trout. Higher hardness and lower pH water produced lower toxicity and slower rates of toxicity in both species. Elevated temperature significantly increased the sensitivity of bull trout to Zn but decreased the sensitivity (not significantly) of rainbow trout to Zn. At a hardness of 30 mg/L, the toxicity values (i.e., median lethal concentration; 120-h LC50) for both species were lower than the current U.S. national water quality criteria for protection of aquatic life, indicating that current national criteria may not be protective of sensitive salmonids--including the threatened bull trout--in low calcium waters.

  4. Physical, biotic, and sampling influences on diel habitat use by stream-dwelling bull trout

    USGS Publications Warehouse

    Banish, N.P.; Peterson, J.T.; Thurow, R.F.

    2008-01-01

    We used daytime and nighttime underwater observation to assess microhabitat use by bull trout Salvelinus confluentus (N = 213) in streams of the intermountain western USA during the summers of 2001 and 2002. We recorded fish focal points and measured a set of habitat characteristics as well as habitat availability via line transects. Bull trout were benthic and solitary; most (88%) were observed at night. We developed a conditional logistic regression model to account for the effect of fish movement in response to snorkeling, and we fitted 18 candidate models to evaluate the relative influences of biotic and abiotic factors on habitat use. The candidate models were also fitted with a naive logistic regression (i.e., no movement) to evaluate the effects of movement on inferences of microhabitat use. The most plausible model describing bull trout habitat use was the same for the conditional and nai??ve regressions and included depth, velocity, percent rubble substratum, and the day X depth, body size X depth, and body size X day X depth interactions. The presence of brook trout S. fontinalis and the abundance of conspecifics did not strongly influence microhabitat use by bull trout. The relative rankings of the remaining models differed substantially between the conditional and nai??ve models. Relative to the conditional models, the naive models overestimated the importance of diurnal differences in habitat use and overestimated the use of deepwater habitats, particularly during the day. Both model types suggested that all sizes of bull trout were generally found in deeper, low-velocity habitat at night, whereas small bull trout (70-90 mm total length) were found in shallower habitats during the day. We recommend lhat biologists account for fish movement in response to sampling to avoid biasing modeled habitat use patterns by bull trout. ?? Copyright by the American Fisheries Society 2008.

  5. Factors influencing the distribution of native bull trout and westslope cutthroat trout in western Glacier National Park, Montana

    USGS Publications Warehouse

    D'Angelo, Vincent S.; Muhlfeld, Clint C.

    2013-01-01

    The widespread declines of native bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) populations prompted researchers to investigate factors influencing their distribution and status in western Glacier National Park, Montana. We evaluated the association of a suite of abiotic factors (stream width, elevation, gradient, large woody debris density, pool density, August mean stream temperature, reach surface area) with the occurrence (presence or absence) of bull trout and westslope cutthroat trout in 79 stream reaches in five sub-drainages containing glacial lakes. We modeled the occurrence of each species using logistic regression and evaluated competing models using an information theoretic approach. Westslope cutthroat trout were widely distributed (47 of 79 reaches), and there appeared to be no restrictions on their distribution other than physical barriers. Westslope cutthroat trout were most commonly found in relatively warm reaches downstream of lakes and in headwater reaches with large amounts of large woody debris and abundant pools. By contrast, bull trout were infrequently detected (10 of 79 reaches), with 7 of the 10 (70%) detections in sub-drainages that have not been compromised by non-native lake trout (S. namaycush). Bull trout were most often found in cold, low-gradient reaches upstream of glacial lakes. Our results indicate that complex stream habitats in sub-drainages free of non-native species are important to the persistence of native salmonids in western Glacier National Park. Results from this study may help managers monitor and protect important habitats and populations, inform conservation and recovery programs, and guide non-native species suppression efforts in Glacier National Park and elsewhere.

  6. Investigations of Bull Trout (Salvelinus Confluentus), Steelhead Trout (Oncorhynchus Mykiss), and Spring Chinook Salmon (O. Tshawytscha) Interactions in Southeast Washington Streams. Final Report 1992.

    SciTech Connect

    Underwood, Keith D.

    1995-01-01

    The goal of this two year study was to determine if supplementation with hatchery reared steelhead trout (Oncorhynchus mykiss) and spring chinook salmon (O. tshawytscha) negatively impacted wild native bull trout (Salvelinus confluentus) through competitive interactions. Four streams with varying levels of fish supplementation activity were sampled in Southeast Washington. Tasks performed during this study were population density, relative abundance, microhabitat utilization, habitat availability, diet analysis, bull trout spawning ground surveys, radio telemetry of adult bull trout, and growth analysis. Results indicate that bull trout overlapped geographically with the supplemented species in each of the study streams suggesting competition among species was possible. Within a stream, bull trout and the supplemented species utilized dissimilar microhabitats and microhabitat utilization by each species was the same among streams suggesting that there was no shifts in microhabitat utilization among streams. The diet of bull trout and O. mykiss significantly overlapped in each of the study streams. The stream most intensely supplemented contained bull trout with the slowest growth and the non-supplemented stream contained bull trout with the fastest growth. Conversely, the stream most intensely supplemented contain steelhead with the fastest growth and the non-supplemented stream contained steelhead with the slowest growth. Growth indicated that bull trout may have been negatively impacted from supplementation, although other factors may have contributed. At current population levels, and current habitat quantity and quality, no impacts to bull trout as a result of supplementation with hatchery reared steelhead trout and spring chinook salmon were detected. Project limitations and future research recommendations are discussed.

  7. Bull Trout Life History, Genetics, Habitat Needs, and Limiting Factors in Central and Northeast Oregon, Annual Report 2000.

    SciTech Connect

    Hemmingsen, Alan R.; Gunckel, Stephanie L.; Sankovich, Paul M.; Howell, Philip J.

    2001-11-01

    This section describes work accomplished in 2000 that continued to address two objectives of this project. These objectives are (1) determine the distribution of juvenile and adult bull trout Salvelinus confluentus and habitats associated with that distribution, and (2) determine fluvial and resident bull trout life history patterns. Completion of these objectives is intended through studies of bull trout in the Grande Ronde, Walla Walla, and John Day basins. These basins were selected because they provide a variety of habitats, from relatively degraded to pristine, and bull trout populations were thought to vary from relatively depressed to robust. In all three basins we continued to monitor the movements of bull trout with radio transmitters applied in 1998 (Hemmingsen, Bellerud, Gunckel and Howell 2001) and 1999 (Hemmingsen, Gunckel and Howell 2001). No new radio transmitters were applied to bull trout of the upper John Day River subbasin, Mill Creek (Walla Walla Basin), or the Grande Ronde Basin in 2000. We did implant radio transmitters in two bull trout incidentally captured in the John Day River near the confluence of the North Fork John Day River. In Mill Creek, we used traps to capture migrant bull trout to obtain data for the third successive year in this stream. With these traps, we intended to determine the timing of bull trout movements both upstream and downstream, and to determine the relative abundance, size and age of migrant fish. Because we captured migrant bull trout with traps for three years in the upper John Day River and its tributaries (Hemmingsen, Bellerud, Buchanan, Gunckel, Shappart and Howell 2001; Hemmingsen, Bellerud, Gunckel and Howell 2001; Hemmingsen, Gunckel and Howell 2001) and traps were no longer needed to capture bull trout for radio-tagging, no traps were operated in the John Day Basin in 2000.

  8. Marine Habitat Use by Anadromous Bull Trout from the Skagit River, Washington

    USGS Publications Warehouse

    Hayes, Michael C.; Rubin, Steve P.; Reisenbichler, Reginald; Goetz, Fred A.; Jeanes, Eric; McBride, Aundrea

    2011-01-01

    Acoustic telemetry was used to describe fish positions and marine habitat use by tagged bull trout Salvelinus confluentus from the Skagit River, Washington. In March and April 2006, 20 fish were captured and tagged in the lower Skagit River, while 15 fish from the Swinomish Channel were tagged during May and June. Sixteen fish tagged in 2004 and 2005 were also detected during the study. Fish entered Skagit Bay from March to May and returned to the river from May to August. The saltwater residency for the 13 fish detected during the out-migration and return migration ranged from 36 to 133 d (mean ± SD, 75 ± 22 d). Most bull trout were detected less than 14 km (8.5 ± 4.4 km) from the Skagit River, and several bay residents used the Swinomish Channel while migrating. The bull trout detected in the bay were associated with the shoreline (distance from shore, 0.32 ± 0.27 km) and occupied shallow-water habitats (mean water column depth, Zostera sp.) vegetation classes made up more than 70% of the area used by bull trout. Our results will help managers identify specific nearshore areas that may require further protection to sustain the unique anadromous life history of bull trout.

  9. Bull Trout Population Assessment in the White Salmon and Klickitat Rivers, Columbia River Gorge, Washington, 2001 Annual Report.

    SciTech Connect

    Thiesfeld, Steven L.; McPeak, Ronald H.; McNamara, Brian S.; Honanie, Isadore

    2002-01-01

    We utilized night snorkeling and single pass electroshocking to determine the presence or absence of bull trout Salvelinus confluentus in 26 stream reaches (3,415 m) in the White Salmon basin and in 71 stream reaches (9,005 m) in the Klickitat River basin during summer and fall 2001. We did not find any bull trout in the White Salmon River basin. In the Klickitat River basin, bull trout were found only in the West Fork Klickitat River drainage. We found bull trout in two streams not previously reported: Two Lakes Stream and an unnamed tributary to Fish Lake Stream (WRIA code number 30-0550). We attempted to capture downstream migrant bull trout in the West Fork Klickitat River by fishing a 1.5-m rotary screw trap at RM 4.3 from July 23 through October 17. Although we caught other salmonids, no bull trout were captured. The greatest limiting factor for bull trout in the West Fork Klickitat River is likely the small amount of available habitat resulting in a low total abundance, and the isolation of the population. Many of the streams are fragmented by natural falls, which are partial or complete barriers to upstream fish movement. To date, we have not been able to confirm that the occasional bull trout observed in the mainstem Klickitat River are migrating upstream into the West Fork Klickitat River.

  10. Evaluate Bull Trout Movements in the Tucannon and Lower Snake Rivers, 2002-2003 Annual Report.

    SciTech Connect

    Faler, Michael P.; Mendel, Glen W.; Fulton, Carl

    2004-04-01

    We collected 279 adult bull trout (Salvelinus confluentus) in the Tucannon River during the Spring and Fall of 2003. Passive Integrated Transponder (PIT) tags were inserted in 191 of them, and we detected existing PIT tags in an additional 31bull trout. Thirty five of these were also surgically implanted with radio-tags, and we monitored the movements of these fish throughout the year. Fourteen radio-tags were recovered shortly after tagging, and as a result, 21 remained in the river through December 31, 2003. Four bull trout that were radio-tagged in spring 2002 were known to survive and carry their tags through the spring and/or summer of 2003. One of these fish spent the winter near river mile (RM) 13.0; the other 3 over-wintered in the vicinity of the Tucannon Hatchery between RM 34 and 36. Twenty-one radio tags from bull trout tagged in 2002 were recovered during the spring and summer, 2003. These tags became stationary the winter of 2002/2003, and were recovered between RM 11 and 55. We were unable to recover the remaining 15 tags from 2002. During the month of July, radio-tagged bull trout exhibited a general upstream movement into the upper reaches of the Tucannon subbasin. We observed some downstream movements of radio-tagged bull trout in mid to late September and throughout October. By late November and early December, radio tagged bull trout were relatively stationary, and were distributed from the headwaters downstream to river mile 6.4, near Lower Monumental Pool. As in 2002, we did not conduct work associated with objectives 2, 3, or 4 of this study, because we were unable to monitor migratory movement of radio-tagged bull trout into the Federal hydropower system on the mainstem Snake River. Transmission tests of submerged ATS model F1830 radio-tags in Lower Granite Pool showed that audible detection and individual tag identification was possible at depths of 20 and 30 ft. Tests were conducted using an ATS R-4000 Receiver equipped with an ''H

  11. Incorporating movement patterns to improve survival estimates for juvenile bull trout

    USGS Publications Warehouse

    Bowerman, Tracy; Budy, Phaedra

    2012-01-01

    Populations of many fish species are sensitive to changes in vital rates during early life stages, but our understanding of the factors affecting growth, survival, and movement patterns is often extremely limited for juvenile fish. These critical information gaps are particularly evident for bull trout Salvelinus confluentus, a threatened Pacific Northwest char. We combined several active and passive mark–recapture and resight techniques to assess migration rates and estimate survival for juvenile bull trout (70–170 mm total length). We evaluated the relative performance of multiple survival estimation techniques by comparing results from a common Cormack–Jolly–Seber (CJS) model, the less widely used Barker model, and a simple return rate (an index of survival). Juvenile bull trout of all sizes emigrated from their natal habitat throughout the year, and thereafter migrated up to 50 km downstream. With the CJS model, high emigration rates led to an extreme underestimate of apparent survival, a combined estimate of site fidelity and survival. In contrast, the Barker model, which allows survival and emigration to be modeled as separate parameters, produced estimates of survival that were much less biased than the return rate. Estimates of age-class-specific annual survival from the Barker model based on all available data were 0.218±0.028 (estimate±SE) for age-1 bull trout and 0.231±0.065 for age-2 bull trout. This research demonstrates the importance of incorporating movement patterns into survival analyses, and we provide one of the first field-based estimates of juvenile bull trout annual survival in relatively pristine rearing conditions. These estimates can provide a baseline for comparison with future studies in more impacted systems and will help managers develop reliable stage-structured population models to evaluate future recovery strategies.

  12. Evaluate Bull Trout Movements in the Tucannon and Lower Snake Rivers, 2001-2002 Annual Report.

    SciTech Connect

    Faler, Michael P.; Mendel, Glen W.; Fulton, Carl

    2003-06-01

    We collected, radio-tagged, and PIT-tagged 41 bull trout at the Tucannon River Hatchery trap from May 17, through June 14, 2002. An additional 65 bull trout were also collected and PIT tagged by June 24, at which time we ceased PIT tagging operations because water temperatures were reaching 16.0 C or higher on a regular basis. Six radio-tags were recovered shortly after tagging, and as a result, 35 remained in the river through November 30, 2002. During the month of July, radio-tagged bull trout exhibited a general upstream movement into the upper reaches of the Tucannon Subbasin. We began to observe some downstream movements of radio-tagged bull trout in mid to late September and throughout October. These movements appeared to be associated with post spawning migrations. As of November 30, radio tagged bull trout were relatively stationary, and distributed from the headwaters downstream to river mile 11.3, near Pataha Creek. None of the radio-tagged bull trout left the Tucannon Subbasin and entered the federal hydropower system on the mainstem Snake River. We conducted some initial transmission tests of submerged radio tags at depths of 25, 35, 45, and 55 ft. in Lower Monumental Pool to test our capability of detection at these depths. Equipment used included Lotek model MCFT-3A transmitters, an SRX 400 receiver, a 4 element Yagi antenna, and a Lotek ''H'' antenna. Test results indicated that depth transmission of these tags was poor; only the transmitter placed at 25 ft. was audibly detectable.

  13. Bull Trout life History, Genetics, Habitat Needs, and Limiting Factors in Central and Northeast Oregon, Annual Report 1995.

    SciTech Connect

    Hemmingsen, Alan R.; Buchanan, David V.; Howell, Philip J.

    1996-03-01

    To fulfill one objective of the present study, genetic characteristics of Oregon bull trout will be determined by analysis of mitochondrial and nuclear DNA. During 1995, the authors collected and sampled a total of 1,217 bull trout from 46 streams in the Columbia River Basin. DNA analysis of those samples will be conducted at University of Montana. They primarily sampled juvenile fish near natal areas to increase the likelihood of identifying discrete populations while minimizing risk of injury to large spawners. Fork lengths of all fish sampled ranged from 2.6 to 60.5 cm with a median of 12 cm. Eighty-four percent of all bull trout sampled were less than 19 cm while two percent were larger than 27 cm. Bull trout were collected by several methods, mostly by electrofishing. Eighty-six percent of all bull trout sampled were collected by electrofishing with a programmable waveform electrofisher. They observed injuries caused by electrofishing to 8% of that proportion. Based on preliminary analysis, no waveform combination used appeared less injurious than others. Highest voltages appeared less injurious than some that were lower. Frequency of electrofishing injury was significantly correlated to fork length over the range-from 4 to 26 cm. There were indications for substantial risk for such injury to bull trout larger than 26 cm. Other species found in association with bull trout included chinook salmon Oncorhynchus tshawytscha, mountain whitefish Prosopium williamsoni, rainbow trout Oncorhynchus mykiss, sculpins Cottus spp., cutthroat trout Oncorhynchus clarki, non-native brook trout Salvelinus fontinalis, and tailed frogs Ascaphus truei. Rainbow trout was the species most frequently associated with bull trout. No injury or mortality was observed for any of the associated species captured.

  14. Bull Trout Life History, Genetics, Habitat Needs, and Limiting Factors in Central and Northeast Oregon, Annual Report 2001.

    SciTech Connect

    Hemmingsen, Alan R.; Gunckel, Stephanie L.; Sankovich, Paul M.; Howell, Philip J.

    2002-12-01

    Bull trout Salvelinus confluentus exhibit a number of life history strategies. Stream-resident bull trout complete their life cycle in their natal tributaries. Migratory bull trout spawn in tributary streams where juvenile fish usually spend from one to four years before migrating to either a larger river (fluvial) or lake (adfluvial) where they rear before returning to the tributary stream to spawn (Fraley and Shepard 1989). These migratory forms occur where conditions allow movement from spawning locations to downstream waters that provide greater foraging opportunities (Dunham and Rieman 1999). Resident and migratory forms may occur together, and either form can produce resident or migratory offspring (Rieman and McIntyre 1993). The ability to migrate is important to the persistence of local bull trout populations (Rieman and McIntyre 1993). The identification of migratory corridors can help focus habitat protection efforts. Determining the life history form(s) that comprise local populations, the timing of seasonal movements, and the geographic extent of these movements are critical to bull trout protection and recovery efforts. This section describes work accomplished in 2001 that continued to address two objectives of this project. These objectives are (1) determine the distribution of juvenile and adult bull trout and habitats associated with that distribution, and (2) determine fluvial and resident bull trout life history patterns. Completion of these objectives is intended through studies of bull trout in the Grande Ronde, Walla Walla, and John Day basins. These basins were selected because they provide a variety of habitats, from relatively degraded to pristine, and bull trout populations were thought to vary from relatively depressed to robust. In the Grande Ronde and Walla Walla basins, we continued to monitor the movements of bull trout with radio transmitters applied in 1998 (Hemmingsen, Bellerud, Gunckel and Howell 2001) and 1999 (Hemmingsen, Gunckel

  15. Evaluate Bull Trout Movements in the Tucannon and Lower Snake Rivers, 2004 Annual Report.

    SciTech Connect

    Faler, Michael P.; Mendel, Glen W.; Fulton, Carl

    2005-11-01

    We sampled and released 313 bull trout (Salvelinus confluentus) from the Tucannon River in 2004. Passive Integrated Transponder (PIT) tags were inserted in 231 of these individuals, and we detected existing PIT tags in an additional 44 bull trout. Twenty-five of these were also surgically implanted with radio-tags, and we monitored the movements of these fish throughout the year. Ten bull trout that were radio-tagged in 2003 were known to survive and carry their tags through the spring of 2004. One of these fish outmigrated into the Snake River in the fall, and remained undetected until February, when it's tag was located near the confluence of Alkali Flat Creek and the Snake River. The remaining 9 fish spent the winter between Tucannon River miles 2.1 (Powers Road) and 36.0 (Tucannon Fish Hatchery). Seven of these fish retained their tags through the summer, and migrated to known spawning habitat prior to September 2004. During June and July, radio-tagged bull trout again exhibited a general upstream movement into the upper reaches of the Tucannon subbasin. As in past years, we observed some downstream movements of radio-tagged bull trout in mid to late September and throughout October, suggesting post spawning outmigrations. By late November and early December, radio tagged bull trout were relatively stationary, and were distributed from river mile 42 at Camp Wooten downstream to river mile 17, near the Highway 12 bridge. As in previous years, we did not collect data associated with objectives 2, 3, or 4 of this study, because we were unable to monitor migratory movement of radio-tagged bull trout into the vicinity of the hydropower dams on the main stem Snake River. Transmission tests of submerged Lotek model NTC-6-2 nano-tags in Lower Granite Pool showed that audible detection and individual tag identification was possible at depths of 20, 30, and 40 ft. We were able to maintain tag detection and code separation at all depths from both a boat and 200 ft. above

  16. Winter diel habitat use and movement by subadult bull trout in the upper Flathead River, Montana

    USGS Publications Warehouse

    Muhlfeld, Clint C.; Glutting, Steve; Hunt, Rick; Daniels, Durae; Marotz, Brian

    2003-01-01

    We evaluated the diel habitat use and movement of subadult bull trout Salvelinus confluentus by use of radiotelemetry during winter in the upper Flathead River, Montana. Of the 13 monitored bull trout, 12 (92%) made at least one diel movement to other habitat locations during their respective day–night tracking surveys and moved an average of 73% of the time. The median distance moved from day to night locations by the mobile fish was 86 m (range, 27–594 m). Diel shifts in habitat use by nine of the tagged fish were related to light intensity; nocturnal emergence generally commenced immediately after the onset of night, and daytime concealment occurred at daybreak. When diel shifts in microhabitat use occurred, subadult bull trout moved from deep, midchannel areas during the day to shallow, low-velocity areas along the channel margins without overhead cover at night. Resource managers who wish to protect the overwintering habitat features preferred by subadult bull trout in the upper Flathead River should use natural flow management strategies that maximize and stabilize channel margin habitats at night.

  17. Conditions for growth and survival of bull trout in Beulah Reservoir, Oregon. Annual report 2002

    USGS Publications Warehouse

    Petersen, J.H.; Kofoot, E.E.; Rose, B.

    2003-01-01

    The Bureau of Reclamation (BOR) constructed Agency Valley Dam on the North Fork of the Malheur River in 1934-35, creating Beulah Reservoir. The project is operated and maintained by the Vale Irrigation District for irrigation and downstream flood control. There is currently no formal agreement for a minimum pool level at Beulah Reservoir, but project operators of Agency Valley Dam and BOR are considering management alternatives. Although the project is not operated for fish and wildlife values, the reservoir supports a rainbow trout Oncorhynchus mykiss fishery and also seasonally harbors an adfluvial population of bull trout Salvelinus confluentus (Oregon Department of Fish and Wildlife [ODFW], unpublished data). Bull trout were listed by the USFWS as a threatened species throughout the Columbia and Klamath river basins in 1998, and Oregon has listed the North Fork Malheur River population “Of Special Concern”.

  18. Conditions for growth and survival of bull trout in Beulah Reservoir, Oregon. Annual report 2001

    USGS Publications Warehouse

    Petersen, James H.; Kofoot, Eric E.

    2002-01-01

    The Bureau of Reclamation (BOR) constructed Agency Valley Dam on the North Fork of the Malheur River in 1934-35, creating Beulah Reservoir. The project is operated and maintained by the Vale Irrigation District for irrigation and downstream flood control, with no minimum pool or outflow operational criteria. Although the project is not operated for fish and wildlife values, the reservoir supports a rainbow trout Oncorhynchus mykiss fishery and also seasonally harbors an adfluvial population of bull trout Salvelinus confluentus (Oregon Department of Fish and Wildlife [ODFW]; Burns Paiute Tribe). Bull trout were listed by the USFWS as a threatened species throughout the Columbia and Klamath river basins in 1998, and Oregon has listed the North Fork Malheur River population “Of Special Concern”.

  19. Minimum Pool and Bull Trout Prey Base Investigations at Beulah Reservoir - Final Report for 2008

    USGS Publications Warehouse

    Rose, Brien P.; Mesa, Matthew G.

    2009-01-01

    Beulah Reservoir in southeastern Oregon provides irrigation water to nearby farms and supports an adfluvial population of threatened bull trout (Salvelinus confluentus). Summer drawdowns in the reservoir could affect forage fish production and overwintering bull trout. To assess the impacts of drawdown, we sampled fish, invertebrates, and water-quality variables seasonally during 2006-08. In 2006, the summer drawdown was about 68 percent of full pool, which was less than a typical drawdown of 85 percent. We detected few changes in pelagic invertebrate densities, and catch rates, abundance, and sizes of fish when comparing values from spring to values from fall. We did note that densities of benthic insects in areas that were dewatered annually were lower than those from areas that were not dewatered annually. In 2007, the drawdown was 100 percent (to run-of-river level) and resulted in decreases in abundance of invertebrates as much as 96 percent, decreases in catch rates of fish as much as 80 percent, decreases in abundance of redside shiners (Richardsonius balteatus) and northern pikeminnow (Ptychocheilus oregonensis) as much as 93 percent, and decreased numbers of small fish in catches. In the fall 2007, we estimated the total biomass of forage fish to be 76 kilograms, or about one-quarter of total biomass of forage fish in 2006. Bioenergetics modeling suggested that ample forage for about 1,000 bull trout would exist after a moderate drawdown, but that forage remaining after a complete dewatering would not be sufficient for a population one-fifth the size. Our results indicate that drawdowns in Beulah Reservoir affect the aquatic community and perhaps the health and well-being of bull trout. The severity of effects depends on the extent of drawdown, population size of bull trout, and perhaps other factors.

  20. Genetic diversity is related to climatic variation and vulnerability in threatened bull trout.

    PubMed

    Kovach, Ryan P; Muhlfeld, Clint C; Wade, Alisa A; Hand, Brian K; Whited, Diane C; DeHaan, Patrick W; Al-Chokhachy, Robert; Luikart, Gordon

    2015-02-06

    Understanding how climatic variation influences ecological and evolutionary processes is crucial for informed conservation decision-making. Nevertheless, few studies have measured how climatic variation influences genetic diversity within populations or how genetic diversity is distributed across space relative to future climatic stress. Here, we tested whether patterns of genetic diversity (allelic richness) were related to climatic variation and habitat features in 130 bull trout (Salvelinus confluentus) populations from 24 watersheds (i.e., ~4-7th order river subbasins) across the Columbia River Basin, USA. We then determined whether bull trout genetic diversity was related to climate vulnerability at the watershed scale, which we quantified on the basis of exposure to future climatic conditions (projected scenarios for the 2040s) and existing habitat complexity. We found a strong gradient in genetic diversity in bull trout populations across the Columbia River Basin, where populations located in the most upstream headwater areas had the greatest genetic diversity. After accounting for spatial patterns with linear mixed models, allelic richness in bull trout populations was positively related to habitat patch size and complexity, and negatively related to maximum summer temperature and the frequency of winter flooding. These relationships strongly suggest that climatic variation influences evolutionary processes in this threatened species and that genetic diversity will likely decrease due to future climate change. Vulnerability at a watershed scale was negatively correlated with average genetic diversity (r = -0.77; P < 0.001); watersheds containing populations with lower average genetic diversity generally had the lowest habitat complexity, warmest stream temperatures, and greatest frequency of winter flooding. Together, these findings have important conservation implications for bull trout and other imperiled species. Genetic diversity is already

  1. Genetic diversity is related to climatic variation and vulnerability in threatened bull trout

    USGS Publications Warehouse

    Kovach, Ryan; Muhlfeld, Clint C.; Wade, Alisa A.; Hand, Brian K.; Whited, Diane C.; DeHaan, Patrick W.; Al-Chokhachy, Robert K.; Luikart, Gordon

    2015-01-01

    Understanding how climatic variation influences ecological and evolutionary processes is crucial for informed conservation decision-making. Nevertheless, few studies have measured how climatic variation influences genetic diversity within populations or how genetic diversity is distributed across space relative to future climatic stress. Here, we tested whether patterns of genetic diversity (allelic richness) were related to climatic variation and habitat features in 130 bull trout (Salvelinus confluentus) populations from 24 watersheds (i.e., ~4–7th order river subbasins) across the Columbia River Basin, USA. We then determined whether bull trout genetic diversity was related to climate vulnerability at the watershed scale, which we quantified on the basis of exposure to future climatic conditions (projected scenarios for the 2040s) and existing habitat complexity. We found a strong gradient in genetic diversity in bull trout populations across the Columbia River Basin, where populations located in the most upstream headwater areas had the greatest genetic diversity. After accounting for spatial patterns with linear mixed models, allelic richness in bull trout populations was positively related to habitat patch size and complexity, and negatively related to maximum summer temperature and the frequency of winter flooding. These relationships strongly suggest that climatic variation influences evolutionary processes in this threatened species and that genetic diversity will likely decrease due to future climate change. Vulnerability at a watershed scale was negatively correlated with average genetic diversity (r = −0.77;P < 0.001); watersheds containing populations with lower average genetic diversity generally had the lowest habitat complexity, warmest stream temperatures, and greatest frequency of winter flooding. Together, these findings have important conservation implications for bull trout and other imperiled species. Genetic diversity is already

  2. Bull Trout Distribution and Abundance in the Waters on and Bordering the Warm Springs Indian Reservation, 2001 Annual Report.

    SciTech Connect

    Brun, Christopher V.

    2002-01-01

    The range of bull trout (Salvelinus confluentus) in the Deschutes River basin has decreased from historic levels due to many factors including dam construction, habitat degradation, brook trout introduction and eradication efforts. While the bull trout population appears to be stable in the Metolius River-Lake Billy Chinook system they have been largely extirpated from the upper Deschutes River (Buchanan et al. 1997). Little was known about bull trout in the lower Deschutes basin until BPA funded project No.9405400 began during 1998. In this progress report we describe the findings from the fourth year (2001) of the multi-year study aimed at determining the life history, habitat needs and limiting factors of bull trout in the lower Deschutes subbasin. Juvenile bull trout and brook trout (Salvelinus fontinalis) relative abundance was assessed in the Warm Springs River and Shitike Creek by night snorkeling. In the Warm Springs R. juvenile bull trout were slightly more numerous than brook trout, however, both were found in low densities. Relative densities of both species were the lowest observed since surveys began in 1999. Relative densities of juvenile bull trout and brook trout increased in Shitike Cr. Juvenile bull trout vastly out numbered brook trout in Shitike Cr. The utility of using index reaches to monitor trends in juvenile bull trout and brook trout relative abundance was assessed in the Warm Springs R. for the third year. Mean relative densities of juvenile bull trout within the index reaches was slightly higher than what was observed in the 2.4 km control reach. However, the mean relative density of brook trout in the 2.4 km control reach was slightly higher than what was observed in within the index reaches. Habitat use by both juvenile bull trout and brook trout was determined in the Warm Springs R. Juvenile bull trout and brook trout occupied pools more frequently than glides, riffles and rapids. However, pools accounted for only a small percentage

  3. Bull Trout Distribution and Abundance in the Waters on and Bordering the Warm Springs Reservation : 2002 Annual Report.

    SciTech Connect

    Brun, Christopher V.; Dodson, Rebekah

    2003-03-01

    The range of bull trout (Salvelinus confluentus) in the Deschutes River basin has decreased from historic levels due to many factors including dam construction, habitat degradation, brook trout introduction and eradication efforts. While the bull trout population appears to be healthy in the Metolius River-Lake Billy Chinook system they have been largely extirpated from the upper Deschutes River (Buchanan et al. 1997). Little was known about bull trout in the lower Deschutes basin until BPA funded project No.9405400 began during 1998. In this progress report we describe the findings to date from this multi-year study aimed at determining the life history, habitat needs and limiting factors of bull trout in the lower Deschutes subbasin. Juvenile bull trout and brook trout (Salvelinus fontinalis) relative abundance has been assessed in the Warm Springs River and Shitike Creek since 1999. In the Warm Springs R. the relative densities of juvenile bull trout and brook trout were .003 fish/m{sup 2} and .001 fish/m{sup 2} respectively during 2002. These densities were the lowest recorded in the Warm Springs River during the period of study. In Shitike Cr. the relative densities of juvenile bull trout and brook trout were .025 fish/m{sup 2} and .01 fish/m{sup 2} respectively during 2002. The utility of using index reaches to monitor trends in juvenile bull trout and brook trout relative abundance in the Warm Springs R. has been assessed since 1999. During 2002 the mean relative densities of juvenile bull trout within the 2.4 km study area was higher than what was observed in four index reaches. However, the mean relative densities of brook trout was slightly higher in the index reaches than what was observed in the 2.4 km study area. Habitat use by both juvenile bull trout and brook trout was determined in the Warm Springs R. Juvenile bull trout and brook trout were most abundant in pools and glides. However pools and glides comprised less than 20% of the available habitat

  4. Evaluation of the Life History of Native Salmonids in the Malheur River Basin; Cooperative Bull Trout/Redband Trout Research Project, 1999-2000 Annual Report.

    SciTech Connect

    Schwabe, Lawrence; Tiley, Mark; Perkins, Raymond R.

    2000-11-01

    The purpose of this study is to document the seasonal distribution of adult/sub-adult bull trout (Salvelinus confluentus) in the Malheur River basin. Due to the decline of bull trout in the Columbia Basin, the United States Fish and Wildlife Service listed bull trout as a threatened species in June 1998. Past land management activities; construction of dams; and fish eradication projects in the North Fork and Middle Fork Malheur River by poisoning have worked in concert to cumulatively impact native species in the Malheur Basin (Bowers et. al. 1993). Survival of the remaining bull trout populations is severely threatened (Buchanan 1997). 1999 Research Objects are: (1) Document the migratory patterns of adult/sub-adult bull trout in the North Fork Malheur River; (2) Determine the seasonal bull trout use of Beulah Reservoir and bull trout entrainment; and (3) Timing and location of bull trout spawning in the North Fork Malheur River basin. The study area includes the Malheur basin from the mouth of the Malheur River located near Ontario, Oregon to the headwaters of the North Fork Malheur River (Map 1). All fish collected and most of the telemetry effort was done on the North Fork Malheur River subbasin (Map 2). Fish collection was conducted on the North Fork Malheur River at the tailwaters of Beulah Reservoir (RK 29), Beulah Reservoir (RK 29-RK 33), and in the North Fork Malheur River at Crane Crossing (RK 69) to the headwaters of the North Fork Malheur. Radio telemetry was done from the mouth of the Malheur River in Ontario, Oregon to the headwaters of the North Fork Malheur. This report will reflect all migration data collected from 3/1/99 to 12/31/99.

  5. Bull Trout Population and Habitat Surveys in the Middle Fork Willamette and McKenzie Rivers, Annual Report 2002.

    SciTech Connect

    Seals, Jason; Reis, Kelly

    2003-10-01

    Bull trout in the Willamette River Basin were historically distributed throughout major tributaries including the Middle Fork Willamette and McKenzie rivers. Habitat degradation, over-harvest, passage barriers, fish removal by rotenone, and hybridization and competition with non-native brook trout are all likely factors that have led to the decline of bull trout in the Willamette Basin (Ratliff and Howell 1992). The U.S. Fish and Wildlife Service listed the Columbia River bull trout population segment as Threatened under the federal Endangered Species Act in 1998. Four bull trout populations were isolated in the upper Willamette River following the construction of flood control dams on the South Fork McKenzie River, McKenzie River, and Middle Fork Willamette River that created Cougar, Trail Bridge, and Hills Creek reservoirs. Buchanan et al. (1997) described the population in the main stem McKenzie as 'of special concern', the South Fork McKenzie population as 'high risk of extinction', the population above Trail Bridge Reservoir as 'high risk of extinction', and bull trout in the Middle Fork Willamette as 'probably extinct'. Various management efforts such as strict angling regulations and passage improvement projects have been implemented to stabilize and rehabilitate bull trout habitat and populations in the McKenzie River over the past 10 years. Since 1997, bull trout fry from Anderson Creek on the upper McKenzie River have been transferred to the Middle Fork Willamette basin above Hills Creek Reservoir in an attempt to re-establish a reproducing bull trout population. This project was developed in response to concerns over the population status and management of bull trout in the McKenzie and Middle Fork Willamette Rivers by the Oregon Department of Fish and Wildlife during the early 1990s. The project was conducted under measure 9.3G(2) of the Columbia Basin Fish and Wildlife Program to monitor the status, life history, habitat needs, and limiting factors for

  6. Assessing the feasibility of native fish reintroductions: a framework and example applied to bull trout in the Clackamas River, Oregon

    USGS Publications Warehouse

    Dunham, Jason B.; Gallo, Kirsten

    2008-01-01

    In a species conservation context, translocations can be an important tool, but they frequently fail to successfully establish new populations. We consider the case of reintroductions for bull trout (Salvelinus confluentus), a federally-listed threatened species with a widespread but declining distribution in western North America. Our specific objectives in this work were to: 1) develop a general framework for assessing the feasibility of reintroduction for bull trout, 2) provide a detailed example of implementing this framework to assess the feasibility of reintroducing bull trout in the Clackamas River, Oregon, and 3) discuss the implications of this effort in the more general context of fish reintroductions as a conservation tool. Review of several case histories and our assessment of the Clackamas River suggest that an attempt to reintroduce bull trout could be successful, assuming adequate resources are committed to the subsequent stages of implementation, monitoring, and evaluation.

  7. Bull trout (Salvelinus confluentus) movement in relation to water temperature, season, and habitat features in Arrowrock Reservoir, Idaho, 2012

    USGS Publications Warehouse

    Maret, Terry R.; Schultz, Justin E.

    2013-01-01

    Acoustic telemetry was used to determine spring to summer (April–August) movement and habitat use of bull trout (Salvelinus confluentus) in Arrowrock Reservoir (hereafter “Arrowrock”), a highly regulated reservoir in the Boise River Basin of southwestern Idaho. Water management practices annually use about 86 percent of the reservoir water volume to satisfy downstream water demands. These practices might be limiting bull trout habitat and movement patterns. Bull trout are among the more thermally sensitive coldwater species in North America, and the species is listed as threatened throughout the contiguous United States under the Endangered Species Act. Biweekly water-temperature and dissolved-oxygen profiles were collected by the Bureau of Reclamation at three locations in Arrowrock to characterize habitat conditions for bull trout. Continuous streamflow and water temperature also were measured immediately upstream of the reservoir on the Middle and South Fork Boise Rivers, which influence habitat conditions in the riverine zones of the reservoir. In spring 2012, 18 bull trout ranging in total length from 306 to 630 millimeters were fitted with acoustic transmitters equipped with temperature and depth sensors. Mobile boat tracking and fixed receivers were used to detect released fish. Fish were tagged from March 28 to April 20 and were tracked through most of August. Most bull trout movements were detected in the Middle Fork Boise River arm of the reservoir. Fifteen individual fish were detected at least once after release. Water surface temperature at each fish detection location ranged from 6.0 to 16.2 degrees Celsius (°C) (mean=10.1°C), whereas bull trout body temperatures were colder, ranging from 4.4 to 11.6°C (mean=7.3°C). Bull trout were detected over deep-water habitat, ranging from 8.0 to 42.6 meters (m) (mean=18.1 m). Actual fish depths were shallower than total water depth, ranging from 0.0 to 24.5 m (mean=6.7 m). The last bull trout was

  8. Fragmentation of riverine systems: the genetic effects of dams on bull trout (Salvelinus confluentus) in the Clark Fork River system.

    PubMed

    Neraas, L P; Spruell, P

    2001-05-01

    Migratory bull trout (Salvelinus confluentus) historically spawned in tributaries of the Clark Fork River, Montana and inhabited Lake Pend Oreille as subadult and adult fish. However, in 1952 Cabinet Gorge Dam was constructed without fish passage facilities disrupting the connectivity of this system. Since the construction of this dam, bull trout populations in upstream tributaries have been in decline. Each year adult bull trout return to the base of Cabinet Gorge Dam when most migratory bull trout begin their spawning migration. However, the origin of these fish is uncertain. We used eight microsatellite loci to compare bull trout collected at the base of Cabinet Gorge Dam to fish sampled from both above and further downstream from the dam. Our data indicate that Cabinet Gorge bull trout are most likely individuals that hatched in above-dam tributaries, reared in Lake Pend Oreille, and could not return to their natal tributaries to spawn. This suggests that the risk of outbreeding depression associated with passing adults over dams in the Clark Fork system is minimal compared to the potential genetic and demographic benefits to populations located above the dams.

  9. Landscape influences on genetic differentiation among bull trout populations in a stream-lake network.

    PubMed

    Meeuwig, Michael H; Guy, Christopher S; Kalinowski, Steven T; Fredenberg, Wade A

    2010-09-01

    This study examined the influence of landscape heterogeneity on genetic differentiation between migratory bull trout (Salvelinus confluentus) populations in Glacier National Park, Montana. An information-theoretic approach was used to compare different conceptual models of dispersal associated with barriers, different models of isolation by distance, and the combined effects of barriers, waterway distance, patch size, and intra- and inter-drainage distribution of populations on genetic differentiation between bull trout populations. The effect of distance between populations on genetic differentiation was best explained by partitioning the effects of mainstem and tributary stream sections. Models that categorized barriers as having a one-way effect (i.e. allowed downstream dispersal) or a two-way effect were best supported. Additionally, patch size and the distribution of populations among drainages influenced genetic differentiation. Genetic differentiation between bull trout populations in Glacier National Park is linked to landscape features that restrict dispersal. However, this analysis illustrates that modelling variability within landscape features, such as dispersal corridors, will benefit landscape genetic analyses. Additionally, the framework used for evaluating the effects of barriers must consider not just barrier presence, but also potential asymmetries in barrier effects with respect to the organism under investigation.

  10. Landscape influences on genetic differentiation among bull trout populations in a stream-lake network

    USGS Publications Warehouse

    Meeuwig, M.H.; Guy, C.S.; Kalinowski, S.T.; Fredenberg, W.A.

    2010-01-01

    This study examined the influence of landscape heterogeneity on genetic differentiation between migratory bull trout (Salvelinus confluentus) populations in Glacier National Park, Montana. An information-theoretic approach was used to compare different conceptual models of dispersal associated with barriers, different models of isolation by distance, and the combined effects of barriers, waterway distance, patch size, and intra- and inter-drainage distribution of populations on genetic differentiation between bull trout populations. The effect of distance between populations on genetic differentiation was best explained by partitioning the effects of mainstem and tributary stream sections. Models that categorized barriers as having a one-way effect (i.e. allowed downstream dispersal) or a two-way effect were best supported. Additionally, patch size and the distribution of populations among drainages influenced genetic differentiation. Genetic differentiation between bull trout populations in Glacier National Park is linked to landscape features that restrict dispersal. However, this analysis illustrates that modelling variability within landscape features, such as dispersal corridors, will benefit landscape genetic analyses. Additionally, the framework used for evaluating the effects of barriers must consider not just barrier presence, but also potential asymmetries in barrier effects with respect to the organism under investigation.

  11. Climate change and vulnerability of bull trout (Salvelinus confluentus) in a fire-prone landscape.

    USGS Publications Warehouse

    Falke, Jeffrey A.; Flitcroft, Rebecca L; Dunham, Jason B.; McNyset, Kristina M.; Hessburg, Paul F.; Reeves, Gordon H.

    2015-01-01

    Linked atmospheric and wildfire changes will complicate future management of native coldwater fishes in fire-prone landscapes, and new approaches to management that incorporate uncertainty are needed to address this challenge. We used a Bayesian network (BN) approach to evaluate population vulnerability of bull trout (Salvelinus confluentus) in the Wenatchee River basin, Washington, USA, under current and future climate and fire scenarios. The BN was based on modeled estimates of wildfire, water temperature, and physical habitat prior to, and following, simulated fires throughout the basin. We found that bull trout population vulnerability depended on the extent to which climate effects can be at least partially offset by managing factors such as habitat connectivity and fire size. Moreover, our analysis showed that local management can significantly reduce the vulnerability of bull trout to climate change given appropriate management actions. Tools such as our BN that explicitly integrate the linked nature of climate and wildfire, and incorporate uncertainty in both input data and vulnerability estimates, will be vital in effective future management to conserve native coldwater fishes.

  12. The fishing and natural mortality of large, piscivorous Bull Trout and Rainbow Trout in Kootenay Lake, British Columbia (2008–2013)

    PubMed Central

    Andrusak, Greg F.

    2017-01-01

    Background Estimates of fishing and natural mortality are important for understanding, and ultimately managing, commercial and recreational fisheries. High reward tags with fixed station acoustic telemetry provides a promising approach to monitoring mortality rates in large lake recreational fisheries. Kootenay Lake is a large lake which supports an important recreational fishery for large Bull Trout and Rainbow Trout. Methods Between 2008 and 2013, 88 large (≥500 mm) Bull Trout and 149 large (≥500 mm) Rainbow Trout were marked with an acoustic transmitter and/or high reward ($100) anchor tags in Kootenay Lake. The subsequent detections and angler recaptures were analysed using a Bayesian individual state-space Cormack–Jolly–Seber (CJS) survival model with indicator variable selection. Results The final CJS survival model estimated that the annual interval probability of being recaptured by an angler was 0.17 (95% CRI [0.11–0.23]) for Bull Trout and 0.14 (95% CRI [0.09–0.19]) for Rainbow Trout. The annual interval survival probability for Bull Trout was estimated to have declined from 0.91 (95% CRI [0.76–0.97]) in 2009 to just 0.46 (95% CRI [0.24–0.76]) in 2013. Rainbow Trout survival was most strongly affected by spawning. The annual interval survival probability was 0.77 (95% CRI [0.68–0.85]) for a non-spawning Rainbow Trout compared to 0.41 (95% CRI [0.30–0.53]) for a spawner. The probability of spawning increased with the fork length for both species and decreased over the course of the study for Rainbow Trout. Discussion Fishing mortality was relatively low and constant while natural mortality was relatively high and variable. The results indicate that angler effort is not the primary driver of short-term population fluctations in the Rainbow Trout abundance. Variation in the probability of Rainbow Trout spawning suggests that the spring escapement at the outflow of Trout Lake may be a less reliable index of abundance than previously

  13. An ecological risk assessment of the acute and chronic toxicity of the herbicide picloram to the threatened bull trout (Salvelinus confluentus) and the rainbow trout (Onchorhyncus mykiss).

    PubMed

    Fairchild, J F; Feltz, K P; Sappington, L C; Allert, A L; Nelson, K J; Valle, J

    2009-05-01

    We conducted acute and chronic toxicity studies of the effects of picloram acid on the threatened bull trout (Salvelinus confluentus) and the standard coldwater surrogate rainbow trout (Oncorhynchus mykiss). Juvenile fish were chronically exposed for 30 days in a proportional flow-through diluter to measured concentrations of 0, 0.30, 0.60, 1.18, 2.37, and 4.75 mg/L picloram. No mortality of either species was observed at the highest concentration. Bull trout were twofold more sensitive to picloram (30-day maximum acceptable toxic concentration of 0.80 mg/L) compared to rainbow trout (30-day maximum acceptable toxic concentration of 1.67 mg/L) based on the endpoint of growth. Picloram was acutely toxic to rainbow trout at 36 mg/L (96-h ALC50). The acute:chronic ratio for rainbow trout exposed to picloram was 22. The chronic toxicity of picloram was compared to modeled and measured environmental exposure concentrations (EECs) using a four-tiered system. The Tier 1, worst-case exposure estimate, based on a direct application of the current maximum use rate (1.1 kg/ha picloram) to a standardized aquatic ecosystem (water body of 1-ha area and 1-m depth), resulted in an EEC of 0.73 mg/L picloram and chronic risk quotients of 0.91 and 0.44 for bull trout and rainbow trout, respectively. Higher-tiered exposure estimates reduced chronic risk quotients 10-fold. Results of this study indicate that picloram, if properly applied according to the manufacturer's label, poses little risk to the threatened bull trout or rainbow trout in northwestern rangeland environments on either an acute or a chronic basis.

  14. An ecological risk assessment of the acute and chronic toxicity of the herbicide picloram to the threatened bull trout (salvelinus confluentus) and the rainbow trout (onchorhyncus mykiss)

    USGS Publications Warehouse

    Fairchild, J.F.; Feltz, K.P.; Sappington, L.C.; Allert, A.L.; Nelson, K.J.; Valle, J.

    2009-01-01

    We conducted acute and chronic toxicity studies of the effects of picloram acid on the threatened bull trout (Salvelinus confluentus) and the standard coldwater surrogate rainbow trout (Oncorhynchus mykiss). Juvenile fish were chronically exposed for 30 days in a proportional flow-through diluter to measured concentrations of 0, 0.30, 0.60, 1.18, 2.37, and 4.75 mg/L picloram. No mortality of either species was observed at the highest concentration. Bull trout were twofold more sensitive to picloram (30-day maximum acceptable toxic concentration of 0.80 mg/L) compared to rainbow trout (30-day maximum acceptable toxic concentration of 1.67 mg/L) based on the endpoint of growth. Picloram was acutely toxic to rainbow trout at 36 mg/L (96-h ALC50). The acute:chronic ratio for rainbow trout exposed to picloram was 22. The chronic toxicity of picloram was compared to modeled and measured environmental exposure concentrations (EECs) using a four-tiered system. The Tier 1, worst-case exposure estimate, based on a direct application of the current maximum use rate (1.1 kg/ha picloram) to a standardized aquatic ecosystem (water body of 1-ha area and 1-m depth), resulted in an EEC of 0.73 mg/L picloram and chronic risk quotients of 0.91 and 0.44 for bull trout and rainbow trout, respectively. Higher-tiered exposure estimates reduced chronic risk quotients 10-fold. Results of this study indicate that picloram, if properly applied according to the manufacturer's label, poses little risk to the threatened bull trout or rainbow trout in northwestern rangeland environments on either an acute or a chronic basis. ?? 2008 Springer Science+Business Media, LLC.

  15. Evaluation of Bull Trout Movements in the Tucannon and Lower Snake Rivers, 2002-2006 Project Completion Summary.

    SciTech Connect

    Faler, Michael P.; Mendel, Glen; Fulton, Carl

    2008-11-20

    The Columbia River Distinct Population Segment of bull trout (Salvelinus confluentus) was listed as threatened under the Endangered Species Act in 1998. One of the identified major threats to the species is fragmentation resulting from dams on over-wintering habitats of migratory subpopulations. A migratory subgroup in the Tucannon River appeared to utilize the Snake River reservoirs for adult rearing on a seasonal basis. As a result, a radio telemetry study was conducted on this subgroup from 2002-2006, to help meet Reasonable and Prudent Measures, and Conservation Recommendations associated with the lower Snake River dams in the FCRPS Biological Opinion, and to increase understanding of bull trout movements within the Tucannon River drainage. We sampled 1,109 bull trout in the Tucannon River; 124 of these were surgically implanted with radio tags and PIT tagged, and 681 were only PIT tagged. The remaining 304 fish were either recaptures, or released unmarked. Bull trout seasonal movements within the Tucannon River were similar to those described for other migratory bull trout populations. Bull trout migrated upstream in spring and early summer to the spawning areas in upper portions of the Tucannon River watershed. They quickly moved off the spawning areas in the fall, and either held or continued a slower migration downstream through the winter until early the following spring. During late fall and winter, bull trout were distributed in the lower half of the Tucannon River basin, down to and including the mainstem Snake River below Little Goose Dam. We were unable to adequately radio track bull trout in the Snake River and evaluate their movements or interactions with the federal hydroelectric dams for the following reasons: (1) none of our radio-tagged fish were detected attempting to pass a Snake River dam, (2) our radio tags had poor transmission capability at depths greater than 12.2 m, and (3) the sample size of fish that actually entered the Snake River

  16. Seasonal movement and habitat use by sub-adult bull trout in the upper Flathead River system, Montana

    USGS Publications Warehouse

    Muhlfeld, Clint C.; Marotz, Brian

    2005-01-01

    Despite the importance of large-scale habitat connectivity to the threatened bull trout Salvelinus confluentus, little is known about the life history characteristics and processes influencing natural dispersal of migratory populations. We used radiotelemetry to investigate the seasonal movements and habitat use by subadult bull trout (i.e., fish that emigrated from natal streams to the river system) tracked for varying durations from 1999 to 2002 in the upper Flathead River system in northwestern Montana. Telemetry data revealed migratory (N = 32 fish) and nonmigratory (N = 35 fish) behavior, indicating variable movement patterns in the subadult phase of bull trout life history. Most migrating subadults (84%) made rapid or incremental downriver movements (mean distance, 33 km; range, 6–129 km) to lower portions of the river system and to Flathead Lake during high spring flows and as temperatures declined in the fall and winter. Bull trout subadults used complex daytime habitat throughout the upper river system, including deep runs that contained unembedded boulder and cobble substrates, pools with large woody debris, and deep lake-influenced areas of the lower river system. Our results elucidate the importance of maintaining natural connections and a diversity of complex habitats over a large spatial scale to conserve the full expression of life history traits and processes influencing the natural dispersal of bull trout populations. Managers should seek to restore and enhance critical river corridor habitat and remove migration barriers, where possible, for recovery and management programs.

  17. Influences of body size and environmental factors on autumn downstream migration of bull trout in the Boise River, Idaho

    USGS Publications Warehouse

    Monnot, L.; Dunham, J.B.; Hoem, T.; Koetsier, P.

    2008-01-01

    Many fishes migrate extensively through stream networks, yet patterns are commonly described only in terms of the origin and destination of migration (e.g., between natal and feeding habitats). To better understand patterns of migration in bull trout,Salvelinus confluentus we studied the influences of body size (total length [TL]) and environmental factors (stream temperature and discharge) on migrations in the Boise River basin, Idaho. During the autumns of 2001-2003, we tracked the downstream migrations of 174 radio-tagged bull trout ranging in size from 21 to 73 cm TL. The results indicated that large bull trout (>30 cm) were more likely than small fish to migrate rapidly downstream after spawning in headwater streams in early autumn. Large bull trout also had a higher probability of arriving at the current terminus of migration in the system, Arrowrock Reservoir. The rate of migration by small bull trout was more variable and individuals were less likely to move into Arrowrock Reservoir. The rate of downstream migration by all fish was slower when stream discharge was greater. Temperature was not associated with the rate of migration. These findings indicate that fish size and environmentally related changes in behavior have important influences on patterns of migration. In a broader context, these results and other recent work suggest, at least in some cases, that commonly used classifications of migratory behavior may not accurately reflect the full range of behaviors and variability among individuals (or life stages) and environmental conditions. ?? Copyright by the American Fisheries Society 2008.

  18. VULNERABILITY OF BULL TROUT TO EARLY LIFE STAGE TOXICITY OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD) AND OTHER AHR AGONISTS

    EPA Science Inventory

    Population declines of bull trout, Salvelinus confluentus, have occurred in recent decades throughout much of the species' natural range in the Columbia River watershed and other river systems in western Canada. Bull trout in the U.S. are now listed as threatened under the Endang...

  19. Bull trout (Salvelinus confluentus) telemetry and associated habitat data collected in a geodatabase from the upper Boise River, southwestern Idaho

    USGS Publications Warehouse

    MacCoy, Dorene E.; Shephard, Zachary M.; Benjamin, Joseph R.; Vidergar, Dmitri T.; Prisciandaro, Anthony F.

    2017-03-23

    Bull trout (Salvelinus confluentus), listed as threatened under the Endangered Species Act, are among the more thermally sensitive of coldwater species in North America. The Boise River upstream of Arrowrock Dam in southwestern Idaho (including Arrowrock Reservoir) provides habitat for one of the southernmost populations of bull trout. The presence of the species in Arrowrock Reservoir poses implications for dam and reservoir operations. From 2011 to 2014, the Bureau of Reclamation and the U.S. Geological Survey collected fish telemetry data to improve understanding of bull trout distribution and movement in Arrowrock Reservoir and in the upper Boise River tributaries. The U.S. Geological Survey compiled the telemetry (fish location) data, along with reservoir elevation, river discharge, precipitation, and water-quality data in a geodatabase. The geodatabase includes metadata compliant with Federal Geographic Data Committee content standards. The Bureau of Reclamation plans to incorporate the data in a decision‑support tool for reservoir management.

  20. Bull Trout Forage Investigations in Beulah Reservoir, Oregon - Annual Report for 2006

    USGS Publications Warehouse

    Rose, Brien P.; Mesa, Mathew G.

    2009-01-01

    Beulah Reservoir on the north fork of the Malheur River in northeastern Oregon provides irrigation water to nearby farms and ranches and supports an adfluvial population of bull trout (Salvelinus confluentus), which are listed as threatened under the Endangered Species Act. Water management in Beulah Reservoir results in seasonal and annual fluctuations of water volume that may affect forage availability for bull trout. Because no minimum pool requirements currently exist, the reservoir is occasionally reduced to run-of-river levels, which may decimate forage fish populations and ultimately affect bull trout. We sampled fish and aquatic insects in Beulah Reservoir in the spring, before the annual drawdown of 2006, and afterward, in the late fall. We also collected samples 1.5 years after the reservoir was dewatered for three consecutive summers. Overall, the moderate drawdown of 2006 (32 percent of full pool) did not drastically alter the fish community in Beulah Reservoir. We did document, however, decreases in abundance and sizes of chironomids in areas of the reservoir that were frequently dewatered, increased catch rates of fish with gillnets, and decreases in population estimates for smaller fishes after drawdown. In 2006, after the dewaterings of 2002-04, species composition was similar to that prior to the dewaterings, but the size distributions of most species were biased toward small juvenile or subyearling fishes and larger fishes were rare. Our results indicate that repeated reservoir drawdown reduces aquatic insect forage for bull trout and probably affects forage fish populations at least temporarily. The high catch rates of juvenile fishes 1.5 years after consecutive dewaterings suggests good reproductive success for any remaining adult fish, and shows that the fish community in Beulah Reservoir is resilient to such disturbances. There is, however, a period of time after serious drawdowns before significant numbers of juvenile fishes start to appear

  1. Assessing the impacts of river regulation on native bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) habitats in the upper Flathead River, Montana, USA

    USGS Publications Warehouse

    Muhlfeld, Clint C.; Jones, Leslie A.; Kotter, D.; Miller, William J.; Geise, Doran; Tohtz, Joel; Marotz, Brian

    2012-01-01

    Hungry Horse Dam on the South Fork Flathead River, Montana, USA, has modified the natural flow regimen for power generation, flood risk management and flow augmentation for anadromous fish recovery in the Columbia River. Concern over the detrimental effects of dam operations on native resident fishes prompted research to quantify the impacts of alternative flow management strategies on threatened bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) habitats. Seasonal and life‐stage specific habitat suitability criteria were combined with a two‐dimensional hydrodynamic habitat model to assess discharge effects on usable habitats. Telemetry data used to construct seasonal habitat suitability curves revealed that subadult (fish that emigrated from natal streams to the river system) bull trout move to shallow, low‐velocity shoreline areas at night, which are most sensitive to flow fluctuations. Habitat time series analyses comparing the natural flow regimen (predam, 1929–1952) with five postdam flow management strategies (1953–2008) show that the natural flow conditions optimize the critical bull trout habitats and that the current strategy best resembles the natural flow conditions of all postdam periods. Late summer flow augmentation for anadromous fish recovery, however, produces higher discharges than predam conditions, which reduces the availability of usable habitat during this critical growing season. Our results suggest that past flow management policies that created sporadic streamflow fluctuations were likely detrimental to resident salmonids and that natural flow management strategies will likely improve the chances of protecting key ecosystem processes and help to maintain and restore threatened bull trout and westslope cutthroat trout populations in the upper Columbia River Basin.

  2. Nuclear DNA identification of migrating bull trout captured at the Puget Sound Energy diversion dam on the White River, Washington State.

    PubMed

    Baker, J D; Moran, P; Ladley, R

    2003-02-01

    Bull trout (Salvelinus confluentus) is a char listed as threatened under the United States Endangered Species Act throughout its range in the coterminous United States. Substantial morphological similarities between bull trout and Dolly Varden (S. malma) make field identification difficult. This has resulted in an incomplete understanding of their distribution and abundance in Washington State where these two species occur sympatrically. We used three diagnostic nuclear loci to determine the species of char collected at a trap on the White River in southern Puget Sound (Washington State, USA). Each of the 104 samples revealed the expected bull trout genotype at all three loci. This work presents three principle results: (i) the presence of a migratory bull trout population in southern Puget Sound; (ii) no evidence of migratory Dolly Varden over 3 years; and (iii) no evidence of hybridization was detected. These results also demonstrate how molecular markers can provide information essential to the conservation and management of these species.

  3. Bull trout in the Boundary System: managing connectivity and the feasibility of a reintroduction in the lower Pend Oreille River, northeastern Washington

    USGS Publications Warehouse

    Dunham, Jason B.; Taylor, Eric B.; Allendorf, Fred W.

    2014-01-01

    Assess the role of passage over Boundary Dam, in the context of other factors in the system that may influence the feasibility of establishing a self-sustaining bull trout population in the Boundary system.

  4. A framework for assessing the feasibility of native fish conservation translocations: Applications to threatened bull trout

    USGS Publications Warehouse

    Galloway, Benjamin T.; Muhlfeld, Clint C.; Guy, Christopher S.; Downs, Christopher C.; Fredenberg, Wade A.

    2016-01-01

    There is an urgent need to consider more aggressive and direct interventions for the conservation of freshwater fishes that are threatened by invasive species, habitat loss, and climate change. Conservation introduction (moving a species outside its indigenous range to other areas where conditions are predicted to be more suitable) is one type of translocation strategy that fisheries managers can use to establish new conservation populations in areas of refugia. To date, however, there are few examples of successful conservation-based introductions. Many attempts fail to establish new populations—in part because environmental factors that might influence success are inadequately evaluated before the translocation is implemented. We developed a framework to assess the feasibility of rescuing threatened fish populations through translocation into historically unoccupied stream and lake habitats. The suitability of potential introduction sites was evaluated based on four major components: the recipient habitat, recipient community, donor population, and future threats. Specific questions were then developed to evaluate each major component. The final assessment was based on a scoring system that addressed each question by using criteria developed from characteristics representative of highly suitable habitats and populations. This framework was used to evaluate the proposed within-drainage translocation of three Bull Trout Salvelinus confluentus populations in Glacier National Park, Montana. Our results indicated that within-drainage translocation is a feasible strategy for conserving locally adapted populations of Bull Trout through the creation of new areas of refugia in Glacier National Park. The framework provides a flexible platform that can help managers make informed decisions for moving threatened fishes into new areas of refugia for conservation and recovery programs.

  5. Bull Trout (Salvelinus Confluentus) Population and Habitat Surveys in the McKenzie and Middle Fork Willamette Basins, 2000 Annual Report.

    SciTech Connect

    Taylor, Greg

    2000-11-28

    Prior to 1978, Dolly Varden Salvelinus malma were classified into an anadromous and interior form. Cavender (1978) classified the interior form as a distinct species, Salvelinus confluentus, the bull trout. Bull trout are large char weighing up to 18 kg and growing to over one meter in length (Goetz 1989). They are distinguished by a broad flat head, large downward curving maxillaries that extend beyond the eye, a well developed fleshy knob and a notch in the lower terminus of the snout, and light colored spots normally smaller than the pupil of the eye (Cavender 1978). Bull trout are found throughout northwestern North America from lat. 41{sup o}N to lat. 60{sup o}N. In Oregon, bull trout were once distributed throughout 12 basins in the Klamath and Columbia River systems including the Clackamas, Santiam, McKenzie and Middle Fork Willamette sub-basins west of the Cascades (Buchanan et al. 1997). However, it is believed bull trout have been extirpated from west of the Cascades with the exception of the McKenzie sub-basin. Before 1963, bull trout in the McKenzie sub-basin were a contiguous population from the mouth to Tamolitch Falls. Following the construction of Cougar and Trail Bridge Reservoirs there are three isolated populations: (1) mainstem McKenzie and tributaries from the mouth to Trail Bridge Reservoir. (2) mainstem McKenzie and tributaries above Trail Bridge Reservoir to Tamolitch Falls. (3) South Fork McKenzie and tributaries above Cougar Reservoir. The study area includes the three aforementioned McKenzie populations, and the Middle Fork Willamette and tributaries above Hills Creek Reservoir. We monitored bull trout populations in the McKenzie and Middle Fork Willamette basins using a combination of sampling techniques including: spawning surveys, standard pool counts, juvenile trapping, radio tracking, electronic fish counters, and a modified Hankin and Reeves protocol to estimate juvenile abundance and density. In addition, we continued to

  6. Temperature-mediated differences in bacterial kidney disease expression and survival in Renibacterium salmoninarum-challenged bull trout and other salmonids

    USGS Publications Warehouse

    Jones, D.T.; Moffitt, C.M.; Peters, K.K.

    2007-01-01

    Resource managers considering restoration and reconnection of watersheds to protect and enhance threatened populations of bull trout Salvelinus confluentus have little information about the consequences of bacterial kidney disease (BKD) caused by Renibacterium salmoninarum. To better understand the response of bull trout to R. salmoninarum challenge, we conducted several laboratory experiments at two water temperatures. The extent, severity, and lethality of BKD in bull trout were compared with those of similarly challenged lake trout S. namaycush, Arctic char S. alpinus, Chinook salmon Oncorhynchus tshawytscha, and rainbow trout O. mykiss. The lethal dose of bacterial cells necessary to induce 50% mortality (LD50) was 10-fold lower at the 15??C challenge than at the 9??C challenge. Of the species tested, bull trout were relatively resistant to BKD, Arctic char were the most susceptible among Salvelinus species, and Chinook salmon were the most susceptible among Oncorhynchus species tested. Mean time to death was more rapid for all fish tested at 15??C than for fish challenged at 9??C. These results suggest that infection of bull trout with BKD likely poses a low risk to successful restoration of threatened populations. ?? Copyright by the American Fisheries Society 2007.

  7. Evaluation of the Life History of Native Salmonids in the Malheur River Basin; Cooperative Bull Trout/Redband Trout Research Project, 2002-2003 Annual Report.

    SciTech Connect

    Miller, Alan; Soupir, Jim; Schwabe, Lawrence

    2003-08-01

    The Malheur River is a 306-kilometer tributary to the Snake River, which drains 12,950 square kilometers. The Malheur River originates in the Blue Mountains and flows into the Snake River near Ontario, Oregon. The climate of the basin is characterized by hot dry summers, occasionally exceeding 38 C, and cold winters that may drop below -29 C. Average annual precipitation is 30 centimeters in the lower reaches. Wooded areas consist primarily of mixed fir and pine forest in the higher elevations. Sagebrush and grass communities dominate the flora in the lower elevations. Efforts to document salmonid life histories, water quality, and habitat conditions have continued in fiscal year 2002. Bull trout Salvelinus confluentus are considered to be cold water species and are temperature-dependant. Due to the interest of bull trout from various state and Federal agencies, a workgroup was formed to develop project objectives related to bull trout. Table 1 lists individuals that participated in the 2002 work group. This report will reflect work completed during the Bonneville Power Administration contract period starting April 1, 2002, and ending March 31, 2003. All tasks were conducted within this timeframe, and a more detailed timeframe may be referred to in each individual report.

  8. Bull Trout (Salvelinus Confluentus) Population and Habitat Surveys in the McKenzie and Middle Fork Willamette Basins, 2001 Annual Report.

    SciTech Connect

    Taylor, Greg

    2003-02-01

    Prior to 1978, bull trout were commonly known as dolly varden (Salvelinus malma) and were classified into an anadromous and interior form. Cavender (1978) described the interior form as a distinct species, classifying it as Salvelinus confluentus, the bull trout. Bull trout are large char weighing up to 18 kg and growing to over one meter in length (Goetz 1994). They are distinguished by a broad flat head, large downward curving maxillaries that extend beyond the eye, a fleshy knob and a notch in the lower terminus of the snout, and light colored spots normally smaller than the pupil of the eye (Cavender 1978). Bull trout are found throughout northwestern North America from latitude 41{sup o}N to 60{sup o}N. In Oregon, bull trout were once distributed throughout 12 basins in the Klamath and Columbia River systems including the Clackamas, Santiam, McKenzie and Middle Fork Willamette subbasins west of the Cascades (Buchanan et al. 1997). However, it is likely that bull trout have been extirpated from west of the Cascades with the exception of the McKenzie sub-basin. McKenzie River bull trout were a contiguous population from the mouth to Tamolitch Falls prior to 1963. Three populations were isolated following the construction of Cougar and Trail Bridge Reservoirs which include the mainstem McKenzie and tributaries from the mouth to Trail Bridge Reservoir, mainstem McKenzie and tributaries above Trail Bridge Reservoir to Tamolitch Falls, and the South Fork McKenzie and tributaries above Cougar Reservoir. On June 10, 1998 the U.S. Fish and Wildlife Service (USFWS) listed the Columbia River bull trout population segment as Threatened under the federal Endangered Species Act and Buchanan et al. (1997) listed the bull trout population in the mainstem McKenzie as ''of special concern'', the South Fork McKenzie population as ''high risk of extinction,'' and the population above Trail Bridge Reservoir as ''high risk of extinction.'' Bull trout in the Middle Fork Willamette

  9. Mitochondrial DNA variation in bull trout (Salvelinus confluentus) from northwestern North America: implications for zoogeography and conservation.

    PubMed

    Taylor, E B; Pollard, S; Louie, D

    1999-07-01

    Bull trout, Salvelinus confluentus (Salmonidae), are distributed in northwestern North America from Nevada to Yukon Territory, largely in interior drainages. The species is of conservation concern owing to declines in abundance, particularly in southern portions of its range. To investigate phylogenetic structure within bull trout that might form the basis for the delineation of major conservation units, we conducted a mitochondrial DNA (mtDNA) survey in bull trout from throughout its range. Restriction fragment length polymorphism (RFLP) analysis of four segments of the mtDNA genome with 11 restriction enzymes resolved 21 composite haplotypes that differed by an average of 0.5% in sequence. One group of haplotypes predominated in 'coastal' areas (west of the coastal mountain ranges) while another predominated in 'interior' regions (east of the coastal mountains). The two putative lineages differed by 0.8% in sequence and were also resolved by sequencing a portion of the ND1 gene in a representative of each RFLP haplotype. Significant variation existed within individual sample sites (12% of total variation) and among sites within major geographical regions (33%), but most variation (55%) was associated with differences between coastal and interior regions. We concluded that: (i) bull trout are subdivided into coastal and interior lineages; (ii) this subdivision reflects recent historical isolation in two refugia south of the Cordilleran ice sheet during the Pleistocene: the Chehalis and Columbia refugia; and (iii) most of the molecular variation resides at the interpopulation and inter-region levels. Conservation efforts, therefore, should focus on maintaining as many populations as possible across as many geographical regions as possible within both coastal and interior lineages.

  10. Multi-scale geomorphic and hydrogeologic influences on bull trout (Salvelinus confluentus) spawning habitat in headwater streams

    NASA Astrophysics Data System (ADS)

    Bean, J. R.; Wilcox, A. C.; Woessner, W. W.; Muhlfeld, C.

    2013-12-01

    We investigated multi-scale hydrogeomorphic influences on the distribution and abundance of bull trout (Salvelinus confluentus) spawning in snowmelt- dominated streams of the upper Flathead River basin, northwestern Montana. Bull trout redds were primarily found in unconfined alluvial valley reaches (74%), which were strongly influenced by hyporheic and groundwater-stream water exchange. A considerable proportion of redds (26%), however, were patchily distributed in confined valley reaches. Among all reaches and subreaches, the abundance of redds increased with increased bankfull dimensionless shear stress and decreased with reach-average streambed grain size (p < 0.05). Within these selected reaches and subreaches, redd occurrence tended to be associated with the finest available textural facies (i.e., gravel and small cobble substrates) in concave-up bedforms with downwelling intragravel flows. Streambed temperatures tracked stream water diurnal temperature cycles to a depth of at least 25 cm. Groundwater provided substantial thermal moderation of stream water for several high-density spawning reaches. Our spawning gravel competence results indicate that bull trout select spawning areas that are potentially susceptible to flooding-induced scour during the fall and winter incubation period.

  11. Impacts and pathways of mine contaminants to bull trout (Salvelinus confluentus) in an Idaho watershed.

    PubMed

    Kiser, Tim; Hansen, James; Kennedy, Brian

    2010-08-01

    Metals contamination from mining activities is a persistent problem affecting aquatic ecosystems throughout mining districts in the western USA. The Gold Creek drainage in northern Idaho has a history of mining within its headwaters and contains elevated sediment concentrations of As, Cd, Cu, Pb, and Zn. To determine system-wide impacts of increased metals, we measured concentrations of metals in water, sediment, and benthic macroinvertebrate tissues and related them to whole-body fish tissues and histopathological alterations in native salmonids. Water concentrations were higher than those in reference areas, but were below water quality criteria for protection of aquatic biota for most of the study area. Sediment and benthic macroinvertebrate tissue concentrations for all metals were significantly higher at all sites compared with the reference site. Fish tissues were significantly higher for all metals below mine sites compared with the reference site, but only Cd and Pb were higher in fish tissues in the furthest downstream reach in the Gold Creek Delta. Metals concentrations in benthic macroinvertebrate tissues and fish tissues were strongly correlated, suggesting a transfer of metals through a dietary pathway. The concentrations within sediments and biota were similar to those reported in other studies in which adverse effects to salmonids occurred. We observed histopathological changes in livers of bull trout, including inflammation, necrosis, and pleomorphism. Our study is consistent with other work in which sediment-driven exposure can transfer up the food chain and may cause adverse impacts to higher organisms.

  12. Assessing the feasibility of native fish reintroductions: a framework applied to threatened bull trout

    USGS Publications Warehouse

    Dunham, Jason B.; Gallo, Kirsten; Shively, Dan; Allen, Chris; Goehring, Brad

    2011-01-01

    Translocations to recover native fishes have resulted in mixed success. One reason for the failure of these actions is inadequate assessments of their feasibility prior to implementation. Here, we provide a framework developed to assess the feasibility of one type of translocation-reintroduction. The framework was founded on two simple components of feasibility: the potential for recipient habitats to support a reintroduction and the potential of available donor populations to support a reintroduction. Within each component, we developed a series of key questions. The final assessment was based on a scoring system that incorporated consideration of uncertainty in available information. The result was a simple yet transparent system for assessing reintroduction feasibility that can be rapidly applied in practice. We applied this assessment framework to the potential reintroduction of threatened bull trout Salvelinus confluentus into the Clackamas River, Oregon. In this case, the assessment suggested that the degree of feasibility for reintroduction was high based on the potential of recipient habitats and available donor populations. The assessment did not provide a comprehensive treatment of all possible factors that would drive an actual decision to implement a reintroduction,

  13. Evaluation of the Life History of Native Salmonids in the Malheur River Basin; Cooperative Bull Trout/Redband Trout Research Project, 2000-2001 Annual Report.

    SciTech Connect

    Gonzales, Dan; Schwabe, Lawrence; Wenick, Jess

    2001-08-01

    The Malheur basin lies within southeastern Oregon. The Malheur River is a tributary to the Snake River, entering at about River Kilometer (RK) 595. The hydrological drainage area of the Malheur River is approximately 12,950 km{sup 2} and is roughly 306 km in length. The headwaters of the Malheur River originate in the Blue Mountains at elevations of 6,500 to 7,500 feet, and drops to an elevation of 2000 feet at the confluence with the Snake River near Ontario, Oregon. The climate of the Malheur basin is characterized by hot dry summers, occasionally exceeding 38 C and cold winters that may drop below -29 C. Average annual precipitation is 300 centimeters and ranges from 100 centimeters in the upper mountains to less than 25 centimeters in the lower reaches (Gonzalez 1999). Wooded areas consist primarily of mixed fir and pine forest in the higher elevations. Sagebrush and grass communities dominate the flora in the lower elevations. Efforts to document salmonid life histories, water quality, and habitat conditions have continued in fiscal year 2000. The Burns Paiute Tribe (BPT), United States Forest Service (USFS), and Oregon Department of Fish and Wildlife (ODFW), have been working cooperatively to achieve this common goal. Bull trout ''Salvenlinus confluentus'' have specific environmental requirements and complex life histories making them especially susceptible to human activities that alter their habitat (Howell and Buchanan 1992). Bull trout are considered to be a cold-water species and are temperature dependent. This presents a challenge for managers, biologists, and private landowners in the Malheur basin. Because of the listing of bull trout under the Endangered Species Act as threatened and the current health of the landscape, a workgroup was formed to develop project objectives related to bull trout. This report will reflect work completed during the Bonneville Power contract period starting 1 April 2000 and ending 31 March 2001. The study area will

  14. Using accelerated life testing procedures to compare the relative sensitivity of rainbow trout and the federally listed threatened bull trout to three commonly used rangeland herbicides (picloram, 2,4-D, and clopyralid)

    USGS Publications Warehouse

    Fairchild, J.F.; Allert, A.; Sappington, L.S.; Nelson, K.J.; Valle, J.

    2008-01-01

    We conducted 96-h static acute toxicity studies to evaluate the relative sensitivity of juveniles of the threatened bull trout (Salvelinus confluentus) and the standard cold-water surrogate rainbow trout (Onchorhyncus mykiss) to three rangeland herbicides commonly used for controlling invasive weeds in the northwestern United States. Relative species sensitivity was compared using three procedures: standard acute toxicity testing, fractional estimates of lethal concentrations, and accelerated life testing chronic estimation procedures. The acutely lethal concentrations (ALC) resulting in 50% mortality at 96 h (96-h ALC50s) were determined using linear regression and indicated that the three herbicides were toxic in the order of picloram acid > 2,4-D acid > clopyralid acid. The 96-h ALC50 values for rainbow trout were as follows: picloram, 41 mg/L; 2.4-D, 707 mg/L; and clopyralid, 700 mg/L. The 96-h ALC50 values for bull trout were as follows: picloram, 24 mg/L; 2.4-D, 398 mg/L; and clopyralid, 802 mg/L. Fractional estimates of safe concentrations, based on 5% of the 96-h ALC50, were conservative (overestimated toxicity) of regression-derived 96-h ALC5 values by an order of magnitude. Accelerated life testing procedures were used to estimate chronic lethal concentrations (CLC) resulting in 1% mortality at 30 d (30-d CLC1) for the three herbicides: picloram (1 mg/L rainbow trout, 5 mg/L bull trout), 2,4-D (56 mg/L rainbow trout, 84 mg/L bull trout), and clopyralid (477 mg/L rainbow trout; 552 mg/L bull trout). Collectively, the results indicated that the standard surrogate rainbow trout is similar in sensitivity to bull trout. Accelerated life testing procedures provided cost-effective, statistically defensible methods for estimating safe chronic concentrations (30-d CLC1s) of herbicides from acute toxicity data because they use statistical models based on the entire mortality:concentration: time data matrix. ?? 2008 SETAC.

  15. Using accelerated life testing procedures to compare the relative sensitivity of rainbow trout and the federally listed threatened bull trout to three commonly used rangeland herbicides (picloram, 2,4-D, and clopyralid).

    PubMed

    Fairchild, James F; Allert, Ann; Sappington, Linda S; Nelson, Karen J; Valle, Janet

    2008-03-01

    We conducted 96-h static acute toxicity studies to evaluate the relative sensitivity of juveniles of the threatened bull trout (Salvelinus confluentus) and the standard cold-water surrogate rainbow trout (Onchorhyncus mykiss) to three rangeland herbicides commonly used for controlling invasive weeds in the northwestern United States. Relative species sensitivity was compared using three procedures: standard acute toxicity testing, fractional estimates of lethal concentrations, and accelerated life testing chronic estimation procedures. The acutely lethal concentrations (ALC) resulting in 50% mortality at 96 h (96-h ALC50s) were determined using linear regression and indicated that the three herbicides were toxic in the order of picloram acid > 2,4-D acid > clopyralid acid. The 96-h ALC50 values for rainbow trout were as follows: picloram, 41 mg/L; 2.4-D, 707 mg/L; and clopyralid, 700 mg/L. The 96-h ALC50 values for bull trout were as follows: picloram, 24 mg/L; 2.4-D, 398 mg/L; and clopyralid, 802 mg/L. Fractional estimates of safe concentrations, based on 5% of the 96-h ALC50, were conservative (overestimated toxicity) of regression-derived 96-h ALC5 values by an order of magnitude. Accelerated life testing procedures were used to estimate chronic lethal concentrations (CLC) resulting in 1% mortality at 30 d (30-d CLC1) for the three herbicides: picloram (1 mg/L rainbow trout, 5 mg/L bull trout), 2,4-D (56 mg/L rainbow trout, 84 mg/L bull trout), and clopyralid (477 mg/L rainbow trout; 552 mg/L bull trout). Collectively, the results indicated that the standard surrogate rainbow trout is similar in sensitivity to bull trout. Accelerated life testing procedures provided cost-effective, statistically defensible methods for estimating safe chronic concentrations (30-d CLC1s) of herbicides from acute toxicity data because they use statistical models based on the entire mortality:concentration:time data matrix.

  16. Scales of Stream Disturbance Patterns and Population Structure in Bull Trout

    NASA Astrophysics Data System (ADS)

    Luce, C. H.; Rieman, B. E.; Dunham, J. B.

    2005-05-01

    Ecological theory proposes that the geometry and dynamics of suitable habitats are important predictors for the persistence of a population or metapopulation. A key finding supporting a metapopulation-like conceptualization of extinction and colonization in fragmented salmonid populations is that individuals of particular species are more likely to be absent from small patches of suitable habitat than from large patches. Extinctions from small patches occur for a few reasons that can be roughly classed as physical catastrophic causes (e.g. a major channel reorganizing event) or as biological small-population effects related to genetics and demographics. One important question with implications for land management is how strong of a role physical disturbances play in determining presence and absence of a species within a patch. If disturbance plays a key role in structuring populations, then we would expect to observe two patterns. First the spatial scale of disturbance should be on the order of the size of patches that are commonly unoccupied. The second prediction would be that the spatial scale of genetic variability should show strong gene flow at scales smaller than the scale of disturbance. We examined aerial photography over the last 40 years in central Idaho to measure the scale of stream disturbance patches. The scale of stream disturbances was on the same order of magnitude as the divide between commonly occupied and unoccupied patches, and was smaller than scales of high gene flow among bull trout populations, failing to reject the possibility that disturbance plays an important role in structuring populations in this basin. Management for persistence of the species must consider both the likelihood of decreased habitat patch sizes and increased disturbance scales with global warming. Knowing disturbance patch scales and how disturbance operates to structure populations can be used to consider a disturbance based paradigm for management of sensitive

  17. Movement of bull trout in the upper Jarbidge River watershed, Idaho and Nevada, 2008-09--A supplement to Open-File Report 2010-1033

    USGS Publications Warehouse

    Munz, Carrie S.; Allen, M. Brady; Connolly, Patrick J.

    2011-01-01

    We monitored bull trout (Salvelinus confluentus) in 2008 and 2009 as a continuation of our work in 2006 and 2007, which involved the tagging of 1,536 bull trout with passive integrated transponder (PIT) tags in the East Fork Jarbidge River and West Fork Jarbidge River and their tributaries in northeastern Nevada and southern Idaho. We installed PIT tag interrogation systems (PTISs) at established locations soon after ice-out, and maintained the PTISs in order to collect information on bull trout movements through December of each year. We observed a marked increase of movement in 2008 and 2009. Bull trout tagged in the uppermost portions of the East Fork Jarbidge River at altitudes greater than 2,100 meters moved to the confluence of the East Fork Jarbidge River and West Fork Jarbidge River in summer and autumn. Ten bull trout tagged upstream of the confluence of Pine Creek and the West Fork Jarbidge River moved downstream and then upstream in the East Fork Jarbidge River, and then past the PTIS at Murphy Hot Springs (river kilometer [rkm] 4.1). Two of these fish ascended Dave Creek, a tributary of the East Fork Jarbidge River, past the PTIS at rkm 0.4. One bull trout that was tagged at rkm 11 in Dave Creek on June 28, 2007 moved downstream to the confluence of the East Fork Jarbidge River and West Fork Jarbidge River (rkm 0) on July 28, 2007, and it was then detected in the West Fork Jarbidge River moving past our PTIS at rkm 15 on May 4, 2008. Combined, the extent and types of bull trout movements observed indicated that the primarily age-1 and age-2 bull trout that we tagged in 2006 and 2007 showed increased movement with age and evidence of a substantial amount of fluvial life history. The movements suggest strong connectivity between spawning areas and downstream mainstem areas, as well as between the East Fork Jarbidge River and West Fork Jarbidge River.

  18. Kootenai River Fisheries Investigations : Rainbow Trout Recruitment : Period Covered: 1997.

    SciTech Connect

    Downs, Chris

    1999-02-02

    The objective of this study was to determine if juvenile production is limiting the population of rainbow trout Oncorbynchus mykiss in the Idaho reach of the Kootenai River. We used snorkeling and electrofishing techniques to estimate juvenile rainbow trout abundance in, and outmigration from, the Deep, Boulder, and Myrtle creek drainages in Idaho. The total population estimates for the three drainages estimated in 1997 were 30,023; 763; and 235; respectively. A rotary-screw trap was utilized to capture juvenile outmigrants for quantification of age at outmigration and total outmigration from the Deep Creek drainage to the Kootenai River. The total outmigrant estimate for 1997 from the Deep Creek drainage was 38,206 juvenile rainbow trout. Age determination based largely on scales suggests that most juvenile rainbow trout outmigration from the Deep Creek drainage occurs at age-l, during the spring runoff period. Forty-three adult rainbow trout captured in the Deep Creek drainage were tagged with $10.00 reward T-bar anchor tags in 1997. A total of three of these fish were harvested, all in Kootenay Lake, British Columbia. This suggests the possibility of an adfluvial component in the spawning population of the Deep Creek drainage.

  19. The effects of long-term cadmium exposure on the growth and survival of juvenile bull trout (Salvelinus confluentus).

    PubMed

    Hansen, J A; Welsh, P G; Lipton, J; Suedkamp, M J

    2002-08-01

    Bull trout (Salvelinus confluentus) have been listed recently as threatened in the United States under the federal Endangered Species Act. This species currently resides, or historically resided, in several waterways that either are impacted or are under threat of impact from metals mining activities. We conducted a 55-day sub-chronic (i.e. sublethal) cadmium (Cd) exposure in water at 30 mg l(-1) (as CaCO(3)) hardness, pH 7.5, and 8 degrees C. Exposures were conducted using six replicate exposure tanks for each of the six treatments (five Cd concentrations and one control). Measured Cd concentrations were <0.013 (control), 0.052, 0.089, 0.197, 0.383, and 0.786 microg Cd l(-1). Exposure to 0.786 microg Cd l(-1) caused increased mortality (37%) and reduced growth (28% reduction in weight change) in fish exposed for 55 days. All Cd exposure concentrations caused significant whole body accumulation of Cd compared with controls. Our results indicate that even though fish are significantly accumulating Cd in each non-control treatment, growth reductions in bull trout occurred only at Cd concentrations that also caused significant mortality. The Cd concentration that reduced growth and survival in this long-term exposure (0.786 microg Cd l(-1)) is greater than the recently-revised US federal aquatic life criteria (ALC) value for the corresponding hardness concentration (ALC=0.62 microg Cd l(-1) for acute effects and 0.11 microg Cd l(-1) for chronic effects).

  20. Observer error structure in bull trout redd counts in Montana streams: Implications for inference on true redd numbers

    USGS Publications Warehouse

    Muhlfeld, Clint C.; Taper, Mark L.; Staples, David F.; Shepard, Bradley B.

    2006-01-01

    Despite the widespread use of redd counts to monitor trends in salmonid populations, few studies have evaluated the uncertainties in observed counts. We assessed the variability in redd counts for migratory bull trout Salvelinus confluentus among experienced observers in Lion and Goat creeks, which are tributaries to the Swan River, Montana. We documented substantially lower observer variability in bull trout redd counts than did previous studies. Observer counts ranged from 78% to 107% of our best estimates of true redd numbers in Lion Creek and from 90% to 130% of our best estimates in Goat Creek. Observers made both errors of omission and errors of false identification, and we modeled this combination by use of a binomial probability of detection and a Poisson count distribution of false identifications. Redd detection probabilities were high (mean = 83%) and exhibited no significant variation among observers (SD = 8%). We applied this error structure to annual redd counts in the Swan River basin (1982–2004) to correct for observer error and thus derived more accurate estimates of redd numbers and associated confidence intervals. Our results indicate that bias in redd counts can be reduced if experienced observers are used to conduct annual redd counts. Future studies should assess both sources of observer error to increase the validity of using redd counts for inferring true redd numbers in different basins. This information will help fisheries biologists to more precisely monitor population trends, identify recovery and extinction thresholds for conservation and recovery programs, ascertain and predict how management actions influence distribution and abundance, and examine effects of recovery and restoration activities.

  1. Evidence of climate-induced range contractions in bull trout Salvelinus confluentus in a Rocky Mountain watershed, U.S.A.

    PubMed

    Eby, Lisa A; Helmy, Olga; Holsinger, Lisa M; Young, Michael K

    2014-01-01

    Many freshwater fish species are considered vulnerable to stream temperature warming associated with climate change because they are ectothermic, yet there are surprisingly few studies documenting changes in distributions. Streams and rivers in the U.S. Rocky Mountains have been warming for several decades. At the same time these systems have been experiencing an increase in the severity and frequency of wildfires, which often results in habitat changes including increased water temperatures. We resampled 74 sites across a Rocky Mountain watershed 17 to 20 years after initial samples to determine whether there were trends in bull trout occurrence associated with temperature, wildfire, or other habitat variables. We found that site abandonment probabilities (0.36) were significantly higher than colonization probabilities (0.13), which indicated a reduction in the number of occupied sites. Site abandonment probabilities were greater at low elevations with warm temperatures. Other covariates, such as the presence of wildfire, nonnative brook trout, proximity to areas with many adults, and various stream habitat descriptors, were not associated with changes in probability of occupancy. Higher abandonment probabilities at low elevation for bull trout provide initial evidence validating the predictions made by bioclimatic models that bull trout populations will retreat to higher, cooler thermal refuges as water temperatures increase. The geographic breadth of these declines across the region is unknown but the approach of revisiting historical sites using an occupancy framework provides a useful template for additional assessments.

  2. Evidence of Climate-Induced Range Contractions in Bull Trout Salvelinus confluentus in a Rocky Mountain Watershed, U.S.A

    PubMed Central

    Eby, Lisa A.; Helmy, Olga; Holsinger, Lisa M.; Young, Michael K.

    2014-01-01

    Many freshwater fish species are considered vulnerable to stream temperature warming associated with climate change because they are ectothermic, yet there are surprisingly few studies documenting changes in distributions. Streams and rivers in the U.S. Rocky Mountains have been warming for several decades. At the same time these systems have been experiencing an increase in the severity and frequency of wildfires, which often results in habitat changes including increased water temperatures. We resampled 74 sites across a Rocky Mountain watershed 17 to 20 years after initial samples to determine whether there were trends in bull trout occurrence associated with temperature, wildfire, or other habitat variables. We found that site abandonment probabilities (0.36) were significantly higher than colonization probabilities (0.13), which indicated a reduction in the number of occupied sites. Site abandonment probabilities were greater at low elevations with warm temperatures. Other covariates, such as the presence of wildfire, nonnative brook trout, proximity to areas with many adults, and various stream habitat descriptors, were not associated with changes in probability of occupancy. Higher abandonment probabilities at low elevation for bull trout provide initial evidence validating the predictions made by bioclimatic models that bull trout populations will retreat to higher, cooler thermal refuges as water temperatures increase. The geographic breadth of these declines across the region is unknown but the approach of revisiting historical sites using an occupancy framework provides a useful template for additional assessments. PMID:24897341

  3. Population recovery and natural recruitment of lake trout at Gull Island Shoal, Lake Superior, 1964-1992

    USGS Publications Warehouse

    Schram, Stephen T.; Selgeby, James H.; Bronte, Charles R.; Swanson, Bruce L.

    1995-01-01

    We documented an increase in the abundance of wild lake trout (Salvelinus namaycush) at Gull Island Shoal in western Lake Superior and examined the relationship between parental-stock size and recruitment of age-0 fish in 1964–1992. Abundance of adult wild female lake trout and densities of age-0 fish both increased during the 28-year period. A significant positive, linear relationship (P = 0.0002) was found between the abundance of wild females on the spawning reef in the fall and density of age-0 lake trout on adjacent nursery grounds in August and September of the following year. The abundance of hatchery-origin females did not explain significant amounts (P = 0.107) of variation in recruitment. We concluded that most recruitment in 1965–1992 was the result of natural reproduction of wild females. After 28 years of recovery the Gull Island Shoal lake trout population appears to have additional capacity to increase because the stock-recruitment relationship is still linear. Therefore, restoration periods on the order of 30 years may be needed for other lake trout populations in the Great Lakes. We recommend that the refuge established to protect this population be maintained to allow further study of the relationship between parental stock and recruitment, and to provide a major source of recruitment to the lake trout population in the surrounding waters

  4. Combining inferences from models of capture efficiency, detectability, and suitable habitat to classify landscapes for conservation of threatened bull trout

    USGS Publications Warehouse

    Peterson, J.; Dunham, J.B.

    2003-01-01

    Effective conservation efforts for at-risk species require knowledge of the locations of existing populations. Species presence can be estimated directly by conducting field-sampling surveys or alternatively by developing predictive models. Direct surveys can be expensive and inefficient, particularly for rare and difficult-to-sample species, and models of species presence may produce biased predictions. We present a Bayesian approach that combines sampling and model-based inferences for estimating species presence. The accuracy and cost-effectiveness of this approach were compared to those of sampling surveys and predictive models for estimating the presence of the threatened bull trout ( Salvelinus confluentus ) via simulation with existing models and empirical sampling data. Simulations indicated that a sampling-only approach would be the most effective and would result in the lowest presence and absence misclassification error rates for three thresholds of detection probability. When sampling effort was considered, however, the combined approach resulted in the lowest error rates per unit of sampling effort. Hence, lower probability-of-detection thresholds can be specified with the combined approach, resulting in lower misclassification error rates and improved cost-effectiveness.

  5. Genetic assessment of strain-specific sources of lake trout recruitment in the Great Lakes

    USGS Publications Warehouse

    Page, Kevin S.; Scribner, Kim T.; Bennett, Kristine R.; Garzel, Laura M.; Burnham-Curtis, Mary K.

    2003-01-01

    Populations of wild lake trout Salvelinus namaycush have been extirpated from nearly all their historical habitats across the Great Lakes. Efforts to restore self-sustaining lake trout populations in U.S. waters have emphasized the stocking of coded-wire-tagged juveniles from six hatchery strains (Seneca Lake, Lewis Lake, Green Lake, Apostle Islands, Isle Royale, and Marquette) into vacant habitats. Strain-specific stocking success has historically been based on estimates of the survival and catch rates of coded-wire-tagged adults returning to spawning sites. However, traditional marking methods and estimates of relative strain abundance provide no means of assessing strain fitness (i.e., the realized contributions to natural recruitment) except by assuming that young-of-the-year production is proportional to adult spawner abundance. We used microsatellite genetic data collected from six hatchery strains with likelihood-based individual assignment tests (IA) and mixed-stock analysis (MSA) to identify the strain composition of young of the year recruited each year. We show that strain classifications based on IA and MSA were concordant and that the accuracy of both methods varied based on strain composition. Analyses of young-of-the-year lake trout samples from Little Traverse Bay (Lake Michigan) and Six Fathom Bank (Lake Huron) revealed that strain contributions differed significantly from estimates of the strain composition of adults returning to spawning reefs. The Seneca Lake strain contributed the majority of juveniles produced on Six Fathom Bank and more young of the year than expected within Little Traverse Bay. Microsatellite markers provided a method for accurately classifying the lake trout hatchery strains used for restoration efforts in the Great Lakes and for assessment of strain-specific reproductive success.

  6. Kootenai River Fisheries Investigations; Chapter 3 : Mainstem Habitat Use and Recruitment Estimates of Rainbow Trout, 1996 Annual Report.

    SciTech Connect

    Fredericks, James P.; Hendricks, Steve

    1997-09-01

    The objective of this study was to determine if recruitment is limiting the population of rainbow trout Oncorhynchus mykiss in the mainstem Kootenai River. The authors used snorkeling and electrofishing techniques to estimate juvenile rainbow trout density and total numbers in Idaho tributaries, and they trapped juvenile outmigrants to identify the age at which juvenile trout migrate from tributaries to the Kootenai River. The authors radio and reward-tagged post-spawn adult rainbow trout captured in Deep Creek to identify river reach and habitat used by those fish spawning and rearing in the Deep Creek drainage. They also conducted redd surveys in the Kootenai River to determine the extent of mainstem spawning. Based on the amount of available habitat and juvenile rainbow trout densities, the Deep Creek drainage was the most important area for juvenile production. Population estimates of age 0, age 1+, and age 2+ rainbow trout indicated moderate to high densities in several streams in the Deep Creek drainage whereas other streams, such as Deep Creek, had very low densities of juvenile trout. The total number of age 0, age 1+, and age 2+ rainbow trout in Deep Creek drainage in 1996 was estimated to be 63,743, 12,095, and 3,095, respectively. Radio telemetry efforts were hindered by the limited range of the transmitters, but movements of a radio-tagged trout and a returned reward tag indicated that at least a portion of the trout utilizing the Deep Creek drainage migrated downriver from the mouth of Deep Creek to the meandering section of river. They found no evidence of mainstem spawning by rainbow trout, but redd counting efforts were hindered by high flows from mid-April through June.

  7. Seasonal movement and distribution of fluvial adult bull trout in selected watersheds in the mid-Columbia River and Snake River basins.

    PubMed

    Starcevich, Steven J; Howell, Philip J; Jacobs, Steven E; Sankovich, Paul M

    2012-01-01

    From 1997 to 2004, we used radio telemetry to investigate movement and distribution patterns of 206 adult fluvial bull trout (mean, 449 mm FL) from watersheds representing a wide range of habitat conditions in northeastern Oregon and southwestern Washington, a region for which there was little previous information about this species. Migrations between spawning and wintering locations were longest for fish from the Imnaha River (median, 89 km) and three Grande Ronde River tributaries, the Wenaha (56 km) and Lostine (41 km) rivers and Lookingglass Creek (47 km). Shorter migrations were observed in the John Day (8 km), Walla Walla (20 km) and Umatilla river (22 km) systems, where relatively extensive human alterations of the riverscape have been reported. From November through May, fish displayed station-keeping behavior within a narrow range (basin medians, 0.5-6.2 km). Prespawning migrations began after snowmelt-driven peak discharge and coincided with declining flows. Most postspawning migrations began by late September. Migration rates of individuals ranged from 0.1 to 10.7 km/day. Adults migrated to spawning grounds in consecutive years and displayed strong fidelity to previous spawning areas and winter locations. In the Grande Ronde River basin, most fish displayed an unusual fluvial pattern: After exiting the spawning tributary and entering a main stem river, individuals moved upstream to wintering habitat, often a substantial distance (maximum, 49 km). Our work provides additional evidence of a strong migratory capacity in fluvial bull trout, but the short migrations we observed suggest adult fluvial migration may be restricted in basins with substantial anthropogenic habitat alteration. More research into bull trout ecology in large river habitats is needed to improve our understanding of how adults establish migration patterns, what factors influence adult spatial distribution in winter, and how managers can protect and enhance fluvial populations.

  8. Relation between Streamflow of Swiftcurrent Creek, Montana, and the Geometry of Passage for Bull Trout (Salvelinus confluentus)

    USGS Publications Warehouse

    Auble, Gregor T.; Holmquist-Johnson, Christopher L.; Mogen, Jim T.; Kaeding, Lynn R.; Bowen, Zachary H.

    2009-01-01

    Operation of Sherburne Dam in northcentral Montana has typically reduced winter streamflow in Swiftcurrent Creek downstream of the dam and resulted in passage limitations for bull trout (Salvelinus confluentus). We defined an empirical relation between discharge in Swiftcurrent Creek between Sherburne Dam and the downstream confluence with Boulder Creek and fish passage geometry by considering how the cross-sectional area of water changed as a function of discharge at a set of cross sections likely to limit fish passage. With a minimum passage window of 15 x 45 cm, passage at the cross sections increased strongly with discharge over the range of 1.2 to 24 cfs. Most cross sections did not satisfy the minimum criteria at 1.2 cfs, 25 percent had no passage at 12.7 cfs, whereas at 24 cfs all but one of 26 cross sections had some passage and 90 percent had more than 3 m of width satisfying the minimum criteria. Sensitivity analysis suggests that the overall results are not highly dependent on exact dimensions of the minimum passage window. Combining these results with estimates of natural streamflow in the study reach further suggests that natural streamflow provided adequate passage at some times in most months and locations in the study reach, although not for all individual days and locations. Limitations of our analysis include assumptions about minimum passage geometry, measurement error, limitations of the cross-sectional model we used to characterize passage, the relation of Sherburne Dam releases to streamflow in the downstream study reach in the presence of ephemeral accretions, and the relation of passage geometry as we have measured it to fish responses of movement, stranding, and mortality, especially in the presence of ice cover.

  9. Estimating thermal regimes of bull trout and assessing the potential effects of climate warming on critical habitats

    USGS Publications Warehouse

    Jones, Leslie A.; Muhlfeld, Clint C.; Marshall, Lucy A.; McGlynn, Brian L.; Kershner, Jeffrey L.

    2013-01-01

    Understanding the vulnerability of aquatic species and habitats under climate change is critical for conservation and management of freshwater systems. Climate warming is predicted to increase water temperatures in freshwater ecosystems worldwide, yet few studies have developed spatially explicit modelling tools for understanding the potential impacts. We parameterized a nonspatial model, a spatial flow-routed model, and a spatial hierarchical model to predict August stream temperatures (22-m resolution) throughout the Flathead River Basin, USA and Canada. Model comparisons showed that the spatial models performed significantly better than the nonspatial model, explaining the spatial autocorrelation found between sites. The spatial hierarchical model explained 82% of the variation in summer mean (August) stream temperatures and was used to estimate thermal regimes for threatened bull trout (Salvelinus confluentus) habitats, one of the most thermally sensitive coldwater species in western North America. The model estimated summer thermal regimes of spawning and rearing habitats at <13 C° and foraging, migrating, and overwintering habitats at <14 C°. To illustrate the useful application of such a model, we simulated climate warming scenarios to quantify potential loss of critical habitats under forecasted climatic conditions. As air and water temperatures continue to increase, our model simulations show that lower portions of the Flathead River Basin drainage (foraging, migrating, and overwintering habitat) may become thermally unsuitable and headwater streams (spawning and rearing) may become isolated because of increasing thermal fragmentation during summer. Model results can be used to focus conservation and management efforts on populations of concern, by identifying critical habitats and assessing thermal changes at a local scale.

  10. Sampling large geographic areas for rare species using environmental DNA: a study of bull trout Salvelinus confluentus occupancy in western Montana.

    PubMed

    McKelvey, K S; Young, M K; Knotek, W L; Carim, K J; Wilcox, T M; Padgett-Stewart, T M; Schwartz, M K

    2016-03-01

    This study tested the efficacy of environmental DNA (eDNA) sampling to delineate the distribution of bull trout Salvelinus confluentus in headwater streams in western Montana, U.S.A. Surveys proved fast, reliable and sensitive: 124 samples were collected across five basins by a single crew in c. 8 days. Results were largely consistent with past electrofishing, but, in a basin where S. confluentus were known to be scarce, eDNA samples indicated that S. confluentus were more broadly distributed than previously thought.

  11. Detecting declines in the abundance of a bull trout (Salvelinus confluentus) population: Understanding the accuracy, precision, and costs of our efforts

    USGS Publications Warehouse

    Al-Chokhachy, R.; Budy, P.; Conner, M.

    2009-01-01

    Using empirical field data for bull trout (Salvelinus confluentus), we evaluated the trade-off between power and sampling effort-cost using Monte Carlo simulations of commonly collected mark-recapture-resight and count data, and we estimated the power to detect changes in abundance across different time intervals. We also evaluated the effects of monitoring different components of a population and stratification methods on the precision of each method. Our results illustrate substantial variability in the relative precision, cost, and information gained from each approach. While grouping estimates by age or stage class substantially increased the precision of estimates, spatial stratification of sampling units resulted in limited increases in precision. Although mark-resight methods allowed for estimates of abundance versus indices of abundance, our results suggest snorkel surveys may be a more affordable monitoring approach across large spatial scales. Detecting a 25% decline in abundance after 5 years was not possible, regardless of technique (power = 0.80), without high sampling effort (48% of study site). Detecting a 25% decline was possible after 15 years, but still required high sampling efforts. Our results suggest detecting moderate changes in abundance of freshwater salmonids requires considerable resource and temporal commitments and highlight the difficulties of using abundance measures for monitoring bull trout populations.

  12. Energy composition of diet affects muscle fiber recruitment, body composition, and growth trajectory in rainbow trout (Oncorhnychus mykiss)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Energy composition of diet affects muscle fiber recruitment, body composition, and growth trajectory in rainbow trout (Oncorhnychus mykiss) The cost and scarcity of key ingredients for aquaculture feed formulation call for a wise use of resources, especially dietary proteins and energy. For years t...

  13. Standard Local Operating Procedures for Endangered Species (SLOPES) for Selected Nationwide Permit Activities Affecting Bull Trout in Western Montana and Northern Idaho. Endangered Species Act Section 7 Consultation: Biological Opinion

    DTIC Science & Technology

    2013-05-17

    57 Table 8. Nature of expected bull trout take and level of SLOPES activity for the action area within each core area...Replacement of existing stream crossings will be designed to promote natural sediment transport, allow maximum fluvial debris movement, and improve... natural movement of existing streambed material. Utility Line Activities: (NWP 12 type actions) Utility line construction or repair could involve

  14. Extensive feeding on sockeye salmon Oncorhynchus nerka smolts by bull trout Salvelinus confluentus during initial outmigration into a small, unregulated and inland British Columbia river.

    PubMed

    Furey, N B; Hinch, S G; Lotto, A G; Beauchamp, D A

    2015-01-01

    Stomach contents were collected and analysed from 22 bull trout Salvelinus confluentus at the edge of the Chilko Lake and Chilko River in British Columbia, Canada, during spring outmigration of sockeye salmon Oncorhynchus nerka smolts. Twenty of the 22 (>90%) stomachs contained prey items, virtually all identifiable prey items were outmigrant O. nerka smolts and stomach contents represented a large portion (0·0-12·6%) of estimated S. confluentus mass. The results demonstrate nearly exclusive and intense feeding by S. confluentus on outmigrant smolts, and support recent telemetry observations of high disappearance rates of O. nerka smolts leaving large natural lake systems prior to entering high-order unregulated river systems.

  15. Relationships between water temperatures and upstream migration, cold water refuge use, and spawning of adult bull trout from the Lostine River, Oregon, USA

    USGS Publications Warehouse

    Howell, P.J.; Dunham, J.B.; Sankovich, P.M.

    2010-01-01

    Understanding thermal habitat use by migratory fish has been limited by difficulties in matching fish locations with water temperatures. To describe spatial and temporal patterns of thermal habitat use by migratory adult bull trout, Salvelinus confluentus, that spawn in the Lostine River, Oregon, we employed a combination of archival temperature tags, radio tags, and thermographs. We also compared temperatures of the tagged fish to ambient water temperatures to determine if the fish were using thermal refuges. The timing and temperatures at which fish moved upstream from overwintering areas to spawning locations varied considerably among individuals. The annual maximum 7-day average daily maximum (7DADM) temperatures of tagged fish were 16-18 ??C and potentially as high as 21 ??C. Maximum 7DADM ambient water temperatures within the range of tagged fish during summer were 18-25 ??C. However, there was no evidence of the tagged fish using localized cold water refuges. Tagged fish appeared to spawn at 7DADM temperatures of 7-14 ??C. Maximum 7DADM temperatures of tagged fish and ambient temperatures at the onset of the spawning period in late August were 11-18 ??C. Water temperatures in most of the upper Lostine River used for spawning and rearing appear to be largely natural since there has been little development, whereas downstream reaches used by migratory bull trout are heavily diverted for irrigation. Although the population effects of these temperatures are unknown, summer temperatures and the higher temperatures observed for spawning fish appear to be at or above the upper range of suitability reported for the species. Published 2009. This article is a US Governmentwork and is in the public domain in the USA.

  16. 75 FR 13715 - Endangered and Threatened Wildlife and Plants; Revised Designation of Critical Habitat for Bull...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-23

    ...; Revised Designation of Critical Habitat for Bull Trout in the Coterminous United States AGENCY: Fish and... of critical habitat for the bull trout (Salvelinus confluentus) ] under the Endangered Species Act of... January 14, 2010, we published our proposed revised designation of critical habitat for bull trout in...

  17. Estimating recruitment dynamics and movement of rainbow trout (Oncorhynchus mykiss) in the Colorado River in Grand Canyon using an integrated assessment model

    USGS Publications Warehouse

    Korman, Josh; Martell, Steven J.D.; Walters, Carl J.; Makinster, Andrew S.; Coggins, Lewis G.; Yard, Michael D.; Persons, William R.

    2012-01-01

    We used an integrated assessment model to examine effects of flow from Glen Canyon Dam, Arizona, USA, on recruitment of nonnative rainbow trout (Oncorhynchus mykiss) in the Colorado River and to estimate downstream migration from Glen Canyon to Marble Canyon, a reach used by endangered native fish. Over a 20-year period, recruitment of rainbow trout in Glen Canyon increased with the annual flow volume and when hourly flow variation was reduced and after two of three controlled floods. The model predicted that approximately 16 000 trout·year–1 emigrated to Marble Canyon and that the majority of trout in this reach originate from Glen Canyon. For most models that were examined, over 70% of the variation in emigration rates was explained by variation in recruitment in Glen Canyon, suggesting that flow from the dam controls in large part the extent of potential negative interactions between rainbow trout and native fish. Controlled floods and steadier flows, which were originally aimed at partially restoring conditions before the dam (greater native fish abundance and larger sand bars), appear to have been more beneficial to nonnative rainbow trout than to native fish.

  18. Effects of increased discharge on spawning and age-0 recruitment of rainbow trout in the Colorado River at Lees Ferry, Arizona

    USGS Publications Warehouse

    Avery, Luke A.; Korman, Josh; Persons, William R.

    2015-01-01

    Negative interactions of Rainbow Trout Oncorhynchus mykiss with endangered Humpback Chub Gila cypha pose challenges to the operation of Glen Canyon Dam (GCD) to manage for both species in the Colorado River. Operations to enhance the Rainbow Trout tailwater fishery may lead to an increase in downstream movement of the trout to areas where they are likely to interact with Humpback Chub. We evaluated the effects of dam operations on age-0 Rainbow Trout in the tailwater fishery to inform managers about how GCD operations could benefit a tailwater fishery for Rainbow Trout; although this could affect a Humpback Chub population farther downstream. A near year-long increase in discharge at GCD in 2011 enabled us to evaluate whether high and stable flows led to increased spawning and production of age-0 Rainbow Trout compared with other years. Rainbow Trout spawning was monitored by fitting a model to observed redd counts to estimate the number of redds created over a spawning season. Data collected during electrofishing trips in July–September and November were used to acquire age-0 trout population and mortality rate estimates. We found that high and stable flows in 2011 resulted in 3,062 redds (1.7 times the mean of all survey years) and a population estimate of 686,000 age-0 Rainbow Trout (second highest on record). Despite high initial abundance, mortality remained low through the year (0.0043%/d) resulting in significant recruitment with a record high November population estimate of 214,000 age-0 Rainbow Trout. Recent monitoring indicates this recruitment event was followed by an increase in downstream migration, which may lead to increased interactions with downstream populations of Humpback Chub. Consequently, while our results indicate that manipulating flow at GCD can be used to manage Rainbow Trout spawning and recruitment, fisheries managers should use flow manipulation in moderation to minimize downstream migration in order to reduce negative

  19. The influence of history and contemporary stream hydrology on the evolution of genetic diversity within species: an examination of microsatellite DNA variation in bull trout, Salvelinus confluentus (Pisces: Salmonidae).

    PubMed

    Costello, A B; Down, T E; Pollard, S M; Pacas, C J; Taylor, E B

    2003-02-01

    An understanding of the relative roles of historical and contemporary factors in structuring genetic variation is a fundamental, but understudied aspect of geographic variation. We examined geographic variation in microsatellite DNA allele frequencies in bull trout (Salvelinus confluentus, Salmonidae) to test hypotheses concerning the relative roles of postglacial dispersal (historical) and current landscape features (contemporary) in structuring genetic variability and population differentiation. Bull trout exhibit relatively low intrapopulation microsatellite variation (average of 1.9 alleles per locus, average He = 0.24), but high levels of interpopulation divergence (F(ST) = 0.39). We found evidence of historical influences on microsatellite variation in the form of a decrease in the number of alleles and heterozygosities in populations on the periphery of the range relative to populations closer to putative glacial refugia. In addition, one region of British Columbia that was colonized later during deglaciation and by more indirect watershed connections showed less developed and more variable patterns of isolation by distance than a similar region colonized earlier and more directly from refugia. Current spatial and drainage interconnectedness among sites and the presence of migration barriers (falls and cascades) within individual streams were found to be important contemporary factors influencing historical patterns of genetic variability and interpopulation divergence. Our work illustrates the limited utility of equilibrium models to delineate population structure and patterns of genetic diversity in recently founded populations or those inhabiting highly heterogeneous environments, and it highlights the need for approaches incorporating a landscape context for population divergence. Substantial microsatellite DNA divergence among bull trout populations may also signal divergence in traits important to population persistence in specific environments.

  20. Supplement Analysis for the Watershed Management Program EIS (DOE/EIS-0265/SA-103) - Install Fish Screens to Protect ESA Listed Steelhead and Bull Trout in the Walla Walla Basin – Phase II

    SciTech Connect

    Stewart, Shannon C.

    2003-06-11

    Proposed Action: Install Fish Screens to Protect ESA Listed Steelhead and Bull Trout in the Walla Walla Basin – Phase II Minor Diversion Screen Installations. BPA is proposing to provide cost share for a program that will protect ESA-listed salmonid species in the Walla Walla River Basin through the installation of state and federally approved fish screen on over 300 water diversions in the Walla Walla River Basin. This program will involve a wide variety of projects including the installation of screens for both pump and gravity fed surface water diversions. This project will be implemented in conjunction with the Walla Walla County Conservation District, Columbia County Conservation District, Washington Department of Fish and Wildlife, Walla Walla Community College, Washington Department of Ecology, and local irrigators. ESA-listed steelhead and bull trout are presently at risk in the Walla Walla Basin as a result of a combination of factors that primarily involve insufficient flow, extensive habitat degradation, and mortality from surface water diversions. Unscreened or improperly screened diversions can damage fish scaling and induce stress, both of which can be lethal. They are also known to cause migration delays and increased predation; impinge fish against screen surfaces; or, in cases where screen mesh size is too large, allow juvenile fish to be drawn directly into functioning irrigation systems resulting in direct mortality. The goal of this project is to eliminate imminent mortality risks to ESA-listed fish arising from inadequate irrigation diversions in the Walla Walla Basin by upgrading screens to current state and federal juvenile fish screen standards.

  1. Contrasting patterns of reef utilization and recruitment of coral trout ( Plectropomus leopardus) and snapper ( Lutjanus carponotatus) at One Tree Island, southern Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    Kingsford, M. J.

    2009-03-01

    Patterns of abundance, age structure and recruitment of coral trout ( Plectropomus leopardus) and snapper ( Lutjanus carponotatus) were described in different environments, which varied in benthic cover, in a 12-yr study at One Tree Island. It was hypothesized that both taxa would show strong preferences to different environments and benthic cover and that patterns would be consistent through time. Plectropomus leopardus were abundant on the reef slope and seaward edge of the lagoon, where live coral cover was high, and recruitment was generally low, in all environments. The population was sustained by a trickle of recruits, and total abundance varied little after 10 to 25 yr of protection in a no-take area, suggesting P. leopardus had reached an environment-related carrying capacity. Protogynous P. leopardus recruited to shallow environments at sites with 20% or more hard live coral and age data indicated the abundance of fish on the reef slope was from redistribution. Most recruits of gonochoristic L. carponotatus (<150 mm Standard length, SL) were found in the lagoonal environments, and adults were rare on the reef slope. Abundance of recruit L. carponotatus and P. leopardus did not correlate with percent cover of live and soft coral within environments. Recruits of L. carponotatus were usually rare in all lagoonal environments, but in 2003, many recruits (80 to 120 mm SL) were found in lagoonal environments with low and high hard live coral cover. A substantial proportion of the population (age max 18 yr) was from strong recruitment events. In 2003 and 2004, total abundance of L. carponotatus was supported by 1 year class 51.7 and 41% respectively. The utilization of environments and types of substrata varied among taxa and in some cases among life-history stages. There was also temporal variation in the importance of some environments (e.g. Lagoon Centre).

  2. Effects of open-entry spike-bull, limited-entry branched-bull harvesting on elk composition in Washington

    USGS Publications Warehouse

    Bender, L.C.; Fowler, P.E.; Bernatowicz, J.A.; Musser, J.L.; Stream, L.E.

    2002-01-01

    The Washington Department of Fish and Wildlife implemented an open-entry spike-bull, limited-entry branched-bull elk (Cervus elaphus) harvest strategy in the Blue Mountains (1989), Yakima (1994), and Colockum (1994) herd areas of Washington state with goals of increasing numbers of adult bulls to increase breeding efficiency and possibly calf recruitment. Numbers of total bulls/100 cows (x??=5.4) and branched bulls/100 cows (x??=5.3) increased with the change in harvest strategy, while yearling bulls/100 cows remained unchanged; calves/100 cows declined (x??=-8.6). Calves/100 cows were always negatively correlated with both total bulls/100 cows and branched bulls/100 cows in each area; correlations were significant in 5 of 9 comparisons with total-bull ratios and 5 of 9 comparisons with branched-bull ratios. Open-entry spike-bull, limited-entry branched-bull harvesting can be used to increase total-bull and branched-bulls ratios in hunted elk populations. However, the increased ratios of bulls and branched bulls were unimportant in influencing calf recruitment, likely because of the importance of female condition on production and survival of young.

  3. Paenibacillus thiaminolyticus is not the cause of thiamine deficiency impeding lake trout (Salvelinus namaycush) recruitment in the Great Lakes

    USGS Publications Warehouse

    Richter, Catherine A.; Evans, Allison N.; Wright-Osment, Maureen K.; Zajicek, James L.; Heppell, Scott A.; Riley, Stephen C.; Krueger, Charles C.; Tillitt, Donald E.

    2012-01-01

    Thiamine (vitamin B1) deficiency is a global concern affecting wildlife, livestock, and humans. In Great Lakes salmonines, thiamine deficiency causes embryo mortality and is an impediment to restoration of native lake trout (Salvelinus namaycush) stocks. Thiamine deficiency in fish may result from a diet of prey with high levels of thiaminase I. The discoveries that the bacterial species Paenibacillus thiaminolyticus produces thiaminase I, is found in viscera of thiaminase-containing prey fish, and causes mortality when fed to lake trout in the laboratory provided circumstantial evidence implicating P. thiaminolyticus. This study quantified the contribution of P. thiaminolyticus to the total thiaminase I activity in multiple trophic levels of Great Lakes food webs. Unexpectedly, no relationship between thiaminase activity and either the amount of P. thiaminolyticus thiaminase I protein or the abundance of P. thiaminolyticus cells was found. These results demonstrate that P. thiaminolyticus is not the primary source of thiaminase activity affecting Great Lakes salmonines and calls into question the long-standing assumption that P. thiaminolyticus is the source of thiaminase in other wild and domestic animals.

  4. The pyloric caeca area is a major site for IgM(+) and IgT(+) B cell recruitment in response to oral vaccination in rainbow trout.

    PubMed

    Ballesteros, Natalia A; Castro, Rosario; Abos, Beatriz; Rodríguez Saint-Jean, Sylvia S; Pérez-Prieto, Sara I; Tafalla, Carolina

    2013-01-01

    Although previous studies have characterized some aspects of the immune response of the teleost gut in response to diverse pathogens or stimuli, most studies have focused on the posterior segments exclusively. However, there are still many details of how teleost intestinal immunity is regulated that remain unsolved, including the location of IgM(+) and IgT(+) B cells along the digestive tract and their role during the course of a local stimulus. Thus, in the current work, we have studied the B cell response in five different segments of the rainbow trout (Oncorhynchus mykiss) digestive tract in both naïve fish and fish orally vaccinated with an alginate-encapsulated DNA vaccine against infectious pancreatic necrosis virus (IPNV). IgM(+) and IgT(+) cells were identified all along the tract with the exception of the stomach in naïve fish. While IgM(+) cells were mostly located in the lamina propria (LP), IgT(+) cells were primarily localized as intraepithelial lymphocytes (IELs). Scattered IgM(+) IELs were only detected in the pyloric caeca. In response to oral vaccination, the pyloric caeca region was the area of the digestive tract in which a major recruitment of B cells was demonstrated through both real time PCR and immunohistochemistry, observing a significant increase in the number of both IgM(+) and IgT(+) IELs. Our findings demonstrate that both IgM(+) and IgT(+) respond to oral stimulation and challenge the paradigm that teleost IELs are exclusively T cells. Unexpectedly, we have also detected B cells in the fat tissue associated to the digestive tract that respond to vaccination, suggesting that these cells surrounded by adipocytes also play a role in mucosal defense.

  5. Embryotoxicity of an extract from Great Lakes lake trout to rainbow trout and lake trout

    SciTech Connect

    Wright, P.J.; Tillitt, D.E.

    1995-12-31

    Aquatic ecosystems such as the Great Lakes are known to be contaminated with chemicals that are toxic to fish. However, the role of these contaminants in reproductive failures of fishes, such as lake trout recruitment, has remained controvertible. It was the objective to evaluate dioxin-like embryotoxicity of a complex mixture of chemicals and predict their potential to cause the lack of recruitment in Great Lakes lake trout. Graded doses of a complex environmental extract were injected into eggs of both rainbow trout and lake trout. The extract was obtained from whole adult lake trout collected from Lake Michigan in 1988. The extract was embryotoxic in rainbow trout, with LD50 values for Arlee strain and Erwin strain of 33 eggEQ and 14 eggEQ respectively. The LOAEL for hemorrhaging, yolk-sac edema, and craniofacial deformities in rainbow trout were 2, 2, and 4 eggEQ, respectively. Subsequent injections of the extract into lake trout eggs were likewise embryotoxic, with an LD50 value of 7 eggEQ. The LOAEL values for the extract in lake trout for hemorrhaging, yolk-sac edema, and craniofacial deformities were 0.1, 1, and 2 eggEQ, respectively. The current levels of contaminants in lake trout eggs are above the threshold for hemorrhaging and yolk-sac edema. The results also support the use of an additive model of toxicity to quantify PCDDs, PCDFs, Non-o-PCBs, and Mono-o-PCBs in relation to early life stage mortality in Lake Michigan lake trout.

  6. Role of climate and invasive species in structuring trout distributions in the interior Columbia River Basin, USA

    USGS Publications Warehouse

    Wenger, Seth J.; Isaak, Daniel J.; Dunham, Jason B.; Fausch, Kurt D.; Luce, Charles H.; Neville, Helen M.; Rieman, Bruce E.; Young, Michael K.; Nagel, David E.; Horan, Dona L.; Chandler, Gwynne L.

    2011-01-01

    Recent and projected climate warming trends have prompted interest in impacts on coldwater fishes. We examined the role of climate (temperature and flow regime) relative to geomorphology and land use in determining the observed distributions of three trout species in the interior Columbia River Basin, USA. We considered two native species, cutthroat trout (Oncorhynchus clarkii) and bull trout (Salvelinus confluentus), as well as nonnative brook trout (Salvelinus fontinalis). We also examined the response of the native species to the presence of brook trout. Analyses were conducted using multilevel logistic regression applied to a geographically broad database of 4165 fish surveys. The results indicated that bull trout distributions were strongly related to climatic factors, and more weakly related to the presence of brook trout and geomorphic variables. Cutthroat trout distributions were weakly related to climate but strongly related to the presence of brook trout. Brook trout distributions were related to both climate and geomorphic variables, including proximity to unconfined valley bottoms. We conclude that brook trout and bull trout are likely to be adversely affected by climate warming, whereas cutthroat trout may be less sensitive. The results illustrate the importance of considering species interactions and flow regime alongside temperature in understanding climate effects on fish.

  7. Suppression of invasive lake trout in an isolated backcountry lake in Glacier National Park

    USGS Publications Warehouse

    Fredenberg, C. R.; Muhlfeld, Clint C.; Guy, Christopher S.; D'Angelo, Vincent S.; Downs, Christopher C.; Syslo, John M.

    2017-01-01

    Fisheries managers have implemented suppression programmes to control non-native lake trout, Salvelinus namaycush (Walbaum), in several lakes throughout the western United States. This study determined the feasibility of experimentally suppressing lake trout using gillnets in an isolated backcountry lake in Glacier National Park, Montana, USA, for the conservation of threatened bull trout, Salvelinus confluentus (Suckley). The demographics of the lake trout population during suppression (2009–2013) were described, and those data were used to assess the effects of suppression scenarios on population growth rate (λ) using an age-structured population model. Model simulations indicated that the population was growing exponentially (λ = 1.23, 95% CI: 1.16–1.28) prior to suppression. However, suppression resulted in declining λ(0.61–0.79) for lake trout, which was concomitant with stable bull trout adult abundances. Continued suppression at or above observed exploitation levels is needed to ensure continued population declines.

  8. Genetic strategies for lake trout rehabilitation: a synthesis

    USGS Publications Warehouse

    Burnham-Curtis, Mary K.; Krueger, Charles C.; Schreiner, Donald R.; Johnson, James E.; Stewart, Thomas J.; Horrall, Ross M.; MacCallum, Wayne R.; Kenyon, Roger; Lange, Robert E.

    1995-01-01

    The goal of lake trout rehabilitation efforts in the Great Lakes has been to reestablish inshore lake trout (Salvelinus namaycush) populations to self-sustaining levels. A combination of sea lamprey control, stocking of hatchery-reared lake trout, and catch restrictions were used to enhance remnant lake trout stocks in Lake Superior and reestablish lake trout in Lakes Michigan, Huron, Erie, and Ontario. Genetic diversity is important for the evolution and maintenance of successful adaptive strategies critical to population restoration. The loss of genetic diversity among wild lake trout stocks in the Great Lakes imposes a severe constraint on lake trout rehabilitation. The objective of this synthesis is to address whether the particular strain used for stocking combined with the choice of stocking location affects the success or failure of lake trout rehabilitation. Poor survival, low juvenile recruitment, and inefficient habitat use are three biological impediments to lake trout rehabilitation that can be influenced by genetic traits. Evidence supports the hypothesis that the choices of appropriate lake trout strain and stocking locations enhance the survival of lake trout stocked into the Great Lakes. Genetic strategies proposed for lake trout rehabilitation include conservation of genetic diversity in remnant stocks, matching of strains with target environments, stocking a greater variety of lake trout phenotypes, and rehabilitation of diversity at all trophic levels.

  9. Red Bull Stratos Presentation

    NASA Video Gallery

    Red Bull Stratos High Performance Director Andy Walshe & Technical Project Director Art Thompson share the Stratos story with JSC. Supported by a team of experts, Felix Baumgartner reached 128,100 ...

  10. 29 CFR 1918.84 - Bulling cargo.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false Bulling cargo. 1918.84 Section 1918.84 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Handling Cargo § 1918.84 Bulling cargo. (a) Bulling cargo shall be done with the bull line led directly from the heel block. However, bulling may be done from...

  11. 29 CFR 1918.84 - Bulling cargo.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 7 2013-07-01 2013-07-01 false Bulling cargo. 1918.84 Section 1918.84 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Handling Cargo § 1918.84 Bulling cargo. (a) Bulling cargo shall be done with the bull line led directly from the heel block. However, bulling may be done from...

  12. 29 CFR 1918.84 - Bulling cargo.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false Bulling cargo. 1918.84 Section 1918.84 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Handling Cargo § 1918.84 Bulling cargo. (a) Bulling cargo shall be done with the bull line led directly from the heel block. However, bulling may be done from...

  13. 29 CFR 1918.84 - Bulling cargo.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Bulling cargo. 1918.84 Section 1918.84 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Handling Cargo § 1918.84 Bulling cargo. (a) Bulling cargo shall be done with the bull line led directly from the heel block. However, bulling may be done from...

  14. 29 CFR 1918.84 - Bulling cargo.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Bulling cargo. 1918.84 Section 1918.84 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Handling Cargo § 1918.84 Bulling cargo. (a) Bulling cargo shall be done with the bull line led directly from the heel block. However, bulling may be done from...

  15. 9 CFR 78.14 - Rodeo bulls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Interstate Movement of Cattle Because of Brucellosis § 78.14 Rodeo bulls. (a) A rodeo bull that is test... date of being tested, may be moved interstate only if the bull meets the requirements for cattle...

  16. 9 CFR 78.14 - Rodeo bulls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Interstate Movement of Cattle Because of Brucellosis § 78.14 Rodeo bulls. (a) A rodeo bull that is test... date of being tested, may be moved interstate only if the bull meets the requirements for cattle...

  17. Lake trout demographics in relation to burbot and coregonine populations in the Algonquin Highlands, Ontario

    USGS Publications Warehouse

    Carl, L.M.

    2008-01-01

    The objective of the study was to test the hypothesis that lake trout populations change in relation to cisco, lake whitefish, round whitefish and burbot populations in lakes in the Algonquin Highlands region of Ontario. Lake trout population change is greatest where cisco and lake whitefish are present. Lake trout populations in lakes without either coregonine tend to have small adults and many juveniles. Where cisco or lake whitefish are present, adult lake trout are large, juvenile abundance is low, and the stock-recruit relationship appears to be uncoupled likely due to a larval bottleneck. Lake trout populations in these lakes may be sensitive to overfishing and recruitment failure. Lake trout populations do not appear to change in relation to round whitefish. There appears to be an indirect positive change on juvenile lake trout abundance through reductions in the density of benthic coregonines in the presence of large, hypolimnetic burbot. ?? 2007 Springer Science+Business Media B.V.

  18. 14. BULL SHAFT, BULL RING AND PINION, AND DRUM. TOP ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. BULL SHAFT, BULL RING AND PINION, AND DRUM. TOP OF PIER III, GRANITE COPING, AND PLAIN CONCRETE PIER BELOW. DETAILS OF WEST PIER PROTECTION FRAMING AT PIER. WILLBRIDGE IN BACKGROUND. - Burlington Northern Railroad Bridge, Spanning Willamette River at River Mile 6.9, Portland, Multnomah County, OR

  19. 75 FR 63897 - Endangered and Threatened Wildlife and Plants; Revised Designation of Critical Habitat for Bull...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-18

    ...We, the U.S. Fish and Wildlife Service, are revising critical habitat for the bull trout (Salvelinus confluentus) under the Endangered Species Act of 1973, as amended (Act). We are designating a total of 31,750.8 km (19,729.0 mi) of streams (which includes 1,213.2 km (754.0 mi) of marine shoreline) and are designating a total of 197,589.2 ha (488,251.7 ac) of reservoirs and lakes. The areas......

  20. Effects of bull elk demographics on age categories of harem bulls

    USGS Publications Warehouse

    Bender, L.C.

    2002-01-01

    Many management strategies for elk (Cervus elaphus) emphasize increasing numbers of mature bulls in the population. These strategies are usually assumed to enhance productivity via increased breeding by mature bulls. I compared age classes of harem bulls during the peak of the rut under 4 bull harvest strategies that resulted in different bull:cow ratios, mature bull:cow ratios, bull mortality rates, and proportions of mature bulls in the autumn (pre-hunting season) population. Proportions of harems held by differing age classes of bulls [mature (P84% of harems only in populations where mature bull:cow ratios exceeded 21:100 in the autumn population. Interaction of mature bull ratios in the autumn population, harem size, and bull selectivity in the harvest strategy must be considered if increased breeding by mature harem bulls is a management goal.

  1. Regulation of an unexploited brown trout population in Spruce Creek, Pennsylvania

    USGS Publications Warehouse

    Carline, R.F.

    2006-01-01

    The purpose of this paper is to describe the annual variations in the density of an unexploited population of lotic brown trout Salmo trutta that has been censused annually for 19 years and to explore the importance of density-independent and density-dependent processes in regulating population size. Brown trout density and indices of stream discharge and water temperature were related to annual variations in natural mortality, recruitment, and growth. Annual mortality of age-1 and older (age-1+) brown trout ranged from 0.30 to 0.75 and was best explained by discharge during spring and by brown trout density. Recruitment to age 1 varied fivefold. Density of age-1 brown trout was inversely related to spawner density and positively related to discharge during the fall spawning period. The median length of age-1 brown trout was positively related to discharge during summer and fall. Relative weight was inversely related to the density of age-2+ brown trout. The interactive effects of discharge and brown trout density accounted for most of the annual variation in mortality, recruitment, and growth during the first year of life. Annual trends in the abundance of age-1+ brown trout were largely dictated by natural mortality. ?? Copyright by the American Fisheries Society 2006.

  2. Bulling among yearling feedlot steers.

    PubMed

    Pierson, R E; Jensen, R; Braddy, P M; Horton, D P; Christie, R M

    1976-09-01

    In a survey to determine the cause of illness and deaths among yearling feedlot cattle, bulling was found to be one of the major problems. During the years 1971-1974, 54,913 (2.88%) steers became bullers and represented an annual loss of around +325,000. Some of the causes of bulling were found to be hormones, either as implants or in the feed. In 1974, from 1,988 necropsies, it was determined that 83 steers died from riding injuries.

  3. Lake trout rehabilitation in Lake Erie: a case history

    USGS Publications Warehouse

    Cornelius, Floyd C.; Muth, Kenneth M.; Kenyon, Roger

    1995-01-01

    Native lake trout (Salvelinus namaycush) once thrived in the deep waters of eastern Lake Erie. The impact of nearly 70 years of unregulated exploitation and over 100 years of progressively severe cultural eutrophication resulted in the elimination of lake trout stocks by 1950. Early attempts to restore lake trout by stocking were unsuccessful in establishing a self-sustaining population. In the early 1980s, New York's Department of Environmental Conservation, Pennsylvania's Fish and Boat Commission, and the U.S. Fish and Wildlife Service entered into a cooperative program to rehabilitate lake trout in the eastern basin of Lake Erie. After 11 years of stocking selected strains of lake trout in U.S. waters, followed by effective sea lamprey control, lake trout appear to be successfully recolonizing their native habitat. Adult stocks have built up significantly and are expanding their range in the lake. Preliminary investigations suggest that lake trout reproductive habitat is still adequate for natural reproduction, but natural recruitment has not been documented. Future assessments will be directed toward evaluation of spawning success and tracking age-class cohorts as they move through the fishery.

  4. Fertility of yearling beef bulls during mating.

    PubMed

    Ellis, R W; Rupp, G P; Chenoweth, P J; Cundiff, L V; Lunstra, D D

    2005-08-01

    Crossbred (Bos taurus) yearling beef bulls were assessed for breeding soundness and physical traits prior to multi-sire natural mating at pasture. Bulls (n = 60) were assigned to six groups of nine or 10 bulls and two bull-groups were rotated on 14-day intervals during a 63-day mating season in each breeding herd (n = 3) of 191-196 cows. The remaining bulls (n = 14) were maintained under similar environmental conditions without mating exposure. Bulls were observed during mating and assessed for breeding soundness and changes following mating. Bulls used for breeding (UFB) lost 77 kg of body weight and declined from body condition scores of 6 to 4.5, whereas bulls not used for breeding (NUB) maintained body condition scores of 6 and gained 27 kg. The UFB bulls incurred a 75% total injury rate with 63% incidence of lameness and 12% incidence of reproductive injuries, resulting in a 22% attrition rate. Only 45% were physically sound at the end of mating. Scrotal circumference declined in UFB bulls (-4.58%) and increased in NUB bulls (2.49%). From the 98% BSE-satisfactory rate (UFB) prior to breeding, only 61% were BSE-satisfactory post-breeding. The NUB bulls declined from 57 to 36% satisfactory. The BSE classification was influenced by significant increases in abnormal spermatozoa (primary and secondary), which was significantly associated with injuries incurred during mating. Group and breed differences in injury rates and BSE-status following mating were evident. Environmental conditions and mating activity influenced bull seminal quality and physical condition. Pregnancy rates in all three breeding herds (91-96%) were similar, with insignificant differences between bull-groups; the effects of physical and reproductive changes on individual bull fertility were immeasurable.

  5. Acoustic estimates of abundance and distribution of spawning lake trout on Sheboygan Reef in Lake Michigan

    USGS Publications Warehouse

    Warner, D.M.; Claramunt, R.M.; Janssen, J.; Jude, D.J.; Wattrus, N.

    2009-01-01

    Efforts to restore self-sustaining lake trout (Salvelinus namaycush) populations in the Laurentian Great Lakes have had widespread success in Lake Superior; but in other Great Lakes, populations of lake trout are maintained by stocking. Recruitment bottlenecks may be present at a number of stages of the reproduction process. To study eggs and fry, it is necessary to identify spawning locations, which is difficult in deep water. Acoustic sampling can be used to rapidly locate aggregations of fish (like spawning lake trout), describe their distribution, and estimate their abundance. To assess these capabilities for application to lake trout, we conducted an acoustic survey covering 22 km2 at Sheboygan Reef, a deep reef (<40 m summit) in southern Lake Michigan during fall 2005. Data collected with remotely operated vehicles (ROV) confirmed that fish were large lake trout, that lake trout were 1–2 m above bottom, and that spawning took place over specific habitat. Lake trout density exhibited a high degree of spatial structure (autocorrelation) up to a range of ~190 m, and highest lake trout and egg densities occurred over rough substrates (rubble and cobble) at the shallowest depths sampled (36–42 m). Mean lake trout density in the area surveyed (~2190 ha) was 5.8 fish/ha and the area surveyed contained an estimated 9500–16,000 large lake trout. Spatial aggregation in lake trout densities, similarity of depths and substrates at which high lake trout and egg densities occurred, and relatively low uncertainty in the lake trout density estimate indicate that acoustic sampling can be a useful complement to other sampling tools used in lake trout restoration research.

  6. The 1000 bull genome project

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To meet growing global demands for high value protein from milk and meat, rates of genetic gain in domestic cattle must be accelerated. At the same time, animal health and welfare must be considered. The 1000 bull genomes project supports these goals by providing annotated sequence variants and ge...

  7. Lake trout rehabilitation in Lake Ontario

    USGS Publications Warehouse

    Elrod, Joseph H.; O'Gorman, Robert; Schneider, Clifford P.; Eckert, Thomas H.; Schaner, Ted; Bowlby, James N.; Schleen, Larry P.

    1995-01-01

    Attempts to maintain the native lake trout (Salvelinus namaycush) population in Lake Ontario by stocking fry failed and the species was extirpated by the 1950s. Hatchery fish stocked in the 1960s did not live to maturity because of sea lamprey (Petromyzon marinus) predation and incidental commercial harvest. Suppression of sea lampreys began with larvicide treatments of Lake Ontario tributaries in 1971 and was enhanced when the tributaries of Oneida Lake and Lake Erie were treated in the 1980s. Annual stocking of hatchery fish was resumed with the 1972 year class and peaked at about 1.8 million yearlings and 0.3 million fingerlings from the 1985–1990 year classes. Survival of stocked yearlings declined over 50% in the 1980 s and was negatively correlated with the abundance of lake trout > 550 mm long (r = −0.91, P < 0.01, n = 12). A slot length limit imposed by the State of New York for the 1988 fishing season reduced angler harvest. Angler harvest in Canadian waters was 3 times higher in eastern Lake Ontario than in western Lake Ontario. For the 1977–1984 year classes, mean annual survival rate of lake trout age 6 and older was 0.45 (range: 0.35–0.56). In U.S. waters during 1985–1992, the total number of lake trout harvested by anglers was about 2.4 times greater than that killed by sea lampreys. The number of unmarked lake trout < 250 mm long in trawl catches in 1978–1992 was not different from that expected due to loss of marks and failure to apply marks at the hatchery, and suggested that recruitment of naturally-produced fish was nil. However, many of the obstacles which may have impeded lake trout rehabilitation in Lake Ontario during the 1980s are slowly being removed, and there are signs of a general ecosystem recovery. Significant recruitment of naturally produced lake trout by the year 2000, one interim objective of the rehabilitation plan for the Lake, may be achieved.

  8. REDUCING EXPOSURE UNCERTAINTY FOR ASSESSMENT OF DIOXIN TOXICITY RISKS TO LAKE TROUT POPULATIONS IN THE GREAT LAKES

    EPA Science Inventory

    During the 20th century, declines of lake trout (Salvelinus namaycush) populations to virtual extinction in all the Great Lakes except Lake Superior were followed by failure of stocked lake trout to achieve recruitment through natural reproduction. Stresses such as excessive harv...

  9. The development of beef breeding bulls.

    PubMed

    Engelken, T J

    2008-08-01

    Management of the bull battery will have a dramatic impact on profitability of the cow/calf enterprise. It is critical that young bulls be selected and developed to maximize longevity and productivity for the eventual buyer. Bulls must be structurally sound, healthy, and have adequate libido in order to service the required number of females. Once bulls complete their first breeding season, special care must be taken in order to ensure that they recover and regain needed body condition and pass a bull breeding soundness examination (BBSE). Mature bulls that have reached their genetic potential for growth require less intensive management, but the health program and annual BBSE cannot be overlooked. Mature bulls are also more likely to carry venereal disease and should be screened according to local disease incidence and state regulations. All bulls, regardless of age, should be observed early during the breeding season to ensure that they are physically capable of mounting and servicing females. The establishment of a complete management program, especially for young bulls, is essential to ensure that ranch resources are used efficiently, including maintenance of a high level of reproductive performance of the cow herd.

  10. Influence of Didymosphenia geminata blooms on prey composition and associated diet and growth of Brown Trout

    USGS Publications Warehouse

    James, Daniel A.; Chipps, Steven R.

    2016-01-01

    We compared diet, stomach fullness, condition, and growth of Brown Trout Salmo trutta among streams with or without blooms of the benthic diatom Didymosphenia geminata in the Black Hills, South Dakota. In Rapid Creek, where D. geminata blooms covered ∼30% of the stream bottom, Brown Trout consumed fewer ephemeropterans (6–8% by weight) than individuals from two stream sections that have not had D. geminatablooms (Castle and Spearfish creeks; 13–39% by weight). In contrast, dipterans (primarily Chironomidae) represented a larger percentage of Brown Trout diets from Rapid Creek (D. geminata blooms present; 16–28% dry weight) compared with diets of trout from streams without D. geminata blooms (6–19% dry weight). Diets of small Brown Trout (100–199 mm TL) reflected the invertebrate species composition in benthic stream samples; in Rapid Creek, ephemeropterans were less abundant whereas dipterans were more abundant than in streams without D. geminata blooms. Stomach fullness and condition of Brown Trout from Rapid Creek were generally greater than those of Brown Trout from other populations. Linkages among invertebrate availability, diet composition, and condition of Brown Trout support the hypothesis that changes in invertebrate assemblages associated with D. geminata (i.e., more Chironomidae) could be contributing to high recruitment success for small Brown Trout in Rapid Creek.

  11. Dworshak Reservoir Investigations: Trout, Bass and Forage Species, 1988 Annual Report.

    SciTech Connect

    Statler, David P.

    1989-07-01

    For the period March 1988 through February 1989, an estimated 154,558 angler-hours were expended to catch 20,037 rainbow trout, 3,933 smallmouth bass, and 14 bull trout. Estimated catch of other species, including cutthroat trout, whitefish, suckers, and squawfish totalled 84. Subcatchable rainbow trout (135 to 185mm) caught and released by boat anglers comprised 53% (12,770) of the total catch. An estimated 88.6% of the smallmouth bass caught were under the minimum legal size limit of 305mm and were released. Estimated harvest of smallmouth bass was 450. The highest monthly catch rate documented for all species excluding kokanee was 1.81 fish per hour during October. Severe weather conditions during February reduced effort and no fish were documented in the creel. Cumulative catch rates through the survey period for rainbow trout and smallmouth bass were .13 and .02, respectively. The lowest monthly catch rates generally occurred when fishing pressure was the highest, with fishing effort targeting on kokanee during the May through July high use periods. The Arlee strain rainbow trout was somewhat more vulnerable to boat anglers than the Shasta strain during the early post-release period. 20 refs., 16 figs., 12 tabs.

  12. Progress toward lake trout restoration in Lake Michigan

    USGS Publications Warehouse

    Holey, Mark E.; Rybicki, Ronald W.; Eck, Gary W.; Brown, Edward H.; Marsden, J. Ellen; Lavis, Dennis S.; Toneys, Michael L.; Trudeau, Tom N.; Horrall, Ross M.

    1995-01-01

    Progress toward lake trout restoration in Lake Michigan is described through 1993. Extinction of the native lake trout fishery by sea lamprey predation, augmented by exploitation and habitat destruction, resulted in an extensive stocking program of hatchery-reared lake trout that began in 1965. Sea lamprey abundance was effectively controlled using selective chemical toxicants. The initial stocking produced a measurable wild year class of lake trout by 1976 in Grand Traverse Bay, but failed to continue probably due to excessive exploitation. The overall lack of successful reproduction lakewide by the late 1970s led to the development and implementation in 1985 of a focused inter-agency lakewide restoration plan by a technical committee created through the Lake Committee structure of the Great Lakes Fishery Commission. Strategies implemented in 1985 by the plan included setting a 40% total mortality goal lakewide, creating two large refuges designed to encompass historically the most productive spawning habitat and protect trout stocked over their home range, evaluating several lake trout strains, and setting stocking priorities throughout the lake. Target levels for stocking in the 1985 Plan have never been reached, and are much less than the estimated lakewide recruitment of yearlings by the native lake trout stocks. Since 1985, over 90% of the available lake trout have been stocked over the best spawning habitat, and colonization of the historically productive offshore reefs has occurred. Concentrations of spawning lake trout large enough for successful reproduction, based on observations of successful hatchery and wild stocks, have developed at specific reefs. Continued lack of recruitment at these specific sites suggests that something other than stotk abundance has limited success. Poor survival of lake trout eggs, assumed to be related to contaminant burden, occurred in the late 1970s and early 1980s, but survival has since increased to equal survival in the

  13. Lake trout population dynamics in the Northern Refuge of Lake Michigan: implications for future rehabilitation

    USGS Publications Warehouse

    Madenjiana, Charles P.; DeSorcie, Timothy J.

    2010-01-01

    The Northern Refuge was established in 1985 as part of the lake trout Salvelinus namaycush rehabilitation effort for Lake Michigan. To evaluate progress toward lake trout rehabilitation in the Northern Refuge, we conducted annual (1991–2008) gill-net surveys in the fall to assess the adult population and beam trawl surveys in the spring to assess naturally reproduced age-0 lake trout. Our criteria for evaluating progress included the density of “wild” age-0 fish within the Northern Refuge, the proportion of wild fish within the adult population, density of spawners, adult survival, growth, and wounding rate by sea lampreys Petromyzon marinus. No wild age-0 lake trout were caught in the Northern Refuge during 1991–2008. Overall, wild lake trout did not recruit to the adult population to any detectable degree. The mean density of spawning lake trout decreased from 45 fish·305 m of gill net−1·d−1 during 1991–1999 to only 4 fish·305 m−1·d−1 during 2000–2008. Although the sea lamprey wounding rate more than doubled between these two time periods, catch curve analysis revealed that mortality of adult lake trout actually decreased between the two periods. Therefore, the 90% decrease in abundance of spawning lake trout between the two periods could not be attributed to increased sea lamprey predation but instead was probably due in part to the reduced lake trout stocking rate during 1995–2005. The paucity of natural reproduction in the Northern Refuge during 1991–2008 most likely resulted from alewife Alosa pseudoharengus interference with lake trout reproduction and from the relatively low lake trout spawner density during 2000–2008. Our results suggest that the annual stocking rate of lake trout yearlings should be increased to at least 250,000 fish/reef to achieve greater densities of spawners.

  14. 9 CFR 78.14 - Rodeo bulls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.14 Rodeo bulls. (a) A rodeo bull that is test... classified as brucellosis negative based upon an official test conducted less than 365 days before the...

  15. Factors affecting spermatozoa morphology in beef bulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to evaluate factors affecting sperm morphology of bulls (n=908) collected at 320 days of age. Bulls were a composite breed (50% Red Angus, 25% Charolais, and 25% Tarentaise) born from 2002 to 2008 to dams fed levels of feed during mid and late gestation that were expe...

  16. Yearling Bull Breeding Soundness Examination: Special Considerations.

    PubMed

    Schrag, Nora; Larson, Robert L

    2016-07-01

    Accurate assessment of yearling bulls is important for the bottom line of all interested parties: the buyer, the seller, and the veterinarian performing the BSE. Special considerations and current research are highlighted and their application to the evaluation of yearling bulls is discussed.

  17. Sperm macromolecules associated with bull fertility.

    PubMed

    Kaya, Abdullah; Memili, Erdoğan

    2016-06-01

    Bull fertility, ability of the sperm to fertilize and activate the egg that sustain embryo development, is vitally important for effective and efficient production of cattle. Fertility is a complex trait with low heritability. Despite recent advances in genomic selection and possibility of enormous paternal benefits to profitable cattle production, there exist no reliable tests for evaluating semen quality and predicting bull fertility. This review focuses on sperm macromolecules such as transcripts, proteins and the epigenome, i.e., the functional genome that are associated with bull fertility. Generating new information in these systems is important beyond agriculture because such progress advances the fundamental science of the mammalian male gamete while at the same time introduces biotechnology into livestock production. Sperm macromolecules and epigenome markers associated with bull fertility can be used alone or in combination with the current SNP microarrays to determine sperm quality and to indicate bull fertility.

  18. Vestibular recruitment

    NASA Technical Reports Server (NTRS)

    Tsemakhov, S. G.

    1980-01-01

    Vestibular recruitment is defined through the analysis of several references. It is concluded that vestibular recruitment is an objective phenomenon which manifests itself during the affection of the vestibular receptor and thus serves as a diagnostic tool during affection of the vestibular system.

  19. Student Recruitment.

    ERIC Educational Resources Information Center

    Gibson, Amy R.

    A practical process for developing or improving student recruitment programs for Catholic schools is presented in this handbook. Planning for and preparing the recruitment program is discussed in the first half of the document. The booklet reviews the process of assessing the school, its program, and its image; identifying the financial, material,…

  20. Flow management and fish density regulate salmonid recruitment and adult size in tailwaters across western North America.

    PubMed

    Dibble, Kimberly L; Yackulic, Charles B; Kennedy, Theodore A; Budy, Phaedra

    2015-12-01

    Rainbow and brown trout have been intentionally introduced into tailwaters downriver of dams globally and provide billions of dollars in economic benefits. At the same time, recruitment and maximum length of trout populations in tailwaters often fluctuate erratically, which negatively affects the value of fisheries. Large recruitment events may increase dispersal downriver where other fish species may be a priority (e.g., endangered species). There is an urgent need to understand the drivers of trout population dynamics in tailwaters, in particular the role of flow management. Here, we evaluate how flow, fish density, and other physical factors of the river influence recruitment and mean adult length in tailwaters across western North America, using data from 29 dams spanning 1-19 years. Rainbow trout recruitment was negatively correlated with high annual, summer, and spring flow and dam latitude, and positively correlated with high winter flow, subadult brown trout catch, and reservoir storage capacity. Brown trout recruitment was negatively correlated with high water velocity and daily fluctuations in flow (i.e., hydropeaking) and positively correlated with adult rainbow trout catch. Among these many drivers, rainbow trout recruitment was primarily correlated with high winter flow combined with low spring flow, whereas brown trout recruitment was most related to high water velocity. The mean lengths of adult rainbow and brown trout were influenced by similar flow and catch metrics. Length in both species was positively correlated with high annual flow but declined in tailwaters with high daily fluctuations in flow, high catch rates of conspecifics, and when large cohorts recruited to adult size. Whereas brown trout did not respond to the proportion of water allocated between seasons, rainbow trout length increased in rivers that released more water during winter than in spring. Rainbow trout length was primarily related to high catch rates of conspecifics

  1. Ulcer disease of trout

    USGS Publications Warehouse

    Fish, F.F.

    1934-01-01

    During the summer of 1933, lesions of a disease were noted among some fingerling brook, rainbow, blackspotted, and lake trout at the Cortland (New York) trout hatchery. Although these lesions bore a marked superficial resemblance to those of furunculosis, they were sufficiently atypical to warrant further investigation. A more detailed examination of the lesions proved them to be of a distinct disease, which for lack of a better name is herein called "ulcer disease," for the lesions closely resemble those described by Calkins (1899) under this name. Because of the marked resemblance to furunculosis, ulcer disease has not been generally recognized by trout culturists, and any ulcer appearing on fish has been ascribed by them to furunculosis without further question.

  2. Causes of declining survival of lake trout stocked in U.S. waters of Lake Superior in 1963-1986

    USGS Publications Warehouse

    Hansen, Michael J.; Ebener, Mark P.; Schorfhaar, Richard G.; Schram, Stephen T.; Schreiner, Donald R.; Selgeby, James H.; Taylor, William W.

    1996-01-01

    Survival of the 1963-1982 year-classes of stocked yearling lake trout Salvelinus namaycush declined significantly over time in Lake Superior. To investigate possible causes of this decline, a Ricker model of stock-recruitment was used to describe the catch per effort (CPE) of age-7 stocked lake trout in the Michigan, Minnesota, and Wisconsin waters of Lake Superior as functions of the numbers of yearlings stocked 6 years earlier (an index of density dependence), the density (CPE) of wild adult lake trout (an index of predation), and large-mesh (a?Y 114-mm stretch-measure) gill-net fishing effort (an index of fishing mortality). Declining CPE of stocked lake trout in Michigan and Wisconsin was significantly associated with increasing large-mesh gillnet fishing effort. Declining CPE of stocked lake trout in Minnesota was significantly associated with increasing density of wild lake trout. Declining survival of stocked lake trout may therefore have been caused by increased mortality in large-mesh gill-net fisheries in Michigan and Wisconsin, and by predation by wild lake trout that recently recolonized the Minnesota area. We recommend that experimental management be pursued to determine the relative importance of large-mesh gillnet fishing effort and of predation by wild lake trout on the survival of stocked lake trout in U.S. waters of Lake Superior.

  3. Larval long-toed salamanders incur nonconsumptive effects in the presence of nonnative trout

    USGS Publications Warehouse

    Kenison, Erin K.; Litt, Andrea R.; Pilliod, David; McMahon, Thomas E.

    2016-01-01

    Predators can influence prey directly through consumption or indirectly through nonconsumptive effects (NCEs) by altering prey behavior, morphology, and life history. We investigated whether predator-avoidance behaviors by larval long-toed salamanders (Ambystoma macrodactylum) in lakes with nonnative trout result in NCEs on morphology and development. Field studies in lakes with and without trout were corroborated by experimental enclosures, where prey were exposed only to visual and chemical cues of predators. We found that salamanders in lakes with trout were consistently smaller than in lakes without trout: 38% lower weight, 24% shorter body length, and 29% shorter tail length. Similarly, salamanders in protective enclosures grew 2.9 times slower when exposed to visual and olfactory trout cues than when no trout cues were present. Salamanders in trout-free lakes and enclosures were 22.7 times and 1.48 times, respectively, more likely to metamorphose during the summer season than those exposed to trout in lakes and/or their cues. Observed changes in larval growth rate and development likely resulted from a facultative response to predator-avoidance behavior and demonstrate NCEs occurred even when predation risk was only perceived. Reduced body size and growth, as well as delayed metamorphosis, could have ecological consequences for salamander populations existing with fish if those effects carry-over into lower recruitment, survival, and fecundity.

  4. Lack of selection for resistance to whirling disease among progeny of Colorado River rainbow trout

    USGS Publications Warehouse

    Ryce, E.K.N.; Zale, A.V.; Nehring, R.B.

    2001-01-01

    We compared the resistance to whirling disease of two groups of Colorado River rainbow trout Oncorhynchus mykiss and a domestic strain of rainbow trout in a controlled laboratory challenge. These three groups represented the progeny of wild rainbow trout known to have recruited (1) during the early years of infestation by Myxobolus cerebralis of the Colorado River or (2) before the presence of M. cerebralis in the system and (3) the Erwin strain of rainbow trout. The severity of whirling disease in each group was dependent on the dose of triactinomyxons of M. cerebralis to which the fish were exposed. Microscopic lesions and spore counts both increased with increasing parasite dose. Survival of the progeny of Colorado fish that recruited before the presence of M. cerebralis in the system was significantly less than was that of the domestic fish exposed to 0 and 1,000 triactinomyxons/fish. The parents that recruited to the system before the presence of M. cerebralis were considerably older than were those used for our domestic strain; this difference in parent age probably resulted in the difference in survival because egg quality decreases with age in rainbow trout. There was no difference in microscopic lesions, spore counts, or swimming performance among the three groups of rainbow trout when exposed at the same parasite level, indicating that there was no difference in resistance to whirling disease among these groups of fish.

  5. Management and Breeding Soundness of Mature Bulls.

    PubMed

    Palmer, Colin W

    2016-07-01

    Mature bulls must be fed a balanced ration, vaccinated appropriately, and undergo a breeding soundness evaluation to ensure they meet what is required of a short, but intense breeding season. To be classified as a satisfactory potential breeder, minimum standards for physical soundness, scrotal circumference, sperm motility, and sperm morphology must be achieved using an accepted bull-breeding soundness evaluation format. Sperm production requires approximately 70 days. Heat and stress are the most common insults to spermatogenesis, causing an increase in morphologic abnormalities with obesity-associated scrotal fat accumulation being the most frequent cause of elevated testicular temperature in mature bulls.

  6. Density-independent survival of wild lake trout in the Apostle Islands area of Lake Superior

    USGS Publications Warehouse

    Bronte, Charles R.; Schram, Stephen T.; Selgeby, James H.; Swanson, Bruce L.

    1995-01-01

    The lake trout (Salvelinus namaycush) stock at Gull Island Shoal in western Lake Superior was one of only a few stocks of lean lake trout in the Great Lakes that survived overfishing and predation by the sea lamprey (Petromyzon marinus). Since the mid 1960s, the abundance of wild recruits measured at age 0 and the number of age-7 to -11 wild fish recruited to the fishable stock have increased. We used the Varley-Gradwell method to test for density-dependent survival between these life stages. Survival from age-0 to ages 7–11 was not affected by increasing density, which suggests that further increases in recruitment and stock size are still possible. We suggest that testing for the existence of density-dependent survival can be used to indicate when lake trout populations are rehabilitated.

  7. Bull breeding soundness evaluation in Southern Africa.

    PubMed

    Irons, P C; Nöthling, J O; Bertschinger, H J

    2007-10-01

    The motivation for and process leading up to the publication of a new bull breeding soundness certification standard endorsed by the South African Veterinary Association is described. The veterinary certificate of bull breeding soundness and explanatory notes and minimum standards are shown. The first component of the certificate is a declaration by the veterinarian that the bull complies with the minimum standards set for examinations for the selected purpose, these being for use as a natural service sire, as a donor of semen for distribution, and for insurance purposes. This is followed by the details of the bull and owner, and a list of the recommended examinations and tests for the bull with provision for which were performed. Certificates are available in book form with the explanatory notes and minimum standards on the reverse, and a carbon copy which remains in the book. The clarity and ease of completion of the document are regarded as being positive features. Bulls are either classified as breeding sound or not, with no actual parameters indicated on the document and no certificate issued for those which do not meet the set criteria. Contact details of the parties involved are shown on the certificate to allow for communication as a means of avoiding disputes.

  8. An assessment of dairy herd bulls in southern Australia: 1. Management practices and bull breeding soundness evaluations.

    PubMed

    Hancock, A S; Younis, P J; Beggs, D S; Mansell, P D; Stevenson, M A; Pyman, M F

    2016-12-01

    In the pasture-based, seasonally calving dairy herds of southern Australia, the mating period usually consists of an initial artificial insemination period followed by a period of natural service using herd bulls. Bull breeding soundness evaluations (BBSE) were performed on 256 bulls from 32 dairy herds in southwest Victoria, using guidelines produced by the Australian Cattle Veterinarians, before and immediately after a single natural mating period. At the same time, herd managers were questioned regarding the management of the bulls. The objectives of this study were to describe the management practices of dairy herd bulls; to describe the causes of increased risk of reduced fertility in dairy herd bulls, as measured by a standard BBSE; and to describe the reasons for bull removal by herd managers during mating. At the premating BBSE, 19.5% of bulls were classified as high risk of reduced fertility, mostly due to physical abnormalities and reduced semen quality. At the postmating BBSE, 36.5% of bulls were classified as high risk of reduced fertility, mostly due to physical abnormalities, primarily lameness. Of the bulls used, 15.9% were removed from normal mating use by the herd manager, predominantly due to lameness and injuries. A premating BBSE is recommended in dairy herd bulls to identify bulls at risk of reduced fertility. Lameness is the most common problem in dairy herd bulls during the natural mating period, and risk factors associated with lameness in these bulls should be identified to better manage herd bulls.

  9. Distribution of Brook Trout and Their Food Sources in Meadow vs. Wooded Areas of Sierra Nevada Headwater Streams

    NASA Astrophysics Data System (ADS)

    Basile, N. J.; Blumenshine, S.

    2005-05-01

    Stocked eastern brook trout are now well established in historically fishless, small headwater streams in the Sierra Nevada. Although non-native, brook trout have maintained healthy populations since stocking ended 60-80 years ago. Our primary research question was whether brook trout distribution and feeding ecology is influenced by variation in headwater stream habitats and food sources. Stream habitat characteristics and trout demographic data were collected during June and August 2004 from four forested and three meadow sites among five tributaries to Bull Creek in the Sierra Nevada. Both mean fish mass and total fish biomass were greater in forested versus meadow reaches. Macroinvertebrate drift rate did not differ between meadow versus wooded reaches, but were greater in June than August. However, despite higher fish biomass, trout in forests apparently selected prey from drift, whereas trout diets in meadows reflected availability in drift. The results of this research will ultimately be used in a larger, collaborative, whole-ecosystem study conducted by the USDA-Forest Service addressing how current forest management practices affect stream ecosystems.

  10. Winter Habitats of Atlantic Salmon, Brook Trout, Brown Trout and Rainbow Trout: A Literature Review

    DTIC Science & Technology

    1989-10-01

    TERMS (Continue on reverse if necessary and identify by block number) FIELD GROUP SUB-GROUP Ice conditions Trout River ice Winter habitat Salmon 19...did only 6 cm of water depth was required for travel, not observe trout hiding in the substrate in the winter in the Credit River , although this has...10°C, as measured in Maine rivers using the on the winter habitat of brown trout fry in the standard technique dsecribed by Terhune (1958) Credit

  11. Examining indirect effects of lake trout recovery

    EPA Science Inventory

    With the recovery of lake trout populations in Lake Superior, there are indications of decreased forage fish abundance and density-dependence in lake trout. In Lake Superior, lean lake trout historically occupied depths < 60 m, and siscowet lake trout occupied depths > 60 m...

  12. An ecological risk assessment of the acute and chronic effects of the herbicide clopyralid to rainbow trout (Oncorhynchus mykiss).

    PubMed

    Fairchild, J F; Allert, A L; Feltz, K P; Nelson, K J; Valle, J A

    2009-11-01

    Clopyralid (3,6-dichloro-2-pyridinecarboxylic acid) is a pyridine herbicide frequently used to control invasive, noxious weeds in the northwestern United States. Clopyralid exhibits low acute toxicity to fish, including the rainbow trout (Oncorhynchus mykiss) and the threatened bull trout (Salvelinus confluentus). However, there are no published chronic toxicity data for clopyralid and fish that can be used in ecological risk assessments. We conducted 30-day chronic toxicity studies with juvenile rainbow trout exposed to the acid form of clopyralid. The 30-day maximum acceptable toxicant concentration (MATC) for growth, calculated as the geometric mean of the no observable effect concentration (68 mg/L) and the lowest observable effect concentration (136 mg/L), was 96 mg/L. No mortality was measured at the highest chronic concentration tested (273 mg/L). The acute:chronic ratio, calculated by dividing the previously published 96-h acutely lethal concentration (96-h ALC(50); 700 mg/L) by the MATC was 7.3. Toxicity values were compared to a four-tiered exposure assessment profile assuming an application rate of 1.12 kg/ha. The Tier 1 exposure estimation, based on direct overspray of a 2-m deep pond, was 0.055 mg/L. The Tier 2 maximum exposure estimate, based on the Generic Exposure Estimate Concentration model (GEENEC), was 0.057 mg/L. The Tier 3 maximum exposure estimate, based on previously published results of the Groundwater Loading Effects of Agricultural Management Systems model (GLEAMS), was 0.073 mg/L. The Tier 4 exposure estimate, based on published edge-of-field monitoring data, was estimated at 0.008 mg/L. Comparison of toxicity data to estimated environmental concentrations of clopyralid indicates that the safety factor for rainbow trout exposed to clopyralid at labeled use rates exceeds 1000. Therefore, the herbicide presents little to no risk to rainbow trout or other salmonids such as the threatened bull trout.

  13. Trout in the Classroom

    NASA Astrophysics Data System (ADS)

    Heath, Thomas

    2014-05-01

    Trout in the Classroom (TIC) is a conservation-oriented environmental education program for elementary, middle, and high school students. During the year each teacher tailors the program to fit his or her curricular needs. Therefore, each TIC program is unique. TIC has interdisciplinary applications in science, social studies, mathematics, language arts, fine arts, and physical education. In the program, students and teachers raise trout from fertilized eggs supplied by Virginia Department of Game and Inland Fisheries (VGIF) hatcheries, in aquariums equipped with special chillers designed to keep the water near 50 degrees F. The students make daily temperature measurements, and monitor pH, dissolved oxygen, conductivity, and ammonia levels. They record their data, plot trends, and make sure that the water quality is sufficient to support trout development. The fingerlings, which hatch in late October, are almost an inch and a half long by mid-January. And towards the end of the school year, students will release the fry into VGIF approved watersheds. TIC programs have been in place all across the country for more than 20 years, and are the result of numerous collaborations between teachers, volunteers, government agencies, and local organizations like Trout Unlimited. The programs were designed specifically for teachers who wanted to incorporate more environmental education into their curriculum. While the immediate goal of Trout in the Classroom is to increase student knowledge of water quality and cold water conservation, its long-term goal is to reconnect an increasingly urbanized population of youth to the system of streams, rivers, and watersheds that sustain them. Successful programs have helped: connect students to their local environments and their local watersheds; teach about watershed health and water quality, and; get students to care about fish and the environment. In Virginia, the TIC program is now in its 8th year. Over the past year, the program

  14. Flow management and fish density regulate salmonid recruitment and adult size in tailwaters across western North America

    USGS Publications Warehouse

    Dibble, Kimberly L.; Yackulic, Charles B.; Kennedy, Theodore A.; Budy, Phaedra E.

    2015-01-01

    The mean lengths of adult rainbow and brown trout were influenced by similar flow and catch metrics. Length in both species was positively correlated with high annual flow but declined in tailwaters with high daily fluctuations in flow, high catch rates of conspecifics, and when large cohorts recruited to adult size. Whereas brown trout did not respond to the proportion of water allocated between seasons, rainbow trout length increased in rivers that released more water during winter than in spring. Rainbow trout length was primarily related to high catch rates of conspecifics, whereas brown trout length was mainly related to large cohorts recruiting to the adult size class. Species-specific responses to flow management are likely attributable to differences in seasonal timing of key life history events such as spawning, egg hatching, and fry emergence.

  15. Thiamine deficiency effects on the vision and foraging ability of lake trout fry.

    PubMed

    Carvalho, Paulo S M; Tillitt, Donald E; Zajicek, James L; Claunch, Rachel A; Honeyfield, Dale C; Fitzsimons, John D; Brown, Scott B

    2009-12-01

    The exact causes of the historical recruitment failures of Great Lakes lake trout Salvelinus namaycush are unknown. Thiamine deficiency has been associated with neurological abnormalities in lake trout that lead to early mortality syndrome (EMS) in salmonine swim-up fry, and EMS-related mortality at the swim-up stage is a factor that contributes to the reproductive failure of lake trout populations in the Great Lakes. The potential for adverse effects of thiamine deficiency beyond the swim-up stage is unknown. We investigated the effects of low egg thiamine on behavioral functions in young, post-swim-up lake trout fry. The behavioral endpoints included visual acuity and prey capture rates in the same groups of lake trout fry from each family. Low-thiamine eggs were produced by feeding lake trout broodstock diets entailing thiaminase activity. The thiamine content of the spawned eggs ranged from 0.3 to 26.1 nmol/g. Both visual acuity and prey capture rates were affected by the thiamine content of the eggs. The visual acuity of lake trout was severely affected by low egg thiamine, mainly at thiamine concentrations below the threshold of 0.8 nmol/g but also at higher concentrations in field-collected eggs. Feeding was also reduced with low egg thiamine content. The reduction of prey capture rates was dramatic below 0.8 nmol/g and less dramatic, but still significant, in a portion of the families with egg thiamine concentrations of less than 5.0 nmol/g from both laboratory and field samples. Approximately one-third of the latter families had reduced feeding rates. Deficits in visual acuity may be part of the mechanism leading to decreased feeding rates in these fry. The effects of low egg thiamine on both of the behavioral endpoints studied increase the risk of low recruitment rates in Great Lakes lake trout populations.

  16. 4. Photocopy from James H. Bull, Records of the Descendants ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Photocopy from James H. Bull, Records of the Descendants of John and Elizabeth Bull, 1919 WEST AND NORTH ELEVATIONS - Mount Pleasant, Bulltown Road (East Nantmeal Township), East Nantmeal, Chester County, PA

  17. 58. DETAIL OF PINION AND BULL GEARS: Detail view towards ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    58. DETAIL OF PINION AND BULL GEARS: Detail view towards northeast of the pinion and bull gears of the winding machinery. - San Francisco Cable Railway, Washington & Mason Streets, San Francisco, San Francisco County, CA

  18. Broad-scale patterns of Brook Trout responses to introduced Brown Trout in New York

    USGS Publications Warehouse

    McKenna, James E.; Slattery, Michael T.; Kean M. Clifford,

    2013-01-01

    Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta are valuable sport fish that coexist in many parts of the world due to stocking introductions. Causes for the decline of Brook Trout within their native range are not clear but include competition with Brown Trout, habitat alteration, and repetitive stocking practices. New York State contains a large portion of the Brook Trout's native range, where both species are maintained by stocking and other management actions. We used artificial neural network models, regression, principal components analysis, and simulation to evaluate the effects of Brown Trout, environmental conditions, and stocking on the distribution of Brook Trout in the center of their native range. We found evidence for the decline of Brook Trout in the presence of Brown Trout across many watersheds; 22% of sampled reaches where both species were expected to occur contained only Brown Trout. However, a model of the direct relationship between Brook Trout and Brown Trout abundance explained less than 1% of data variation. Ordination showed extensive overlap of Brook Trout and Brown Trout habitat conditions, with only small components of the hypervolume (multidimensional space) being distinctive. Subsequent analysis indicated higher abundances of Brook Trout in highly forested areas, while Brown Trout were more abundant in areas with relatively high proportions of agriculture. Simulation results indicated that direct interactions and habitat conditions were relatively minor factors compared with the effects of repeated stocking of Brown Trout into Brook Trout habitat. Intensive annual stocking of Brown Trout could eliminate resident Brook Trout in less than a decade. Ecological differences, harvest behavior, and other habitat changes can exacerbate Brook Trout losses. Custom stocking scenarios with Brown Trout introductions at relatively low proportions of resident Brook Trout populations may be able to sustain healthy populations of both

  19. Initial analysis of sperm DNA methylome in Holstein bulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aberrant DNA methylation patterns have been associated with abnormal semen parameters, idiopathic male infertility and early embryonic loss in mammals. Using Holstein bulls with high (Bull1) or low (Bull2) fertility rates, we created two representative sperm DNA methylomes at a single-base resolutio...

  20. Phthalate biotransformation by rainbow trout

    SciTech Connect

    Barron, M.G.; Hayton, W.L.

    1994-12-31

    The biotransformation of di(2-ethylhexyl)phthalate (DEHP) was studied in rainbow trout because DEHP bioconcentration is limited by metabolism. Biological fluids were collected following intravascular administration. Methylesterified metabolites were identified using rodent-derived standards and nonlinear gradient elution HPLC; metabolites were confirmed by gas chromatography. Similarities between the biotransformation of DEHP by rainbow trout and mammalian species included: (1) mono-2-ethylhexyl phthalate (MEHP) appeared to be the obligatory first step in DEHP metabolism; (2) the phthalate ring was not oxidized; (3) phthalic acid was a minor metabolite; and (4) several metabolites contained multiple oxidations of the 2-ethylhexyl moiety of MEHP. No metabolites unique to rainbow trout were identified. However, fewer oxidized metabolites were identified in rainbow trout than in mammalian species, possibly due to limited mitochondrial metabolism of MEHP in rainbow trout. The amount of biliary MEHP glucuronide after intravascular administration of DEHP was substantially less than reported in rainbow trout exposed to DEHP via the water. The results confirmed that DEHP metabolism in rainbow trout proceeds by initial rapid formation of MEHP, followed by excretion or extensive oxidation by microsomal P450.

  1. Dworshak Reservoir Investigations: Trout, Bass and Forage Species, 1987 Annual Report.

    SciTech Connect

    Statler, David P.

    1988-05-01

    Dworshak Dam and Reservoir is a Corps of Engineers facility located on the North Fork Clearwater River 3.2 km upstream from the Mainstem Clearwater confluence. Since initial filling in 1971, conversion of 87 km of river habitat to a 6644 hectare impoundment has had a profound influence on resident fisheries. The Nez Perce Tribe and the Idaho Department of Fish and Game (IDFG) entered into separate intergovernmental agreements with the Bonneville Power Administration in a cooperative effort to study these impacts. The kokanee Oncorhynchus nerka assessment is included in the IDFG agreement, and is not addressed in this report. This project pertains primarily to rainbow trout Salmo gairdneri, smallmouth bass (Micropterus dolomieui), and forage species. For the period November 1987 through February 1988, an estimated 4339 angler-hours were expended to catch 430 rainbow trout. An estimated 20 bull trout Salvelinus confluentus, 4 smallmouth bass, and 4 suckers Catostomus spp. were also caught. Catch rates were generally poor through the period, at .091 fish per hour for all species combined (excluding kokanee). Shasta strain hatchery rainbow trout were dominant in the creel, comprising 53.9 percent of the catch, although this strain was last planted in the reservoir in June 1986. Bank anglers caught a higher percentage (93.5 percent) of the total catch of Shasta strain rainbows than Kamloops strain rainbows (33.3 percent). 11 refs., 4 figs., 6 tabs.

  2. Effects of extreme floods on trout populations and fish communities in a Catskill Mountain river

    USGS Publications Warehouse

    George, Scott D.; Baldigo, Barry P.; Smith, Alexander J; Robinson, George

    2015-01-01

    5. Late summer floods may be less damaging to stream fish communities than winter or spring floods as spawning activity is negligible and early life stages of many species are generally larger and less susceptible to displacement and mortality. Additionally, post-flood conditions may be advantageous for brown trout recruitment.

  3. Lake trout population dynamics at Drummond Island Refuge in Lake Huron: Implications for future rehabilitation

    USGS Publications Warehouse

    Madenjian, C.P.; Ebener, M.P.; Desorcie, T.J.

    2008-01-01

    The Drummond Island Refuge (DIR) was established in 1985 as part of the rehabilitation effort for lake trout Salvelinus namaycush in Lake Huron. Since then, several strains of hatchery-reared lake trout have been stocked annually at the DIR. An intensive lampricide treatment of the St. Marys River during 1998-2001 was expected to lower the abundance of sea lamprey Petromyzon marinus within the DIR by 2000. We conducted annual gill-net surveys during spring and fall to evaluate the performance of each of the strains of lake trout as well as that of the entire lake trout population (all strains pooled) in the DIR during 1991-2005. The criteria to evaluate performance included the proportion of "wild" fish within the population, spawner density, adult survival, growth, maturity, and wounding rate by sea lampreys. Wild lake trout did not recruit to the adult population to any detectable degree. During 1991-2005, the average density of spawning lake trout appeared to be marginally sufficient to initiate a self-sustaining population. Survival of the Seneca Lake (SEN) strain of lake trout was significantly higher than that of the Superior-Marquette (SUP) strain, in part because of the higher sea-lamprey-induced mortality suffered by the SUP strain. However, other factors were also involved. Apparently SUP fish were more vulnerable to fishing conducted in waters near the refuge boundaries than SEN fish. The St. Marys River treatment appeared to be effective in reducing the sea lamprey wounding rate on SEN fish. We recommend that the stocking of SEN lake trout in the DIR, control of sea lampreys in the St. Marys River, and reduction of commercial fishery effort in waters near the DIR be maintained. ?? Copyright by the American Fisheries Society 2008.

  4. Performance, growth, and maturity of Nellore bulls.

    PubMed

    Costa e Silva, Luiz Fernando; Valadares Filho, Sebastião de Campos; Detmann, Edenio; Rotta, Polyana Pizzi; Zanetti, Diego; Villadiego, Faider Alberto Castaño; Pellizzoni, Samantha Gusmão; Pereira, Rafael Moura Guimarães

    2013-03-01

    The objectives of this study were to evaluate the dry matter intake (DMI), digestibility, average daily gain (ADG), microbial efficiency, empty body weight (EBW) gain, and body composition of Nellore bulls. Additionally, Nellore bull maturity was estimated, and the prediction equation for DMI, suggested by the Brazilian nutrient requirements system (BR CORTE; Azevêdo et al. 2010), was evaluated. Thirty-three Nellore bulls, with a mean initial weight of 259 ± 25 kg and age of 14 ± 1 months, were used in this study. Five animals were slaughtered at the beginning of the experiment (control group), and the remaining 28 were divided into 4 groups, each slaughtered at 42-day intervals. Their diet was composed of corn silage and concentrate (55:45). The power model was used to estimate muscle tissue, bone tissue, crude protein (CP), mineral matter (MM), and water present in the empty body, while the exponential model was used to estimate adipose tissue and ether extract (EE) present in the empty body. When expressed in kilograms per day, differences were observed (P < 0.05) only for the intake of EE and neutral detergent fiber as a function of feedlot time periods. Although there was a difference in relation to nutrient intake, it did not affect (P > 0.05) digestibility, with the exception of EE digestibility. The equation suggested by BR CORTE correctly estimates the DMI of Nellore bulls. ADG was not affected (P > 0.05) by time spent in the feedlot. No differences were observed (P > 0.05) for microbial efficiency; a mean value of 142 g microbial crude protein/kg total digestible nutrients was achieved. The muscle and bone tissues, CP, MM, and water present in the empty body increased as the animal grew, although at a lower rate. The adipose tissue and EE present in the empty body increased their deposition rate when the animal reached its mature weight. Maturity is defined as when an animal reaches 22 % EE in the empty body, which

  5. Status of lake trout rehabilitation on Six Fathom Bank and Yankee Reef in Lake Huron

    USGS Publications Warehouse

    Madenjian, Charles P.; DeSorcie, Timothy J.; McClain, Jerry R.; Woldt, Aaron P.; Holuszko, Jeffrey D.; Bowen, Charles A.

    2004-01-01

    Six Fathom Bank, an offshore reef in the central region of Lake Huron's main basin, was stocked annually with hatchery-reared lake trout Salvelinus namaycush during 1985–1998, and nearby Yankee Reef was stocked with hatchery-reared lake trout in 1992, 1997, and annually during 1999–2001. We conducted gill-net surveys during spring and fall to evaluate performances of each of the various strains of lake trout, as well as the performance of the entire lake trout population (all strains pooled), on these two offshore reefs during 1992–2000. Criteria to evaluate performance included the proportion of “wild” fish within the population, spawner density, adult survival, growth, maturity, and wounding rate by sea lamprey Petromyzon marinus. Although naturally reproduced age-0 lake trout fry were caught on Six Fathom Bank and Yankee Reef, wild lake trout did not recruit to the adult population to any detectable degree. The density of spawning lake trout on Six Fathom Bank (>100 fish/305 m of gill net) during 1995–1998 appeared to be sufficiently high to initiate a self-sustaining population. However, annual mortality estimates for all lake trout strains pooled from catch curve analyses ranged from 0.48 to 0.62, well exceeding the target level of 0.40 suggested for lake trout rehabilitation. Annual mortality rate for the Seneca Lake strain (0.34) was significantly lower than that for the Superior–Marquette (0.69) and Lewis Lake (0.69) strains. This disparity in survival among strains was probably attributable to the lower sea-lamprey-induced mortality experienced by the Seneca Lake strain. The relatively high mortality experienced by adult lake trout partly contributed to the lack of successful natural recruitment to the adult population on these offshore reefs, but other factors were probably also involved. We recommend that both stocking of the Seneca Lake strain and enhanced efforts to reduce sea lamprey abundance in Lake Huron be continued.

  6. 33 CFR 117.337 - Trout River.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Trout River. 117.337 Section 117... OPERATION REGULATIONS Specific Requirements Florida § 117.337 Trout River. The draw of the CSX Railroad Bridge across the Trout River, mile 0.9 at Jacksonville, operates as follows: (a) The bridge is...

  7. 33 CFR 117.337 - Trout River.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Trout River. 117.337 Section 117... OPERATION REGULATIONS Specific Requirements Florida § 117.337 Trout River. The draw of the CSX Railroad Bridge across the Trout River, mile 0.9 at Jacksonville, operates as follows: (a) The bridge is...

  8. 33 CFR 117.337 - Trout River.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Trout River. 117.337 Section 117... OPERATION REGULATIONS Specific Requirements Florida § 117.337 Trout River. The draw of the CSX Railroad Bridge across the Trout River, mile 0.9 at Jacksonville, operates as follows: (a) The bridge is...

  9. 33 CFR 117.337 - Trout River.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Trout River. 117.337 Section 117... OPERATION REGULATIONS Specific Requirements Florida § 117.337 Trout River. The draw of the CSX Railroad Bridge across the Trout River, mile 0.9 at Jacksonville, operates as follows: (a) The bridge is...

  10. 33 CFR 117.337 - Trout River.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Trout River. 117.337 Section 117... OPERATION REGULATIONS Specific Requirements Florida § 117.337 Trout River. The draw of the CSX Railroad Bridge across the Trout River, mile 0.9 at Jacksonville, operates as follows: (a) The bridge is...

  11. Patterns of hybridization of nonnative cutthroat trout and hatchery rainbow trout with native redband trout in the Boise River, Idaho

    USGS Publications Warehouse

    Neville, Helen M.; Dunham, Jason B.

    2011-01-01

    Hybridization is one of the greatest threats to native fishes. Threats from hybridization are particularly important for native trout species as stocking of nonnative trout has been widespread within the ranges of native species, thus increasing the potential for hybridization. While many studies have documented hybridization between native cutthroat trout Oncorhynchus clarkii and nonnative rainbow trout O. mykiss, fewer have focused on this issue in native rainbow trout despite widespread threats from introductions of both nonnative cutthroat trout and hatchery rainbow trout. Here, we describe the current genetic (i.e., hybridization) status of native redband trout O. mykiss gairdneri populations in the upper Boise River, Idaho. Interspecific hybridization was widespread (detected at 14 of the 41 sampled locations), but high levels of hybridization between nonnative cutthroat trout and redband trout were detected in only a few streams. Intraspecific hybridization was considerably more widespread (almost 40% of sampled locations), and several local populations of native redband trout have been almost completely replaced with hatchery coastal rainbow trout O. mykiss irideus; other populations exist as hybrid swarms, some are in the process of being actively invaded, and some are maintaining genetic characteristics of native populations. The persistence of some redband trout populations with high genetic integrity provides some opportunity to conserve native genomes, but our findings also highlight the complex decisions facing managers today. Effective management strategies in this system may include analysis of the specific attributes of each site and population to evaluate the relative risks posed by isolation versus maintaining connectivity, identifying potential sites for control or eradication of nonnative trout, and long-term monitoring of the genetic integrity of remaining redband trout populations to track changes in their status.

  12. Reestablishing a spawning population of lake trout in Lake Superior with fertilized eggs in artificial turf incubators

    USGS Publications Warehouse

    Bronte, Charles R.; Schram, Stephen T.; Selgeby, James H.; Swanson, Bruce L.

    2002-01-01

    Fertilized eggs from lake trout Salvelinus namaycush were placed in artificial turf incubators and deployed on Devils Island Shoal, Lake Superior, in an attempt to reestablish a spawning population on this once important spawning area. Efficacy was measured by the changes in catch rates, age composition, and origin of adult lake trout returning to the shoal in the fall in subsequent years. The abundance of lake trout spawners without fin clips, which implies that these fish hatched in the lake, increased throughout the sampling period, whereas the abundance of hatchery-reared fish (indicated by one or more fin clips) stocked for restoration purposes remained low. Year-class-specific stock-recruitment analysis suggested that the recruitment of unclipped spawners was related to the number of eggs planted in previous years rather than to spawning by the few adult lake trout visiting the reef. Increases in adult fish at Devils Island Shoal were independent of trends at adjacent sites, where unclipped spawner abundances remained low. Enhanced survival to hatch and apparent site imprinting of young lake trout make this technique a viable alternative to stocking fingerling and yearling lake trout to reestablish spawning populations on specific sites in the Great Lakes.

  13. Verminous myelitis in a pit bull puppy.

    PubMed

    Snook, Eric R; Baker, David G; Bauer, Rudy W

    2009-05-01

    A 10-week-old, male pit bull dog presented to the referring veterinarian with hind limb paresis and epaxial muscle atrophy. No spinal lesions were identified at gross necropsy; however, histologically there was marked granulomatous myelitis in the spinal cord between T13 and L2 with occasional, intralesional nematode larvae. Based on morphologic characteristics, the nematode larvae were identified as Strongyloides spp., possibly Strongyloides stercoralis.

  14. Mauling by pit bull terriers: case report.

    PubMed

    Baack, B R; Kucan, J O; Demarest, G; Smoot, E C

    1989-04-01

    A child with extensive soft-tissue defects following an attack by four pit bull terriers is presented. Some future procedures are required and she will have a permanent gait disability. The multidisciplinary management of this patient is described. The escalating problem of dog attacks in the United States is discussed. It is hoped that increased physician and public awareness will expedite the enactment and enforcement of effective vicious-dog legislation.

  15. Bull heading to kill live gas wells

    SciTech Connect

    Oudeman, P.; Avest, D. ter; Grodal, E.O.; Asheim, H.A.; Meissner, R.J.H.

    1994-12-31

    To kill a live closed-in gas well by bull heading down the tubing, the selected pump rate should be high enough to ensure efficient displacement of the gas into the formation (i.e., to avoid the kill fluid bypassing the gas). On the other hand, the pressures that develop during bull heading at high rate must not exceed wellhead pressure rating, tubing or casing burst pressures or the formation breakdown gradient, since this will lead, at best, to a very inefficient kill job. Given these constraints, the optimum kill rate, requited hydraulic horsepower, density and type of kill fluids have to be selected. For this purpose a numerical simulator has been developed, which predicts the sequence of events during bull heading. Pressures and flow rates in the well during the kill job are calculated, taking to account slip between the gas and kill fluid, hydrostatic and friction pressure drop, wellbore gas compression and leak-off to the formation. Comparison with the results of a dedicated field test demonstrates that these parameters can be estimated accurately. Example calculations will be presented to show how the simulator can be used to identify an optimum kill scenario.

  16. USAR Recruiting Success Factors.

    DTIC Science & Technology

    1987-12-01

    recruiters. Conventional multi. * variate statistical techniques have not prov ed-adequate in identifying successful recruiters, largely because of the...statistical techniques to the problem of identifying the relative importance of factors affecting recruiter success. Me t hod This study applies a...recruiters; background characteristics, suggestions about recruiter training, the value of various prospecting and selling techniques , workload, attitudes

  17. An evaluation of trout culture

    USGS Publications Warehouse

    1940-01-01

    In an evaluation of the efficiency of trout culture, the author presents a detailed analysis of complete loss records from 288 individual lots of trout at twenty-two hatcheries in the western United States. Summarized data are given to show the percentage loss of eggs, fry, and fingerlings by progressive one-half inch size groups. The accumulative percentage loss is also included to indicate the losses, under average hatchery conditions, between the egg stage and each successive size-group. These data cover the individual species of trout commonly reared in hatcheries; summarized data are given also for all species combined. A brief discussion of hatchery losses, natural losses, and the cost of artificial propagation is included.

  18. Furunculosis in wild trout

    USGS Publications Warehouse

    Fish, F.F.

    1937-01-01

    Furunculosis, or as it has been more appropiately termed, "fish septicemia," is a disease primarily affecting salmon and trout. It is caused by the invasion and growth of Bacterium salmonicida Emmerich and Weibel, a Gram negative, non-spore forming, diplobacterium belonging to the family Bacteriaceae Cohn. After gaining entrance to the host, presumably by way of the digestive tract, the organism is spread by the blood stream and produces focal necrosis and subsequent liquefaction throughout the tissues. The more conspicuous gross lesions are those of the body musculature, characterized by the formation of deep seated "boils" or "bloody blotches"—blisters filled with liquefied muscle tissue and blood. Under favorable conditions, the muscle lesions enlarge rapidly and eventually rupture through the skin producing a characteristic, ragged, deep, undermining type of ulcer. Although the muscle lesions are most conspicuous, essentially the same progressive necrosis and liquefaction are to be found throughout the internal organs, particularly in the spleen and kidneys. The host has no adequate defense mechanism against this disease and no verified recovery from furunculosis has ever been recorded. Cases may be arrested by low water temperatures or other adverse factors, only to break out with renewed vigor when conditions again become favorable. The reader is referred to Plehn, Davis, Williamson, and Duff and Stewart for a more complete description of furunculosis.

  19. Embryonic developmental progression in lake trout (Salvelinus namaycush) (Walbaum, 1792) and its relation to lake temperature

    USGS Publications Warehouse

    Allen, Jeffrey D.; Walker, Glenn K.; Adams, Jean V.; Nichols, S. Jerrine; Edsall, Carol C.

    2005-01-01

    Developmental progression of lake trout (Salvelinus namaycush) embryos was examined with light and scanning electron microscopy. From this examination, key developmental stages were described in detail. The key developmental stages were then applied to individual lake trout egg lots incubated in constant temperatures of 2, 4, 6, 8, and 10°C. We used Belehradek's, Thermodynamic, and Power models, and also developed the Zero model to determine stage specific developmental rates of lake trout eggs for each background temperature. From the models, hatch dates and staging were predicted for temperature regimes from Lake Superior (1990–91) and Lake Huron (1996–97). Based on the existing lake temperature data and the observed spawning dates, the Zero and the Power models predict that post peak spawning may contribute significantly to overall recruitment success for these years.

  20. Hybrid zone structure and the potential role of selection in hybridizing populations of native westslope cutthroat trout (Oncorhynchus clarki lewisi) and introduced rainbow trout (O. mykiss).

    PubMed

    Rubidge, Emily M; Taylor, Eric B

    2004-12-01

    Introgressive hybridization is a common feature of many zones of contact between divergent lineages of fishes. This is particularly common when taxa that are normally allopatric come into artificial (human-induced) secondary contact. We examined 18 native populations of westslope cutthroat trout (Oncorhynchus clarki lewisi, WCT) to determine the extent of introgressive hybridization with introduced rainbow trout (O. mykiss, RBT) and the genetic structure of hybridizing populations in the upper Kootenay River, southeastern British Columbia, Canada. Using four diagnostic nuclear loci we calculated a hybrid index, inbreeding coefficient, FIS, and the linkage disquilibrium correlation coefficient, Rij, for each locality to determine the distribution of genotypes in each population. We also categorized the 142 hybrid individuals found across localities into four hybrid classes based on their genotypes. The majority of localities (11/18) showed a unimodal distribution of genotypes skewed towards genotypes of WCT. Two localities, however (lower Gold Creek and Lodgepole Creek) showed a flat to bimodal distribution and one site (lower Bull River) showed a unimodal distribution skewed towards RBT genotypes. The majority of hybrid individuals were classified genotypically as WCT backcrosses (59%) and post-F1 individuals (24%). We found a skewed ratio of pure WCT to pure RBT (17:1) and only four F1 hybrids (3%), suggesting that the spread of RBT alleles may be facilitated by hybrids straying to neighbouring populations. We also tested for the action of selection in one population using cohort analyses, but found little evidence of differential selection between pure WCT and hybrid individuals. Pooled across age classes there were significant differences in genotypic frequencies among loci suggesting differential introgression. There was no asymmetry to the hybridization between rainbow trout and westslope cutthroat trout because both species' mitochondrial DNA haplotypes were

  1. Factors controlling the abundance of rainbow trout in the Colorado River in Grand Canyon in a reach utilized by endangered humpback chub

    USGS Publications Warehouse

    Korman, Josh; Yard, Michael D.; Yackulic, Charles B.

    2015-01-01

    We estimated the abundance, survival, movement, and recruitment of non-native rainbow trout in the Colorado River in Grand Canyon to determine what controls their abundance near the Little Colorado River (LCR) confluence where endangered humpback chub rear. Over a 3-year period, we tagged more than 70,000 trout and recovered over 8,200 tagged fish. Trout density was highest (10,000-25,000 fish/km) in the reach closest to Glen Canyon Dam where the majority of trout recruitment occurs, and was 30-50-fold lower (200-800 fish/km) in reaches near the LCR confluence ~100 km downstream. The extent of rainbow trout movement was limited with less than 1% of recaptures making movements greater than 20 km. However, due to high trout densities in upstream source areas, this small dispersal rate was sufficient to explain the 3-fold increase in the relatively small population near the LCR. Reducing dispersal rates of trout from upstream sources is the most feasible solution to maintain low densities near the LCR to minimize negative effects of competition and predation on humpback chub.

  2. Weekly bull exchange shortens postpartum anestrus in suckled beef cows.

    PubMed

    Miller, V; Ungerfeld, R

    2008-05-01

    The duration of anestrus in cattle was usually shortened when cows were exposed to bulls. The objective of the present experiment was to determine if weekly bull exchange accelerated the resumption of cyclicity in postpartum suckled beef cows. We tested the hypothesis that exposure of postpartum, anestrous, suckled beef cows (extensively managed) to weekly exchange of bulls, accelerates the resumption of cyclicity, compared to continuous exposure to the same bulls. Ninety-one multiparous suckled Hereford and Hereford x Angus cows, <60d postpartum, were assigned to two homogeneous groups. Beginning on December 1st (late spring), the control group (C, n=45) remained with one pair of bulls throughout the breeding period (7 weeks), whereas in the "exchanged" (E, n=46) group two pairs of bulls were exchanged weekly. Based on weekly ultrasonographic examinations of all cows, none had a CL at the start of the experiment and for 2 weeks after the start of bull exposure. However, the accumulated frequency of cows with a CL was greater in group E than in group C cows on week 4 (P=0.024), as well as on weeks 5-7 (P<0.001) after the start of bull exposure. Furthermore, in group E versus group C, there was a higher pregnancy rate 30d after the end of bull exposure (26 of 46, 56.2% vs. 16 of 45, 35.6%; P=0.045). In conclusion, weekly exchange of two pairs of bulls shortened postpartum anestrus in suckled multiparous cows, compared to continuous exposure to a single pair of bulls.

  3. Thallium toxicosis in a Pit Bull Terrier.

    PubMed

    Volmer, Petra A; Merola, Valentina; Osborne, Tanasa; Bailey, Keith L; Meerdink, Gavin

    2006-01-01

    Thallotoxicosis is described in an adult Pit Bull Terrier. The dog exhibited anorexia, emesis, weakness, conscious proprioceptive deficits, and a hemorrhagic diarrhea before death. A severe, acute necrotizing enterocolitis was evident upon histological examination, as was a multifocal to coalescing pulmonary edema. Liver and kidney thallium concentrations were 18 and 26 ppm, respectively. The source of the thallium was determined to be thallium sulfate obtained by a person with the intent to harm family members. Although thallium has not been produced in the United States for 20 years, this report demonstrates the need to consider thallium toxicosis as a differential diagnosis for animals presenting with vague and mixed gastrointestinal and neurological signs.

  4. MALLEABLE IRON BULL LADLE, HOLDS IRON AFTER IT IS TAPPED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    MALLEABLE IRON BULL LADLE, HOLDS IRON AFTER IT IS TAPPED OUT OF THE CUPOLA UNTIL IT NEEDED BY POURERS ON THE CONVEYOR LINES WHO FILL MOBILE LADLES ATTACHED TO OVERHEAD RAIL SYSTEMS AS THE BULL LADLE TIPS. - Stockham Pipe & Fittings Company, Malleable Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  5. Short communication: Use of young bulls in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The availability of genomic evaluations since 2008 has resulted in many changes to dairy cattle breeding programs. One such change has been the increased contribution of young bulls (0.8 to 3.9 yr old) to those programs. The increased use of young bulls was investigated using pedigree data and b...

  6. Sire conception rate: New national AI bull fertility evaluation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bull fertility evaluations called Estimated Relative Conception Rate (ERCR) were provided to the industry by Dairy Records Management Systems (DRMS) from 1986 to November 2005. In May 2006, AIPL assumed responsibility for evaluation of U.S. bull fertility. As an initial step, AIPL implemented the ER...

  7. Semen and reproductive profiles of genetically identical cloned bulls.

    PubMed

    Tecirlioglu, R Tayfur; Cooney, Melissa A; Korfiatis, Natasha A; Hodgson, Renee; Williamson, Mark; Downie, Shara; Galloway, David B; French, Andrew J

    2006-06-01

    In this comparative study, reproductive parameters and semen characteristics of cloned bulls (n = 3) derived from somatic cell nuclear transfer (SCNT) were compared to their original cell donor Holstein-Friesian (n = 2) bulls from the same enterprise to assess the differences in reproductive potential between a donor bull and its clones. The parameters evaluated included motility of fresh, frozen-thawed and Percoll-treated frozen-thawed spermatozoa, as well as in vitro fertilization (IVF) ability, embryo quality, birth and survival of calves following IVF and embryo transfer with frozen-thawed semen. With fresh semen, spermatozoa from one cloned bull had lower motility than its donor. Cloned bulls had higher velocity parameters in fresh semen, but those effects were not obvious in frozen-thawed or frozen-thawed semen selected with a Percoll gradient. Semen collected from cloned bulls had significantly higher IVF rates compared to donors; however, embryo development per cleaved embryo or quality of blastocysts did not differ between donors and cloned bulls. Pregnancy and live offspring rates from one donor and its cloned bull did not differ between fresh (40%, 16/40 versus 46%, 17/37) and vitrified/thawed (13%, 2/16 versus 25%, 4/16) embryo transfer following IVF. A total of 26 calves were obtained from genotypically identical donor and cloned bulls with no signs of phenotypical abnormalities. These preliminary results suggested that the physiology of surviving postpubertal cloned bulls and quality of collected semen had equivalent reproductive potential to their original cell donor, with no evidence of any deleterious effects in their progeny.

  8. Growth, morphology, and developmental instability of rainbow trout, Yellowstone cutthroat trout, and four hybrid generations

    USGS Publications Warehouse

    Ostberg, C.O.; Duda, J.J.; Graham, J.H.; Zhang, S.; Haywood, K. P.; Miller, B.; Lerud, T.L.

    2011-01-01

    Hybridization of cutthroat trout Oncorhynchus clarkii with nonindigenous rainbow trout O. mykiss contributes to the decline of cutthroat trout subspecies throughout their native range. Introgression by rainbow trout can swamp the gene pools of cutthroat trout populations, especially if there is little selection against hybrids. We used rainbow trout, Yellowstone cutthroat trout O. clarkii bouvieri, and rainbow trout × Yellowstone cutthroat trout F1 hybrids as parents to construct seven different line crosses: F1 hybrids (both reciprocal crosses), F2 hybrids, first-generation backcrosses (both rainbow trout and Yellowstone cutthroat trout), and both parental taxa. We compared growth, morphology, and developmental instability among these seven crosses reared at two different temperatures. Growth was related to the proportion of rainbow trout genome present within the crosses. Meristic traits were influenced by maternal, additive, dominant, overdominant, and (probably) epistatic genetic effects. Developmental stability, however, was not disturbed in F1 hybrids, F2 hybrids, or backcrosses. Backcrosses were morphologically similar to their recurrent parent. The lack of developmental instability in hybrids suggests that there are few genetic incompatibilities preventing introgression. Our findings suggest that hybrids are not equal: that is, growth, development, character traits, and morphology differ depending on the genomic contribution from each parental species as well as the hybrid generation.

  9. A blood chemistry profile for lake trout

    USGS Publications Warehouse

    Edsall, Carol Cotant

    1999-01-01

    A blood chemistry profile for lake trout Salvelinus namaycush was developed by establishing baseline ranges for several clinical chemistry tests (glucose, total protein, amylase, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, creatine kinase, calcium, and magnesium). Measurements were made accurately and rapidly with a Kodak Ektachem DT60 Analyzer and the Ektachem DTSC Module. Blood serum was collected from both laboratory-reared lake trout (1978 and 1986 year-classes) and feral spawning trout from Lake Michigan and then analyzed in the laboratory. No clinically significant differences were found between samples analyzed fresh and those frozen for 1 or 6 weeks. The ranges in chemistry variables for feral lake trout were generally wider than those for laboratory-reared lake trout, and significant differences existed between male and female feral lake trout for several tests. Blood chemistry profiles also varied seasonally on fish sampled repeatedly.

  10. Tissue carboxylesterase activity of rainbow trout

    SciTech Connect

    Barron, M.G.; Charron, K.A.; Stott, W.T.; Duvall, S.E.

    1999-11-01

    The activity of carboxylesterase (CaE), a class of nonspecific serine hydrolases, was evaluated in vitro in tissues and microsomes of rainbow trout and compared to esterase activity in rats, other fish species, and embryo to adult life stages of trout. Trout gill and liver microsomes exhibited substantial CaE activity and limited variation over the range of 2 to 40 C, with a temperature optimum of approximately 22 C. Trout sera and rat liver microsomes exhibited a temperature optimum of approximately 35 to 40 C. The CaE of trout liver (maximum reaction rate [V{sub max}] = 672 nmol/min/mg microsomal protein) was four times less than in rats. Apparent Michaelis constant (K{sub m}) values ranged from 28 (trout liver) to 214 (trout sera) {micro}M. Values of V{sub max}/K{sub m} suggested that in vivo CaE activity of trout liver would be about three times higher than serum, 135 times higher than gill, and three times lower than rat liver. The CaE activity in whole rainbow trout homogenates significantly increased 300% per gram of tissue to 1,200% per milligram of protein between the yolk-sac and juvenile stages. The CaE activity of whole fish homogenates was not significantly different in juvenile rainbow trout, channel catfish, fathead minnows, and bluegill. The results demonstrate that rainbow trout had high esterase activity over a broad range of temperatures, the CaE activity significantly increased between the yolk-sac and juvenile life stages, and that variation between the CaE activity in trout and three other families of freshwater fish was limited. The CaE activity in fish is expected to substantially influence the accumulation and toxicity of pesticides and other esters entering the aquatic environment.

  11. Associations of adiponectin and fertility estimates in Holstein bulls.

    PubMed

    Kasimanickam, Vanmathy R; Kasimanickam, Ramanathan K; Kastelic, John P; Stevenson, Jeffrey S

    2013-03-15

    Adiponectin is a pleiotropic regulator of numerous biological functions, including gonadal steroidogenesis and might play a role in sperm structures and functions. The objectives were to: (1) determine associations among serum concentrations of adiponectin, testosterone, and prolactin, and the sperm DNA fragmentation index; (2) associate sperm adiponectin mRNA abundance with estimates of fertility (sire conception rate); and (3) determine sperm protein expression of adiponectin and its receptor in pre- and postcapacitated sperm from Holstein bulls. In experiment 1, biweekly serum concentrations of adiponectin, prolactin, and testosterone were greater (P < 0.05) for high fertility bulls compared with average and low fertility bulls. Furthermore, sperm DNA fragmentation index was greater (P < 0.05) for low fertility compared with both average and high fertility bulls. In experiment 2, samples of sperm from a single collection from commercial Holstein bulls (N = 34) were used to evaluate relative sperm mRNA expression of adiponectin and its receptors, AdipoR1 and AdipoR2, and protein levels of adiponectin and its receptors, AdipoR1 and AdipoR2, in pre- and postcapacitation sperm. The mRNA abundance of adiponectin and its receptors, AdipoR1 and AdipoR2, were greater for high fertility bulls (>2 to ≤4 sire conception rate) compared with average (≥2 to ≤2) and low (>-2 to ≤-4) fertility bulls. Based on the sperm capacitation assay, average fertility bulls had a greater percentage of acrosome-reacted sperm at 5 hours than high and low fertility bulls, whereas high fertility bulls had a greater percentage of acrosome-reacted sperm than low fertility bulls. After capacitation, levels of adiponectin protein were lower in average fertility bulls, AdipoR1 was lower in all fertility groups, and AdipoR2 was lower in average and high fertility bulls. In conclusion, adiponectin and its receptors had vital roles in sperm structural and functional traits and consequently

  12. An ecological risk assessment of the acute and chronic effects of the herbicide clopyralid to rainbow trout (Oncorhynchus mykiss)

    USGS Publications Warehouse

    Fairchild, J.F.; Allert, A.L.; Feltz, K.P.; Nelson, K.J.; Valle, J.A.

    2009-01-01

    Clopyralid (3,6-dichloro-2-pyridinecarboxylic acid) is a pyridine herbicide frequently used to control invasive, noxious weeds in the northwestern United States. Clopyralid exhibits low acute toxicity to fish, including the rainbow trout (Oncorhynchus mykiss) and the threatened bull trout (Salvelinus confluentus). However, there are no published chronic toxicity data for clopyralid and fish that can be used in ecological risk assessments. We conducted 30-day chronic toxicity studies with juvenile rainbow trout exposed to the acid form of clopyralid. The 30-day maximum acceptable toxicant concentration (MATC) for growth, calculated as the geometric mean of the no observable effect concentration (68 mg/L) and the lowest observable effect concentration (136 mg/L), was 96 mg/L. No mortality was measured at the highest chronic concentration tested (273 mg/L). The acute:chronic ratio, calculated by dividing the previously published 96-h acutely lethal concentration (96-h ALC50; 700 mg/L) by the MATC was 7.3. Toxicity values were compared to a four-tiered exposure assessment profile assuming an application rate of 1.12 kg/ha. The Tier 1 exposure estimation, based on direct overspray of a 2-m deep pond, was 0.055 mg/L. The Tier 2 maximum exposure estimate, based on the Generic Exposure Estimate Concentration model (GEENEC), was 0.057 mg/L. The Tier 3 maximum exposure estimate, based on previously published results of the Groundwater Loading Effects of Agricultural Management Systems model (GLEAMS), was 0.073 mg/L. The Tier 4 exposure estimate, based on published edge-of-field monitoring data, was estimated at 0.008 mg/L. Comparison of toxicity data to estimated environmental concentrations of clopyralid indicates that the safety factor for rainbow trout exposed to clopyralid at labeled use rates exceeds 1000. Therefore, the herbicide presents little to no risk to rainbow trout or other salmonids such as the threatened bull trout. ?? 2009 US Government.

  13. Population genetic structure in Lahontan cutthroat trout

    USGS Publications Warehouse

    Nielsen, Jennifer L.; Sage, George K.

    2002-01-01

    We used 10 microsatellite loci to examine the genetic population structure of cutthroat trout Oncorhynchus clarki within the Lahontan Basin complex. Genetic diversity was analyzed for trout from Nevada, California, and Utah representing three putative subspecies: Lahontan O. c. henshawi, Paiute O. c. seleniris, and Humboldt (an unnamed subspecies) cutthroat trout. We found significant differences in microsatellite diversity among the three putative subspecies found in this area. Analysis of molecular variance partitioned microsatellite variation as 9.8% among subspecies, 27.7% among populations, and 62.5% within populations of Lahontan Basin cutthroat trout. Genetic distance analyses (Cavalli-Sforza-Edwards and F st) supported unique population structure in cutthroat trout from the Humboldt and Pilot Peak drainages. Pairwise F st values for Lahontan cutthroat trout were not significantly correlated with geographic distance between population pairs (r 2 = 0.008; P < 0.0001), suggesting that they are extremely isolated populations with small effective sizes that are vulnerable to extinction. Two extant hatchery strains of Lahontan cutthroat trout showed genetic associations with different geographic source populations. The Pyramid Lake hatchery strain was most closely associated genetically with fish from Summit Lake. The Pilot Peak hatchery strain was associated genetically with Pilot Peak wild trout (Utah) and Macklin Creek trout (California). The phylogeographic diversity depicted in this study supports unique population structure and suggests important evolutionary relationships needed to evaluate transplanted populations and hatchery supplementation within the basin.

  14. Increase in average testis size of Canadian beef bulls.

    PubMed

    García Guerra, Alvaro; Hendrick, Steve; Barth, Albert D

    2013-05-01

    Selection for adequate testis size in beef bulls is an important part of bull breeding soundness evaluation. Scrotal circumference (SC) is highly correlated with paired testis weight and is a practical method for estimating testis weight in the live animal. Most bulls presented for sale in Canada have SC included in the presale information. Scrotal circumference varies by age and breed, and may change over time due to selection for larger testis size. Therefore, it is important to periodically review the mean SC of various cattle breeds to provide valid bull selection criteria. Scrotal circumference data were obtained from bulls sold in western Canada from 2008 to 2011 and in Quebec from 2006 to 2010. Average scrotal circumferences for the most common beef breeds in Canada have increased significantly in the last 25 years. Differences between breeds have remained unchanged and Simmental bulls still have the largest SC at 1 year of age. Data provided here could aid in the establishment of new suggested minimum SC measurements for beef bulls.

  15. Reproductive behaviour in bulls raised under tropical and subtropical conditions.

    PubMed

    Galina, C S; Horn, M M; Molina, R

    2007-06-01

    The present review describes the behavioral characteristics of bulls raised under tropical and subtropical conditions and emphasizes the difficulties associated with adequately monitoring their performance in the field to predict reproductive potential. Most of the information generated for improving our understanding of bull behavior under range conditions has been generated in Bos taurus bulls. The limited information available in Bos indicus indicates that males searching for cows in estrus display different sexual patterns when compared to B. taurus bulls and a poor selection of a sire utilized in range conditions can have an important impact in cattle production. Screening and selecting [cg1] bulls for desirable reproductive traits and high libido is known to improve the reproductive performance of the herd. The reproductive and genetic potential of a bull is influenced by factors such as management, age, nutrition and problems related to the female such as embryonic death and anestrus. However, behavioral characteristics of bulls when detecting and serving cows in estrus is poorly understood.

  16. Effect of Dursban 44 on semen output of Holstein bulls.

    PubMed

    Everett, R W

    1982-09-01

    Dursban 44, an insecticide for lice control, was applied to 185 Holstein bulls 9 to 52 mo of age. These sires were in various stages of progeny testing at an artificial insemination center. Application of this product killed 7 bulls, and the remaining bulls exhibited varying severity of illness with 6 classified as very sick. This study evaluated the effect of this illness on semen production. Semen output on 40,950 ejaculates from 583 Holstein bulls collected from July 1, 1975, through March 31, 1981, was analyzed to establish normal semen production and to estimate the effect of illness caused by Dursban 44 treatment. Ejaculate number, days between collections by previous number of ejaculates, calendar months, years, and ages of bulls affected the semen output characteristics, original volume, sperm concentration, percent motile sperm, total sperm per ejaculate, percent prefreeze discards, percent postthaw sperm motility, and percent postthaw discards. Ejaculate volume, motility, total percent prefreeze discards, and percent postthaw discards were influenced negatively on the 6 very sick bulls. Percent postthaw discards were higher on all bulls treated with Dursban 44 for up to 6 mo post-treatment.

  17. Fertility management of bulls to improve beef cattle productivity.

    PubMed

    Thundathil, Jacob C; Dance, Alysha L; Kastelic, John P

    2016-07-01

    Global demand for animal proteins is increasing, necessitating increased efficiency of global food production. Improving reproductive efficiency of beef cattle, especially bull fertility, is particularly critical, as one bull can breed thousands of females (by artificial insemination). Identifying the genetic basis of male reproductive traits that influence male and female fertility, and using this information for selection, would improve herd fertility. Early-life selection of elite bulls by genomic approaches and feeding them to optimize postpubertal reproductive potential are essential for maximizing profitability. Traditional bull breeding soundness evaluation, or systematic analysis of frozen semen, eliminates bulls or semen samples that are grossly abnormal. However, semen samples classified as satisfactory on the basis of traditional approaches differ in fertility. Advanced sperm function assays developed for assessing compensatory and noncompensatory (submicroscopic) sperm traits can predict such variations in bull fertility. New knowledge on epigenetic modulations of sperm DNA, messenger RNA, and proteins is fundamental to refine and expand sperm function assays. Sexed semen, plus advanced reproductive technologies (e.g., ovum pickup and in vitro production of embryos) can maximize the efficiency of beef cattle production. This review is focused on genetic considerations for bull selection, physiology of reproductive development, breeding soundness evaluation, recent advances in assessing frozen semen, and existing and emerging uses of sexed semen in beef cattle production.

  18. Nutritional composition analysis of meat from human lactoferrin transgenic bulls.

    PubMed

    Zhao, Jie; Xu, Jianxiang; Wang, Jianwu; Li, Ning

    2013-01-01

    Transgenic technology has many potential advantages in food production. However, the transgenic technology process may influence the composition of food products derived from genetically engineered (GE) animals, which may be adverse to human health. Therefore, it is very important to research the compositions of GE animal products. Here, we analyzed the compositions of meat from the offspring of human lactoferrin (hLF) transgenic cows, which can express human lactoferrin proteins in their mammary gland. Six hLF transgenic bulls and three wide-type (WT) bulls, 10 months of age, were slaughtered for meat composition analysis. To determine the comparative health of hLF bulls for meat analysis, hematological analyses, organ/body weight analyses and pathology analyses were conducted. Results of the meat analysis show that there were no significant differences in the hematological parameters, organ/body weight ratios of hLF and WT bulls (P>0.05), and histopathological examination of the main organs of hLF bulls revealed no abnormalities. Nutrient parameters of meat compositions of hLF and WT bulls did not show any significant differences (P>0.05). All of these results suggest that the hLF transgene did not have an impact on the meat nutrient compositions of hLF bulls.

  19. Successional change in the Lake Superior fish community: population trends in ciscoes, rainbow smelt, and lake trout, 1958-2008

    USGS Publications Warehouse

    Gorman, Owen T.

    2012-01-01

    The Lake Superior fish community underwent massive changes in the second half of the 20th century. Those changes are largely reflected in changes in abundance of the adults of principal prey species, the ciscoes (Coregonus spp.), the invasive rainbow smelt (Osmerus mordax), and the principal predator, lake trout (Salvelinus namaycush). To better understand changes in species abundances, a comprehensive series of gillnet and bottom trawl data collected from 1958 to 2008 were examined. In the late 1950s/early 1960s, smelt abundance was at its maximum, wild lake trout was at its minimum, and an abundance of hatchery lake trout was increasing rapidly. The bloater (Coregonus hoyi) was the prevalent cisco in the lake; abundance was more than 300% greater than the next most abundant cisco, shortjaw cisco (C. zenithicus), followed by kiyi (C. kiyi) and lake cisco (C. artedi). By the mid-1960s, abundance of hatchery lake trout was nearing maximum, smelt abundance was beginning to decline, and abundances of all ciscoes declined, but especially that of shortjaw cisco and kiyi. By the late 1970s, recovery of wild lake trout stocks was well underway and abundances of hatchery lake trout and smelt were declining and the ciscoes were reaching their nadir. During 1980–1990, the fish community underwent a dramatic shift in organization and structure. The rapid increase in abundance of wild lake trout, concurrent with a rapid decline in hatchery lake trout, signaled the impending recovery. Rainbow smelt abundance dropped precipitously and within four years, lake cisco and bloater populations rebounded on the heels of a series of strong recruitment events. Kiyi populations showed signs of recovery by 1989, and shortjaw by 2000, though well below historic maximum abundances. High abundance of adult smelt prior to 1980 appears to be the only factor linked to recruitment failure in the ciscoes. Life history traits of the cisco species were examined to better understand their different

  20. Predator-prey relations and competition for food between age-0 lake trout and slimy sculpins in the Apostle Island region of Lake Superior

    USGS Publications Warehouse

    Hudson, Patrick L.; Savino, Jacqueline F.; Bronte, Charles R.

    1995-01-01

    Slimy sculpins (Cottus cognatus) are an important component of the fish community on reefs and adjacent nursery areas of the Great Lakes and overlap spatially with age-0 lake trout (Salvelinus namaycush). Important interactions between these fishes are possible during the lake trout's first year of life, which could include predation on each other's eggs and larvae, and competition for food resources. We investigated the diets of age-0 lake trout and slimy sculpins on a lake trout spawning reef (Gull Island Shoal) and adjacent nursery area (near Michigan Island) in the Apostle Island region of western Lake Superior during June through September from 1988 through 1991. Organisms in stomachs of 511 lake trout and 562 sculpins were identified and counted. Of the 11 major food types found in age-0 lake trout stomachs from both areas, Mysis was the dominant food item (mean volume in stomachs = 68%) and occurred in about 3/4 of the fish analyzed. Copepods, cladocerans, chironomid pupae, fish, and Bythotrephes were also common in the diet (frequency of occurrence > 4%). Diets of lake trout were more diverse on the reef than on the nursery area where Mysis dominated the diet. Slimy sculpins were only found in lake trout greater than 50 mm. Mysis was an important food item of slimy sculpins over the reef but not over the nursery area, where Diporeia was by far the most important taxon. A variety ofben-thic invertebrates (Asellus, chironomids, benthic copepods, and snails) comprised the bulk of the sculpin diet over the reef. Sculpins also ate lake trout eggs in November. Based on cluster analysis, diets were most similar over the reef where both consumed Mysis, calanoid copepods and chironomid pupae. Diets diverged over the nursery areas where sculpins were strictly benthic feeders and lake trout maintained their planktonic diet. In Lake Superior, where lake trout recruitment through natural reproduction has become well established, the coexistence of the two

  1. Patterns of hybridization among cutthroat trout and rainbow trout in northern Rocky Mountain streams.

    PubMed

    McKelvey, Kevin S; Young, Michael K; Wilcox, Taylor M; Bingham, Daniel M; Pilgrim, Kristine L; Schwartz, Michael K

    2016-02-01

    Introgressive hybridization between native and introduced species is a growing conservation concern. For native cutthroat trout and introduced rainbow trout in western North America, this process is thought to lead to the formation of hybrid swarms and the loss of monophyletic evolutionary lineages. Previous studies of this phenomenon, however, indicated that hybrid swarms were rare except when native and introduced forms of cutthroat trout co-occurred. We used a panel of 86 diagnostic, single nucleotide polymorphisms to evaluate the genetic composition of 3865 fish captured in 188 locations on 129 streams distributed across western Montana and northern Idaho. Although introgression was common and only 37% of the sites were occupied solely by parental westslope cutthroat trout, levels of hybridization were generally low. Of the 188 sites sampled, 73% contained ≤5% rainbow trout alleles and 58% had ≤1% rainbow trout alleles. Overall, 72% of specimens were nonadmixed westslope cutthroat trout, and an additional 3.5% were nonadmixed rainbow trout. Samples from seven sites met our criteria for hybrid swarms, that is, an absence of nonadmixed individuals and a random distribution of alleles within the sample; most (6/7) were associated with introgression by Yellowstone cutthroat trout. In streams with multiple sites, upstream locations exhibited less introgression than downstream locations. We conclude that although the widespread introduction of nonnative trout within the historical range of westslope cutthroat trout has increased the incidence of introgression, sites containing nonadmixed populations of this taxon are common and broadly distributed.

  2. Effect of brook trout removal from a spawning stream on an adfluvial population of Lahontan cutthroat trout

    USGS Publications Warehouse

    Scoppettone, G. Gary; Rissler, Peter H.; Shea, Sean P.; Somer, William

    2012-01-01

    Independence Lake (Nevada and Sierra counties, California) harbors the only extant native population of Lahontan cutthroat trout Oncorhynchus clarkii henshawi in the Truckee River system and one of two extant adfluvial populations in the Lahontan basin. The persistence of this population has been precarious for more than 50 years, with spawning runs consisting of only 30–150 fish. It is assumed that this population was much larger prior to the introduction of nonnative brook trout Salvelinus fontinalis. Brook trout overlap with cutthroat trout in upper Independence Creek, where the cutthroat trout spawn and their resulting progeny emigrate to Independence Lake. In 2005, we began removing brook trout from upper Independence Creek using electrofishers and monitored the cutthroat trout population. Stomach analysis of captured brook trout revealed cutthroat trout fry, and cutthroat trout fry survival increased significantly from 4% to 12% with brook trout removal. Prior to brook trout removal, the only Lahontan cutthroat trout progeny emigrating to Independence Lake were fry; with brook trout removal, juveniles were found entering the lake. In 2010, 237 potential spawners passed a prefabricated weir upstream of Independence Lake. Although the results of this study suggest that brook trout removal from upper Independence Creek has had a positive influence on the population dynamics of Independence Lake Lahontan cutthroat trout, additional years of removal are needed to assess the ultimate effect this action will have upon the cutthroat trout population.

  3. Use of an annular chamber for testing thermal preference of westslope cutthroat trout and rainbow trout

    USGS Publications Warehouse

    McMahon, T.E.; Bear, E.A.; Zale, A.V.

    2008-01-01

    Remaining populations of westslope cutthroat trout (Oncorhynchus clarkii lewisi) in western North America are primarily confined to cold headwaters whereas nonnative rainbow trout (Oncorhynchus mykiss) predominate in warmer, lower elevation stream sections historically occupied by westslope cutthroat trout. We tested whether differing thermal preferences could account for the spatial segregation observed in the field. Thermal preferences of age-1 westslope cutthroat trout and rainbow trout (125 to 150 mm total length) were assessed in the laboratory using a modified annular preference chamber at acclimation temperatures of 10, 12, 14, and 16??C Final preferred temperature of westslope cutthroat trout (14.9??C) was similar to that of rainbow trout (14.8??C) when tested in a thermal gradient of 11-17??C The high degree of overlap in thermal preference indicates the two species have similar thermal niches and a high potential for competition. We suggest several modifications to the annular preference chamber to improve performance in future studies.

  4. The cutthroat trout Y chromosome is conserved with that of rainbow trout.

    PubMed

    Alfaqih, M A; Phillips, R B; Wheeler, P A; Thorgaard, G H

    2008-01-01

    Five genetic markers previously shown to be located on the sex chromosomes of rainbow trout (Oncorhynchus mykiss) were tested for linkage with the sex locus of Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri) in a genetic cross created from a rainbow x cutthroat male hybrid. We show that the sex locus of both rainbow and cutthroat trout is on the same homologous linkage group. Fluorescence in situ hybridization (FISH) using a probe for the microsatellite marker Omm1665, which maps close to the sex locus of Yellowstone cutthroat trout, was used to identify the Y chromosome of cutthroat trout in the hybrid. The Y chromosome of cutthroat trout is sub-telocentric and lacks a DAPI band found on the short arm of the Y chromosome of some rainbow trout males.

  5. Sulfonamide toxicity in brook trout

    USGS Publications Warehouse

    Wood, E.M.; Yasutake, W.T.; Snieszko, S.F.

    1954-01-01

    Sterility was observed in female brook trout that were treated with sulfamerazine at frequent intervals for 2 years to control endemic furunculosis. Feeding sulfamerazine for a period of 8 months caused massive kidney damage similar to that observed in humans who develop allergies to “sulfa” drugs. Kidney damage of the type observed would probably cause renal insufficiency which would handicap any physiological function including reproduction. Feeding sulfonamides for periods up to 13 weeks did not produce kidney damage.

  6. Microsatellite diversity and conservation of a relic trout population: McCloud River redband trout

    USGS Publications Warehouse

    Nielsen, J.L.; Crow, K.D.; Fountain, Monique C.

    1999-01-01

    Rainbow trout native to the McCloud River, California, USA (Oncorhynchus mykiss stonei) are thought to represent a relic, nonanadromous trout adapted to harsh, fragmented environments. These fish, commonly named McCloud River ‘redband’ trout, survive in their most primitive form in a small, spring-fed stream, Sheepheaven Creek, in the upper McCloud River drainage. Turn-of-the-century fisheries records document both coastal anadromous steelhead and freshwater resident trout within the McCloud River drainage. The phylogenetic position of the McCloud River redband trout within O. mykiss has been debated for over 50 years. Based on phenotypic evidence, these fish were first reported as ‘southern Sierra golden trout’ by Wales in 1939. Behnke (1970) considered them a relic subspecies of nonanadromous, fine-scaled trout. Allozyme and mitochondrial DNA evidence suggested a coastal lineage. In this study, we examined within- and among-basin genetic associations for Sheepheaven Creek redband trout using 11 microsatellite loci. Within-basin analyses supported unique genetic characteristics in Sheepheaven Creek’s trout in comparisons with other McCloud River rainbow trout. Microsatellite data supported significant independence between Sheepheaven Creek fish and hatchery rainbow trout. Inter-basin genetic distance analyses positioned Sheepheaven Creek fish with samples collected from Lassen Creek, a geographically proximate stream containing inland redband trout. California’s redband trout shared a close genetic association with Little Kern River golden trout (O.m. whitei) and isolated rainbow trout from Rio Santo Domingo, Baja, Mexico (O.m. nelsoni), suggesting a vicariant distribution of microsatellite diversity throughout the southern range of this species.

  7. Adult Recruitment Practices.

    ERIC Educational Resources Information Center

    Kaufman, Juliet, Ed.; And Others

    Findings of an American College Testing Program 1981 survey on college recruitment of adult students are summarized, and 12 articles on adult recruitment are presented. Titles and authors are as follows: "Adult Recruitment Practices: A Report of a National Survey" (Patricia Spratt, Juliet Kaufmann, Lee Noel); "Three Programs for Adults in Shopping…

  8. Recruitment and Training. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on recruitment and training. "College Choice: The State of Marketing and Effective Student Recruitment Strategies" (Fredrick Muyia Nafukho, Michael F. Burnett) reports on a study of the recruitment strategies used by Louisiana State University's admissions office and College of…

  9. Recruitment Guide for Thailand.

    ERIC Educational Resources Information Center

    Yoshihara, Shoko, Comp.

    This book is intended to provide U.S. university recruiters with information on higher education and student recruitment opportunities in Thailand. Section A describes recruitment strategies that are professionally and culturally appropriate to Thailand; contact information concerning related institutions is also included. A subsection called…

  10. Rainbow Trout Innate Immunity against Flavobacterium psychrophilum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavobacterium psychrophilum infection is associated with significant loss of rainbow trout production in the U.S. and other parts of the world. In 2005, a selective breeding program was initiated at the National Center for Cool and Cold Water Aquaculture to improve rainbow trout innate resistance ...

  11. Some problems of private trout hatchery operators

    USGS Publications Warehouse

    Rucker, Robert R.

    1957-01-01

    Disease, nutritional, and environmental problems in commercial production of trout are discussed, including mortality and age of spawners, copepod and gyrodactylid infections, suitable water temperatures, diseases (especially red mouth and back peel) and inspection of fish. It is concluded that experiences with hatchery procedures have varied greatly and often the commercial trout producer must adjust methods to fit his particular needs and conditions.

  12. Glycosidases Interact Selectively With Mannose-6-Phosphate Receptors of Bull Spermatozoa.

    PubMed

    Aguilera, Andrea C; Boschin, Verónica; Carvelli, Lorena; Cavicchia, Juan C; Sosa, Miguel A

    2016-11-01

    Glycosidases may play a role in sperm maturation during epididymal transit. In this work, we describe the interaction of these enzymes with bull spermatozoa. We found that β-galactosidase associated to spermatozoa can be released under low ionic strength conditions, whereas the interaction of N-acetyl-β-D-glucosaminidase and β-glucuronidase with spermatozoa appeared to be stronger. On the other hand, α-mannosidase and α-fucosidase cannot be removed from the gametes. In addition, part of N-acetyl-β-D-glucosaminidase, β-galactosidase, and β-glucuronidase can also be released by mannose-6-phosphate. Taking into account these data, we explored the presence of cation-independent- and cation-dependent-mannose-6-phosphate receptors in the spermatozoa and found that cation-independent mannose-6-phosphate receptor is highly expressed in bull spermatozoa and cation-dependent-mannose-6-phosphate receptor is expressed at a lesser extent. In addition, by immunofluorescence, we observed that cation-independent-mannose-6-phosphate receptor is mostly located at the acrosomal zone, whereas cation-dependent-mannose-6-phosphate receptor presents a different distribution pattern on spermatozoa during the epididymal transit. N-acetyl-β-D-glucosaminidase and β-glucuronidase isolated from epididymal fluid interacted mostly with cation-independent-mannose-6-phosphate receptor, while β-galactosidase was recognized by both receptors. We concluded that glycosidases might play different roles in bull spermatozoa and that mannos-6-phosphate receptors may act as recruiters of some enzymes. J. Cell. Biochem. 117: 2464-2472, 2016. © 2016 Wiley Periodicals, Inc.

  13. 28. UPPER STATION, LOWER FLOOR, BULL WHEEL ROOM, SAFETY BRAKE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. UPPER STATION, LOWER FLOOR, BULL WHEEL ROOM, SAFETY BRAKE ADJUSTING MACHINERY. - Monongahela Incline Plane, Connecting North side of Grandview Avenue at Wyoming Street with West Carson Street near Smithfield Street, Pittsburgh, Allegheny County, PA

  14. Evidence of excretion of Schmallenberg virus in bull semen

    PubMed Central

    2014-01-01

    Schmallenberg virus (SBV) is a novel orthobunyavirus, discovered in Germany in late 2011. It mainly infects cattle, sheep and goats and could lead to congenital infection, causing abortion and fetal abnormalities. SBV is transmitted by biting midges from the Culicoides genus and there is no evidence that natural infection occurs directly between ruminants. Here, we could detect SBV RNA in infected bull semen using qRT-PCR (three bulls out of seven tested positive; 29 positive semen batches out of 136). We also found that highly positive semen batches from SBV infected bulls can provoke an acute infection in IFNAR-/- mice, suggesting the potential presence of infectious virus in the semen of SBV infected bulls. PMID:24708245

  15. POURING IRON FROM BULL LADLE INTO MOBILE LADLES USED TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    POURING IRON FROM BULL LADLE INTO MOBILE LADLES USED TO FILL MOLDS ON CONVEYOR LINES AFTER FERRO-SILICON IS ADDED TO ENHANCE DUCTILITY AND FLUIDITY. - Southern Ductile Casting Company, Casting, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  16. POURING IRON FROM ELECTRIC FURNACE INTO BULL LADLE AFTER MAGNESIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    POURING IRON FROM ELECTRIC FURNACE INTO BULL LADLE AFTER MAGNESIUM HAD BEEN ADDED TO GENERATE DUCTILE IRON WHEN IT COOLS IN THE MOLD. - Southern Ductile Casting Company, Casting, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  17. 26. UPPER STATION, LOWER FLOOR, BULL WHEEL. Monongahela Incline ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. UPPER STATION, LOWER FLOOR, BULL WHEEL. - Monongahela Incline Plane, Connecting North side of Grandview Avenue at Wyoming Street with West Carson Street near Smithfield Street, Pittsburgh, Allegheny County, PA

  18. HENRY STREET SCHOOL, 1300 BLOCK BULL STREET, DETAIL OF NORTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    HENRY STREET SCHOOL, 1300 BLOCK BULL STREET, DETAIL OF NORTH ELEVATION - Savannah Victorian Historic District, Bounded by Gwinnett, East Broad, West Broad Street & Anderson Lane, Savannah, Chatham County, GA

  19. TRAM HOUSE INTERIOR, LOOKING SOUTHEAST. NOTE TRACTION CABLE BULL WHEEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    TRAM HOUSE INTERIOR, LOOKING SOUTHEAST. NOTE TRACTION CABLE BULL WHEEL AND DEPARTING BUCKET "12," STILL ON RAIL AND JUST PRIOR TO ENGAGING TRACTION CABLE. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  20. 13. Bull Wheel Core Showing Name of Manufacturer (National Supply ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Bull Wheel Core Showing Name of Manufacturer (National Supply Co.), Looking Southwest - David Renfrew Oil Rig, East side of Connoquenessing Creek, 0.4 mile North of confluence with Thorn Creek, Renfrew, Butler County, PA

  1. 17. View of disassembled reduction gear parts including bull and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. View of disassembled reduction gear parts including bull and intermediate gears and pedestal bearing. - Hacienda Azucarera La Esperanza, Steam Engine & Mill, 2.65 Mi. N of PR Rt. 2 Bridge over Manati River, Manati, Manati Municipio, PR

  2. 27. UPPER STATION, LOWER FLOOR, BULL WHEEL, BRAKE AIR CYLINDER. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. UPPER STATION, LOWER FLOOR, BULL WHEEL, BRAKE AIR CYLINDER. - Monongahela Incline Plane, Connecting North side of Grandview Avenue at Wyoming Street with West Carson Street near Smithfield Street, Pittsburgh, Allegheny County, PA

  3. Ecological factors affecting Rainbow Smelt recruitment in the main basin of Lake Huron, 1976-2010

    USGS Publications Warehouse

    O'Brien, Timothy P.; Taylor, William W.; Roseman, Edward F.; Madenjian, Charles P.; Riley, Stephen C.

    2014-01-01

    Rainbow Smelt Osmerus mordax are native to northeastern Atlantic and Pacific–Arctic drainages and have been widely introduced throughout North America. In the Great Lakes region, Rainbow Smelt are known predators and competitors of native fish and a primary prey species in pelagic food webs. Despite their widespread distribution, importance as a prey species, and potential to negatively interact with native fish species, there is limited information concerning stock–recruitment relationships for Rainbow Smelt. To better understand recruitment mechanisms, we evaluated potential ecological factors determining recruitment dynamics for Rainbow Smelt in Lake Huron using data from bottom trawl catches. We specifically evaluated influence of stock size, environmental factors (water temperature, lake levels, and precipitation), and salmonine predation on the production of age-0 recruits from 1976 to 2010. Rainbow Smelt recruitment was negatively related to stock size exceeding 10 kg/ha, indicating that compensatory, density-dependent mortality from cannibalism or intraspecific competition was an important factor related to the production of age-0 recruits. Recruitment was positively related to spring precipitation suggesting that the amount of stream-spawning habitat as determined by precipitation was important for the production of strong Rainbow Smelt recruitment. Additionally, density of age-0 Rainbow Smelt was positively related to Lake Trout Salvelinus namaycush abundance. However, spawning stock biomass of Rainbow Smelt, which declined substantially from 1989 to 2010, was negatively associated with Lake Trout catch per effort suggesting predation was an important factor related to the decline of age-2 and older Rainbow Smelt in Lake Huron. As such, we found that recruitment of Rainbow Smelt in Lake Huron was regulated by competition with or cannibalism by older conspecifics, spring precipitation influencing stream spawning habitats, and predation by Lake Trout on

  4. Absence of developmental incompatibility in hybrids between rainbow trout and two subspecies of cutthroat trout.

    PubMed

    Ferguson, M M; Danzmann, R G; Allendorf, F W

    1985-08-01

    We examined the developmental rate of hybrids between rainbow trout (Salmo gairdneri) and two subspecies of cutthroat trout: westslope cutthroat trout (Salmo clarki lewisi) and Yellowstone cutthroat trout (Salmo clarki bouvieri). These taxa show considerable genetic divergence at 42 structural loci encoding enzymes; the mean Nei's D between the rainbow trout and the two species of cutthroat trout is 0.22. We used four measures of developmental rate: time of hatching and yolk resorption, rate of increase in activity of four enzymes, and time of initial detection of seven isozyme loci. The two cutthroat trout subspecies reached hatching and yolk resorption earlier than rainbow trout. Cutthroat trout had higher relative enzyme activities than rainbow trout from deposition of eye pigment to hatching. There was no difference in the rate of increase in enzyme activity or time of initial expression of these loci between these species. Hybrids showed developmental rates intermediate or similar to that of the parental species using all measures. Our results indicate an absence of regulatory and developmental incompatibility between these taxa.

  5. Hybridization dynamics between Colorado's native cutthroat trout and introduced rainbow trout.

    PubMed

    Metcalf, Jessica L; Siegle, Matthew R; Martin, Andrew P

    2008-01-01

    Newly formed hybrid populations provide an opportunity to examine the initial consequences of secondary contact between species and identify genetic patterns that may be important early in the evolution of hybrid inviability. Widespread introductions of rainbow trout (Oncorhynchus mykiss) into watersheds with native cutthroat trout (Oncorhynchus clarkii) have resulted in hybridization. These introductions have contributed to the decline of native cutthroat trout populations. Here, we examine the pattern of hybridization between introduced rainbow trout and 2 populations of cutthroat trout native to Colorado. For this study, we utilized 7 diagnostic, codominant nuclear markers and a diagnostic mitochondrial marker to investigate hybridization in a population of greenback cutthroat trout (Oncorhynchus clarkii stomias) and a population of Colorado River cutthroat trout (Oncorhynchus clarkii pleuriticus). We infer that cutthroat-rainbow trout hybrid swarms have formed in both populations. Although a mixture of hybrid genotypes was present, not all genotype combinations were detected at expected frequencies. We found evidence that mitochondrial DNA introgression in hybrids is asymmetric and more likely from rainbow trout than from cutthroat trout. A difference in spawning time of the 2 species or differences in the fitness between the reciprocal crosses may explain the asymmetry. Additionally, the presence of intraspecific cytonuclear associations found in both populations is concordant with current hypotheses regarding coevolution of mitochondrial and nuclear genomes.

  6. Proliferative kidney disease (PKD) agent Tetracapsuloides bryosalmonae in brown trout populations in Estonia.

    PubMed

    Dash, Megha; Vasemägi, Anti

    2014-05-13

    Proliferative kidney disease (PKD) caused by the myxozoan parasite Tetracapsuloides bryosalmonae is a serious parasitic disease threatening both farmed and wild salmonid populations, but very little is currently known about the distribution of the parasite in the Baltic Sea region. In this study we (1) report the development of a novel multiplex PCR method for fast and reliable screening of T. bryosalmonae; (2) use this multiplex PCR method to show that the PKD agent T. bryosalmonae is widespread in natural brown trout Salmo trutta L. populations in Estonia; (3) evaluate monthly and yearly variation of T. bryosalmonae prevalence in juvenile trout; (4) assess T. bryosalmonae prevalence in different age-classes of fish (0+ vs. 1+ and older) and report the presence of the PKD agent in the kidneys of returning sea trout spawners; and (5) suggest the freshwater bryozoan Plumatella fungosa as a putative invertebrate host of T. bryosalmonae in Estonia. Our results demonstrate a highly heterogeneous distribution of T. bryosalmonae at the micro-geographic scale, indicating that PKD could have an important negative effect on recruitment in Estonian brown trout populations.

  7. Increase in lake trout reproduction in lake huron following the collapse of alewife: Relief from thiamine deficiency or larval predation?

    USGS Publications Warehouse

    Fitzsimons, J.D.; Brown, S.; Brown, L.; Honeyfield, D.; He, J.; Johnson, J.E.

    2010-01-01

    In the Great Lakes there is still uncertainty as to the population level effects of a thiamine deficiency on salmonines caused by high consumption of alewives Alosa pseudoharengus. A resurgence of lake trout Salvelinus namaycush reproduction in Lake Huron following the crash of alewife stocks between 2002 and 2004 provided an opportunity to evaluate the relative effects of this crash on reproduction through relief from either alewife mediated thiamine deficiency or alewife predation on larval lake trout relative to possible changes in the size of the lake trout spawning stock. Changes in mean lake trout egg thiamine concentration post crash at one spawning reef in Parry Sound, wheremean thiamine concentration increased by almost two fold, were consistent with diet switching from alewives to rainbow smelt Osmerus mordax, the next most abundant prey fish in Lake Huron. Although thiamine levels for lake trout collected at a second reef in Parry Sound did not change post-crash, levels both pre- and post-crash were consistent with a rainbow smelt diet. A reef specific fry emergence index was found to be positively related to reef specific egg thiamine concentration but negatively related to reef specific occurrence of EMS, a thiamine deficiency related mortality syndrome. We found little evidence for overlap between the timing of spring shoreward migration of alewives and lake trout emergence, suggesting that relief from alewife predation effects had relatively little effect on the observed increase in lake trout recruitment. Numbers of spawners in the north, north-central, and southern zones of the lake increased from 2000 onwards. Overall the abundance post-2003 was higher than from pre-2004, suggesting that spawner abundance may also have contributed to increased lake trout reproduction. However, predicted numbers of spawners and measured abundance of wild recruits in assessment gear were poorly correlated suggesting that the increase in reproduction was not totally

  8. Demographic changes following mechanical removal of exotic brown trout in an Intermountain West (USA), high-elevation stream

    USGS Publications Warehouse

    Saunders, W. Carl; Budy, Phaedra E.; Thiede, Gary P.

    2015-01-01

    Exotic species present a great threat to native fish conservation; however, eradicating exotics is expensive and often impractical. Mechanical removal can be ineffective for eradication, but nonetheless may increase management effectiveness by identifying portions of a watershed that are strong sources of exotics. We used mechanical removal to understand processes driving exotic brown trout (Salmo trutta) populations in the Logan River, Utah. Our goals were to: (i) evaluate the demographic response of brown trout to mechanical removal, (ii) identify sources of brown trout recruitment at a watershed scale and (iii) evaluate whether mechanical removal can reduce brown trout densities. We removed brown trout from 2 km of the Logan River (4174 fish), and 5.6 km of Right Hand Fork (RHF, 15,245 fish), a low-elevation tributary, using single-pass electrofishing. We compared fish abundance and size distributions prior to, and after 2 years of mechanical removal. In the Logan River, immigration to the removal reach and high natural variability in fish abundances limited the response to mechanical removal. In contrast, mechanical removal in RHF resulted in a strong recruitment pulse, shifting the size distribution towards smaller fish. These results suggest that, before removal, density-dependent mortality or emigration of juvenile fish stabilised adult populations and may have provided a source of juveniles to the main stem. Overall, in sites demonstrating strong density-dependent population regulation, or near sources of exotics, short-term mechanical removal has limited effects on brown trout populations but may help identify factors governing populations and inform large-scale management of exotic species.

  9. An ecological risk assessment of the exposure and effects of 2,4-D acid to rainbow trout (Onchorhyncus mykiss)

    USGS Publications Warehouse

    Fairchild, J.F.; Feltz, K.P.; Allert, A.L.; Sappington, L.C.; Nelson, K.J.; Valle, J.A.

    2009-01-01

    30-day safety factor of 559 (e.g., 76/0.163). Assessment of the exposure and response data presented herein indicates that use of 2,4-D acid for invasive weed control in aquatic and terrestrial habitats poses no substantial risk to growth or survival of rainbow trout or other salmonids, including the threatened bull trout (Salvelinus confluentus). ?? 2009 US Government.

  10. An ecological risk assessment of the exposure and effects of 2,4-D acid to rainbow trout (Onchorhyncus mykiss).

    PubMed

    Fairchild, J F; Feltz, K P; Allert, A L; Sappington, L C; Nelson, K J; Valle, J A

    2009-05-01

    a 30-day safety factor of 559 (e.g., 76/0.163). Assessment of the exposure and response data presented herein indicates that use of 2,4-D acid for invasive weed control in aquatic and terrestrial habitats poses no substantial risk to growth or survival of rainbow trout or other salmonids, including the threatened bull trout (Salvelinus confluentus).

  11. Biomass of coastal cutthroat trout in unlogged and previously clearcut basins in the central Coast Range of Oregon

    USGS Publications Warehouse

    Connolly, P.J.; Hall, J.D.

    1999-01-01

    Populations of coastal cutthroat trout Oncorhynchus clarki clarki were sampled in 16 Oregon headwater streams during 1991–1993. These streams were above upstream migration barriers and distributed among basins that had been logged 20–30 and 40–60 years ago and basins that had not been logged but had burned 125–150 years ago. The objective of our study was to characterize the populations and habitats of age-1 or older cutthroat trout within these three forest management types. Streams within unlogged basins had relatively low levels and a small range of trout biomass (g/m2). Streams in basins logged 40–60 years ago supported low levels but an intermediate range of trout biomass. Streams in basins logged 20–30 years ago supported the widest range of biomass, including the lowest and highest biomasses among all streams sampled. The variable that best explained the variation of trout biomass among all 16 streams was the amount of large woody debris (LWD). All streams were heavily shaded during at least part of the year by mostly closed tree canopies. Deciduous trees were more prominent in canopies over streams in logged basins, while conifers were more prominent in the stream canopies of unlogged basins. Our results suggest that trout production in basins extensively clear-cut 20–60 years ago may generally decrease or remain low over the next 50 or more years because of decreasing loads of remnant LWD, persistent low recruitment potential for new LWD, and persistent heavy shading by conifers. These logged basins are not likely to show an increase in trout biomass over the next 50 years unless reset by favorable natural disturbances or by habitat restoration efforts.

  12. Biomass of coastal cutthroat trout in unlogged and previously clear-cut basins in the central Coast Range of Oregon

    USGS Publications Warehouse

    Connolly, P.J.; Hall, J.D.

    1999-01-01

    Populations of coastal cutthroat trout Oncorhynchus clarki clarki were sampled in 16 Oregon headwater streams during 1991-1993. These streams were above upstream migration barriers and distributed among basins that had been logged 20-30 and 40-60 years ago and basins that had not been logged but had burned 125-150 years ago. The objective of our study was to characterize the populations and habitats of age-1 or older cutthroat trout within these three forest management types. Streams within unlogged basins had relatively low levels and a small range of trout biomass (g/m2). Streams in basins logged 40-60 years ago supported low levels but an intermediate range of trout biomass. Streams in basins logged 20-30 years ago supported the widest range of biomass, including the lowest and highest biomasses among all streams sampled. The variable thai best explained the variation of trout biomass among all 16 streams was the amount of large woody debris (LWD). All streams were heavily shaded during at least part of the year by mostly closed tree canopies. Deciduous trees were more prominent in canopies over streams in logged basins, while conifers were more prominent in the stream canopies of unlogged basins. Our results suggest that trout production in basins extensively clear-cut 20-60 years ago may generally decrease or remain low over the next 50 or more years because of decreasing loads of remnant LWD, persistent low recruitment potential for new LWD, and persistent heavy shading by conifers. These logged basins are not likely to show an increase in trout biomass over the next 50 years unless reset by favorable natural disturbances or by habitat restoration efforts.

  13. Lake trout rehabilitation in Lake Huron

    USGS Publications Warehouse

    Eshenroder, Randy L.; Payne, N. Robert; Johnson, James E.; Bowen, Charles; Ebener, Mark P.

    1995-01-01

    Efforts to restore lake trout (Salvelinus namaycush) in Lake Huron after their collapse in the 1940s were underway in the early 1970s with completion of the first round of lampricide applications in tributary streams and the stocking of several genotypes. We assess results of rehabilitation and establish a historical basis for comparison by quantifying the catch of spawning lake trout from Michigan waters in 1929-1932. Sixty-eight percent of this catch occurred in northern waters (MH-1) and most of the rest (15%) was from remote reefs in the middle of the main basin. Sea lampreys (Petromyzon marinus) increased in the early 1980s in the main basin and depressed spawning populations of lake trout. This increase was especially severe in northern waters and appeared to be associated with untreated populations in the St. Marys River. Excessive commercial fishing stemming from unresolved treaty rights also contributed to loss of spawning fish in northern Michigan waters. Seneca-strain lake trout did not appear to be attacked by sea lampreys until they reached a size > 532 mm. At sizes > 632 mm, Seneca trout were 40-fold more abundant than the Marquette strain in matched-planting experiments. Natural reproduction past the fry stage has occurred in Thunder Bay and South Bay, but prospects for self-sustaining populations of lake trout in the main basin are poor because sea lampreys are too abundant, only one side of the basin is stocked, and stocking is deferred to allow commercial gillnetting in areas where most of the spawning occurred historically. Backcross lake trout, a lake trout x splake (s. Fontinalis x s. Namaycush) hybrid, did not reproduce in Georgian Bay, but this genotype is being replaced with pure-strain lake trout, whose early performance appears promising.

  14. Tritrichomonas foetus: prevalence study in naturally mating bulls in Switzerland.

    PubMed

    Bernasconi, Ch; Bodmer, M; Doherr, M G; Janett, F; Thomann, A; Spycher, C; Iten, C; Hentrich, B; Gottstein, B; Müller, N; Frey, C F

    2014-03-01

    Switzerland is officially free from bovine Tritrichomonas foetus. While bulls used for artificial insemination (AI) are routinely examined for this pathogen, bulls engaged in natural mating, as well as aborted fetuses, are only very sporadically investigated, indicating that the disease awareness for bovine tritrichomoniasis is low. Natural mating in cattle is becoming increasingly popular in Switzerland. Accordingly, a re-introduction/re-occurrence of T. foetus in cattle seems possible either via resurgence from a yet unknown bovine reservoir, or via importation of infected cattle. The low disease awareness for bovine tritrichomoniasis might favor an unnoticed re-establishment of T. foetus in the Swiss cattle population. The aim of our study was thus to search for the parasite, and if found, to assess the prevalence of bovine T. foetus in Switzerland. We included (1) bulls over two years of age used in natural mating and sent to slaughter, (2) bulls used for natural service in herds with or without fertility problems and (3) aborted fetuses. Furthermore, the routinely examined bulls used for AI (4) were included in this study. In total, 1362 preputial samples from bulls and 60 abomasal fluid samples of aborted fetuses were analyzed for the presence of T. foetus by both in vitro cultivation and molecular analyses. The parasite could not be detected in any of the samples, indicating that the maximal prevalence possibly missed was about 0.3% (95% confidence). Interestingly, in preputial samples of three bulls of category 1, apathogenic Tetratrichomonas sp. was identified, documenting a proof-of-principle for the methodology used in this study.

  15. Adult Triploids in a Rainbow Trout Family

    PubMed Central

    Thorgaard, Gary H.; Gall, Graham A. E.

    1979-01-01

    Six triploid individuals were found in a full-sib family of 11 adult rainbow trout (Salmo gairdneri) from a domesticated hatchery stock. The triploid individuals were normal in size and external appearance, had underdeveloped gonads, and showed no evidence of 3n/2n chimerism or mosaicism. XXY triploids were males, suggesting that the Y chromosome is male determining in trout. Because they may avoid production losses associated with sexual maturation in normal fish, triploid trout and salmon could potentially be useful in fish culture. PMID:546676

  16. Diagnostic single nucleotide polymorphisms for identifying westslope cutthroat trout (Oncorhynchus clarki lewisi), Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) and rainbow trout (Oncorhynchus mykiss).

    PubMed

    Kalinowski, S T; Novak, B J; Drinan, D P; Jennings, R deM; Vu, N V

    2011-03-01

    We describe 12 diagnostic single nucleotide polymorphism (SNP) assays for use in species identification among rainbow and cutthroat trout: five of these loci have alleles unique to rainbow trout (Oncorhynchus mykiss), three unique to westslope cutthroat trout (O. clarkii lewisi) and four unique to Yellowstone cutthroat trout (O. clarkii bouvieri). These diagnostic assays were identified using a total of 489 individuals from 26 populations and five fish hatchery strains.

  17. Short communication: Use of young bulls in the United States.

    PubMed

    Hutchison, J L; Cole, J B; Bickhart, D M

    2014-05-01

    The availability of genomic evaluations since 2008 has resulted in many changes to dairy cattle breeding programs. One such change has been the increased contribution of young bulls (0.8 to 3.9 yr old) to those programs. The increased use of young bulls was investigated using pedigree data and breeding records obtained from the US national dairy database (Beltsville, MD). The adoption of genotyping was so rapid that by 2009, >90% of all Holstein artificial insemination (AI) service sires and 86% of Jersey AI service sires were genotyped, regardless of age. The percentage of sons sired by young bulls increased by 49 percentage points (10% in 2008 compared with 59% in 2012) due to the onset of genomic evaluations for Holsteins and by 46 percentage points for Jerseys (11 and 57%, respectively). When limiting these data to sons retained for breeding purposes through AI, the increase was even more dramatic, increasing approximately 80 percentage points from 2008 to 2012 for both Holsteins and Jerseys (1, 5, 28, 52, and 81% for Holsteins and 3, 4, 43, 46, and 82% for Jerseys from 2008 through 2012). From US breeding records from 2007 through 2012, 24,580,793 Holstein and 1,494,095 Jersey breedings were examined. Young bulls accounted for 28% and 25% of Holstein and Jersey breedings in 2007, respectively. These percentages increased to 51% of Holstein and 52% of Jersey breedings in 2012, representing 23- and 27-percentage-unit increases, respectively. Matings to genotyped young bulls have rapidly increased while the use of nongenotyped bulls has diminished since the onset of genomics. Mean sire age for Holstein male progeny born in 2012 was 2.7 yr younger than males born in 2006, and 1.3 yr younger for females; corresponding values for Jerseys were 2.3 and 0.9 yr. Holstein male offspring had an increase of 281 kg between 2006 and 2012, compared with 197 kg between 2000 and 2006 for parent averages (PA) for milk, an increase of 84 kg between the 2 periods. Jersey male

  18. The sequential appearance of sperm abnormalities after scrotal insulation or dexamethasone treatment in bulls.

    PubMed Central

    Barth, A D; Bowman, P A

    1994-01-01

    Scrotal insulation and dexamethasone treatment were used as a model to compare the effect of testicular heating and stress on spermatogenesis. Insulation was applied to the scrotum of eight bulls (insulated) for a period of four days, eight bulls were treated daily for seven days with 20 mg dexamethasone injected intramuscularly, and four bulls were untreated controls. Semen from four bulls in each group was collected and evaluated over a six-week period after treatment. Blood samples for testosterone analysis were taken hourly for eight hours at the beginning and the end of the six-week period from the control bulls and before and after treatment from the four insulated and four dexamethasone-treated bulls that were not used for semen collection. At the end of the last blood sampling period, the four bulls in each group were castrated for the collection of testicular tissue for the determination of testosterone concentrations. Basal, peak episodic, and mean serum testosterone concentrations among control bulls, pre and postinsulated bulls, and pretreatment samples of dexamethasone-treated bulls were not different (p > 0.05); however, bulls that had received dexamethasone treatments had significantly lower basal, peak episodic, and mean testosterone concentrations (p < 0.05). Tissue concentrations of testosterone in control, insulated, and dexamethasone-treated bulls were not significantly different but tended to be lower in dexamethasone-treated bulls (p > 0.13). The spermiograms of the control bulls varied insignificantly over the six-week sampling period; however, there was a marked increase in sperm defects in insulated and dexamethasone-treated bulls. The types of sperm defects and the temporal relationships of rises and declines of sperm defects were quite similar for both treatments. All bulls recovered to approximately pretreatment levels of sperm defects by six weeks after the initiation of treatment. Results indicate that two of the most common types of

  19. The relationship of bull fertility to sperm nuclear shape

    USGS Publications Warehouse

    Ostermeier, G.C.; Sargeant, G.A.; Yandell, B.S.; Parrish, J.J.

    2001-01-01

    group had a linear relationship (r .89, P .05) with fertility. To construct a plot of mean sperm shapes, a novel technique to automatically orient and identify the anterior tip of the sperm head was developed. The mean nuclear shape of high-fertility sperm was more elongated and tapered than those of lower fertility. A discriminant function (P .05) was also constructed that separated the 6 bulls into 2 groups based only on the harmonic amplitudes or sperm nuclear shape. The bulls were correctly classified into the 2 fertility groups. A comparison of sperm chromatin structure analysis (SCSA) and harmonic amplitudes found that overall size variance, anterior roundness, and posterior taperedness of sperm nuclei were related to chromatin stability (P .05). Some of the differences observed in sperm nuclear shape between the high- and lower-fertility bulls may be explained by varying levels of chromatin stability. However, sperm nuclear shape appears to contain additional information from chromatin stability alone. In this particular study, with 6 bulls, all with good chromatin quality, sperm nuclear shape was a better predictor of bull fertility.

  20. Behavioral aspects of electronic bull separation and mate allocation in multiple-sire mating paddocks.

    PubMed

    Lee, C; Prayaga, K C; Fisher, A D; Henshall, J M

    2008-07-01

    Controlling spatial positioning of cattle through use of electronic collars could provide new ways to farm under extensive conditions. This study examined the potential for bulls to be controlled during mating using mild electric shocks delivered through radio-controlled collars. Eighteen Belmont Red bulls were fitted with collars containing the Global Positioning System and that were able to emit a mild electric shock (500 mW) at the top of the neck behind the poll. Eighteen Belmont Red cows were fitted with Global Positioning System collars only. The experiment was replicated 3 times in 3 paddocks. Each paddock contained 2 bulls and 1 cow in induced estrus. On d 1, the bulls were either assigned to the cow or not assigned to the cow, and on d 2, the assignments were reversed, and bulls received the other treatment using a new cow. Treatments were applied for 2 h on each day. The nonassigned bull received a mild electric shock on approach to either the cow or to a bull, whereas the assigned bull received a mild electric shock on approach to the other bull only. The electric shock was applied when the bulls were within approximately 10 m and moving toward the nonallowed animal. The electric shock was terminated when the animal responded by stopping movement toward the nonallowed animal. In the first 10 min, nonassigned bulls spent less time within 5 m of the cow (P = 0.03) than assigned bulls. Assigned bulls spent more time close to the cow during the entire 120 min on d 1 than on d 2 (P = 0.014). On d 1, the assigned bulls moved more toward the cow and the nonassigned bull than they did on d 2 (P = 0.02). Assigned bulls displayed more sexual behaviors than nonassigned bulls (P = 0.004). Nonassigned bulls were sometimes observed not to approach the cow despite a change in its location. This suggests that the bull associated the electric shock with the cow and not with the location in which it received the electric shock. Instances were observed in which the cow

  1. Recruiting Minority Students.

    ERIC Educational Resources Information Center

    Reed, Bobette P.; Dandridge, William L.

    To help improve private schools' recruitment of minority students, this handbook discusses where and how to begin, recruitment strategies, applicant assessment, and the need for in-school support systems for minority students. The authors stress that each school should begin by analyzing its own objectives, attitudes, and admission program.…

  2. Resources for Recruiters.

    ERIC Educational Resources Information Center

    D'Angelo, Diane; And Others

    Recruitment of participants is a long-standing practice for many programs serving children and families, although the way in which it is approached varies greatly. This volume is presented as a practical tool for practitioners to use in systematizing their recruitment efforts. Section 1, "Reaching Diverse Families," contains an interactive…

  3. Broadening the Recruiting Market.

    ERIC Educational Resources Information Center

    Central All-Volunteer Force Task Force, Washington, DC.

    The purpose of the study is to broaden the enlisted recruiting market, especially for high school graduates and describe measures to complete or expedite actions initiated by ASD (M and RA) (Assistant Secretary of Defense Manpower and Reserve Affairs) and the military services and to take additional actions to enhance recruiting. (Author)

  4. Uroperitoneum attributable to ruptured urachus in a yearling bull.

    PubMed

    Baxter, G M; Zamos, D T; Mueller, P O

    1992-02-15

    Ruptured urachus was found to result in uroperitoneum in a yearling Beefmaster bull. The uroperitoneum was initially believed to be attributable to ruptured bladder secondary to urolithiasis; however, catheter decompression of the bladder through an ischiatic urethrotomy did not resolve the uroperitoneum. The persistent urachus was diagnosed and removed through caudal right flank laparotomy with the bull standing. The urachus was attached to the umbilicus, communicated with the lumen of the bladder, and had a mucosal lining. Ruptured urachus is an unusual cause of uroperitoneum, but can cause clinical signs identical to those of ruptured bladder. Persistent urachus is a congenital abnormality in many species, but may be hereditary in Beefmaster cattle. In addition, the bull in this report developed hyperkalemia, which is considered an unusual finding in cattle with uroperitoneum.

  5. Perineal Bull Gore with Urinary Bladder Perforation and Pneumoperitoneum

    PubMed Central

    R, Santhosh; Barad, Arun Kumar; Ghalige, Hemanth Sureshwara; K, Sridartha; Sharma M, Birkumar

    2013-01-01

    Animal related injuries are frequently reported in India and other countries, where bulls are used for sporting events as well as in places where farming and livestock rearing is practised. The presentation is, many times, atypical and misleading as well. They have unique mechanics of injury. The patterns of the injury are reviewed. An intra-peritoneal urinary bladder injury which is caused by a perineal bull gore with a pneumoperitoneum is unusual and it has not been reported in the literature which was reviewed. We are reporting a successfully treated 25 years old male patient from the slopes of the southern district of Manipur, India, who had presented 40 hours after he was injured. The identification and prompt exploration, keeping in mind the mechanics of bull goring, helps the surgeons to adequately deal such atypical injuries, for optimal outcomes. PMID:23814738

  6. Zinc and magnesium in bull and boar spermatozoa.

    PubMed

    Arver, S; Eliasson, R

    1980-11-01

    Mean +/- s.e.m. concentrations (nmol/10(8) cells) of zinc and magnesium in bull spermatozoa were 30.6 +/- 6.6 and 119 +/- 28.8, respectively. Corresponding values for boar spermatozoa were 16.9 +/- 1.98 and 57.1 +/- 4.3. Bull spermatozoa washed twice in a standard buffered salt solution, pH 7.75, lost 72.6% of their zinc and 46.5% of their magnesium. Boar spermatozoa lost 40% of Zn and 18% of Mg, respectively. Addition of albumin (4% final concentration) to the washing solution did not increase the loss of ions from bull spermatozoa but increased the loss of zinc and magnesium from boar spermatozoa to 52% and 41%, respectively.

  7. Does the introduced brook trout ( Salvelinus fontinalis) affect growth of the native brown trout ( Salmo trutta)?

    NASA Astrophysics Data System (ADS)

    Korsu, Kai; Huusko, Ari; Muotka, Timo

    2009-03-01

    Non-native brook trout have become widely established in North European streams. We combined evidence from an artificial-stream experiment and drainage-scale field surveys to examine whether brook trout suppressed the growth of the native brown trout (age 0 to age 2). Our experimental results demonstrated that brown trout were unaffected by the presence of brook trout but that brook trout showed reduced growth in the presence of brown trout. However, the growth reduction only appeared in the experimental setting, indicating that the reduced spatial constraint of the experimental system may have forced the fish to unnaturally intense interactions. Indeed, in the field, no effect of either species on the growth of the putative competitor was detected. These results caution against uncritical acceptance of findings from small-scale experiments because they rarely scale up to more complex field situations. This and earlier work suggest that the establishment of brook trout in North European streams has taken place mainly because of the availability of unoccupied (or underutilized) niche space, rather than as a result of species trait combinations or interspecific competition per se.

  8. Movement and survival of brown trout and rainbow trout in an ozark tailwater river

    USGS Publications Warehouse

    Quinn, J.W.; Kwak, T.J.

    2011-01-01

    We evaluated the movement of adult brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss in relation to a catch-andrelease area in the White River downstream from Beaver Dam, Arkansas. Nine fish of each species were implanted with radio transmitters and monitored from July 1996 to July 1997. The 1.5- km river length of a catch-and-release area (closed to angler harvest) was greater than the total linear range of 72% of the trout (13 of 18 fish), but it did not include two brown trout spawning riffles, suggesting that it effectively protects resident fish within the catch-and-release area except during spawning. The total detected linear range of movement varied from 172 to 3,559 m for brown trout and from 205 to 3,023mfor rainbow trout. The movements of both species appeared to be generally similar to that in unregulated river systems. The annual apparent survival of both trout species was less than 0.40, and exploitation was 44%.Management to protect fish on spawning riffles may be considered if management for wild brown trout becomes a priority. ?? American Fisheries Society 2011.

  9. Contrasting past and current numbers of bears visiting Yellowstone cutthroat trout streams

    USGS Publications Warehouse

    Haroldson, Mark A.; Schwartz, Charles C.; , JUSTIN E. TEISBERG; , Kerry A. Gunther; , JENNIFER K. FORTIN; , CHARLES T. ROBBINS

    2014-01-01

    Spawning cutthroat trout (Oncorhynchus clarkii bouvieri) were historically abundant within tributary streams of Yellowstone Lake within Yellowstone National Park and were a highly digestible source of energy and protein for Yellowstone’s grizzly bears (Ursus arctos) and black bears (U. americanus). The cutthroat trout population has subsequently declined since the introduction of non-native lake trout (Salvelinus namaycush), and in response to effects of drought and whirling disease (Myxobolus cerebralis). The trout population, duration of spawning runs, and indices of bear use of spawning streams had declined in some regions of the lake by 1997–2000. We initiated a 3-year study in 2007 to assess whether numbers of spawning fish, black bears, and grizzly bears within and alongside stream corridors had changed since 1997– 2000. We estimated numbers of grizzly bears and black bears by first compiling encounter histories of individual bears visiting 48 hair-snag sites along 35 historically fished streams.We analyzed DNA encounter histories with Pradel-recruitment and Jolly-Seber (POPAN) capture-mark-recapture models. When compared to 1997–2000, the current number of spawning cutthroat trout per stream and the number of streams with cutthroat trout has decreased. We estimated that 48 (95% CI¼42–56) male and 23 (95% CI¼21–27) female grizzly bears visited the historically fished tributary streams during our study. In any 1- year, 46 to 59 independent grizzly bears (8–10% of estimated Greater Yellowstone Ecosystem population) visited these streams. When compared with estimates from the 1997 to 2000 study and adjusted for equal effort, the number of grizzly bears using the stream corridors decreased by 63%. Additionally, the number of black bears decreased between 64% and 84%. We also document an increased proportion of bears of both species visiting front-country (i.e., near human development) streams. With the recovery of cutthroat trout, we suggest bears

  10. Central effects of trout tachykinins on heart rate variability in trout.

    PubMed

    Lancien, Frédéric; Mimassi, Nagi; Conlon, John Michael; Le Mével, Jean-Claude

    2009-04-01

    Recent studies in trout have shown that tachykinins might be selectively implicated in important neuroregulatory functions related to the central control of ventilation. In teleost fish, cardiorespiratory coupling probably contributes to heart rate variability (HRV), and the hypoventilatory effects observed after central injection of tachykinins suggest that these peptides also may produce changes in HRV. Consequently, the present study was undertaken to compare the central actions of picomolar doses (25-250 pmol) of trout neuropeptide gamma (NPgamma), substance P (SP), and neurokinin A (NKA) on HRV in unanesthetized rainbow trout. Compared to vehicle-injected trout, Poincaré plot analysis of HRV demonstrated that intracerebroventricular injection of NPgamma dose dependently increased HRV. SP evoked a significant elevation of HRV but only at the highest dose (250 pmol). In contrast, NKA was without any effect on HRV. In conclusion, these results suggest that NPgamma may be selectively implicated in the central control of HRV in trout.

  11. Brown Trout removal effects on short-term survival and movement of Myxobolus cerebralis-resistant rainbow trout

    USGS Publications Warehouse

    Fetherman, Eric R.; Winkelman, Dana L.; Bailey, Larissa L.; Schisler, George J.; Davies, K.

    2015-01-01

    Following establishment of Myxobolus cerebralis (the parasite responsible for salmonid whirling disease) in Colorado, populations of Rainbow Trout Oncorhynchus mykissexperienced significant declines, whereas Brown Trout Salmo trutta densities increased in many locations across the state, potentially influencing the success of M. cerebralis-resistant Rainbow Trout reintroductions. We examined the effects of Brown Trout removal on the short-term (3-month) survival and movement of two crosses of reintroduced, M. cerebralis-resistant Rainbow Trout in the Cache la Poudre River, Colorado. Radio frequency identification passive integrated transponder tags and antennas were used to track movements of wild Brown Trout and stocked Rainbow Trout in reaches where Brown Trout had or had not been removed. Multistate mark–recapture models were used to estimate tagged fish apparent survival and movement in these sections 3 months following Brown Trout removal. A cross between the German Rainbow Trout and Colorado River Rainbow Trout strains exhibited similar survival and movement probabilities in the reaches, suggesting that the presence of Brown Trout did not affect its survival or movement. However, a cross between the German Rainbow Trout and Harrison Lake Rainbow Trout exhibited less movement from the reach in which Brown Trout had been removed. Despite this, the overall short-term benefits of the removal were equivocal, suggesting that Brown Trout removal may not be beneficial for the reintroduction of Rainbow Trout. Additionally, the logistical constraints of conducting removals in large river systems are substantial and may not be a viable management option in many rivers.

  12. Interactions between slimy sculpin and trout: Slimy sculpin growth and diet in relation to native and nonnative trout

    USGS Publications Warehouse

    Zimmerman, J.K.H.; Vondracek, B.

    2007-01-01

    To investigate whether introductions of nonnative trout affect growth and diet of nongame fish in small streams, we designed a field experiment to examine interactions between slimy sculpin Cottus cognatus and native brook trout Salvelinus fontinalis or nonnative brown trout Salmo trutta. We hypothesized that brown trout would compete with and reduce growth of slimy sculpin. We expected no change in slimy sculpin growth in treatments with brook trout because the two species co-occur in their native range and thus may have evolved methods to partition resources and decrease competitive interactions. Enclosures (1 m2) were stocked with (1) juvenile brown trout and slimy sculpin, (2) juvenile brook trout and slimy sculpin, or (3) slimy sculpin alone (control). Fish were stocked at three densities to examine intraspecific versus interspecific competition. Replicates of each treatment were placed in riffles in Valley Creek, Minnesota, and six experimental trials were conducted over three summers (2002-2004). Brown trout presence was associated with reduced growth of large slimy sculpin in enclosures, whereas brook trout presence produced no change in slimy sculpin growth; these effects did not depend on fish density. Brown trout or brook trout presence was not associated with shifts in the diets of slimy sculpin, indicating that reduced slimy sculpin growth in the presence of brown trout was not due to prey selection or prey availability changes. Our research suggests that effects on growth of slimy sculpin in Valley Creek differ between introduced brown trout and native brook trout; however, the mechanisms underlying changes in slimy sculpin growth are unclear. Although brook trout and brown trout appear to fill similar ecological roles in small, coldwater streams, brown trout may negatively impact growth of nongame fish. ?? Copyright by the American Fisheries Society 2007.

  13. Feed characteristics alter growth efficiency of cutthroat trout

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The shift in commercial Rainbow Trout Oncorhynchus mykiss diet formulations toward formulations with more plant ingredient inclusion, and specifically increased soy product inclusion, may have negative implications for less domesticated trout species fed these modern diets. Therefore, the objective ...

  14. The influence of temperament, transportation stress, and endotoxin challenge on body composition traits in Brahman bulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was designed to determine the influence of temperament of bulls on ultrasound body composition traits in response to transportation and an endotoxin challenge. Purebred Brahman bulls were selected from a pool of 60 bulls based on temperament scores measured at weaning (n=8 each: calm, int...

  15. 77 FR 60302 - Special Local Regulations; Red Bull Flugtag Miami, Biscayne Bay; Miami, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-03

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulations; Red Bull Flugtag Miami... during the Red Bull Flugtag. The Red Bull Flugtag is scheduled to take place on Saturday, November 3... to the water below. 150 spectator vessels are expected to attend the event. The special...

  16. 78 FR 57061 - Special Local Regulation; Red Bull Flugtag Miami, Biscayne Bay; Miami, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-17

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation; Red Bull Flugtag Miami..., during the Red Bull Flugtag. The Red Bull Flugtag is scheduled to take place on September 21, 2013. The... foot ramp to the water below. Approximately 100 spectator vessels are anticipated to be at the...

  17. 78 FR 40079 - Special Local Regulations; Red Bull Flugtag Miami, Biscayne Bay; Miami, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-03

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulations; Red Bull Flugtag Miami... Park, in Miami, Florida, during the Red Bull Flugtag event. The Red Bull Flugtag is scheduled to take... flying objects from a 30 foot ramp to the water below. The special local regulation is necessary...

  18. Testicular cytology indicates differences in Sertoli cell counts between "good freezer" and "poor freezer" bulls.

    PubMed

    Rajak, Shailendra Kumar; Thippeswamy, Vijetha Bajjalli; Kumaresan, Arumugam; Layek, Siddhartha Shankar; Mohanty, Tushar Kumar; Gaurav, Mukesh Kumar; Chakravarty, Atish Kumar; Datta, Tirtha Kumar; Manimaran, Ayyasamy; Prasad, Shiv

    2016-01-01

    In artificial insemination, poor quality of semen unsuitable for cryopreservation and susceptibility of spermatozoa to cryodamage in crossbred bulls have been a matter of concern. Present study was designed to identify the testicular cytology indices that might be used to predict the semen quality and cryotolerance of spermatozoa in bulls. Based on the ejaculate rejection rate and sperm cryotolerance, bulls (Holstein Friesian X Tharparkar crossbred) were classified into either good (producing good quality semen with spermatozoa having good cryotolerance; n = 4) or poor (producing poor quality semen with spermatozoa having poor cryotolerance; n = 4). Testicular cytology was studied in all the 8 bulls using fine needle aspiration technique. Testicular cytology of good bulls and poor bulls differed significantly. The proportion of Sertoli cells was significantly higher in good bulls (25.3 ± 1.6) compared to poor bulls (11.0 ± 0.8). The Sertoli cell index was 46.1 ± 5.0 in good bulls while it was only 13.8 ± 1.3 in poor bulls. The cut off values, as determined using Receiver Operating Characteristics analysis, indicate that the bulls having testicular cytogram comprising of < 15.5% Sertoli cells, < 24.3 Sertoli cell index and > 4.0 spermatogenic cells to Sertoli cell ratio might be a poor bull in terms of semen quality and cryotolerance of spermatozoa. The proportion of Sertoli cells in the testicular cytology had positive (P < 0.05) relationship with semen quality and cryotolerance of spermatozoa.

  19. Scale-dependent seasonal pool habitat use by sympatric Wild Brook Trout and Brown Trout populations

    USGS Publications Warehouse

    Davis, Lori A.; Wagner, Tyler

    2016-01-01

    Sympatric populations of native Brook Trout Salvelinus fontinalis and naturalized Brown Trout Salmo truttaexist throughout the eastern USA. An understanding of habitat use by sympatric populations is of importance for fisheries management agencies because of the close association between habitat and population dynamics. Moreover, habitat use by stream-dwelling salmonids may be further complicated by several factors, including the potential for fish to display scale-dependent habitat use. Discrete-choice models were used to (1) evaluate fall and early winter daytime habitat use by sympatric Brook Trout and Brown Trout populations based on available residual pool habitat within a stream network and (2) assess the sensitivity of inferred habitat use to changes in the spatial scale of the assumed available habitat. Trout exhibited an overall preference for pool habitats over nonpool habitats; however, the use of pools was nonlinear over time. Brook Trout displayed a greater preference for deep residual pool habitats than for shallow pool and nonpool habitats, whereas Brown Trout selected for all pool habitat categories similarly. Habitat use by both species was found to be scale dependent. At the smallest spatial scale (50 m), habitat use was primarily related to the time of year and fish weight. However, at larger spatial scales (250 and 450 m), habitat use varied over time according to the study stream in which a fish was located. Scale-dependent relationships in seasonal habitat use by Brook Trout and Brown Trout highlight the importance of considering scale when attempting to make inferences about habitat use; fisheries managers may want to consider identifying the appropriate spatial scale when devising actions to restore and protect Brook Trout populations and their habitats.

  20. Lake trout status in the main basin of Lake Huron, 1973-2010

    USGS Publications Warehouse

    He, Ji X.; Ebener, Mark P.; Riley, Stephen C.; Cottrill, Adam; Kowalski, Adam; Koproski, Scott; Mohr, Lloyd; Johnson, James E.

    2012-01-01

    We developed indices of lake trout Salvelinus namaycush status in the main basin of Lake Huron (1973-2010) to understand increases in the relative abundance of wild year-classes during 1995-2010. Sea lamprey Petromyzon marinus wounds per 100 lake trout declined from 23.63 in 2000 to 5.86-10.64 in 2002-2010. The average age-7 lake trout catch per effort per recruitment (CPE/R; fish•305mof gill net-1•million stocked yearlings-1) increased from 0.56 for the 1973-1990 year-classes to 0.92 for the 1991-2001 year-classes. Total CPE (fish/305 m of gill net) declined from 16.4 fish in 1996 to 4.1 fish in 2010, but the percentage of age-5 and younger lake trout steadily decreased from more than 70% before 1996 to less than 10% by 2009. The modal age in gill-net catches increased from age 5 before 1996 to age 7 by 2005. The average adult CPE increased from 2.8 fish/305 m of gill net during 1978-1995 to 5.34 fish/305 m of gill net during 1996-2010. The 1995-2010 year-classes of wild fish weremore abundant than previous year-classes and were associated with the relatively high adult abundance during 1996-2010. Until the 2002 year-class, there was no decline in age-7 CPE/R; until 2008, there was no decline in adult CPE. Low survival of the 2002 and 2003 year-classes of stocked fish was related to the event of alewife Alosa pseudoharengus population collapse in 2003-2004. Lake trout in the main basin of Lake Huron are undergoing a transition from a hatchery stock to a wild stock, accompanied by an increased uncertainty in delayed recruitment. Future management should pay more attention to the protection of wild recruitment and the abundance of the spawning stock.

  1. Recruitment in Radiotherapy

    ERIC Educational Resources Information Center

    Deeley, T. J.; And Others

    1976-01-01

    The Faculty Board of Radiotherapy and Oncology of the Royal College of Radiobiologists surveyed the factors thought to influence recruitment into the specialty. Possible factors listed in replies of 36 questionnaires are offered. (LBH)

  2. Evaluation of dietary soy sensitivity in snake river cutthroat trout

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hatchery-cultured cutthroat trout fed some commercially available rainbow trout feeds display slow growth and increased mortality. Feed characteristics such as buoyancy and texture alter feed acceptance in some fish species but their effects have not been adequately addressed in cutthroat trout. Th...

  3. Training Tribal Lay Advocates at Sitting Bull College

    ERIC Educational Resources Information Center

    Shelley, W. L.

    2015-01-01

    Students in Sitting Bull College's lay advocate program develop a well-rounded understanding of the law, enabling them to represent defendants in tribal courts. The program offers legal training for its students--and illustrates how American Indian nations can broaden legal representation for Native defendants in tribal courts. It is one of only…

  4. The Case for Bull Dogs and Mother Hens.

    ERIC Educational Resources Information Center

    Neugebauer, Bonnie; Neugebauer, Roger

    1996-01-01

    Describes traits of effective child care team members: instigator--develops ideas; day-dream believer--suggests solutions; jester--relieves tension; mother hen--ensures fair treatment; nervous Nellie--critiques ideas; keeper of the faith--focuses on center's mission; bull dog--keeps on task; compromiser--preserves unity; and mover and…

  5. Exploring Essential Conditions: A Commentary on Bull et al. (2008)

    ERIC Educational Resources Information Center

    Borthwick, Arlene; Hansen, Randall; Gray, Lucy; Ziemann, Irina

    2008-01-01

    The editorial by Bull et al. (2008) on connections between informal and formal learning made explicit one element of solving what Koehler and Mishra (2008) termed a "wicked problem." This wicked (complex, ill-structured) problem involves working with teachers for effective integration of technology in support of student learning. The…

  6. Bulls, Goats, and Pedagogy: Engaging Students in Overseas Development Aid

    ERIC Educational Resources Information Center

    Miles, William F. S.

    2009-01-01

    This article illustrates the profound learning that occurs--for students and instructor alike--when a class on third-world development attempts to undertake foreign aid. With undergraduate, graduate, and departmental money, I purchased bulls and carts for farmers, and goats for widows, in two West African villages. Such experiential learning…

  7. TRAM HOUSE INTERIOR, LOOKING SOUTH. NOTE HORIZONTAL, IDLER, BULL WHEEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    TRAM HOUSE INTERIOR, LOOKING SOUTH. NOTE HORIZONTAL, IDLER, BULL WHEEL TO REVERSE DIRECTION OF TRACTION CABLE. TRAM CABLE DRIVE MOTOR (NO LONGER EXTANT) WAS AT MINE END OF TRAM. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  8. Cultural Connections: Bowl with Frieze of Lions Attacking Bulls

    ERIC Educational Resources Information Center

    School Arts: The Art Education Magazine for Teachers, 2004

    2004-01-01

    This article gives a brief description of the piece of art titled "Bowl with Frieze of Lions Attacking Bulls" which is thought to be the product of a court or palace of the Neo-Assyrian period and dates to the late seventh to eighth century BC, between the reigns of Sargon and Ashurbanipal. The article highlights the piece's most notable…

  9. Relationships among temperament, behavior, and growth during performance testing of bulls.

    PubMed

    Lockwood, S A; Kattesh, H G; Krawczel, P D; Kirkpatrick, F D; Saxton, A M; Rhinehart, J D; Wilkerson, J B

    2015-12-01

    Excitable cattle are dangerous to personnel and have reduced individual performance. The aim of this study was to 1) identify objective criteria for evaluating bull temperament and 2) examine relationships among temperament, behavior, and performance of bulls during an 84-d performance test. Angus bulls ( = 60) were reared in 6 pens based on BW and age. Pen scores (PS; 1 = docile and 5 = very aggressive) were assigned on d -1, 27, 55, and 83. Exit velocity (EV), BW, time to exit the chute, and order through the chute were recorded on d 0, 28, 56, and 84. The ADG was calculated for the 84-d test period, and ultrasound data and frame score calculations were recorded on d 84. Dataloggers measured steps taken, lying time, number of lying bouts, and lying bout duration of bulls ( = 27; 3 pens) from d 3 to 28 and d 59 to 84. Bulls with a d -1 PS of 1 or 2 were categorized as calm (PScalm; = 40), whereas bulls with a PS of 3 or 4 were categorized as excitable (PSexcitable; = 20). Bulls were separated into 2 groups based on the bottom 20 EV (EVcalm) and top 20 EV (EVexcitable) on d 0. Mixed model ANOVA (SAS 9.3) was used to compare groups for the two temperament assessment methods, behavior, and growth performance. Mean EV decreased ( < 0.05) by d 84. Total lying time from d 3 to 28 was greater ( < 0.05) for PScalm bulls when compared with PSexcitable bulls. However, total lying time from d 59 to 84 was greater ( < 0.05) for EVexcitable bulls when compared with EVcalm bulls. Regardless of initial contemporary group assignment, all bulls exited the chute slower ( < 0.001) on d 84 than on d 0. The PSexcitable bulls had greater ( < 0.01) frame scores and greater ADG than PScalm bulls. The PSexcitable bulls had more ( < 0.01) backfat than PScalm bulls. However, ribeye area was smaller ( < 0.01) in EVexcitable bulls than EVcalm bulls. Based on these results, bulls appeared to have habituated over the testing period. Additionally, the potential lack of innate temperament

  10. Snorkeling as an alternative to depletion electrofishing for assessing cutthroat trout and brown trout in stream pools

    USGS Publications Warehouse

    Joyce, M.P.; Hubert, W.A.

    2003-01-01

    We compared abundance and length structure estimates of cutthroat trout (Oncorhynchus clarki) and brown trout (Salmo trutta) of 15 cm total length or greater obtained by snorkeling in stream pools with estimates obtained by depletion electrofishing. We sampled 12 pools in each of two streams formed by large springs in the Salt River Valley of western Wyoming. Snorkeling counts provided a relatively accurate index of depletion electrofishing estimates of abundance of cutthroat trout, but not brown trout. Linear regression analysis showed that snorkeling counts were significantly related to depletion electrofishing estimates for both cutthroat trout (P < 0.001) and brown trout (P = 0.002), but the coefficient of determination for brown trout (r2 = 0.33) was low compared to cutthroat trout (r2 = 0.95). Frequencies of fish in three length classes observed by snorkeling and depletion electrofishing were close to being significantly different for cutthroat trout (P = 0.066) and substantially different for brown trout (P = 0.005). Snorkeling frequently failed to observe fish in the shortest length class (15-29 cm total length) of both cutthroat trout and brown trout.

  11. Diel resource partitioning among juvenile Atlantic Salmon, Brown Trout, and Rainbow Trout during summer

    USGS Publications Warehouse

    Johnson, James H.; McKenna, James E.

    2015-01-01

    Interspecific partitioning of food and habitat resources has been widely studied in stream salmonids. Most studies have examined resource partitioning between two native species or between a native species and one that has been introduced. In this study we examine the diel feeding ecology and habitat use of three species of juvenile salmonids (i.e., Atlantic Salmon Salmo salar, Brown Trout Salmo trutta, and Rainbow Trout Oncorhynchus mykiss) in a tributary of Skaneateles Lake, New York. Subyearling Brown Trout and Rainbow Trout fed more heavily from the drift than the benthos, whereas subyearling Atlantic Salmon fed more from the benthos than either species of trout. Feeding activity of Atlantic Salmon and Rainbow Trout was similar, with both species increasing feeding at dusk, whereas Brown Trout had no discernable feeding peak or trough. Habitat availability was important in determining site-specific habitat use by juvenile salmonids. Habitat selection was greater during the day than at night. The intrastream, diel, intraspecific, and interspecific variation we observed in salmonid habitat use in Grout Brook illustrates the difficulty of acquiring habitat use information for widespread management applications.

  12. Diel resource partitioning among juvenile Atlantic Salmon, Brown Trout, and Rainbow Trout during summer

    USGS Publications Warehouse

    Johnson, James H.; McKenna, James E.

    2015-01-01

    Interspecific partitioning of food and habitat resources has been widely studied in stream salmonids. Most studies have examined resource partitioning between two native species or between a native species and one that has been introduced. In this study we examine the diel feeding ecology and habitat use of three species of juvenile salmonids (i.e., Atlantic Salmon Salmo salar, Brown Trout Salmo trutta, and Rainbow Trout Oncorhynchus mykiss) in a tributary of Skaneateles Lake, New York. Subyearling Brown Trout and Rainbow Trout fed more heavily from the drift than the benthos, whereas subyearling Atlantic Salmon fed more from the benthos than either species of trout. Feeding activity of Atlantic Salmon and Rainbow Trout was similar, with both species increasing feeding at dusk, whereas Brown Trout had no discernable feeding peak or trough. Habitat availability was important in determining site-specific habitat use by juvenile salmonids. Habitat selection was greater during the day than at night. The intrastream, diel, intraspecific, and interspecific variation we observed in salmonid habitat use in Grout Brook illustrates the difficulty of acquiring habitat use information for widespread management applications.

  13. Modelling competition and hybridization between native cutthroat trout and nonnative rainbow and hybrid trout.

    PubMed

    Van Kirk, Robert W; Battle, Laurie; Schrader, William C

    2010-03-01

    Native salmonid fish have been displaced worldwide by nonnatives through hybridization, competition, and predation, but the dynamics of these factors are poorly understood. We apply stochastic Lotka-Volterra models to the displacement of cutthroat trout by rainbow/hybrid trout in the Snake River, Idaho, USA. Cutthroat trout are susceptible to hybridization in the river but are reproductively isolated in tributaries via removal of migratory rainbow/hybrid spawners at weirs. Based on information-theoretic analysis, population data provide evidence that hybridization was the primary mechanism for cutthroat trout displacement in the first 17 years of the invasion. However, under some parameter values, the data provide evidence for a model in which interaction occurs among fish from both river and tributary subpopulations. This situation is likely to occur when tributary-spawned cutthroat trout out-migrate to the river as fry. The resulting competition with rainbow/hybrid trout can result in the extinction of cutthroat trout even when reproductive segregation is maintained.

  14. Brown trout and food web interactions in a Minnesota stream

    USGS Publications Warehouse

    Zimmerman, J.K.H.; Vondracek, B.

    2007-01-01

    1. We examined indirect, community-level interactions in a stream that contained non-native brown trout (Salmo trutta Linnaeus), native brook trout (Salvelinus fontinalis Mitchill) and native slimy sculpin (Cottus cognatus Richardson). Our objectives were to examine benthic invertebrate composition and prey selection of fishes (measured by total invertebrate dry mass, dry mass of individual invertebrate taxa and relative proportion of invertebrate taxa in the benthos and diet) among treatments (no fish, juvenile brook trout alone, juvenile brown trout alone, sculpin with brook trout and sculpin with brown trout). 2. We assigned treatments to 1 m2 enclosures/exclosures placed in riffles in Valley Creek, Minnesota, and conducted six experimental trials. We used three designs of fish densities (addition of trout to a constant number of sculpin with unequal numbers of trout and sculpin; addition of trout to a constant number of sculpin with equal numbers of trout and sculpin; and replacement of half the sculpin with an equal number of trout) to investigate the relative strength of interspecific versus intraspecific interactions. 3. Presence of fish (all three species, alone or in combined-species treatments) was not associated with changes in total dry mass of benthic invertebrates or shifts in relative abundance of benthic invertebrate taxa, regardless of fish density design. 4. Brook trout and sculpin diets did not change when each species was alone compared with treatments of both species together. Likewise, we did not find evidence for shifts in brown trout or sculpin diets when each species was alone or together. 5. We suggest that native brook trout and non-native brown trout fill similar niches in Valley Creek. We did not find evidence that either species had an effect on stream communities, potentially due to high invertebrate productivity in Valley Creek. ?? 2007 Blackwell Publishing Ltd.

  15. Innocent until proven guilty? Stable coexistence of alien rainbow trout and native marble trout in a Slovenian stream.

    PubMed

    Vincenzi, Simone; Crivelli, Alain J; Jesensek, Dusan; Rossi, Gianluigi; De Leo, Giulio A

    2011-01-01

    To understand the consequences of the invasion of the nonnative rainbow trout Oncorhynchus mykiss on the native marble trout Salmo marmoratus, we compared two distinct headwater sectors where marble trout occur in allopatry (MTa) or sympatry (MTs) with rainbow trout (RTs) in the Idrijca River (Slovenia). Using data from field surveys from 2002 to 2009, with biannual (June and September) sampling and tagging from June 2004 onwards, we analyzed body growth and survival probabilities of marble trout in each stream sector. Density of age-0 in September over the study period was greater for MTs than MTa and very similar between MTs and RTs, while density of trout ≥age-1 was similar for MTa and MTs and greater than density of RTs. Monthly apparent survival probabilities were slightly higher in MTa than in MTs, while RTs showed a lower survival than MTs. Mean weight of marble and rainbow trout aged 0+ in September was negatively related to cohort density for both marble and rainbow trout, but the relationship was not significantly different between MTs and MTa. No clear depression of body growth of sympatric marble trout between sampling intervals was observed. Despite a later emergence, mean weight of RTs cohorts at age 0+ in September was significantly higher than weight of both MTs and MTa. The establishment of a self-sustaining population of rainbow trout does not have a significant impact on body growth and survival probabilities of sympatric marble trout. The numerical dominance of rainbow trout in streams at lower altitudes seem to suggest that while the low summer flow pattern of Slovenian streams is favorable for rainbow trout invasion, the adaptation of marble trout to headwater environments may limit the invasion success of rainbow trout in headwaters.

  16. Fate of Tetracapsuloides bryosalmonae (Myxozoa) after infection of brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss.

    PubMed

    Kumar, Gokhlesh; Abd-Elfattah, Ahmed; Saleh, Mona; El-Matbouli, Mansour

    2013-11-25

    Tetracapsuloides bryosalmonae (Myxozoa) is the causative agent of proliferative kidney disease in salmonids. We assessed differences in intensity of T. bryosalmonae infection between brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss from the clinical phase of infection onwards. Specific pathogen-free fish were exposed to T. bryosalmonae spores under controlled laboratory conditions and sampled at 6, 8, 10, 12, 14, and 17 wk post exposure (wpe), and the transmission of T. bryosalmonae from infected fish to the bryozoan Fredericella sultana was observed. Parasite load was determined in fish kidneys by quantitative real-time PCR (qRT-PCR), and parasite stages were detected in kidney, liver, and spleen tissues at different time points by immunohistochemistry. T. bryosalmonae was successfully transmitted from infected brown trout to F. sultana colonies but not from infected rainbow trout. Body length and weight of infected brown trout did not differ significantly from control brown trout during all time points, while length and weight of infected rainbow trout differed significantly compared to controls from 10 to 17 wpe. qRT-PCR revealed that parasite load was significantly higher in kidneys of brown trout compared with rainbow trout. Immunohistochemistry showed high numbers of intra-luminal stages (sporogonic stages) in kidneys of brown trout with low numbers of pre-sporogonic stages. Sporogonic stages were not seen in kidneys of rainbow trout; only high numbers of pre-sporogonic stages were detected. Numbers of pre-sporogonic stages were low in the spleen and liver of brown trout but high in rainbow trout. These data confirmed that there are differences in the development and infection progress of T. bryosalmonae between brown trout and rainbow trout.

  17. Innocent until proven guilty? Stable coexistence of alien rainbow trout and native marble trout in a Slovenian stream

    NASA Astrophysics Data System (ADS)

    Vincenzi, Simone; Crivelli, Alain J.; Jesensek, Dusan; Rossi, Gianluigi; de Leo, Giulio A.

    2011-01-01

    To understand the consequences of the invasion of the nonnative rainbow trout Oncorhynchus mykiss on the native marble trout Salmo marmoratus, we compared two distinct headwater sectors where marble trout occur in allopatry (MTa) or sympatry (MTs) with rainbow trout (RTs) in the Idrijca River (Slovenia). Using data from field surveys from 2002 to 2009, with biannual (June and September) sampling and tagging from June 2004 onwards, we analyzed body growth and survival probabilities of marble trout in each stream sector. Density of age-0 in September over the study period was greater for MTs than MTa and very similar between MTs and RTs, while density of trout ≥age-1 was similar for MTa and MTs and greater than density of RTs. Monthly apparent survival probabilities were slightly higher in MTa than in MTs, while RTs showed a lower survival than MTs. Mean weight of marble and rainbow trout aged 0+ in September was negatively related to cohort density for both marble and rainbow trout, but the relationship was not significantly different between MTs and MTa. No clear depression of body growth of sympatric marble trout between sampling intervals was observed. Despite a later emergence, mean weight of RTs cohorts at age 0+ in September was significantly higher than weight of both MTs and MTa. The establishment of a self-sustaining population of rainbow trout does not have a significant impact on body growth and survival probabilities of sympatric marble trout. The numerical dominance of rainbow trout in streams at lower altitudes seem to suggest that while the low summer flow pattern of Slovenian streams is favorable for rainbow trout invasion, the adaptation of marble trout to headwater environments may limit the invasion success of rainbow trout in headwaters.

  18. Evidence of offshore lake trout reproduction in Lake Huron

    USGS Publications Warehouse

    DeSorcie, Timothy J.; Bowen, Charles A.

    2003-01-01

    Six Fathom Bank-Yankee Reef, an offshore reef complex, was an historically important spawning area believed to represent some of the best habitat for the rehabilitation of lake trout Salvelinus namaycush in Lake Huron. Since 1986, lake trout have been stocked on these offshore reefs to reestablish self-sustaining populations. We sampled with beam trawls to determine the abundance of naturally reproduced age-0 lake trout on these offshore reefs during May-July in 1994-1998 and 2000-2002. In total, 123 naturally reproduced lake trout fry were caught at Six Fathom Bank, and 2 naturally reproduced lake trout fry were caught at nearby Yankee Reef. Our findings suggest that this region of Lake Huron contains suitable habitat for lake trout spawning and offers hope that lake trout rehabilitation can be achieved in the main basin of Lake Huron.

  19. Relationships between Boron concentrations and trout in the firehole river, Wyoming: Historical information and preliminary results of a field study

    USGS Publications Warehouse

    Meyer, J.S.; Boelter, A.M.; Woodward, D.F.; Goldstein, J.N.; Farag, A.M.; Hubert, W.A.

    1998-01-01

    The Firehole River (FHR) in Yellowstone National Park (YNP) is a world- renowned recreational fishery that predominantly includes rainbow trout (RBT, Oncorhynchus mykiss) and brown trout (BNT, Salmo trutta). The trout populations apparently are closed to immigration and have been self- sustaining since 1955. Inputs from hot springs and geysers increase the temperature and mineral content of the water, including elevating the boron (B) concentrations to a maximum of ~1 mg B/L. Both RBT and BNT reside in warm-water reaches, except when the water is extremely warm (???~25??C) during midsummer. They spawn in late fall and early winter, with documented spawning of BNT in the cold-water reach upstream from the Upper Geyser Basin and of RBT in the Lower Geyser Basin reach, where water temperatures presumably are the warmest; however, successful recruitment of RBT in waters containing ~1 mg B/L has not been demonstrated conclusively. Thus, we began investigating the relationships among temperature, B concentrations, other water-quality parameters, and the distribution and reproduction of trout in the FHR in spring 1997. However, atypical high water flows and concomitant lower than historical temperatures and B concentrations during summer 1997 preclude conclusions about avoidance of high B concentrations.

  20. Declining survival of lake trout stocked during 1963-1986 in U.S. waters of Lake Superior

    USGS Publications Warehouse

    Hansen, Michael J.; Ebener, Mark P.; Schorfhaar, Richard G.; Schram, Stephen T.; Schreiner, Donald R.; Selgeby, James H.

    1994-01-01

    The average catch per effort (CPE) values for the 1963–1982 year-classes of stocked lake trout Salvelinus namaycush caught at age 7 in gill nets and for the 1976–1986 year-classes caught at ages 2–4 in trawls declined significantly in U.S. waters of Lake Superior. The declines in CPE were not explained by reduced stocking, but rather by significant declines in survival indices of the year-classes of stocked lake trout. Increases in mortality occurred in year-classes before the fish reached ages 2–4, before they were recruited into the sport and commercial fisheries, and before they reached sizes vulnerable to sea lamprey predation. We conclude that declining abundance of stocked lake trout resulted from increased mortality, which may have been caused by competition, predation, or by a combination of these and other factors. Restoration of lake trout in Lake Superior may now depend on prudent management of naturally reproducing stocks rather than on stocking of hatchery-reared fish.

  1. Relationships between boron concentrations and trout in the Firehole River, Wyoming: historical information and preliminary results of a field study.

    PubMed

    Meyer, J S; Boelter, A M; Woodward, D F; Goldstein, J N; Farag, A M; Hubert, W A

    1998-01-01

    The Firehole River (FHR) in Yellowstone National Park (YNP) is a world-renowned recreational fishery that predominantly includes rainbow trout (RBT, Oncorhynchus mykiss) and brown trout (BNT, Salmo trutta). The trout populations apparently are closed to immigration and have been self-sustaining since 1955. Inputs from hot springs and geysers increase the temperature and mineral content of the water, including elevating the boron (B) concentrations to a maximum of approximately 1 mg B/L. Both RBT and BNT reside in warm-water reaches, except when the water is extremely warm (> or = approximately 25 degrees C) during midsummer. They spawn in late fall and early winter, with documented spawning of BNT in the cold-water reach upstream from the Upper Geyser Basin and of RBT in the Lower Geyser Basin reach, where water temperatures presumably are the warmest; however, successful recruitment of RBT in waters containing approximately 1 mg B/L has not been demonstrated conclusively. Thus, we began investigating the relationships among temperature, B concentrations, other water-quality parameters, and the distribution and reproduction of trout in the FHR in spring 1997. However, atypical high water flows and concomitant lower than historical temperatures and B concentrations during summer 1997 preclude conclusions about avoidance of high B concentrations.

  2. Biotic and abiotic factors related to lake herring recruitment in the Wisconsin waters of Lake Superior, 1984-1998

    USGS Publications Warehouse

    Hoff, Michael H.

    2004-01-01

    Lake Superior lake herring (Coregonus artedi) recruitment to 13-14 months of age in the Wisconsin waters of Lake Superior varied by a factor of 5,233 during 1984-1998. Management agencies have sought models that accurately predict recruitment, but no satisfactory model had previously been developed. Lake herring recruitment was modeled to determine which factors most explained recruitment variability. The Ricker stock-recruitment model derived from only the paired stock and recruit data explained 35% of the variability in the recruitment data. The functional relationship that explained the greatest amount of recruitment variation (93%) included lake herring stock size, lake trout (Salvelinus namaycush) population size, slimy sculpin (Cottus cognatus) biomass, the interaction of mean daily wind speed in April (month of hatch) and lake herring stock size, and mean air temperature in April (when lake herring are 12-months old). Model results were interpreted to mean that lake herring recruitment was affected negatively by: slimy sculpin predation on lake herring ova; predation on age-0 lake herring by lake trout; and adult cannibalism on lake herring larvae, which was reduced by increased wind speed. April temperature was the variable that explained the least amount of variability in recruitment, but lake herring recruitment was positively affected by a warm April, which shortened winter and apparently reduced first-winter mortality. Stock size caused compensatory, density-dependent mortality on lake herring recruits. Management efforts appear best targeted at stock size protection, and empirical data implies that stock size in the Wisconsin waters of the lake should be maintained at 2.1-15.0 adults/ha in spring, bottom-trawl surveys.

  3. Microsatellite analyses of the trout of northwest Mexico

    USGS Publications Warehouse

    Nielsen, J.L.; Sage, G.K.

    2001-01-01

    The trout of northwest Mexico represent an undescribed group of fish considered part of the Oncorhynchus mykiss (Pacific trout) complex of species and subspecies. Recent genetic studies have shown these fish to have important genetic diversity and a unique evolutionary history when compared to coastal rainbow trout. Increased levels of allelic diversity have been found in this species at the southern extent of its range. In this study we describe the trout in the Sierra Madre Occidental from the rios Yaqui, Mayo, Casas Grandes and de Bavispe, and their relationship to the more southern distribution of Mexican golden trout (O. chrysogaster) using 11 microsatellite loci. Microsatellite allelic diversity in Mexican trout was high with a mean of 6.6 alleles/locus, average heterozygosity = 0.35, and a mean Fst = 0.43 for all loci combined. Microsatellite data were congruent with previously published mtDNA results showing unique panmictic population structure in the Rio Yaqui trout that differs from Pacific coastal trout and Mexican golden trout. These data also add support for the theory of headwaters transfer of trout across the Continental Divide from tributaries of the Rio de Bavispe into the Rio Casas Grandes. Rio Mayo trout share a close genetic relationship to trout in Rio Yaqui, but sample sizes from the Rio Mayo prevent significant comparisons in this study. Microsatellite analyses show significant allelic frequency differences between Rio Yaqui trout and O. chrysogaster in Sinaloa and Durango Mexico, adding further support for a unique evolutionary status for this group of northwestern Mexican trout.

  4. Laboratory evaluation of a lake trout bioenergetics model

    USGS Publications Warehouse

    Madenjian, Charles P.; O'Connor, Daniel V.

    1999-01-01

    Lake trout Salvelinus namaycush, aged 3 and 6 years and with average weights of 700 and 2,000 g, were grown in laboratory tanks for up to 407 d under a thermal regime similar to that experienced by lake trout in nearshore Lake Michigan. Lake trout were fed alewifeAlosa pseudoharengus and rainbow smelt Osmerus mordax, prey typical of lake trout in Lake Michigan. Of the 120 lake trout used in the experiment, 40 were fed a low ration (0.25% of their body weight per day), 40 were fed a medium ration (0.5% of their body weight per day), and 40 were fed a high ration (ad libitum). We measured consumption and growth, and we compared observed consumption with that predicted by the Wisconsin bioenergetics model. For lake trout fed the medium ration, model predictions for monthly consumption were unbiased. Moreover, predicted cumulative consumption by medium-ration lake trout for the entire experiment (320 d for smaller lake trout and 407 d for larger lake trout) agreed quite well with observed cumulative consumption; predictions were as close as within 0.1 to 5.2% of observed cumulative consumption. Even so, the model consistently overestimated consumption by low-ration fish and underestimated consumption by high-ration fish. The bias was significant in both cases, but was more severe for the low-ration trout. Because the low-ration and high-ration regimes were probably unrealistic for lake trout residing in Lake Michigan and because the model fit our laboratory data rather well for medium-ration trout, we conclude that applying the Wisconsin bioenergetics model to the Lake Michigan lake trout population in order to estimate the amount of prey fish consumed by lake trout each year is appropriate.

  5. eHealth Recruitment Challenges

    ERIC Educational Resources Information Center

    Thompson, Debbe; Canada, Ashanti; Bhatt, Riddhi; Davis, Jennifer; Plesko, Lisa; Baranowski, Tom; Cullen, Karen; Zakeri, Issa

    2006-01-01

    Little is known about effective eHealth recruitment methods. This paper presents recruitment challenges associated with enrolling African-American girls aged 8-10 years in an eHealth obesity prevention program, their effect on the recruitment plan, and potential implications for eHealth research. Although the initial recruitment strategy was…

  6. Erosion of interspecific reproductive barriers resulting from hatchery supplementation of rainbow trout sympatric with cutthroat trout.

    PubMed

    Docker, Margaret F; Dale, Angie; Heath, Daniel D

    2003-12-01

    The frequency of hybridization between cutthroat (Onchorhynchus clarki clarki) and rainbow (O. mykiss irideus) trout from coastal habitats in British Columbia, Canada, was examined in seven populations where the two species are sympatric with no history of rainbow trout stocking and compared with areas where native rainbow trout populations have been supplemented with hatchery fish (three populations). Four nuclear markers were used to identify each species and interspecific hybrids and one mitochondrial marker showed the direction of gene exchange between species. The frequency of hybrids was significantly higher (Fisher exact test, P < 0.001) in river systems where hatchery rainbow trout have been introduced (50.6% hybrids) than in populations where the two species naturally co-occur without supplementation (9.9% hybrids).

  7. Recruiting Blacks into Journalism.

    ERIC Educational Resources Information Center

    Tipton, Leonard; And Others

    Despite significant progress in the recruitment of black journalists, adequate representation of blacks in newsrooms remains an acute concern. The results of (1) statistical monitoring by organizations such as the Newspaper Fund, (2) searching of trade press and academic journal articles for insights into the problem, (3) an open-ended…

  8. Today's Recruitment Trends.

    ERIC Educational Resources Information Center

    Sugarman, Joe

    1996-01-01

    Five trends in the creation of college student recruitment publications are identified: (1) using market research and marketing principles; (2) targeting specific groups; (3) honesty about campus personality and reputation; (4) cost-effectiveness; and (5) creativity in using effective copy and design. (MSE)

  9. Recruiting New Teachers.

    ERIC Educational Resources Information Center

    Camp, William G.; And Others

    1997-01-01

    This special theme issue includes: "How Can We Solve the Teacher Shortage?" (Camp); "A Student's Perspective" (Swafford); "Recruitment" (Dyer, Andreasen); "Top 10 Reasons to Become an Agriculture Teacher and FFA Advisor" (Bembardt, McMaben); "Supply and Demand of Agriculture Teachers since 1965"…

  10. Recruitment. Hello, goodbye.

    PubMed

    Moore, Alison

    2008-07-10

    The UK is "moving to a policy of self-sufficiency" according to the Department of Health. The numbers of new overseas entrants into healthcare, including doctors, nurses and midwives has slumped. Several other countries, including Canada, the US and Australia, are aggressively recruiting from overseas, including from the UK. There is an increasing perception the UK does not want overseas staff.

  11. Population dynamics of Lake Ontario lake trout during 1985-2007

    USGS Publications Warehouse

    Brenden, Travis O.; Bence, James R.; Lantry, Brian F.; Lantry, Jana R.; Schaner, Ted

    2011-01-01

    Lake trout Salvelinus namaycush were extirpated from Lake Ontario circa 1950 owing to commercial and recreational fishing, predation by sea lampreys Petromyzon marinus, and habitat degradation. Since the 1970s, substantial efforts have been devoted to reestablishing a self-sustaining population through stocking, sea lamprey control, and harvest reduction. Although a stocking-supported population has been established, only limited natural reproduction has been detected. Since the 1990s, surveys have indicated a continuing decline in overall abundance despite fairly static stocking levels. We constructed a statistical catch-at-age model to describe the dynamics of Lake Ontario lake trout from 1985 to 2007 and explore what factor(s) could be causing the declines in abundance. Model estimates indicated that abundance had declined by approximately 76% since 1985. The factor that appeared most responsible for this was an increase in age-1 natural mortality rates from approximately 0.9 to 2.5 between 1985 and 2002. The largest source of mortality for age-2 and older fish was sea lamprey predation, followed by natural and recreational fishing mortality. Exploitation was low, harvest levels being uncertain and categorized by length rather than age. Accurate predictions of fishery harvest and survey catch per unit effort were obtained despite low harvest levels by using atypical data (e.g., numbers stocked as an absolute measure of recruitment) and a flexible modeling approach. Flexible approaches such as this might allow similar assessments for a wide range of lightly exploited stocks. The mechanisms responsible for declining age-1 lake trout survival are unknown, but the declines were coincident with an increase in the proportion of stocked fish that were of the Seneca strain and a decrease in the overall stocking rate. It is possible that earlier studies suggesting that Seneca strain lake trout would be successful in Lake Ontario are no longer applicable given the large

  12. Sensitivity of early life stages of white sturgeon, rainbow trout, and fathead minnow to copper.

    PubMed

    Vardy, David W; Oellers, Johanna; Doering, Jon A; Hollert, Henner; Giesy, John P; Hecker, Markus

    2013-01-01

    Populations of white sturgeon (WS; Acipenser transmontanus) are in decline in several parts of the United States and Canada, attributed primarily to poor recruitment caused by degradation of habitats, including pollution with contaminants such as metals. Little is known about sensitivity of WS to contaminants or metals such as copper (Cu). Here, acute (96 h) mortalities of WS early life stages due to exposure to Cu under laboratory conditions are reported. Two standard test species, rainbow trout (Oncorhynchus mykiss) and fathead minnow (Pimephales promelas), were exposed in parallel to determine relative sensitivity among species. Swim-up larvae [15 days post-hatch (dph)] and early juveniles (40-45 dph) of WS were more sensitive to Cu (LC(50) = 10 and 9-17 μg/L, respectively) than were yolksac larvae (8 dph; LC(50) = 22 μg/L) and the later juvenile life stage (100 dph; LC(50) = 54 μg/L). WS were more sensitive to Cu than rainbow trout and fathead minnow at all comparable life stages tested. Yolksac larvae of rainbow trout and fathead minnow were 1.8 and 4.6 times, respectively, more tolerant than WS, while swim-up and juvenile life stages of rainbow trout were between 1.4- and 2.4-times more tolerant than WS. When plotted in a species sensitivity distribution with other fishes, the mean acute toxicity value for early life stage WS was ranked between the 1st and 2nd centile. The WS life stage of greatest Cu sensitivity coincides with the beginning of active feeding and close association with sediment, possibly increasing risk. WS early life stages are sensitive to aqueous copper exposure and site-specific water quality guidelines and criteria should be evaluated closely to ensure adequate protection.

  13. Predator nonconsumptive effects on prey recruitment weaken with recruit density.

    PubMed

    Ellrich, Julius A; Scrosati, Ricardo A; Molis, Markus

    2015-03-01

    We investigated the nonconsumptive effects (NCEs) of predatory dogwhelks (Nucella lapillus) on intertidal barnacle (Semibalanus balanoides) recruitment through field experiments on the Gulf of St. Lawrence coast and the Atlantic coast of Nova Scotia, Canada. We studied the recruitment seasons (May-June) of 2011 and 2013. In 2011, the Gulf coast had five times more nearshore phytoplankton (food for barnacle larvae and recruits) during the recruitment season and yielded a 58% higher barnacle recruit density than the Atlantic coast at the end of the recruitment season. In 2013, phytoplankton levels and barnacle recruit density were similar on both coasts and also lower than for the Gulf coast in 2011. Using the comparative-experimental method, the manipulation of dogwhelk presence (without allowing physical contact with prey) revealed that dogwhelk cues limited barnacle recruitment under moderate recruit densities (Atlantic 2011/2013 and Gulf 2013) but had no effect under a high recruit density (Gulf 2011). Barnacle recruits attract settling larvae through chemical cues. Thus, the highest recruit density appears to have neutralized dogwhelk effects. This study suggests that the predation risk perceived by settling larvae may decrease with increasing recruit density and that prey food supply may indirectly influence predator NCEs on prey recruitment.

  14. Rhombencephalitis caused by Listeria monocytogenes in a pastured bull.

    PubMed

    Matto, Carolina; Varela, Gustavo; Mota, María Inés; Gianneechini, Ruben; Rivero, Rodolfo

    2017-03-01

    A pastured 2-y-old cross-breed bull developed brainstem encephalitis (rhombencephalitis); Listeria monocytogenes was isolated from the brain. In the brainstem, there was perivascular cuffing, multiple microabscesses, and positive immunostaining for L. monocytogenes. Samples of bovine feces, water, feedstuffs, milking parlor soil, and bulk tank milk were collected from the dairy farm. Seven isolates of the genus Listeria were obtained, 6 of L. innocua and 1 of L. monocytogenes, which was found in the pasture where the bull grazed. Both isolates belonged to serotype 4b and were positive for internalins A, C, and J. According to the DNA fragment patterns of pulsed-field gel electrophoresis, the isolates were closely related. The source of infection was the pasture, implying that listeriosis should not be discounted in cases with compatible clinical signs but the absence of silage feeding.

  15. Bull breeding soundness, semen evaluation and cattle productivity.

    PubMed

    Chenoweth, P J; McPherson, F J

    2016-06-01

    The bull breeding soundness evaluation (BBSE) has evolved as a cost-effective veterinary procedure which provides benefits such as risk-reduction and improvements in strategic bull usage, herd fertility and economics. Semen evaluation is an important component of the BBSE when performed appropriately; a consideration that is increasingly addressed by third party andrology laboratories. The combination of competent physical/reproductive exams (including scrotal circumference measurements) and semen evaluations can contribute greatly to the fertility and economics of individual herds as well as adding to understanding of those factors which affect cattle fertility. Despite such advantages, there remain challenges in achieving full acceptance of BBSEs, particularly by the dairy industry and in developing countries.

  16. Importance of tributary streams for rainbow trout reproduction: insights from a small stream in Georgia and a bi-genomic approach

    USGS Publications Warehouse

    Lee, D.; Lack, Justin B.; Van Den Bussche, Ronald A.; Long, James M.

    2012-01-01

    Tributaries of tailwater fisheries in the southeastern USA have been used for spawning by stocked rainbow trout (Oncorhynchus mykiss), but their importance may have been underestimated using traditional fish survey methods such as electrofishing and redd counts. We used a bi-genomic approach, mitochondrial DNA sequences and nuclear microsatellite loci, to estimate the number of spawning adults in one small tributary (Cabin Creek) of the Chattahoochee River, Georgia, where rainbow trout are known to spawn and have successful recruitment. We extracted and analysed DNA from seven mature male rainbow trout and four juveniles that were captured in February 2006 in Cabin Creek and from 24 young-of-year (YOY) trout that were captured in April 2006. From these samples, we estimated that 24 individuals were spawning to produce the amount of genetic variation observed in the juveniles and YOY, although none of the mature males we sampled were indicated as sires. Analysis of the mitochondrial D-loop region identified four distinct haplotypes, suggesting that individuals representing four maternal lineages contributed to the offspring. Our analyses indicated that many more adults were spawning in this system than previously estimated with direct count methods and provided insight into rainbow trout spawning behavior.

  17. 75 FR 38768 - Ashley National Forest, UT, High Uintas Wilderness-Colorado River Cutthroat Trout Habitat...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-06

    ... Wilderness--Colorado River Cutthroat Trout Habitat Enhancement AGENCY: Forest Service, USDA. ACTION: Notice... Colorado River Cutthroat Trout Conservation Agreement and Strategy. This action would help the Forest Service demonstrate support and commitment to Colorado River cutthroat trout conservation...

  18. Lake trout in northern Lake Huron spawn on submerged drumlins

    USGS Publications Warehouse

    Riley, Stephen C.; Binder, Thomas; Wattrus, Nigel J.; Faust, Matthew D.; Janssen, John; Menzies, John; Marsden, J. Ellen; Ebener, Mark P.; Bronte, Charles R.; He, Ji X.; Tucker, Taaja R.; Hansen, Michael J.; Thompson, Henry T.; Muir, Andrew M.; Krueger, Charles C.

    2014-01-01

    Recent observations of spawning lake trout Salvelinus namaycush near Drummond Island in northern Lake Huron indicate that lake trout use drumlins, landforms created in subglacial environments by the action of ice sheets, as a primary spawning habitat. From these observations, we generated a hypothesis that may in part explain locations chosen by lake trout for spawning. Most salmonines spawn in streams where they rely on streamflows to sort and clean sediments to create good spawning habitat. Flows sufficient to sort larger sediment sizes are generally lacking in lakes, but some glacial bedforms contain large pockets of sorted sediments that can provide the interstitial spaces necessary for lake trout egg incubation, particularly if these bedforms are situated such that lake currents can penetrate these sediments. We hypothesize that sediment inclusions from glacial scavenging and sediment sorting that occurred during the creation of bedforms such as drumlins, end moraines, and eskers create suitable conditions for lake trout egg incubation, particularly where these bedforms interact with lake currents to remove fine sediments. Further, these bedforms may provide high-quality lake trout spawning habitat at many locations in the Great Lakes and may be especially important along the southern edge of the range of the species. A better understanding of the role of glacially-derived bedforms in the creation of lake trout spawning habitat may help develop powerful predictors of lake trout spawning locations, provide insight into the evolution of unique spawning behaviors by lake trout, and aid in lake trout restoration in the Great Lakes.

  19. Bilateral congenital lacrimal fistula in a Brown Swiss bull.

    PubMed

    Braun, U; Spiess, B; Matheis, F; Schnetzler, C; Trösch, L; Drögemüller, C; Gerspach, C

    2012-03-01

    A five-year-old Brown Swiss bull was referred to the Department of Farm Animals, University of Zurich, because of bilateral epiphora that was unresponsive to treatment. Clinical examination revealed a fistulous opening medial to the medial canthus of both eyes and mucopurulent discharge from both openings. Attempts to flush the nasolacrimal duct via the lacrimal points resulted in the fluid exiting via the fistulous opening. Retrograde flushing of the nasolacrimal duct from the nasolacrimal opening resulted in the flush fluid flowing back out the nasolacrimal opening. Bilateral lacrimal fistula medial to the medial canthus of the eye was diagnosed based on the findings. The same anomaly was diagnosed a year later in 4 related female animals referred to our Department for other reasons. Three of the cases were sired by the bull described above and one was sired by his half-brother. Therefore, an autosomal recessive mode of inheritance of this anomaly was assumed. Clinical, epidemiological and molecular studies of the offspring of both bulls are underway to further investigate this anomaly.

  20. Purification and properties of hyaluronidase from bull sperm.

    PubMed

    Yang, C H; Srivastava, P N

    1975-01-10

    Hyaluronidase from bull sperm was fractionated by ammonium sulfate and further purified by DEAE-cellulose and Sephadex chromatography. The highly purified hyaluronidase preparation showed 2,370 units per mg of protein (68,730 N.F. units per mg of protein), i.e. 182-fold purification. Disc gel electrophoresis showed one major component. The molecular weight of bull sperm hyaluronidase was 62,000 by sodium dodecyl sulfate gel electrophoresis. Hyaluronidase from bull sperm has optimum activity at pH 3.8 and an absolute requirement for cations. Kplus and Naplus have a greater effect than Ca2plus, Mg2plus, and Mn2plus, whereas Co2plus, Cu2plus, and Zn2plus do not affect the enzyme activity. Purified preparations are less stable than crude extracts stored frozen at minus 15 degrees. Km of hyaluronidase with hyaluronic acid as substrate is 3.7 mg per ml and Vmax is 2.4 mumol per min by Hofstee plot.

  1. Proteomic identification of rainbow trout sperm proteins.

    PubMed

    Nynca, Joanna; Arnold, Georg J; Fröhlich, Thomas; Otte, Kathrin; Ciereszko, Andrzej

    2014-06-01

    Proteomics represents a powerful tool for the analysis of fish spermatozoa, since these cells are transcriptionally inactive. The aim of the present study was to generate an inventory of the most prominent rainbow trout sperm proteins by SDS-PAGE prefractionation combined with nano-LC-MS/MS based identification. This study provides the first in-depth analysis of the rainbow trout sperm proteome, with a total of 206 identified proteins. We found that rainbow trout spermatozoa are equipped with functionally diverse proteins related to energetic metabolism, signal transduction, protein turnover, transport, cytoskeleton, oxidative injuries, and stress and reproduction. The availability of a catalog of rainbow trout sperm proteins provides a crucial tool for the understanding of fundamental molecular processes in fish spermatozoa, for the ongoing development of novel markers of sperm quality and for the optimization of short- and long-term sperm preservation procedures. The MS data are available at ProteomeXchange with the dataset identifier PXD000355 and DOI 10.6019/PXD000355.

  2. Brook Trout Back in Aaron Run

    EPA Pesticide Factsheets

    Following a series of acid mine drainage (AMD) projects funded largely by EPA’s Clean Water Act Section 319 non-point source program, the pH level in Aaron Run is meeting Maryland’s water quality standard – and the brook trout are back.

  3. Lake trout restoration in the Great Lakes: stock-size criteria for natural reproduction

    USGS Publications Warehouse

    Selgeby, James H.; Bronte, Charles R.; Brown, Edward H.; Hansen, Michael J.; Holey, Mark E.; VanAmberg, Jan P.; Muth, Kenneth M.; Makauskas, Daniel B.; Mckee, Patrick; Anderson, David M.; Ferreri, C. Paola; Schram, Stephen T.

    1995-01-01

    We examined the question of whether the lake trout restoration program in the Great Lakes has developed brood stocks of adequate size to sustain natural reproduction. Stock size criteria were developed from areas of the Great Lakes where natural reproduction has been successful (defined as detection of age-1 or older recruits by assessment fishing). We contrasted them with stocks in areas with no natural reproduction. Based on the relative abundance of spawners measured in the fall and the presence or absence of natural reproduction in 24 areas of the Great Lakes, we found three distinct sets of lake trout populations. In seven areas of successful natural reproduction, the catch-per-unit-effort (CPE) of spawners ranged from 17 to 135 fish/305 m of gillnet. Stock sizes in these areas were used as a gauge against which stocks in other areas were contrasted. We conclude that stock densities of 17-135 fish/305 m of gill net are adequate for natural reproduction, provided that all other requirements are met. No natural reproduction has been detected in seven other areas, where CPEs of spawners ranged from only 3 to 5 fish/305 m. We conclude that spawning stocks of only 3-5 fish/305 m of net are inadequate to develop measurable natural reproduction. Natural reproduction has also not been detected in ten areas where CPEs of spawners ranged from 43 to 195 fish/305 m of net. We conclude that spawning stocks in these ten areas were adequate to sustain natural reproduction, but that some factor other than parental stock size prevented recruitment of wild lake trout.

  4. Infectious pancreatic necrosis the trout farmers' dilemma

    USGS Publications Warehouse

    Parisot, T.J.

    1965-01-01

    Induction of the innate immune pathways is critical for early anti-viral defense but there is limited understanding of how teleost fish recognize viral molecules and activate these pathways. In mammals, Toll-like receptors (TLR) 7 and 8 bind single-stranded RNA of viral origin and are activated by synthetic anti-viral imidazoquinoline compounds. Herein, we identify and describe the rainbow trout (Oncorhynchus mykiss) TLR7 and TLR8 gene orthologs and their mRNA expression. Two TLR7/8 loci were identified from a rainbow trout bacterial artificial chromosome (BAC) library using DNA fingerprinting and genetic linkage analyses. Direct sequencing of two representative BACs revealed intact omTLR7and omTLR8a1 open reading frames (ORFs) located on chromosome 3 and a second locus on chromosome 22 that contains an omTLR8a2 ORF and a putative TLR7pseudogene. We used the omTLR8a1/2 nomenclature for the two trout TLR8 genes as phylogenetic analysis revealed that they and all the other teleost TLR8 genes sequenced to date are similar to the zebrafish TLR8a, but are distinct from the zebrafish TLR8b. The duplicated trout loci exhibit conserved synteny with other fish genomes extending beyond the tandem of TLR7/8 genes. The trout TLR7 and 8a1/2 genes are composed of a single large exon similar to all other described TLR7/8 genes. The omTLR7 ORF is predicted to encode a 1049 amino acid (aa) protein with 84% similarity to the Fugu TLR7and a conserved pattern of predicted leucine-rich repeats (LRR). The omTLR8a1 andomTLR8a2 are predicted to encode 1035- and 1034-aa proteins, respectively, and have 86% similarity to each other. omTLR8a1 is likely the ortholog of the only Atlantic salmonTLR8 gene described to date as they have 95% aa sequence similarity. The tissue expression profiles of omTLR7, omTLR8a1 and omTLR8a2 in healthy trout were highest in spleen tissue followed by anterior and then posterior kidney tissues. Rainbow trout anterior kidney leukocytes produced elevated levels of

  5. Bull selection and use in northern Australia. 5. Social behaviour and management.

    PubMed

    Fordyce, G; Fitzpatrick, L A; Cooper, N J; Doogan, V J; De Faveri, J; Holroyd, R G

    2002-05-15

    Calf output of bulls was derived using DNA typing for paternity following multiple-sire mating at two sites in northern Australia. At Swan's Lagoon Beef Cattle Research Station, 12, mixed-age, Brahman cross bulls were continuously mated with an average of 325 females in a 22km2 open-savannah paddock. Water was available in two troughs. Behaviour of the bulls and location of cows were monitored. At Kamilaroi Station, 2- to 2.5-year-old Brahman bulls were introduced to the study. Twenty-four bulls (HIGH%) were mated in an 84km2 paddock for 3.5 months to 411 heifers in 1995/1995 and for 4.5 months to 350 heifers and 320 first-lactation cows in 1995/1996. A second group of 10 bulls (LOW%) selected on reproductive soundness was mated concurrently in a neighbouring 60km2 paddock to 411 heifers in 1995/1995 and to 350 heifers and 298 first-lactation cows in 1995/1996. In each paddock in both years, 300-350 females were expected to cycle during mating. Both paddocks were flat and semi-forested and water was available only at troughs. At both sites, detailed physical and reproductive examinations of all bulls were conducted prior to and post-mating.Calf output of individual bulls was highly variable but repeatable (r=0.6-0.7) between years. Up to 90% of the 270-380 calves resulting from each mating were sired by between 6 and 8 bulls. Reducing from 3.7 to 2.8% bulls:females at Swan's Lagoon did not delay conceptions. At Kamilaroi, reproductively sound bulls achieved an estimated 5-6 conceptions per week over the peak mating period when sufficient cycling females were available. Differences in pregnancy rates between paddocks appeared due to differences in nutrition and it appeared that conceptions were not delayed with LOW% vs. HIGH% bulls. Variance between bulls in calf output was substantially lower when fewer bulls were used. Bull attrition occurred each year in the HIGH% paddock but not in the LOW% paddock. Calf output was unrelated to body condition of bulls. Seven of

  6. MBA Recruitment Task Group

    DTIC Science & Technology

    2003-02-05

    talented, recent MBA graduates from top-tier U.S. business schools . These graduates bring new ideas, energy and private sector management...sets and school performance may be different, all Fellows are expected to be recent graduates of top-tier business schools who will be performing in...the “CEO/Ambassador” to one of the target business schools where DoD is establishing a physical recruiting presence. The person’s role would be to

  7. Recruiting and Retaining Cyberwarriors

    DTIC Science & Technology

    2008-02-07

    challenge is further exacerbated by a new generation , commonly referred to as Millennials , now coming into the workplace. The Millennials have...these growing recruitment and retention challenges along with the many generational differences of the Millennials in an attempt to provide some...is further exacerbated by a new generation now coming into the workplace. This new generation , commonly referred to as Millennials , has different

  8. Navy Enlisted Recruiting: Alternatives for Improving Recruiter Productivity

    DTIC Science & Technology

    2013-03-01

    Instruction CR Chief Recruiter CRF Career Recruiting Force CS Culinary Specialist CT Command Trainer CTI Cryptologic Technician...8, Aviation Machinist Mates (AD), Aviation Structural Mechanic (AM), Culinary Specialists (CS), and Fire Controlman (FC) had the highest average

  9. Inconsistent identification of pit bull-type dogs by shelter staff.

    PubMed

    Olson, K R; Levy, J K; Norby, B; Crandall, M M; Broadhurst, J E; Jacks, S; Barton, R C; Zimmerman, M S

    2015-11-01

    Shelter staff and veterinarians routinely make subjective dog breed identification based on appearance, but their accuracy regarding pit bull-type breeds is unknown. The purpose of this study was to measure agreement among shelter staff in assigning pit bull-type breed designations to shelter dogs and to compare breed assignments with DNA breed signatures. In this prospective cross-sectional study, four staff members at each of four different shelters recorded their suspected breed(s) for 30 dogs; there was a total of 16 breed assessors and 120 dogs. The terms American pit bull terrier, American Staffordshire terrier, Staffordshire bull terrier, pit bull, and their mixes were included in the study definition of 'pit bull-type breeds.' Using visual identification only, the median inter-observer agreements and kappa values in pair-wise comparisons of each of the staff breed assignments for pit bull-type breed vs. not pit bull-type breed ranged from 76% to 83% and from 0.44 to 0.52 (moderate agreement), respectively. Whole blood was submitted to a commercial DNA testing laboratory for breed identification. Whereas DNA breed signatures identified only 25 dogs (21%) as pit bull-type, shelter staff collectively identified 62 (52%) dogs as pit bull-type. Agreement between visual and DNA-based breed assignments varied among individuals, with sensitivity for pit bull-type identification ranging from 33% to 75% and specificity ranging from 52% to 100%. The median kappa value for inter-observer agreement with DNA results at each shelter ranged from 0.1 to 0.48 (poor to moderate). Lack of consistency among shelter staff indicated that visual identification of pit bull-type dogs was unreliable.

  10. Joint disorder; a contributory cause to reproductive failure in beef bulls?

    PubMed

    Persson, Ylva; Söderquist, Lennart; Ekman, Stina

    2007-11-05

    The lame sire, unsound for breeding, can cause substantial economic loss due to reduced pregnancies in the beef-producing herd. To test the hypothesis that joint disorder is a possible cause of infertility in beef sires, right and left hind limb bones from 34 beef sires were examined postmortem to identify lesions in the femorotibial, femoropatellar (stifle), tarsocrural, talocalcaneus, and proximal intertarsal (tarsal) joints. The bulls were slaughtered during or after the breeding season due to poor fertility results. Aliquots of the cauda epididymal contents taken postmortem from 26 bulls were used for sperm morphology evaluation. As a control, hind limbs (but no semen samples) from 11 beef bulls with good fertility results were included. Almost all infertile bulls (30/34) had lesions in at least one joint. Twenty-eight bulls (28/30, 93%) had lesions in the stifle joint, and 24 (24/28, 86%) of these were bilateral. Fourteen bulls (14/30, 47%) had lesions in the tarsal joint, and 10 (10/14, 71%) of these were bilateral. Four bulls (4/34, 12%) had no lesions, three bulls (3/34, 9%) had mild osteoarthritis (OA), 5 (5/34, 15%) moderate OA, 17 (17/34, 50%) severe OA and 5 (5/34, 15%) deformed OA. Almost all OA lesions (97%) were characterized as lesions secondary to osteochondrosis dissecans. All the bulls with satisfactory sperm morphology (n = 12/34) had joint lesions, with mostly severe or deformed bilateral lesions (83%). Consequently, the most likely cause of infertility in these 12 bulls was joint disease. Almost all control bulls (10/11) had OA lesions, but most of them were graded as mild (55%) or moderate (36%). None of the control bulls had severe lesions or deformed OA. We suggest that joint lesions should be taken into consideration as a contributory cause of reproductive failure in beef sires without symptoms of lameness.

  11. Influence of Wave Refraction on Coastal Geomorphology-Bull Island to Isle of Palms, South Carolina.

    DTIC Science & Technology

    1978-12-01

    coast from Bull Island to the Isle of Palms . REFRAC, a computerized wave-refracti program developed for this study, generates refraction diagrams...Geomorphology Bull Island to Isle of Palms , South Carolina Cary Fico Coastal Research Division Department of Geology Uo 0O University of South Carolina Columnbia...South Carolina 29208 80 :i1 13 U23 INFLUENCE OF WAVE REFRACTION ON COASTAL GEOMORPHOLOGY -- BULL ISLAND TO ISLE OF PALMS , SOUTH CAROLINA by Cary Fico

  12. Generational Recruiting: Applying Generational Theory to Tactical Level Recruiting

    DTIC Science & Technology

    2013-04-24

    theory at the tactical level of recruiting, recruiters must be mindful of the socio-economic environment and influences that shaped the peer personality......Command to apply generational theory at the ’tactical level’ of canvassing recruiters, just as MCRC applies generational theory in its expertly informed

  13. The Students-Recruiting-Students Undergraduate Engineering Recruiting Programme.

    ERIC Educational Resources Information Center

    Gattis, Carol; Nachtmann, Heather; Youngblood, Alisha D.

    2003-01-01

    Describes the Students-Recruiting-Students (SRS) program developed to recruit high school students into the Industrial Engineering Department at the University of Arkansas. Presents four phases of the program along with seven years of program results. Encourages successful development of similar recruiting programs. (KHR)

  14. Fertility aspects in yearling beef bulls grazing endophyte-infected tall fescue pastures.

    PubMed

    Schuenemann, G M; Edwards, J L; Hopkins, F M; Rohrbach, N R; Adair, H S; Scenna, F N; Waller, J C; Oliver, J W; Saxton, A M; Schrick, F N

    2005-01-01

    During a 2-year study, yearling beef bulls were used to determine the effects of grazing on endophyte-infected tall fescue on endocrine profiles, semen quality and fertilisation potential. Bulls were allotted to graze tall fescue pastures infected with Neotyphodium coenophialum (E+; n = 20 per year) or Jesup/MaxQ (Pennington Seed, Atlanta, GA, USA; NTE; n = 10 per year). Bulls were grouped by scrotal circumference (SC), bodyweight (BW), breed composites and age to graze tall fescue pastures from mid-November until the end of June (within each year). Blood samples, BW, SC and rectal temperatures (RT) were collected every 14 days. Semen was collected from bulls every 60 days by electroejaculation and evaluated for motility and morphology. The developmental competence of oocytes fertilised in vitro with semen from respective treatments was determined. Bulls grazing E+ pastures had decreased BW gain (P < 0.01), increased overall RT (P < 0.01) and decreased prolactin (P < 0.01) compared with animals grazing NTE pastures. Neither percentage of normal sperm morphology nor motility differed between bulls grazed on the two pasture types. Semen from E+ bulls demonstrated decreased cleavage rates (P = 0.02) compared with semen from NTE bulls. However, development of cleaved embryos to the eight-cell and blastocyst stages did not differ between the two groups. In conclusion, semen from bulls grazing E+ tall fescue resulted in decreased cleavage rates in vitro, which may lower reproductive performance owing to reduced fertilisation ability.

  15. Enhanced early-life nutrition promotes hormone production and reproductive development in Holstein bulls.

    PubMed

    Dance, Alysha; Thundathil, Jacob; Wilde, Randy; Blondin, Patrick; Kastelic, John

    2015-02-01

    Holstein bull calves often reach artificial insemination centers in suboptimal body condition. Early-life nutrition is reported to increase reproductive performance in beef bulls. The objective was to determine whether early-life nutrition in Holstein bulls had effects similar to those reported in beef bulls. Twenty-six Holstein bull calves were randomly allocated into 3 groups at approximately 1 wk of age to receive a low-, medium-, or high-nutrition diet, based on levels of energy and protein, from 2 to 31 wk of age. Calves were on their respective diets until 31 wk of age, after which they were all fed a medium-nutrition diet. To evaluate secretion profiles and concentrations of blood hormones, a subset of bulls was subjected to intensive blood sampling every 4 wk from 11 to 31 wk of age. Testes of all bulls were measured once a month; once scrotal circumference reached 26cm, semen collection was attempted (by electroejaculation) every 2 wk to confirm puberty. Bulls were maintained until approximately 72 wk of age and then slaughtered at a local abattoir. Testes were recovered and weighed. Bulls fed the high-nutrition diet were younger at puberty (high=324.3 d, low=369.3 d) and had larger testes for the entire experimental period than bulls fed the low-nutrition diet. Bulls fed the high-nutrition diet also had an earlier and more substantial early rise in LH than those fed the low-nutrition diet and had increased concentrations of insulin-like growth factor-I (IGF-I) earlier than the bulls fed the low-nutrition diet. Furthermore, we detected a temporal association between increased IGF-I concentrations and an early LH rise in bulls fed the high-nutrition diet. Therefore, we inferred that IGF-I had a role in regulating the early gonadotropin rise (in particular, LH) and thus reproductive development of Holstein bulls. Overall, these results support our hypothesis that Holstein bull calves fed a high-nutrition diet reach puberty earlier and have larger testes than

  16. Evaluating temperature regimes for protection of brown trout

    USGS Publications Warehouse

    Armour, Carl L.

    1994-01-01

    Geographic distribution and population success of brown trout (Salmo trutta) are affected by temperature regimes. Concepts are presented for evaluating alternative temperature regimes for brown trout based on published temperature information and professional judgment. Temperature information from the literature is included for spawning runs, spawning, egg and larval development, growth, and other subjects. The objective is to aid biologists in evaluating alternative temperature regimes so as to select those that will protect and enhance environmental quality for brown trout.

  17. Comparative proteomic analysis of Taurine, Indicine, and crossbred (Bos taurus × Bos indicus) bull spermatozoa for identification of proteins related to sperm malfunctions and subfertility in crossbred bulls.

    PubMed

    Muhammad Aslam, Munchakkal Kather; Kumaresan, Arumugam; Rajak, Shailendra Kumar; Tajmul, Md; Datta, Tirtha Kumar; Mohanty, Tushar Kumar; Srinivasan, Alagiri; Yadav, Savita

    2015-09-01

    Subfertility is one of the most common problems observed among Taurine × Indicine crossbred bulls in tropical countries; however, the etiology remain unknown in most of the cases. In present study, we compared the proteomic profile of spermatozoa from crossbred bulls (Bos taurus × Bos indicus) against their purebred parent lines (Holstein Friesian [Taurine] and Tharparkar [Indicine]) to find out alteration in expressions of proteins, if any. The proteomic profiles of freshly ejaculated spermatozoa from these breeds were compared by two-dimensional difference gel electrophoresis, and differentially expressed proteins were identified through mass spectrometry. It was observed that compared to Holstein Friesian, nine proteins were underexpressed and eight proteins were overexpressed (P < 0.05) in the spermatozoa of crossbred bulls. Similarly, four proteins were overexpressed and four proteins were underexpressed (P < 0.05) in the spermatozoa of crossbred bulls compared to Tharparkar bulls. In concurrent three breed comparison, 14 proteins were found to be differentially expressed (P < 0.05) between these breeds. From the findings of the study, it is apparent that the expression levels of several functionally significant proteins are either upregulated or downregulated in spermatozoa of crossbred bulls, which might be related to high incidence of subfertility in these bulls.

  18. Nutritionally induced hepatomagenesis of rainbow trout (Salmo gairdneri)

    USGS Publications Warehouse

    1967-01-01

    Hepatoma in commercially reared rainbow trout (Salmo gairdneri) was first seen at this laboratory in April of 1960. The subsequent discovery of it in near epizootic proportions in other hatchery-reared rainbow trout and cutthroat trout (S. clarki) populations throughout the United States precipitated extensive research by numerous agencies. Although the liver neoplasm in trout had been previously noted here (Haddow and Blake, 1933; Nigrelli, 1954; Nigrelli and Jakowska, 1955) and abroad (Cudkowicz and Scolari, 1955) occurrences of it in such proportions had not been reported previously in this country.

  19. Army Recruiting Resourcing System.

    DTIC Science & Technology

    1990-09-01

    Sheridan, Illinois 60037-6090 REPORT DOCUMENTATION PAGE OMO No. 070虨 I.& Mrw ung U btOfl tOf thti (CM .; 9 Of nOMToMt,0* Mt e,,tiSO w &rIK" 1 OUr...are those of the author and should not be construed as an official Department of the Army policy or position, unless so designated by other...changes in policies , regulations, or statutes that affect recruiting. Those interviewed within the DA staff (DCSPER, PA&E, and DAB personnel) believe there

  20. Preparing Alumni for Student Recruitment.

    ERIC Educational Resources Information Center

    Mount, Brian

    As recruitment budgets continue to tighten and with fewer colleges reporting application increases for their freshmen classes, enrollment managers must continue to explore all potential sources of recruitment talent. Alumni are often an underutilized or sometimes poorly utilized resource in recruitment efforts. Younger alumni, for example, may…

  1. Kootenai River Fisheries Investigations: Salmonid Studies Project Progress Report, 2007-2008 Annual Report.

    SciTech Connect

    Paragamian, Vaughn L.; Walters, Jody; Maiolie, Melo

    2009-04-09

    This research report addresses bull trout Salvelinus confluentus and Redband trout Oncorhynchus mykiss redd surveys, population monitoring, trout distribution, and abundance surveys in the Kootenai River drainage of Idaho. The bull trout is one of several sport fish native to the Kootenai River, Idaho that no longer supports a fishery. Because bull trout are listed under the Endangered Species Act, population data will be vital to monitoring status relative to recovery goals. Thirty-three bull trout redds were found in North and South Callahan creeks and Boulder Creek in 2007. This is a decrease from 2006 and 2005 and less than the high count in 2003. However, because redd numbers have only been monitored since 2002, the data series is too short to determine bull trout population trends based on redd counts. Redband trout still provide an important Kootenai River sport fishery, but densities are low, at least partly due to limited recruitment. The redband trout proportional stock density (PSD) in 2007 increased from 2006 for a second year after a two-year decline in 2004 and 2005. This may indicate increased recruitment to or survival in the 201-305 mm length group due to the minimum 406 mm (16 inches) length limit initiated in 2002. We conducted 13 redd surveys and counted 44 redband trout redds from May 7 to June 3, 2007 in a 3.8 km survey reach on Twentymile Creek. We surveyed streams in the Kootenai River valley to look for barriers to trout migration. Man-made barriers, for at least part of the year, were found on Caboose, Debt, Fisher, and Twenty Mile creeks. Removing these barriers would increase spawning and rearing habitat for trout and help to restore trout fisheries in the Kootenai River.

  2. Landscape-scale evaluation of asymmetric interactions between Brown Trout and Brook Trout using two-species occupancy models

    USGS Publications Warehouse

    Wagner, Tyler; Jefferson T. Deweber,; Jason Detar,; John A. Sweka,

    2013-01-01

    Predicting the distribution of native stream fishes is fundamental to the management and conservation of many species. Modeling species distributions often consists of quantifying relationships between species occurrence and abundance data at known locations with environmental data at those locations. However, it is well documented that native stream fish distributions can be altered as a result of asymmetric interactions between dominant exotic and subordinate native species. For example, the naturalized exotic Brown Trout Salmo trutta has been identified as a threat to native Brook Trout Salvelinus fontinalis in the eastern United States. To evaluate large-scale patterns of co-occurrence and to quantify the potential effects of Brown Trout presence on Brook Trout occupancy, we used data from 624 stream sites to fit two-species occupancy models. These models assumed that asymmetric interactions occurred between the two species. In addition, we examined natural and anthropogenic landscape characteristics we hypothesized would be important predictors of occurrence of both species. Estimated occupancy for Brook Trout, from a co-occurrence model with no landscape covariates, at sites with Brown Trout present was substantially lower than sites where Brown Trout were absent. We also observed opposing patterns for Brook and Brown Trout occurrence in relation to percentage forest, impervious surface, and agriculture within the network catchment. Our results are consistent with other studies and suggest that alterations to the landscape, and specifically the transition from a forested catchment to one that contains impervious surface or agriculture, reduces the occurrence probability of wild Brook Trout. Our results, however, also suggest that the presence of Brown Trout results in lower occurrence probability of Brook Trout over a range of anthropogenic landscape characteristics, compared with streams where Brown Trout were absent.

  3. Evaluation of bull prolificacy on commercial beef cattle ranches using DNA paternity analysis.

    PubMed

    Van Eenennaam, A L; Weber, K L; Drake, D J

    2014-06-01

    SNP-based DNA testing was used to assign paternity to 5,052 calves conceived in natural service multisire breeding pastures from 3 commercial ranches in northern California representing 15 calf crops over 3 yr. Bulls present for 60 to 120 d at a 25:1 cow to bull ratio in both fall and spring breeding seasons in ∼40 ha or smaller fenced breeding pastures sired a highly variable (P < 0.001) number of calves (Ncalf), ranging from 0 (4.4% of bulls present in any given breeding season) to 64 calves per bull per breeding season, with an average of 18.9 ± 13.1. There was little variation in Ncalf among ranches (P = 0.90), years (P = 0.96), and seasons (P = 0.94). Bulls varied widely (P < 0.01) in the average individual 205-d adjusted weaning weight (I205) of progeny, and I205 varied between years (P < 0.01) and seasons (P < 0.01) but not ranches (P = 0.29). The pattern for cumulative total 205-d adjusted weaning weight of all progeny sired by a bull (T205) was highly correlated to Ncalf, with small differences between ranches (P = 0.35), years (P = 0.66), and seasons (P = 0.20) but large differences (P < 0.01) between bulls, ranging from an average of 676 to 8,838 kg per bull per calf crop. The peak Ncalf occurred at about 5 yr of age for bulls ranging from 2 to 11 yr of age. Weekly conception rates as assessed by date of calving varied significantly and peaked at wk 3 of the calving season. The distribution of calves born early in the calving season was disproportionately skewed toward the highly prolific bulls. The DNA paternity testing of the subset of those calves born in wk 3 of the calving season was highly predictive of overall bull prolificacy and may offer a reduced-cost DNA-based option for assessing prolificacy. Prolificacy of young bulls in their first breeding season was positively linearly related (P < 0.05) to subsequent breeding seasons, explaining about 20% of the subsequent variation. Prolificacy was also positively linearly related (P < 0.05) to

  4. Biotic and abiotic factors related to rainbow smelt recruitment in the Wisconsin waters of Lake Superior, 1978-1997

    USGS Publications Warehouse

    Hoff, Michael H.

    2004-01-01

    Lake Superior rainbow smelt (Osmerus mordax) recruitment to 12-13 months of age in the Wisconsin waters of Lake Superior varied by a factor of 9.3 during 1978-1997. Management agencies have sought models that accurately predict recruitment, but no satisfactory models had previously been developed. In this study, modeling was conducted to determine which factors best explained recruitment variability. The Ricker stock-recruitment model derived from only the paired stock and recruit data accounted for 63% of the variability in recruitment data. The functional relationship that accounted for the greatest amount of recruitment variation (81%) included rainbow smelt stock size, May rainfall, and bloater (Coregonus hoyi) biomass. Model results were interpreted to mean that recruitment was affected negatively by increased river flows from increased rainfall, and affected positively by the biomass of bloater, and those results were interpreted to mean that bloater mediated the effects of lake trout predation on rainbow smelt recruits. Model results were also interpreted to mean that stock size caused compensatory, density-dependent mortality on rainbow smelt recruits. Correlations observed here may be of value to managers seeking approaches to either enhance or control populations of this species, which is not indigenous to the Great Lakes.

  5. A trial of two trouts: Comparing the impacts of rainbow and brown trout on a native galaxiid

    USGS Publications Warehouse

    Young, K.A.; Dunham, J.B.; Stephenson, J.F.; Terreau, A.; Thailly, A.F.; Gajardo, G.; de Leaniz, C. G.

    2010-01-01

    Rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta are the world's two most widespread exotic fishes, dominate the fish communities of most cold-temperate waters in the southern hemisphere and are implicated in the decline and extirpation of native fish species. Here, we provide the first direct comparison of the impacts of rainbow and brown trout on populations of a native fish by quantifying three components of exotic species impact: range, abundance and effect. We surveyed 54 small streams on the island of Chilo?? in Chilean Patagonia and found that the rainbow trout has colonized significantly more streams and has a wider geographic range than brown trout. The two species had similar post-yearling abundances in allopatry and sympatry, and their abundances depended similarly on reach-level variation in the physical habitat. The species appeared to have dramatically different effects on native drift-feeding Aplochiton spp., which were virtually absent from streams invaded by brown trout but shared a broad sympatric range with rainbow trout. Within this range, the species' post-yearling abundances varied independently before and after controlling for variation in the physical habitat. In the north of the island, Aplochiton spp. inhabited streams uninvaded by exotic trouts. Our results provide a context for investigating the mechanisms responsible for apparent differences in rainbow and brown trout invasion biology and can help inform conservation strategies for native fishes in Chilo?? and elsewhere. ?? 2010 The Authors. Journal compilation ?? 2010 The Zoological Society of London.

  6. Nichelle Nichols, NASA Recruiter

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Actress Nichelle Nichols was born in Robbins, Illinois on December 29, 1936. She played Lieutenant Uhura the Communications Officer on the U.S.S. Enterprise in the original series, Star Trek. Nichols stayed with the show and has appeared in six Star Trek movies. Her portrayal of Uhura on Star Trek marked one of the first non-stereotypical roles assigned to an African-American actress. She also provided the voice for Lt. Uhura on the Star Trek animated series in 1974-75. Before joining the crew on Star Trek, she sang and danced with Duke Ellington's band. Nichols was always interested in space travel. She flew aboard the C-141 Astronomy Observatory, which analyzed the atmospheres of Mars and Saturn on an eight hour, high altitude mission. From the late 1970's until the late 1980's, NASA employed Nichelle Nichols to recruit new astronaut candidates. Many of her new recruits were women or members of racial and ethnic minorities, including Guion Bluford (the first African-American astronaut), Sally Ride (the first female American astronaut), Judith Resnik (one of the original set of female astronauts, who perished during the launch of the Challenger on January 28, 1986), and Ronald McNair (the second African-American astronaut, and another victim of the Challenger accident). Currently Nichelle Nichols is actively involved in movies and special appearances. She is also a spokesperson for her favorite charity, 'The Kwanzaa Foundation.'

  7. Avoidance of aluminum by rainbow trout

    SciTech Connect

    Exley, C.

    2000-04-01

    Aluminum is the principal toxicant in fish in acid waters. The ability to avoid Al, particularly at low concentrations, would confer a considerable ecological advantage, but previous research into avoidance of Al has produced mixed results. The author used a cylindrical perspex tank, 150 cm in length, to study avoidance of Al by rainbow trout fry. The fish avoided Al, and their response was dependent on pH. Avoidance that was demonstrated at pHs of 5.00, 5.50, 5.50, and 5.75 was abolished at a pH of 6.00. Fry avoided very low Al concentrations being sensitive to [Al] > 1.00 {micro}mol L{sup {minus}1} at a pH of 5.00. This unequivocal demonstration of avoidance by rainbow trout fry of Al may have important implications for the ecology of indigenous fish populations in surface waters impacted by acidic deposition.

  8. Trout hepatoma--a preliminary report

    USGS Publications Warehouse

    Rucker, R.R.; Yasutake, W.T.; Wolf, H.

    1961-01-01

    Fish pathology and its role in fish culture were brought into prominence in the spring of 1960 by the disclosure of a high incidence of hepatomas in hatchery-reared rainbow trout. The current problem came to light as the result of a routine inspection of live trout shipments at a California border fish-disease checking station. This service is performed by personnel of the California Department of Fish and Game to preclude the introduction or further spread of communicable fish diseases into California watersheds. Collaborative studies which followed revealed the nationwide distribution of the disease. This unusual disease soon attracted the attention of the Bureau of Sport Fisheries and Wildlife, the Food and Drug Administration, Public Health Service, and several western State health and conservation agencies.

  9. Massive obstructive urolithiasis in a bull used for artificial insemination.

    PubMed

    Ogaa, J S; Agumbah, G J; Patel, J H; Kiere, S; Mwangi, J L

    A seven-year-old Jersey bull used for artificial insemination showed clinical signs of obstructive urolithiasis. This was confirmed by catheterisation and subsequent urethrotomy over the site of obstruction distal to the sigmoid flexure. Although urine flow was elicited after removal of the calculi, this was only temporary and the animal had to be killed 24 hours later. On post mortem examination about 2 kg of round, smooth, pearl-like calculi were found in the urinary bladder and the urethra of the sigmoid flexure was studded with similar calculi. It was concluded that urethrotomy at the sigmoid flexure or penectomy post scrotally would not have alleviated this condition.

  10. eHealth recruitment challenges.

    PubMed

    Thompson, Debbe; Canada, Ashanti; Bhatt, Riddhi; Davis, Jennifer; Plesko, Lisa; Baranowski, Tom; Cullen, Karen; Zakeri, Issa

    2006-11-01

    Little is known about effective eHealth recruitment methods. This paper presents recruitment challenges associated with enrolling African-American girls aged 8-10 years in an eHealth obesity prevention program, their effect on the recruitment plan, and potential implications for eHealth research. Although the initial recruitment strategy was literature-informed, it failed to enroll the desired number of girls within a reasonable time period. Therefore, the recruitment strategy was reformulated to incorporate principles of social marketing and traditional marketing techniques. The resulting plan included both targeted, highly specific strategies (e.g., selected churches), and more broad-based approaches (e.g., media exposure, mass mailings, radio advertisements). The revised plan enabled recruitment goals to be attained. Media appeared to be particularly effective at reaching the intended audience. Future research should identify the most effective recruitment strategies for reaching potential eHealth audiences.

  11. Factors influencing brown trout reproductive success in Ozark tailwater rivers

    USGS Publications Warehouse

    Pender, D.R.; Kwak, T.J.

    2002-01-01

    The reproductive success of brown trout Salmo trutta in White River, Arkansas, tailwater reaches is highly variable, resulting in the need for supplemental stocking. A better understanding of the physical and biotic factors affecting reproduction and survival would enhance the contribution of wild fish. We compared fecundity, reproductive chronology, physical habitat, water quality, trout density, food availability, diet, predation, and competitive interactions among four tailwater reaches to identify factors influencing brown trout reproductive success. The fecundity and condition factor of prespawning brown trout were significantly lower at Beaver Tailwater, a reach known for reproductive failure, than at other sites, among which no differences were found. Brown trout spawning was observed from 11 October to 23 November 1996, and juvenile emergence began on 28 February 1997. Significant among-site differences were detected for spawning and juvenile microhabitat variables, but the variables fell within or near suitable or optimal ranges reported in the literature for this species. Age-0 brown trout density differed significantly among sites, but growth and condition did not. Predation by Ozark sculpin Cottus hypselurus on trout eggs or age-0 trout of any species was not observed among the 418 stomachs examined. Ozark sculpin density and diet overlap with age-0 brown trout were highest and invertebrate food availability and water fertility were lowest at Beaver Tailwater relative to the other reaches. Our findings indicate that differences in trophic conditions occur among tailwater reaches, and a lower system productive capacity was identified at Beaver Tailwater. We suggest that management efforts include refining the multispecies trout stocking regime to improve production efficiency, enhancing flow regulation, and increasing habitat complexity to increase invertebrate and fish productivity. Such efforts may lead to improved natural reproduction and the

  12. Tetrazolium Oxidase Polymorphism in Rainbow Trout

    PubMed Central

    Cederbaum, Stephen D.; Yoshida, Akira

    1972-01-01

    Tetrazolium oxidase from the blood and liver of rainbow trout was found to be genetically polymorphic. The inheritance pattern of the liver enzyme was compatible only with a one locus-two allele hypothesis. The enzymes in the blood while having an electrophoretically identical polymorphism could differ genotypically from that of the liver in a given fish. The significance of these findings to the understanding of the evolution of the salmonid genome is discussed. PMID:4675090

  13. Evaluation of bison (Bison bison) semen from Yellowstone National Park, Montana, USA, bulls for Brucella abortus shedding.

    PubMed

    Frey, Rebecca K; Clarke, P Ryan; McCollum, Matt P; Nol, Pauline; Johnson, Kammy R; Thompson, Brent D; Ramsey, Jennifer M; Anderson, Neil J; Rhyan, Jack C

    2013-07-01

    To determine if bison (Bison bison) bulls from Yellowstone National Park (YNP), Montana, USA, shed an infective dose of Brucella abortus in semen, 50 YNP bulls were captured on public lands in Montana during the winter and early spring (April-May) of 2010 and 2011. The bulls were immobilized, and blood and semen samples were collected for serology and Brucella culture. Thirty-five bulls (70%) were antibody-positive, and B. abortus was cultured from semen in three (9%) of the 35 antibody-positive or suspect bulls, though not at concentrations considered an infective dose. Eight bulls (six antibody-positive, two negative) had palpable lesions of the testes, epididymides, or seminal vesicles consistent with B. abortus infection. Breeding soundness exams and semen analysis suggested that antibody-positive bulls were more likely to have nonviable ejaculate (8/35; 23%) than bulls without detectable antibody (2/15; 13%).

  14. Brook trout passage performance through culverts

    USGS Publications Warehouse

    Goerig, Elsa; Castro-Santos, Theodore R.; Bergeron, Normand

    2016-01-01

    Culverts can restrict access to habitat for stream-dwelling fishes. We used passive integrated transponder telemetry to quantify passage performance of >1000 wild brook trout (Salvelinus fontinalis) attempting to pass 13 culverts in Quebec under a range of hydraulic and environmental conditions. Several variables influenced passage success, including complex interactions between physiology and behavior, hydraulics, and structural characteristics. The probability of successful passage was greater through corrugated metal culverts than through smooth ones, particularly among smaller fish. Trout were also more likely to pass at warmer temperatures, but this effect diminished above 15 °C. Passage was impeded at higher flows, through culverts with steep slopes, and those with deep downstream pools. This study provides insight on factors influencing brook trout capacity to pass culverts as well as a model to estimate passage success under various conditions, with an improved resolution and accuracy over existing approaches. It also presents methods that could be used to investigate passage success of other species, with implications for connectivity of the riverscape.

  15. Associations between endotoxin-induced metabolic changes and temperament in Brahman bulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influence of temperament on the alteration of metabolic parameters in response to a lipopolysaccharide (LPS) challenge was investigated. Brahman bulls were selected for this study based on temperament score. Bulls were fitted with indwelling jugular catheters for serial sampling to evaluate peri...

  16. Influence of temperament and transportation on physiological and endocrinological parameters in bulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study measured physiological, immunological, and endocrinological responses to transportation. Based on temperament score (TS), the 7 most calm (TS = 0.84 +/- 0.03) and 8 most temperamental (TS = 3.37 +/- 0.18) Brahman bulls were selected from our research herd. Prior to transportation, bulls w...

  17. 7 CFR 59.102 - Mandatory daily reporting for cows and bulls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Mandatory daily reporting for cows and bulls. 59.102... (CONTINUED) LIVESTOCK MANDATORY REPORTING Cattle Reporting § 59.102 Mandatory daily reporting for cows and bulls. (a) In General. The corporate officers or officially designated representatives of each cow...

  18. Use of NMR and NMR Prediction Software to Identify Components in Red Bull Energy Drinks

    ERIC Educational Resources Information Center

    Simpson, Andre J.; Shirzadi, Azadeh; Burrow, Timothy E.; Dicks, Andrew P.; Lefebvre, Brent; Corrin, Tricia

    2009-01-01

    A laboratory experiment designed as part of an upper-level undergraduate analytical chemistry course is described. Students investigate two popular soft drinks (Red Bull Energy Drink and sugar-free Red Bull Energy Drink) by NMR spectroscopy. With assistance of modern NMR prediction software they identify and quantify major components in each…

  19. 75 FR 17106 - Safety Zone; Red Bull Air Race, Detroit River, Detroit, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-05

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Red Bull Air Race, Detroit River, Detroit... vessels from portions of the Detroit River during the Red Bull Air Race. This temporary safety zone is... on the water could easily result in serious injuries or fatalities. Establishing a safety zone...

  20. "As if Reviewing His Life": Bull Lodge's Narrative and the Mediation of Self-Representation

    ERIC Educational Resources Information Center

    Gone, Joseph P.

    2006-01-01

    In 1980, on behalf of the Gros Ventre people, George P. Horse Capture published "The Seven Visions of Bull Lodge, as Told by His Daughter, Garter Snake." "The Seven Visions" describes a lifetime of personal encounters with Powerful other-than-human Persons by the noted Gros Ventre warrior and ritual leader, Bull Lodge (ca.…

  1. Foucault and Colonial Strategy in Douglas C. Jones' "Arrest Sitting Bull"

    ERIC Educational Resources Information Center

    Murphy, Peter G.

    2004-01-01

    "Arrest Sitting Bull," a novel written by Douglas C. Jones that relates the personal stories of individuals involved in the military and the political domination of the Sioux Indian during the period leading to the Sitting Bull killing is described. The incessant quest to establish and maintain control and the integral roles played by fear and…

  2. Effect of supplemental trace mineral level and form on peripubertal bulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives were to determine if different supplemental trace mineral levels and /or forms (sulfate and metal amino acid complexes) influence age at puberty, semen quality, endocrine status and scrotal circumference in peripubertal bulls. Fifty crossbred, peripubertal bulls were blocked by age (...

  3. Reproductive characteristics of grass-fed, luteinizing hormone-releasing hormone-immunocastrated Bos indicus bulls.

    PubMed

    Hernandez, J A; Zanella, E L; Bogden, R; de Avila, D M; Gaskins, C T; Reeves, J J

    2005-12-01

    Two field trials were conducted in Brazil to evaluate LHRH immunocastration of Bos indicus bulls (d 0 = 2 yr of age). In Study I, 72 bulls were assigned randomly to one of three treatment groups: LHRH0-immunized, castrated, and intact. Immunized animals (n = 25) received a primary and two booster injections of ovalbumin-LHRH-7 and thioredoxin-LHRH-7 fusion proteins on d 0, 141, and 287. Twenty-three bulls were surgically castrated on d 141, and 24 served as intact controls. All animals were slaughtered on d 385, at approximately 3 yr of age. In Study II, 216 bulls were assigned randomly to the same three treatments as in Study I; however, because of a drought in the area, bulls were kept on pasture an additional year, and a fourth treatment was added, in which one-half the LHRH-immunized bulls received an additional booster on d 639 (fourth immunization). All animals in Study II were slaughtered on d 741 (4 yr of age). Luteinizing hormone-releasing hormone antibodies increased following each immunization for immunized bulls, but they were not detectable in castrate or intact animals in either study. Consequently, scrotal circumference was suppressed in immunized bulls compared with intact controls in both studies. By d 287, serum concentrations of testosterone in LHRH-immunized bulls were decreased compared with intact controls (P < 0.01). In both studies, testes and epididymal weights at slaughter were greater (P < 0.01) for intact (500 +/- 17 and 60 +/- 2 g, respectively) than for immunized bulls (173 +/- 22 and 26 +/- 2 g, respectively) and fourth immunization bulls (78 +/- 23 and 20 +/- 2 g, respectively; Study II). At the end of each study, BW was greater (P < 0.01) for intact bulls than for castrated and LHRH-immunized animals. In these two studies, the efficacy of the LHRH fusion proteins to induce an effect similar to that of surgical castration was considered 92 and 93%, respectively. These data support the concept that immunocastration of bulls at 2 yr of

  4. The effects of varied densities on the growth and emigration of adult cutthroat trout and brook trout in fenced stream enclosures

    USGS Publications Warehouse

    Buys, D.J.; Hilderbrand, R.H.; Kershner, J.L.

    2009-01-01

    We evaluated the effects of various density treatments on adult fish growth and emigration rates between Bonneville cutthroat trout Oncorhynchus clarki utah and brook trout Salvelinus fontinalis in stream enclosures in Beaver Creek, Idaho, We used 3 density treatments (low, ambient, and high fish densities) to evaluate density-related effects and to ensure a response. Intraspecific ambient-density tests using cutthroat trout only were also performed. Results indicated an absence of cage effects in the stream enclosures and no differences in fish growth between ambient-density stream-enclosure fish and free-range fish. Brook trout outgrew and moved less than cutthroat trout in the stream enclosures, especially as density increased, In all 3 density treatments, brook trout gained more weight than cutthroat trout, with brook trout gaining weight in each density treatment and cutthroat trout losing weight at the highest density. At high densities, cutthroat trout attempted to emigrate more frequently than brook trout in sympatry and allopatry. We observed a negative correlation between growth and emigration for interspecific cutthroat trout, indicating a possible competitive response due to the presence of brook trout. We observed similar responses for weight and emigration in trials of allopatric cutthroat trout, indicating strong intraspecific effects as density increased. While cutthroat trout showed a response to experimental manipulation with brook trout at different densities, there has been long-term coexistence between these species in Beaver Creek, This system presents a unique opportunity to study the mechanisms that lead cutthroat trout to coexist with rather than be replaced by nonnative brook trout.

  5. Relationship between the nuclear morphology of the sperm of 10 bulls and their fertility.

    PubMed

    Vieytes, A L; Cisale, H O; Ferrari, M R

    2008-11-22

    The relationships between the fertility and nuclear morphology, chromatin maturity and chromatin condensation of the sperm of three bulls with a calving rate over a year of more than 65 per cent, four bulls with a calving rate between 65 per cent and 35 per cent, and three bulls with a calving rate of less than 35 per cent were studied. The sperm nuclei were stained with the Feulgen reaction, and chromatin condensation and maturation were evaluated in situ by staining with toluidine blue and acid aniline blue. Nuclear chromatin decondensation was induced with dithiothreitol; this showed that in the bulls with low fertility, more than 35 per cent of nuclei were decondensed, and that one of them had the lowest percentage of normal nuclei (64.9 per cent) and stronger positive reactions to the acid aniline blue and toluidine blue stains than the other bulls.

  6. Status of the rainbow trout genome reference sequence assembly

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rainbow trout (Oncorhynchus mykiss) are the most cultivated cold water fish in the U.S. In addition to interests associated with aquaculture and sport fisheries, the rainbow trout serves as a model research organism for studies related to carcinogenesis, toxicology, comparative immunology, disease ...

  7. Communications: Blood chemistry of laboratory-reared Golden trout

    USGS Publications Warehouse

    Hunn, Joseph B.; Wiedmeyer, Ray H.; Greer, Ivan E.; Grady, Andrew W.

    1992-01-01

    Golden trout Oncorhynchus aguabonita obtained from a wild stock as fertilized eggs were reared in the laboratory for 21 months. The laboratory-reared golden trout in our study reached sexual maturity earlier and grew more rapidly than wild golden trout do (according to the scientific literature). Male fish averaged 35.6 cm in total length and 426 g in weight, and females averaged 36.2 cm and 487 g. All golden trout were sexually mature when used for hematological analysis. The hematological profile (hematocrit, red blood cells, white blood cells, and thrombocytes) of golden trout was similar to that reported elsewhere for other trout species. Male and female golden trout did not have significantly different thrombocyte counts; however, the immobilization treatment used on the fish (anesthesia versus a blow to the head) resulted in significant treatment differences in thrombocyte numbers and interaction effect of sex in treatment for hematocrits. Gravid female golden trout had significantly higher plasma protein and calcium levels than did males. The ionic compositions of plasma (sodium, potassium, calcium, magnesium, copper, zinc, iron, and chloride) and gallbladder bile (calcium and chloride) were similar to those reported for other salmonids.

  8. Progress of the rainbow trout reference genome assembly project

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rainbow trout are the most widely cultivated cold freshwater fish in the world and an important model species for many research areas. Despite this importance, the complex nature of the rainbow trout genome (pseudotetraploid and high repeat content) has hindered the production of a high-quality refe...

  9. Sperm protamine-status correlates to the fertility of breeding bulls.

    PubMed

    Dogan, Sule; Vargovic, Peter; Oliveira, Rodrigo; Belser, Lauren E; Kaya, Abdullah; Moura, Arlindo; Sutovsky, Peter; Parrish, John; Topper, Einko; Memili, Erdoğan

    2015-04-01

    During fertilization, spermatozoa make essential contributions to embryo development by providing oocyte activating factors, centrosomal components, and paternal chromosomes. Protamines are essential for proper packaging of sperm DNA; however, in contrast to the studies of oocyte-related female infertility, the influence of sperm chromatin structure on male infertility has not been evaluated extensively. The objective of this study was to determine the sperm chromatin content of bull spermatozoa by evaluating DNA fragmentation, chromatin maturity/protamination, PRM1 protein status, and nuclear shape in spermatozoa from bulls with different fertility. Relationships between protamine 1 (PRM1) and the chromatin integrity were ascertained in spermatozoa from Holstein bulls with varied (high vs. low) but acceptable fertility. Sperm DNA fragmentation and chromatin maturity (protamination) were tested using Halomax assay and toluidine blue staining, respectively. The PRM1 content was assayed using Western blotting and in-gel densitometry, flow cytometry, and immunocytochemistry. Fragmentation of DNA was increased and chromatin maturity significantly reduced in spermatozoa from low-fertility bulls compared to those from high-fertility bulls. Field fertility scores of the bulls were negatively correlated with the percentage of spermatozoa displaying reduced protamination and fragmented DNA using toluidine blue and Halomax, respectively. Bull fertility was also positively correlated with PRM1 content by Western blotting and flow cytometry. However, detection of PRM1 content by Western blotting alone was not predictive of bull fertility. In immunocytochemistry, abnormal spermatozoa showed either a lack of PRM1 or scattered localization in the apical/acrosomal region of the nuclei. The nuclear shape was distorted in spermatozoa from low-fertility bulls. In conclusion, we showed that inadequate amount and localization of PRM1 were associated with defects in sperm chromatin

  10. Ontogenetic taurine biosynthesis ability in rainbow trout (Oncorhynchus mykiss).

    PubMed

    Wang, Xuan; He, Gen; Mai, Kangsen; Xu, Wei; Zhou, Huihui

    2015-07-01

    Taurine (2-aminoethane sulfonic acid) plays important roles in multiple physiological processes including osmoregulation, bile salt conjugation and membrane protection. It is known that taurine biosynthesis varies in different fish species. However, its ontogenetic regulation has not been clear. In the present study, we found that the hepatic concentrations of taurine increased marginally with rainbow trout growth. The mRNA expression, protein levels and enzyme activities of key enzymes involved in taurine biosynthesis, cysteine dioxygenase (CDO) and cysteine sulfinate decarboxylase (CSD), were analyzed. Our results showed that the mRNA levels and protein abundances of CSD increased dramatically with the development of rainbow trout stages while the enzyme activities showed a slight improvement. However, the expression and activities of CDO decreased with rainbow trout growth. These results provide valuable information on defining the exact supplementation of taurine in diets for different stages of rainbow trout and give new insights into elucidating the regulation of taurine metabolism in rainbow trout.

  11. Clinostomum marginatum in steelhead trout (Salmo gairdneri) and cutthroat trout (Salmo clarki) in a western Washington lake

    USGS Publications Warehouse

    Uzmann, J.R.; Douglas, J.

    1966-01-01

    Clinostomum marginatum (Trematoda: Clinostomatidae), the yellow grub parasite, was recorded in epizootic proportions from Lynch Lake, King County, Washington, in 1961 and 1962. The parasite larvae occurred principally in steelhead trout (Salmo gairdneri); cutthroat trout (S. clarki) were infected to a relatively minor degree. Fish and snail host populations were destroyed by rotenone and copper sulfate treatments.

  12. Effects of water temperature and fish size on predation vulnerability of juvenile humpback chub to rainbow trout and brown trout

    USGS Publications Warehouse

    Ward, David L.; Morton-Starner, Rylan

    2015-01-01

    Predation on juvenile native fish by introduced Rainbow Trout and Brown Trout is considered a significant threat to the persistence of endangered Humpback Chub Gila cypha in the Colorado River in the Grand Canyon. Diet studies of Rainbow Trout and Brown Trout in Glen and Grand canyons indicate that these species do eat native fish, but impacts are difficult to assess because predation vulnerability is highly variable, depending on prey size, predator size, and the water temperatures under which the predation interactions take place. We conducted laboratory experiments to evaluate how short-term predation vulnerability of juvenile native fish changes in response to fish size and water temperature using captivity-reared Humpback Chub, Bonytail, and Roundtail Chub. Juvenile chub 45–90 mm total length (TL) were exposed to adult Rainbow and Brown trouts at 10, 15, and 20°C to measure predation vulnerability as a function of water temperature and fish size. A 1°C increase in water temperature decreased short-term predation vulnerability of Humpback Chub to Rainbow Trout by about 5%, although the relationship is not linear. Brown Trout were highly piscivorous in the laboratory at any size > 220 mm TL and at all water temperatures we tested. Understanding the effects of predation by trout on endangered Humpback Chub is critical in evaluating management options aimed at preserving native fishes in Grand Canyon National Park.

  13. Metals-contaminated benthic invertebrates in the Clark Fork River, Montana: Effects on age-0 brown trout and rainbow trout

    USGS Publications Warehouse

    Woodward, Daniel F.; Farag, Aïda M.; Bergman, Harold L.; Delonay, Aaron J.; Little, Edward E.; Smiths, Charlie E.; Barrows, Frederic T.

    1995-01-01

    Benthic organisms in the upper Clark Fork River have recently been implicated as a dietary source of metals that may be a chronic problem for young-of-the-year rainbow trout (Oncorhynchus mykiss). In this present study, early life stage brown trout (Salmo trutta) and rainbow trout were exposed for 88 d to simulated Clark Fork River water and a diet of benthic invertebrates collected from the river. These exposures resulted in reduced growth and elevated levels of metals in the whole body of both species. Concentrations of As, Cd, Cu, and Pb increased in whole brown trout; in rainbow trout, As and Cd increased in whole fish, and As also increased in liver. Brown trout on the metals-contaminated diets exhibited constipation, gut impaction, increased cell membrane damage (lipid peroxidation), decreased digestive enzyme production (zymogen), and a sloughing of intestinal mucosal epithelial cells. Rainbow trout fed the contaminated diets exhibited constipation and reduced feeding activity. We believe that the reduced standing crop of trout in the Clark Fork River results partly from chronic effects of metals contamination in benthic invertebrates that are important as food for young-of-the-year fish.

  14. Growth rate differences between resident native brook trout and non-native brown trout

    USGS Publications Warehouse

    Carlson, S.M.; Hendry, A.P.; Letcher, B.H.

    2007-01-01

    Between species and across season variation in growth was examined by tagging and recapturing individual brook trout Salvelinus fontinalis and brown trout Salmo trutta across seasons in a small stream (West Brook, Massachusetts, U.S.A.). Detailed information on body size and growth are presented to (1) test whether the two species differed in growth within seasons and (2) characterize the seasonal growth patterns for two age classes of each species. Growth differed between species in nearly half of the season- and age-specific comparisons. When growth differed, non-native brown trout grew faster than native brook trout in all but one comparison. Moreover, species differences were most pronounced when overall growth was high during the spring and early summer. These growth differences resulted in size asymmetries that were sustained over the duration of the study. A literature survey also indicated that non-native salmonids typically grow faster than native salmonids when the two occur in sympatry. Taken together, these results suggest that differences in growth are not uncommon for coexisting native and non-native salmonids. ?? 2007 The Authors.

  15. Grizzly bear predation links the loss of native trout to the demography of migratory elk in Yellowstone

    USGS Publications Warehouse

    Middleton, Arthur D.; Morrison, Thomas A.; Fortin, Jennifer K.; Robbins, Charles T.; Proffitt, Kelly M.; White, P.J.; McWhirter, Douglas E.; Koel, Todd M.; Brimeyer, Douglas G.; Fairbanks, W. Sue; Kauffman, Matthew J.

    2013-01-01

    The loss of aquatic subsidies such as spawning salmonids is known to threaten a number of terrestrial predators, but the effects on alternative prey species are poorly understood. At the heart of the Greater Yellowstone ecosystem, an invasion of lake trout has driven a dramatic decline of native cutthroat trout that migrate up the shallow tributaries of Yellowstone Lake to spawn each spring. We explore whether this decline has amplified the effect of a generalist consumer, the grizzly bear, on populations of migratory elk that summer inside Yellowstone National Park (YNP). Recent studies of bear diets and elk populations indicate that the decline in cutthroat trout has contributed to increased predation by grizzly bears on the calves of migratory elk. Additionally, a demographic model that incorporates the increase in predation suggests that the magnitude of this diet shift has been sufficient to reduce elk calf recruitment (4–16%) and population growth (2–11%). The disruption of this aquatic–terrestrial linkage could permanently alter native species interactions in YNP. Although many recent ecological changes in YNP have been attributed to the recovery of large carnivores—particularly wolves—our work highlights a growing role of human impacts on the foraging behaviour of grizzly bears.

  16. Grizzly bear predation links the loss of native trout to the demography of migratory elk in Yellowstone.

    PubMed

    Middleton, Arthur D; Morrison, Thomas A; Fortin, Jennifer K; Robbins, Charles T; Proffitt, Kelly M; White, P J; McWhirter, Douglas E; Koel, Todd M; Brimeyer, Douglas G; Fairbanks, W Sue; Kauffman, Matthew J

    2013-07-07

    The loss of aquatic subsidies such as spawning salmonids is known to threaten a number of terrestrial predators, but the effects on alternative prey species are poorly understood. At the heart of the Greater Yellowstone ecosystem, an invasion of lake trout has driven a dramatic decline of native cutthroat trout that migrate up the shallow tributaries of Yellowstone Lake to spawn each spring. We explore whether this decline has amplified the effect of a generalist consumer, the grizzly bear, on populations of migratory elk that summer inside Yellowstone National Park (YNP). Recent studies of bear diets and elk populations indicate that the decline in cutthroat trout has contributed to increased predation by grizzly bears on the calves of migratory elk. Additionally, a demographic model that incorporates the increase in predation suggests that the magnitude of this diet shift has been sufficient to reduce elk calf recruitment (4-16%) and population growth (2-11%). The disruption of this aquatic-terrestrial linkage could permanently alter native species interactions in YNP. Although many recent ecological changes in YNP have been attributed to the recovery of large carnivores--particularly wolves--our work highlights a growing role of human impacts on the foraging behaviour of grizzly bears.

  17. Electroejaculation increased vocalization and plasma concentrations of cortisol and progesterone, but not substance P, in beef bulls.

    PubMed

    Whitlock, B K; Coffman, E A; Coetzee, J F; Daniel, J A

    2012-09-01

    Electroejaculation is a reliable method of obtaining a semen sample for a bull breeding soundness examination, but is sometimes regarded as painful. Substance P is a neuropeptide involved in the integration of pain, stress, and anxiety. We hypothesized that substance P is a measure of pain in bulls following electroejaculation. The specific objective was to compare vocalization and plasma concentrations of cortisol, progesterone, and substance P immunoreactivity in bulls following electroejaculation. Nine Angus bulls (501.9 ± 14.3 kg) were used. Blood samples were collected at -60, -30, 0, 2, 10, 20, 30, 45, 60, 75, 90, 120 min relative to treatment. At Time 0, bulls were subject to electroejaculation, rectal probe insertion without electroejaculation, or no manipulation. Treatments were administered contemporaneously to three bulls. Treatments were repeated weekly until each bull had received each treatment in a 3 × 3 Latin square design. More bulls (P = 0.0147) in the electroejaculation group vocalized (5 of 9 bulls; 55.6%) when compared to controls (0 of 9 bulls; 0%). Mean plasma cortisol and progesterone concentration following electroejaculation in bulls were higher (P < 0.05) than concentrations in probed and control bulls through the 45 min sample. However, mean plasma substance P concentration following electroejaculation in bulls (77.2 ± 17.2 pg/mL) was not different (P = 0.6264) from probed (79.1 ± 17.2 pg/mL) or control bulls (93.4 ± 17.2 pg/mL). A significant increase in vocalization and plasma cortisol and progesterone concentrations in bulls following electroejaculation was likely owing to acute stress. However, the lack of a difference in plasma concentrations of substance P after electroejaculation was interpreted as a lack of pain associated with nociception.

  18. Introduction and summary: Chlorinated hydrocarbons as a factor in the reproduction and survival of lake trout (Salvelinus namaycush) in Lake Michigan

    USGS Publications Warehouse

    Willford, Wayne A.; Bergstedt, Roger A.; Berlin, William H.; Foster, Neal R.; Hesselberg, Robert J.; Mac, Michael J.; Passino, Dora R. May; Reinert, Robert E.; Rottiers, Donald V.

    1981-01-01

    . Although several factors have undoubtedly contributed to the lack of recruitment of naturally produced lake trout in Lake Michigan, the levels of PCB's and DDE present during the early to mid 1970's were sufficient to significantly reduce survival of any fry produced in the lake and thereby impede restoration of the lake trout population to self-sustainability. The added exposure of the fry to other toxic substances known to be present in the lake could have further reduced survival.

  19. Bull Fertility and Its Relation with Density Gradient Selected Sperm

    PubMed Central

    Allouche, Lynda; Madani, Toufik; Mechmeche, Mohamed; Clement, Laetitia; Bouchemal, Allaoua

    2017-01-01

    Background Sperm selection method is usually used to collect these cells for in vitro-assisted reproduction. Few studies reported the relationship of in vivo fertility and semen parameters after sperm selection; hence, the present study attempted to assess different semen parameters after post-thaw or sperm selection, using density gradient separation BoviPure®, to predict in vivo fertility. Materials and Methods In this experimental study, frozen semen quality of four Montbeliarde bulls were assessed after post-thaw (PT) or after sperm selection (SSp), using density gradient separation BoviPure®, to predict the fertility rate in vivo. In addition to PT or SSp, semen was examined for concentration, motility, morphology abnormalities, viability, acrosome and plasma membrane integrities. Fertility was measured as non-return rates within 56 days after the first insemination (NRR) or as corrected NRR, expressed as CNRR, to the factors influencing fertility using linear mixed model. Non-parametric Kruskal-Wallis test was performed to compare semen parameter variables. Fertility rates were compared using Chi-square test. Pearson correlation analysis was used to test the relationship between CNRR and semen parameters. Data was analysed using SPSS package program, version 21.0. Results Most of the examined bulls exhibited a high fertility rate (3/4 bulls, 62.1- 81.8% for NRR or 67.2-98.5% for CNRR). Fertility rate, expressed as CNRR, was significantly related to semen parameters after SSp, but not after PT. Thus, CNRR was increased with decrease of total motility, progressive spermatozoa and abaxial implantation frequencies after SSp (r=-0.999, P=0.001; r=-0.990, P=0.010; r=-0.988, P= 0.012, respectively); while, CNRR was decreased with decrease of SSp immotile spermatozoa (r=+0.995, P=0.005), underlying that maximal limit of determined immotile spermatozoa is 47%. Conclusion High frequencies of total and progressive motility spermatozoa, and abaxial implantation in

  20. Patterns of natural mortality in stream-living brown trout (Salmo trutta)

    USGS Publications Warehouse

    Lobon-Cervia, J.; Budy, P.; Mortensen, E.

    2012-01-01

    We tested the hypothesis that lifetime mortality patterns and their corresponding rates and causal factors differ among populations of stream-living salmonids. To this end, we examined the lifetime mortality patterns of several successive cohorts of two stream-living brown trout (Salmo trutta) populations in Spain and Denmark. In the southern population, we observed a consistent two-phase pattern, in which mortality was negligible during the first half of the lifetime and severe during the rest of the lifetime. In contrast, the northern population demonstrated a three-phase pattern with an earlier phase varying from negligible to severe, followed by a second stage of weak mortality, and lastly by a third life stage of severe mortality. Despite substantial differences in the mortality patterns between the two populations, the combined effect of recruitment (as a proxy of the density-dependent processes occurring during the lifetime) and mean body mass (as a proxy of growth experienced by individuals in a given cohort) explained c. 89% of the total lifetime mortality rates across cohorts and populations. A comparison with other published data on populations of stream-living brown trout within its native range highlighted lifetime mortality patterns of one, two, three and four phases, but also suggested that common patterns may occur in populations that experience similar individual growth and population density. ?? 2011 Blackwell Publishing Ltd.

  1. Rapid natural selection for resistance to an introduced parasite of rainbow trout

    PubMed Central

    Miller, Mark P; Vincent, E Richard

    2008-01-01

    Introduced species and infectious diseases both independently pose challenges for the preservation of existing biodiversity. However, native species or disease hosts are by no means ‘unarmed’ when faced with novel environmental challenges, provided that adequate adaptive genetic variation exists to mount effective evolutionary responses. In this study, we examined the consequences of the recently introduced parasite and causative agent of whirling disease (Myxobolus cerebralis) in a wild rainbow trout (Oncorhynchus mykiss) population from Harrison Lake, Montana (USA). Consistent with the parasite’s age-specific effects, juvenile rainbow trout recruitment into Harrison Lake was substantially reduced following parasite detection in 1995. However, experimental data suggest that natural selection has rapidly reduced whirling disease susceptibility within the population over time. The rapid observed temporal change in resistance patterns argues that the standing genetic variation for parasite resistance facilitated this process. Our findings ultimately underscore the importance of preserving genetic diversity to ensure that species of economic importance or of conservation concern have maximal chances for persistence in future changing environments. PMID:25567635

  2. Rapid natural selection for resistance to an introduced parasite of rainbow trout.

    PubMed

    Miller, Mark P; Vincent, E Richard

    2008-05-01

    Introduced species and infectious diseases both independently pose challenges for the preservation of existing biodiversity. However, native species or disease hosts are by no means 'unarmed' when faced with novel environmental challenges, provided that adequate adaptive genetic variation exists to mount effective evolutionary responses. In this study, we examined the consequences of the recently introduced parasite and causative agent of whirling disease (Myxobolus cerebralis) in a wild rainbow trout (Oncorhynchus mykiss) population from Harrison Lake, Montana (USA). Consistent with the parasite's age-specific effects, juvenile rainbow trout recruitment into Harrison Lake was substantially reduced following parasite detection in 1995. However, experimental data suggest that natural selection has rapidly reduced whirling disease susceptibility within the population over time. The rapid observed temporal change in resistance patterns argues that the standing genetic variation for parasite resistance facilitated this process. Our findings ultimately underscore the importance of preserving genetic diversity to ensure that species of economic importance or of conservation concern have maximal chances for persistence in future changing environments.

  3. Inbreeding depression on semen quality in Austrian dual-purpose simmental bulls.

    PubMed

    Maximini, L; Fuerst-Waltl, B; Gredler, B; Baumung, R

    2011-02-01

    Using pedigree data, the inbreeding coefficients of 715 Austrian dual-purpose Simmental (Fleckvieh) bulls stationed in two artificial insemination (AI) centres in Upper and Lower Austria were calculated and incorporated in statistical models for the analysis of semen quality. Five semen quality parameters (volume, concentration, motility, number of spermatozoa per ejaculate and percentage of viable spermatozoa) of approximately 30,000 ejaculates, used in two separate data sets, were investigated. The mixed model included the fixed effects age class of the bull, bull handler, semen collector, month and year of collection, number of collection per bull and day, time interval since last collection, the linear continuous effect of the inbreeding coefficient of the bull, interactions between age class and month, and age class and interval since last collection, respectively, as well as the random effect of the bull and the random residual effect. Non-linear effects of inbreeding were significant for motility only. Despite the quite low inbreeding coefficients (mean 1.3%), all semen quality traits showed inbreeding depression, in four of the five traits significantly in at least one of the data sets. The magnitude of inbreeding depression was small, which might partly be caused by the low inbreeding levels and a potential pre-selection of the bulls in the AI centres. However, monitoring of inbreeding depression on fertility traits is recommended to avoid unrecognized deterioration of such traits.

  4. Effects of diets containing gossypol on spermatogenic tissues of young bulls.

    PubMed

    Arshami, J; Ruttle, J L

    1988-09-01

    Eighteen yearling beef bulls were used in a study to determine the effects of diets containing gossypol on spermatogenic tissues, Sertoli cells and Leydig cells. Bulls were randomly assigned to one of three (n = 6) isonitrogenous diet groups formulated from alfalfa hay and corn (gossypol-free control), control plus whole cottonseed and cottonseed hulls, or control plus cottonseed meal and cottonseed hulls as sources of gossypol. Testicular tissues collected were examined histologically, and tissues from bulls fed gossypol-free diets were compared with those fed diets containing cottonseed products. Following a 2-mo period (P(1)) when bulls were fed diets containing gossypol, one-half of the bulls were placed on a gossypol-free diet for an additional 2 mo (P(2)) to determine if gossypol effects were reversible. At the end of P(1), bulls fed whole cottonseed and cottonseed meal had larger (P<0.01) lumens in their seminiferous tubules, decreased (P<0.001) wall thickness in their seminiferous tubules, and a reduced (P<0.0001) number of cell layers in their seminiferous tubles, when compared with bulls fed a gossypol-free diet. These histological changes indicate detrimental effects to the spermatogenic tissues and associated cells. Following the initial two months (P(1)) of receiving feed containing gossypol, herd mates that were fed a gossypol-free diet for 2 mo (P(2)) showed improvement in histological characteristics, indicating that gossypol-induced effects were partially reversible.

  5. Recruit and ADVANCE

    NASA Astrophysics Data System (ADS)

    Rosser, Sue V.

    2007-04-01

    Beginning in 2001, the National Science Foundation launched the ADVANCE Initiative, which has now awarded more than 70 million to some thirty institutions for transformations to advance women. Results of studies on how to attract and retain women students and faculty underpinned our ADVANCE Institutional Transformation grant funded by the NSF for 3.7 million for five years, beginning in 2001. As co-principal investigator on this grant, I insured that this research informed the five major threads of the grant: 1) Four termed ADVANCE professors to mentor junior women faculty in each college; 2) Collection of MIT-Report-like data indicators to assess whether advancement of women really occurs during and after the institutional transformation undertaken through ADVANCE; 3) Family-friendly policies and practices to stop the tenure clock and provide active service, modified duties, lactation stations and day care; 4) Mini-retreats to facilitate access for tenure-track women faculty to male decision-makers and administrators for informal conversations and discussion on topics important to women faculty; 5) Removal of subtle gender, racial, and other biases in promotion and tenure. The dynamic changes resulting from the grant in quality of mentoring, new understanding of promotion and tenure, numbers of women retained and given endowed chairs, and emergence of new family friendly policies gave me hope for genuine diversification of leadership in science and technology. As the grant funding ends, the absence of NSF prestige and monitoring, coupled with a change in academic leadership at the top, provide new challenges for institutionalization, recruitment, and advancement of women into leadership positions in science and engineering.

  6. NITRO MUSK ADDUCTS OF RAINBOW TROUT ...

    EPA Pesticide Factsheets

    Rainbow trout and other fish species can serve as 'sentinel' species for the assessment of ecological status and the presence of certain environmental contaminants. As such they act as bioindicators of exposure. Here we present seminal data regarding dose-response and toxicokinetics of trout hemoglobin adduct formation from exposure to nitro musks that are frequently used as fragrance ingredients in formulations of personal care products. Hemoglobin adducts serve as biomarkers of exposure of the sentinel species as we have shown in previous studies of hemoglobin adducts formed in trout and environmental carp exposed to musk xylene (MX) and musk ketone (MK). Gas chromatography-electron capture negative ion chemical ionization-mass spectrometry (GC-NICI-MS) employing selected ion monitoring is used to measure 4-amino-MX (4-AMX), 2-amino-MX (2-AMX), and 2-amino-MK (2-AMK) released by alkaline hydrolysis from the sulfinamide adducts of hemoglobin. Dose-response and toxicokinetics were investigated using this sensitive method for analysis of these metabolites. In the dose-response investigation, the concentrations of 4-AMX and 2-2AMX are observed to pass through a maximum at 0.10 mg/g. In the case of 2-AMK, the adduct concentration is almost the same at dosages in the range of 0.030 to 0.10 mg/g. For toxicokinetics, the concentration of the metabolites in the Hb reaches a maximum in the 3-day sample after administration of MX or MK. Further elimination of the metabo

  7. Diversity employment and recruitment sources

    SciTech Connect

    Not Available

    1994-08-01

    Effective human resources management has been identified as one of four critical success factors in the Department of Energy Strategic Plan. The Plan states relative to this factor: ``The Department seeks greater alignment of resources with agency priorities and increased diversification of the workforce, including gender, ethnicity, age, and skills. This diversification will bring new thinking and perspectives that heretofore have not had a voice in departmental decision-making.`` This Guide has been developed as a key tool to assist Department of Energy management and administrative staff in achieving Goal 2 of this critical success factor, which is to ``Ensure a diverse and talented workforce.`` There are numerous sources from which to recruit minorities, women and persons with disabilities. Applying creativity and proactive effort, using traditional and non-traditional approaches, and reaching out to various professional, academic and social communities will increase the reservoir of qualified candidates from which to make selections. In addition, outreach initiatives will undoubtedly yield further benefits such as a richer cultural understanding and diversity awareness. The resource listings presented in this Guide are offered to encourage active participation in the diversity recruitment process. This Guide contains resource listings by state for organizations in the following categories: (1) African American Recruitment Sources; (2) Asian American/Pacific Islander Recruitment Sources; (3) Hispanic Recruitment Sources; (4) Native American/Alaskan Native Recruitment Sources; (5) Persons with Disabilities Recruitment Sources; and (6) Women Recruitment Sources.

  8. Recruiting Migrant Students Reference Supplement.

    ERIC Educational Resources Information Center

    Johnson, Leon, Ed.

    This document reports on a study evaluating the practices of identification and recruitment of migrant students. Guided by a 14-state advisory council, data were collected by ethnographic research of practice in migrant recruitment and focus-group studies of migrant families. The document consists of five sections each written by a different…

  9. Nutrition Knowledge among Navy Recruits

    DTIC Science & Technology

    1987-03-27

    Nutrition Knovledge among Navy Recruits DTIC AELEOI7E flS SEP 2 8 1987 Terry L. Conway Linda K. Hervig D Ross R. Vickers, Jr. Health Psychology Department...5 Participants ............................................................. 5 Nutrition Knowledge Questionnaire...Students ............................... 6 Recruits’ Nutrition Knowledge .................................... ...... 8 Correlates of Nutrition Knowledge

  10. Three Keys to Better Recruiting

    ERIC Educational Resources Information Center

    Brazington, Alicia

    2012-01-01

    Recruitment is an expensive business: In 2010-2011, the median cost to recruit an undergraduate was $2,185 among private colleges and universities, according to Noel-Levitz, an enrollment management consultancy. In these tough fiscal times, admissions departments are under pressure to keep those costs down even as they pursue higher enrollment and…

  11. Changing Attitudes toward Teacher Recruitment.

    ERIC Educational Resources Information Center

    Maley, Donald

    The identification, encouragement, and recruitment of teachers is a professional responsibility that must be faced today. The field of industrial arts holds no external attractors; the job of teacher recruitment rests on the shoulders of teachers, supervisors, and teacher educators. Teachers have attitudes that fail to support any process that…

  12. Effect of Red Bull energy drink on cardiovascular and renal function.

    PubMed

    Ragsdale, Frances R; Gronli, Tyler D; Batool, Narjes; Haight, Nicole; Mehaffey, April; McMahon, Erin C; Nalli, Thomas W; Mannello, Carla M; Sell, Crystal J; McCann, Patrick J; Kastello, Gary M; Hooks, Tisha; Wilson, Ted

    2010-04-01

    Energy drink consumption has been anecdotally linked to the development of adverse cardiovascular effects in consumers, although clinical trials to support this link are lacking. The effects of Red Bull energy drink on cardiovascular and neurologic functions were examined in college-aged students enrolled at Winona State University. In a double-blind experiment where normal calorie and low calorie Red Bull were compared to normal and low calorie placebos, no changes in overall cardiovascular function nor blood glucose (mg/dL) were recorded in any participant (n = 68) throughout a 2-h test period. However, in the second experiment, nine male and twelve female participants subjected to a cold pressor test (CPT) before and after Red Bull consumption showed a significant increase in blood sugar levels pre- and post Red Bull consumption. There was a significant increase in diastolic blood pressure of the male volunteers immediately after submersion of the hand in the 5 degrees C water for the CPT. Under the influence of Red Bull, the increase in diastolic pressure for the male participants during the CPT was negated. There were no significant changes in the blood pressure of the female participants for the CPT with or without Red Bull. Finally, the CPT was used to evaluate pain threshold and pain tolerance before and after Red Bull consumption. Red Bull consumption was associated with a significant increase in pain tolerance in all participants. These findings suggest that Red Bull consumption ameliorates changes in blood pressure during stressful experiences and increases the participants' pain tolerance.

  13. An obscure disease of rainbow trout

    USGS Publications Warehouse

    Rucker, R.R.; Yasutake, W.T.; Wedemeyer, G.

    1970-01-01

    An annul mortality among Rainbow Trout (Salmo gairdneri) has plagued the Shelton Hatchery of the Washington State Department of Game for the last several years. No infectious agent could be isolated from the moribund fish, but histopathologica1 changes in the liver of 1-month-old fish suggested the presence of a toxic substance. Scoliosis in 3-month-old fish suggested a possible deficiency in vitamin C. With this background in mind, we designed studies to determine the nature and source of possible toxicants and the role of vitamin C deficiency in the etiology of this disease.

  14. The chemical disinfection of trout ponds

    USGS Publications Warehouse

    Fish, F.F.

    1933-01-01

    The need for knowledge concerning the prevention and control of fish diseases has never been greater than it is in this present era of economy when two fish must be raised in the same water which once supported but one. Fish pathologists have contributed a great deal to our knowledge of fish diseases, but there is still much to be learned, particularly concerning better methods of preventing and eliminating diseases among our trout. In this era of circular pools and raceways, our disease elimination is way back in the early days of standard troughs.

  15. Biotransformation of di(2-ethylhexyl)phthalate by rainbow trout

    SciTech Connect

    Barron, M.G.; Hayton, W.L.

    1995-05-01

    The biotransformation of di(2-ethylhexyl)phthalate (DEHP) was studied in rainbow trout (Oncorhynchus mykiss) following intravascular administration. Methyl-esterified metabolites were identified using rodent-derived standards and non-linear gradient elution HPLC; metabolites were confirmed by gas chromatography. Similarities between the biotransformation of DEHP by rainbow trout and mammalian species included (a) mono-ethylhexyl phthalate (MEHP) appeared to be the obligatory first step in DEHP metabolism; (b) the phthalate ring was not oxidized; (c) phthalic acid was a minor metabolite; and (d) several metabolites contained multiple oxidations of the 2-ethylhexyl moiety of MEHP. No metabolites unique to rainbow trout were identified. However, fewer oxidized metabolites were identified in rainbow trout than in mammalian species, possibly due to limited mitochondrial metabolism of MEHP in rainbow trout. The amount of biliary MEHP glucuronide after intravascular administration of DEHP was substantially less than reported in rainbow trout exposed to DEHP via the water. Results confirmed that DEHP metabolism in rainbow trout proceeds by initial rapid formation of MEHP, followed by excretion or extensive oxidation by microsomal P450.

  16. Population attributes of lake trout in Tennessee reservoirs

    USGS Publications Warehouse

    Russell, Drew; Bettoli, Phillip William

    2013-01-01

    We sampled stocked Salvelinus namaycush (Lake Trout) in Watauga Lake and South Holston Lake, TN using experimental gill nets in 2009-2010 to describe their growth, longevity, and condition. Annuli in sagittal otoliths formed once a year in early spring in both reservoirs. South Holston Lake (n = 99 Lake Trout) has been stocked since 2006, and the oldest fish was age 4. Watauga Lake has been stocked since the mid-1980s, and we collected 158 Lake Trout up to age 20. Annual mortality for age-3 and older fish in Watauga Lake was 24%. When compared to Lake Trout in northern lakes, Tennessee Lake Trout exhibited average to above-average growth and longevity. Condition of Lake Trout in both reservoirs varied seasonally and tended to be lowest in fall, but rebounded in winter and spring. Lake Trout in both reservoirs appeared to be spatially segregated from pelagic prey fishes during summer stratification, but growth rates and body condition were high enough to suggest that neither system was being overstocked.

  17. Reevaluation of lake trout and lake whitefish bioenergetics models

    USGS Publications Warehouse

    Madenjian, Charles P.; Pothoven, Steve A.; Kao, Yu-Chun

    2013-01-01

    Using a corrected algorithm for balancing the energy budget, we reevaluated the Wisconsin bioenergetics model for lake trout (Salvelinus namaycush) in the laboratory and for lake whitefish (Coregonus clupeaformis) in the laboratory and in the field. For lake trout, results showed that the bioenergetics model slightly overestimated food consumption by the lake trout when they were fed low and intermediate rations, whereas the model predicted food consumption by lake trout fed ad libitum without any detectable bias. The slight bias in model predictions for lake trout on restricted rations may have been an artifact of the feeding schedule for these fish, and we would therefore recommend application of the Wisconsin lake trout bioenergetics model to lake trout populations in the field without any revisions to the model. Use of the Wisconsin bioenergetics model for coregonids resulted in overestimation of food consumption by lake whitefish both in the laboratory and in the field by between 20 and 30%, on average. This overestimation of food consumption was most likely due to overestimation of respiration rate. We therefore adjusted the respiration component of the bioenergetics model to obtain a good fit to the observed consumption in our laboratory tanks. The adjusted model predicted the consumption in the laboratory and the field without any detectable bias. Until a detailed lake whitefish respiration study can be conducted, we recommend application of our adjusted version of the Wisconsin generalized coregonid bioenergetics model to lake whitefish populations in the field.

  18. Evidence of sexually dimorphic introgression in Pinaleno Mountain Apache trout

    USGS Publications Warehouse

    Porath, M.T.; Nielsen, J.L.

    2003-01-01

    The high-elevation headwater streams of the Pinaleno Mountains support small populations of threatened Apache trout Oncorhynchus apache that were stocked following the chemical removal of nonnative salmonids in the 1960s. A fisheries survey to assess population composition, growth, and size structure confirmed angler reports of infrequent occurrences of Oncorhynchus spp. exhibiting the external morphological characteristics of both Apache trout and rainbow trout O. mykiss. Nonlethal tissue samples were collected from 50 individuals in the headwaters of each stream. Mitochondrial DNA (mtDNA) sequencing and amplification of nuclear microsatellite loci were used to determine the levels of genetic introgression by rainbow trout in Apache trout populations at these locations. Sexually dimorphic introgression from the spawning of male rainbow trout with female Apache trout was detected using mtDNA and microsatellites. Estimates of the degree of hybridization based on three microsatellite loci were 10-88%. The use of nonlethal DNA genetic analyses can supplement information obtained from standard survey methods and be useful in assessing the relative importance of small and sensitive populations with a history of nonnative introductions.

  19. Effect of a ceiling fan ventilation system on finishing young bulls' health, behaviour and growth performance.

    PubMed

    Magrin, L; Brscic, M; Lora, I; Rumor, C; Tondello, L; Cozzi, G; Gottardo, F

    2016-11-24

    This research aimed at assessing the effects of a ceiling fan ventilation system on health, feeding, social behaviour and growth response of finishing young bulls fattened indoors during a mild summer season. A total of 69 Charolais young bulls were housed in six pens without any mechanical ventilation system (Control) and in six pens equipped with ceiling fans. The experimental period lasted 98 days from June until mid-September 2014. Four experimental days were considered in order to assess the effect of the ventilation system under two different microclimatic conditions: 2 alert days at monthly interval with temperature humidity index (THI) between 75 and 78, and 2 normal days with THI⩽74. Health and behaviour of the bulls were evaluated through 8-h observation sessions starting after morning feed delivery. The study was carried out during a rather cool summer with a climate average THI of 68.9 and 4 days with average THI>75. Despite these mild climate conditions, ceiling fans lowered litter moisture and acted as a preventive measure for bulls' dirtiness (odd ratio=47.9; 95% CI 19.6 to 117.4). The risk of abnormal breathing was increased for Control bulls (odd ratio=40.7; 95% CI 5.4 to 304.2). When exposed to alert THI conditions, respiration rate and panting scores increased and rumination duration dropped in Control bulls compared with bulls provided with a ceiling fan. During observations under alert THI, bulls spent less time eating, more time being inactive and consumed more water compared with normal THI conditions. Bulls' daily dry matter intake measured during the observation sessions decreased on alert compared with normal THI days (P<0.001) due to a drop of intake during the daylight hours. Ceiling fan treatment had no effect on bulls' growth performance or water consumption but these results most likely depended on the mild climate conditions. Ceiling fans proved to mitigate some of the negative effects of heat stress on bulls' behaviour (rumination

  20. Genetic differences in growth and survival of juvenile hatchery and wild steelhead trout, Salmo gairdneri

    USGS Publications Warehouse

    Reisenbichler, R.R.; McIntyre, J.D.

    1997-01-01

    Relative growth and survival of offspring from matings of hatchery and wild Deschutes River (Oregon) summer steelhead trout, Salmo gairdneri, were measured to determine if hatchery fish differ genetically from wild fish in traits that can affect the stock–recruitment relationship of wild populations. Sections of four natural streams and a hatchery pond were each stocked with genetically marked (lactate dehydrogenase genotypes) eyed eggs or unfed swim-up fry from each of three matings: hatchery × hatchery (HH), hatchery × wild (HW), and wild × wild (WW). In streams, WW fish had the highest survival and HW fish the highest growth rates when significant differences were found; in the hatchery pond, HH fish had the highest survival and growth rates. The hatchery fish were genetically different from wild fish and when they interbreed with wild fish may reduce the number of smolts produced. Hatchery procedures can be modified to reduce the genetic differences between hatchery and wild fish.

  1. National market cow and bull beef quality audit-1999: a survey of producer-related defects in market cows and bulls.

    PubMed

    Roeber, D L; Mies, P D; Smith, C D; Belk, K E; Field, T G; Tatum, J D; Scanga, J A; Smith, G C

    2001-03-01

    The 1999 National Market Cow and Bull Beef Quality Audit comprised face-to-face interviews with industry representatives (n = 49); in-plant evaluations of cattle in holding pens (n = 3,969), carcasses on harvest floors (n = 5,679), and in carcass coolers (n = 4,378); and a strategy workshop. Face-to-face interviews suggested that the beef industry was most frequently concerned about the presence of antibiotic residues in carcasses, presence of lead shot in carcasses, and price discovery for carcasses following excessive trimming of bruises and testing due to arthritic joints, pathogens, or antibiotic residues. Although live animal evaluations determined that 73.4% of beef cows, 60.8% of dairy cows, 63.7% of beef bulls, and 70.9% of dairy bulls did not exhibit evidence of lameness, losses due to lameness were greater (P < 0.05) than in the 1994 National Non-Fed Beef Quality Audit. In-plant audits revealed that 88.9, 10.3, and 88.2% of cow carcasses and 18.9, 21.2, and 52.9% of bull carcasses had inadequate muscling, arthritic joints, and at least 1 bruise, respectively, all of which resulted in greater (P < 0.05) losses than the same defects in 1994. Audits revealed that 88.9% of cow carcasses and 18.9% of bull carcasses were lightly muscled, resulting in greater (P < 0.05) losses for cow carcasses, and similar (P > 0.05) losses for bull carcasses, than the same defect in the 1994 audit. Also, 14.5 and 30.8% of cow carcasses and 6.9 and 5.9% of bull carcasses had excess external fat and yellow-colored external fat, respectively, which was an improvement (P < 0.05) over 1994 results. In aggregate, 24.1, 19.2, 7.2, 6.7, 9.5, and 1.1% of livers, tripe, hearts, heads, tongues, and whole cattle or carcasses, respectively, were condemned and 60.6, 2.4, and 46.5% of cattle had hide damage from latent defects, insect damage, and brands, respectively. Condemnation rates were generally lower (P < 0.05), but tongue condemnations and frequency of branded hides were higher (P

  2. Behavioral and histological effects of acrylamide in rainbow trout

    SciTech Connect

    Petersen, D.W.; Cooper, K.R.; Friedman, M.A.; Lech, J.J.

    1987-01-01

    A histological and behavioral study was used to assess whether acrylamide produced neurotoxic effects in rainbow trout. Swimming performance of trout exposed to 0, 12.5, or 25 mg/liter acrylamide for 15 days was unaffected. Swimming performance of animals exposed to 50 mg/liter acrylamide for a similar time period was compromised by morbidity and mortality of the animals in this treatment group. The absence of dose-related histological lesions in central neurons, peripheral neurons or muscle suggested that the observed deficit in swimming performance was due to a generalized toxic response. Acrylamide treatment produced dose-related lesions in the gill and liver of rainbow trout.

  3. PCB concentrations in lake trout (Salvelinus namaycush) are correlated to habitat use and lake characteristics.

    PubMed

    Guildford, S J; Muir, D C G; Houde, M; Evans, M S; Kidd, K A; Whittle, D M; Drouillard, K; Wang, X; Anderson, M R; Bronte, C R; Devault, D S; Haffner, D; Payne, J; Kling, H J

    2008-11-15

    This study considers the importance of lake trout habitat as a factor determining persistent organochlorine (OC) concentration. Lake trout is a stenothermal, cold water species and sensitive to hypoxia. Thus, factors such as lake depth, thermal stratification, and phosphorus enrichment may determine not only which lakes can support lake trout but may also influence among-lake variability in lake trout population characteristics including bioaccumulation of OCs. A survey of 23 lakes spanning much of the natural latitudinal distribution of lake trout provided a range of lake trout habitat to test the hypothesis that lake trout with greater access to littoral habitat for feeding will have lower concentrations of OCs than lake trout that are more restricted to pelagic habitat. Using the delta13C stable isotope signature in lake trout as an indicator of influence of benthic littoral feeding, we found a negative correlation between lipid-corrected delta13C and sigmaPCB concentrations supporting the hypothesis that increasing accessto littoral habitat results in lower OCs in lake trout. The prominence of mixotrophic phytoplankton in lakes with more contaminated lake trout indicated the pelagic microbial food web may exacerbate the biomagnification of OCs when lake trout are restricted to pelagic feeding. A model that predicted sigmaPCB in lake trout based on lake area and latitude (used as proximate variables for proportion of littoral versus pelagic habitat and accessibility to littoral habitat respectively) explained 73% of the variability in sigmaPCBs in lake trout in the 23 lakes surveyed.

  4. Ice processes affect habitat use and movements of adult cutthroat trout and brook trout in a Wyoming foothills stream

    USGS Publications Warehouse

    Lindstrom, J.W.; Hubert, W.A.

    2004-01-01

    Habitat use and movements of 25 adult cutthroat trout Oncorhynchus clarkii and 25 adult brook trout Salvelinus fontinalis from fall through winter 2002-2003 were assessed by means of radiotelemetry in a 7-km reach of a Rocky Mountains foothills stream. Temporal dynamics of winter habitat conditions were evaluated by regularly measuring the features of 30 pools and 5 beaver Castor canadensis ponds in the study reach. Groundwater inputs at three locations raised mean daily water temperatures in the stream channel during winter to 0.2-0.6??C and kept at least 250 m of the downstream channel free of ice, but the lack of surface ice further downstream led to the occurrence of frazil ice and anchor ice in pools and unstable habitat conditions for trout. Pools in segments that were not affected by groundwater inputs and beaver ponds tended to be stable and snow accumulated on the surface ice. Pools throughout the study reach tended to become more stable as snow accumulated. Both cutthroat trout and brook trout selected beaver ponds as winter progressed but tended to use lateral scour pools in proportion to their availability. Tagged fish not in beaver ponds selected lateral scour pools that were deeper than average and stable during winter. Movement frequencies by tagged fish decreased from fall through winter, but some individuals of both species moved during winter. Ice processes affected both the habitat use and movement patterns of cutthroat trout and brook trout in this foothills stream.

  5. Genetic characterization of hybridization and introgression between anadromous rainbow trout (Oncorhynchus mykiss irideus) and coastal cutthroat trout (O. clarki clarki).

    PubMed

    Young, W P; Ostberg, C O; Keim, P; Thorgaard, G H

    2001-04-01

    Interspecific hybridization represents a dynamic evolutionary phenomenon and major conservation problem in salmonid fishes. In this study we used amplified fragment length polymorphisms (AFLP) and mitochondrial DNA (mtDNA) markers to describe the extent and characterize the pattern of hybridization and introgression between coastal rainbow trout (Oncorhynchus mykiss irideus) and coastal cutthroat trout (O. clarki clarki). Hybrid individuals were initially identified using principle coordinate analysis of 133 polymorphic AFLP markers. Subsequent analysis using 23 diagnostic AFLP markers revealed the presence of F1, rainbow trout backcross, cutthroat trout backcross and later-generation hybrids. mtDNA analysis demonstrated equal numbers of F1 hybrids with rainbow and cutthroat trout mtDNA indicating reciprocal mating of the parental types. In contrast, rainbow and cutthroat trout backcross hybrids always exhibited the mtDNA from the recurrent parent, indicating a male hybrid mating with a pure female. This study illustrates the usefulness of the AFLP technique for generating large numbers of species diagnostic markers. The pattern of hybridization raises many questions concerning the existence and action of reproductive isolating mechanisms between these two species. Our findings are consistent with the hypothesis that introgression between anadromous populations of coastal rainbow and coastal cutthroat trout is limited by an environment-dependent reduction in hybrid fitness.

  6. Genetic characterization of hybridization and introgression between anadromous rainbow trout (oncorhynchus mykiss irideus) and coastal cutthroat trout (o. clarki clarki)

    USGS Publications Warehouse

    Young, W.P.; Ostberg, C.O.; Keim, P.; Thorgaard, G.H.

    2001-01-01

    Interspecific hybridization represents a dynamic evolutionary phenomenon and major conservation problem in salmonid fishes. In this study we used amplified fragment length polymorphisms (AFLP) and mitochondrial DNA (mtDNA) markers to describe the extent and characterize the pattern of hybridization and introgression between coastal rainbow trout (Oncorhynchus mykiss irideus) and coastal cutthroat trout (O. clarki clarki). Hybrid individuals were initially identified using principle coordinate analysis of 133 polymorphic AFLP markers. Subsequent analysis using 23 diagnostic AFLP markers revealed the presence of F1, rainbow trout backcross, cutthroat trout backcross and later-generation hybrids. mtDNA analysis demonstrated equal numbers of F1 hybrids with rainbow and cutthroat trout mtDNA indicating reciprocal mating of the parental types. In contrast, rainbow and cutthroat trout backcross hybrids always exhibited the mtDNA from the recurrent parent, indicating a male hybrid mating with a pure female. This study illustrates the usefulness of the AFLP technique for generating large numbers of species diagnostic markers. The pattern of hybridization raises many questions concerning the existence and action of reproductive isolating mechanisms between these two species. Our findings are consistent with the hypothesis that introgression between anadromous populations of coastal rainbow and coastal cutthroat trout is limited by an environment-dependent reduction in hybrid fitness.

  7. ASSESSMENT OF MAXIMUM SUSTAINABLE SWIMMING PERFORMANCE IN RAINBOW TROUT (ONCORHYNCHUS MYKISS)

    PubMed

    Wilson; Egginton

    1994-07-01

    Levels of swimming activity in fishes have been divided into three categories on the basis of the time a given speed can be maintained before the onset of fatigue (Beamish, 1978): sustained (more than 200 min), prolonged (20 s to 200 min) and burst swimming (less than 20 s). The locomotory capacity of a given species reflects both its lifestyle and its body form, although definitions of performance may vary. It is generally accepted that only the aerobic ('red') muscle fibres should be active at truly sustainable swimming speeds, i.e. at speeds that can be maintained indefinitely without fatigue. However, the standard laboratory method of evaluating the maximum sustainable swimming speed (Ucrit; Brett, 1964) almost certainly entails the recruitment of at least some of the rapidly fatigable fast glycolytic ('white') fibres at sub-critical speeds and undoubtedly complicates the evaluation of maximal cardiovascular performance. It would therefore be useful to have an objective and reproducible measure of truly sustainable performance that, by definition, relies solely on aerobic muscle activity. Electromyography (EMG) has been used to examine the pattern of white muscle recruitment following thermal acclimation in striped bass, Morine saxatilis (Sisson and Sidell, 1987). We wished to incorporate this method into a study of the acclimatory responses to chronic changes in environmental temperature of the cardiovascular and locomotory systems in rainbow trout (Wilson and Egginton, 1992). The present communication presents results on the cardiovascular performance and blood chemistry, at rest and during maximal aerobic exercise, of rainbow trout acclimated to 11 °C, as a validation of the methodology currently in use with fish acclimated to seasonal temperature extremes (Taylor et al. 1992). Different acclimation temperatures are known to produce compensatory changes in the relative proportions of red and white muscle mass (Sidell and Moerland, 1989). The aim of these

  8. Toxicokinetics of perfluorooctanoate (PFOA) in rainbow trout ...

    EPA Pesticide Factsheets

    Perfluoroalkyl acids (PFAAs) are widely used as stain resistant coatings for cloth, paper, and leather, and as surfactants, fire-fighting foams, and photographic developers. Individual PFAAs have been shown to accumulate in fish and wildlife; however, the extent of this accumulation varies widely. In general, the tendency of individual PFAAs to accumulate in fish is directly related to the length of a compound’s fluorinated carbon chain as well as the identity of the terminal group (sulfonate or carboxylate) which confers to the molecule its amphipathic character. Presently, however the mechanisms that underly these observations remain poorly understood. In the present study we investigated the kinetics of perfluorooctanoic acid (PFOA) in rainbow trout. PFOA is not accumulated by fish. We also know that it is eliminated by mammals in urine. Our hypothesis, therefore, was that renal elimination of PFOA limits its accumulation in fish. Trout injected with an intra-arterial dose of PFOA were sampled to obtain concentration time-course data for plasma, urine, and expired water. The data were then analyzed by compartmental modeling to estimate rates of renal and branchial clearance. Averaged across all animals, the renal clearance rate was about ten times higher than the branchial clearance rate, confirming our hypothesis. The results of this effort provide a clear explanation for the observed absence of PFOA accumulation in fish. Moreover, these results suggest th

  9. Characterization of proflavine metabolites in rainbow trout.

    PubMed

    Yu, Z; Hayton, W L; Chan, K K

    1997-04-01

    Proflavine (3,6-diaminoacridine) has potential for use as an antiinfective in fish, and its metabolism by rainbow trout was therefore studied. Fourteen hours after intraarterial bolus administration of 10 mg/kg of proflavine, three metabolites were found in liver and bile, and one metabolite was found in plasma using reversed-phase HPLC with UV detection at 262 nm. Treatment with hydrochloric acid converted the three metabolites to proflavine, which suggested that the metabolites were proflavine conjugates. Treatment with beta-glucuronidase and saccharic acid 1,4-lactone, a specific beta-glucuronidase inhibitor, revealed that two metabolites were proflavine glucuronides. For determination of UV-VIS absorption and mass spectra, HPLC-purified metabolites were isolated from liver. Data from these experiments suggested that the proflavine metabolites were 3-N-glucuronosyl proflavine (PG), 3-N-glucuronosyl,6-N-acetyl proflavine (APG), and 3-N-acetylproflavine (AP). The identities of the metabolites were verified by chemical synthesis. When synthetic PG and AP were compared with the two metabolites isolated from trout, they had the same molecular weight as determined by matrix-assisted, laser desorption ionization, time-of-flight MS. In addition, they coeluted on HPLC under different mobile phase conditions. Finally, the in vitro incubation with liver subcellular preparations confirmed this characterization and provided the evidence that APG can be formed by glucuronidation of AP or acetylation of PG.

  10. A rainbow trout lectin with multimeric structure.

    PubMed

    Jensen, L E; Thiel, S; Petersen, T E; Jensenius, J C

    1997-04-01

    A novel lectin has been identified in rainbow trout serum and plasma. The lectin binds to Sepharose (an agarose polymer) in a calcium-dependent manner. Glucose, N-acetyl-glucosamine, mannose, N-acetyl-mannosamine, L-fucose, maltose and alpha-methyl-mannoside are good inhibitors of this binding, whereas glucosamine and D-fucose inhibits to a lesser degree and mannosamine and galactose do not inhibit the binding to Sepharose. When analysed by SDS-PAGE under non-reducing conditions, the lectin appears as a characteristic ladder of bands with approximately 16 kDa between consecutive bands. Upon reduction, the lectin appears as a 16-kDa band. On size-exclusion chromatography of trout serum and plasma, the protein emerges over a broad range corresponding to sizes from about 2000 kDa to less than 200 kDa. The NH2-terminal sequence (AAENRNQXPPG) shows no significant homology with known proteins. Because of the characteristic appearance in non-reducing SDS-PAGE and the lectin activity, we propose to name the protein "ladderlectin."

  11. Sales Training for Army Recruiter Success: Interviews with Excellent Recruiters

    DTIC Science & Technology

    1987-11-01

    merit of an expert modeling system of the skills and strategies used by excel- lent Army recruiters. Neurolinguistic programming (NLP) was used as the...7. AUTHOR(&) 8. CONTRACT OR GRANT NUMBER(s) Steven R. Frieman 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT. PROJECT, TASK U.S...Recruiting 2M AUSTIRACT (rcnttm ame r orw am nssry i Identify by block number) s-This report describes a program of research on communication strategies and

  12. Bi-parentally inherited species-specific markers identify hybridization between rainbow trout and cutthroat trout subspecies

    USGS Publications Warehouse

    Ostberg, C.O.; Rodriguez, R.J.

    2004-01-01

    Eight polymerase chain reaction primer sets amplifying bi-parentally inherited species-specific markers were developed that differentiate between rainbow trout (Oncorhynchus mykiss) and various cutthroat trout (O. clarki) subspecies. The primers were tested within known F1 and first generation hybrid backcrosses and were shown to amplify codominantly within hybrids. Heterozygous individuals also amplified a slower migrating band that was a heteroduplex, caused by the annealing of polymerase chain reaction products from both species. These primer sets have numerous advantages for native cutthroat trout conservation including statistical genetic analyses of known crosses and simple hybrid identification.

  13. Novel molecular markers differentiate Oncorhynchus mykiss (rainbow trout and steelhead) and the O. clarki (cutthroat trout) subspecies

    USGS Publications Warehouse

    Ostberg, C.O.; Rodriguez, R.J.

    2002-01-01

    A suite of 26 PCR-based markers was developed that differentiates rainbow (Oncorhynchus mykiss) and coastal cutthroat trout (O. clarki clarki). The markers also differentiated rainbow from other cutthroat trout subspecies (O. clarki), and several of the markers differentiated between cutthroat trout subspecies. This system has numerous positive attributes, including: nonlethal sampling, high species-specificity and products that are easily identified and scored using agarose gel electrophoresis. The methodology described for developing the markers can be applied to virtually any system in which numerous markers are desired for identifying or differentiating species or subspecies.

  14. View of 200ton derrick interior support beneath it's bull wheel ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of 200-ton derrick interior support beneath it's bull wheel and mast centerline from from southeast. - Marshall Space Flight Center, Saturn V Dynamic Test Facility, East Test Area, Huntsville, Madison County, AL

  15. Alternatives for evaluating daughter performance of progeny-test bulls between official evaluations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In August 2007, USDA changed from calculating official genetic evaluations quarterly to triannually to coincide with the schedule for international evaluations. Industry cooperators requested that unofficial interim evaluations be initiated between official evaluations for progeny-test (PT) bulls to...

  16. Longitudinal strain bull's eye plot patterns in patients with cardiomyopathy and concentric left ventricular hypertrophy.

    PubMed

    Liu, Dan; Hu, Kai; Nordbeck, Peter; Ertl, Georg; Störk, Stefan; Weidemann, Frank

    2016-05-10

    Despite substantial advances in the imaging techniques and pathophysiological understanding over the last decades, identification of the underlying causes of left ventricular hypertrophy by means of echocardiographic examination remains a challenge in current clinical practice. The longitudinal strain bull's eye plot derived from 2D speckle tracking imaging offers an intuitive visual overview of the global and regional left ventricular myocardial function in a single diagram. The bull's eye mapping is clinically feasible and the plot patterns could provide clues to the etiology of cardiomyopathies. The present review summarizes the longitudinal strain, bull's eye plot features in patients with various cardiomyopathies and concentric left ventricular hypertrophy and the bull's eye plot features might serve as one of the cardiac workup steps on evaluating patients with left ventricular hypertrophy.

  17. In vitro assessment of sperm from bulls of high and low field fertility.

    PubMed

    Al Naib, A; Hanrahan, J P; Lonergan, P; Fair, S

    2011-07-01

    The aim of this study was to investigate the reasons for differences in field fertility of bulls following insemination with frozen-thawed semen. The study was carried out in two separate parts over two years and comparisons were made between 5 high and 4 low fertility Holstein Friesian bulls as determined by their either 90 day non-return rate (Year 1) or calving rate (Year 2). Two high fertility Limousin bulls were included in Year 1 for comparative purposes. The ability of sperm from each bull to penetrate artificial mucus was assessed (Year 1 = 7 replicates; Year 2 = 5 replicates). Glass capillary tubes (2 per bull per replicate) were filled with artificial mucus and incubated with sperm stained in 1% Hoechst 33342 for 30 min at 37 °C. The number of sperm were subsequently counted at 10 mm intervals along the tube between 40 and 80 mm markers. Sperm mitochondrial activity of each bull was assessed by the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide) assay (4 replicates in each year). Sperm were incubated with MTT for 1 h at 37 °C following which the absorbance of formazan was read using a spectrophotometer. Sperm viability after thawing was assessed for each bull using a live/dead sperm viability kit (Year 1 = 3 replicates; Year 2 = 4 replicates). A minimum of 250 cells were assessed per bull in each replicate and classified as either live or dead. Finally, the ability of sperm to fertilize oocytes in vitro and their ability to develop to blastocyst stage embryos were assessed (5 replicates in each year involving 220 to 306 oocytes per bull). Data transformation to normalize residuals was required for mucus sperm penetration (square root) and IVF (cleavage and blastocyst rate) results (arcsin). The mean number of sperm counted at each 10 mm mark between 40 and 80 mm was higher in the high fertility (56.0; 95% CI 39.5 to 75.3) compared to the low fertility (42.9; 95% CI 29.3 to 59.1) Holstein Friesian bulls but the difference did not

  18. Blood, Bull Terriers and Babesiosis: further evidence for direct transmission of Babesia gibsoni in dogs.

    PubMed

    Jefferies, R; Ryan, U M; Jardine, J; Broughton, D K; Robertson, I D; Irwin, P J

    2007-11-01

    This study reports on the epidemiology of Babesia gibsoni in American Pit Bull Terriers living in a region of western Victoria in southern Australia. Both American Pit Bull Terriers (n = 100) and other dog breeds (n = 51) were screened for B gibsoni using immunofluorescent antibody testing (IFAT) and/or polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). A questionnaire was also completed by each dog owner, ascertaining the husbandry and habits of the dogs sampled. Fourteen dogs were positive for B gibsoni using IFAT and/or PCR-RFLP and all were American Pit Bull Terriers. Dogs that were male and/or had been bitten by or were biters of other American Pit Bull Terriers were more likely to be B gibsoni positive, thus suggesting that blood-to-blood transmission contributes to the spread of this disease between dogs.

  19. Bulls grazing Kentucky 31 tall fescue exhibit impaired growth, semen quality, and decreased semen freezing potential

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Serum prolactin (PRL) and testosterone concentrations, body weight, body composition, semen quality, and semen freezing potential for bulls grazing the toxic tall fescue (Lolium arundinaceum [Schreb.] Darbysh. ¼ Schedonorous arundinaceum [Schreb.] Dumort.) cultivar Kentucky 31 (E+) compared with a n...

  20. A suite of twelve single nucleotide polymorphism markers for detecting introgression between cutthroat and rainbow trout.

    PubMed

    Harwood, Andrew S; Phillips, Ruth B

    2011-03-01

    A suite of 12 subspecies and species-specific single nucleotide polymorphism (species-specific SNP) markers was developed to distinguish rainbow trout (RT) Oncorhynchus mykiss from the four major subspecies of cutthroat trout: westslope cutthroat trout (WCT) Oncorhynchus clarki lewisi, Yellowstone cutthroat trout (YCT) Oncorhynchus clarki bouvieri, coastal cutthroat trout (CCT) Oncorhynchus clarki clarki, Lahontan cutthroat trout (LCT) Oncorhynchus clarki henshawi, and their hybrids. Several of the markers were linked to help strengthen hybrid determinations, and sex-specific species-specific SNP assays were also developed.

  1. Across the great divide: genetic forensics reveals misidentification of endangered cutthroat trout populations.

    PubMed

    Metcalf, Jessica L; Pritchard, Victoria L; Silvestri, Sarah M; Jenkins, Jazzmin B; Wood, John S; Cowley, David E; Evans, R Paul; Shiozawa, Dennis K; Martin, Andrew P

    2007-11-01

    Accurate assessment of species identity is fundamental for conservation biology. Using molecular markers from the mitochondrial and nuclear genomes, we discovered that many putatively native populations of greenback cutthroat trout (Oncorhynchus clarkii stomias) comprised another subspecies of cutthroat trout, Colorado River cutthroat trout (Oncorhynchus clarkii pleuriticus). The error can be explained by the introduction of Colorado River cutthroat trout throughout the native range of greenback cutthroat trout in the late 19th and early 20th centuries by fish stocking activities. Our results suggest greenback cutthroat trout within its native range is at a higher risk of extinction than ever before despite conservation activities spanning more than two decades.

  2. Central and peripheral cardiovascular, ventilatory, and motor effects of trout urotensin-II in the trout.

    PubMed

    Le Mével, Jean-Claude; Lancien, Frédéric; Mimassi, Nagi; Leprince, Jérôme; Conlon, J Michael; Vaudry, Hubert

    2008-05-01

    Urotensin-II (U-II) was originally considered to be exclusively the product of the caudal neurosecretory system (CNSS) of teleost fish, but it has now been demonstrated that U-II is widely expressed in peripheral tissues and nervous structures of species from lampreys to mammals. However, very little is known regarding the physiological effects of this peptide in its species of origin. In the present review, we summarize the most significant results relating to the cardiovascular, ventilatory, and motor effects of centrally and peripherally administered synthetic trout U-II in our experimental animal model, the unanesthetized trout Oncorhynchus mykiss. In addition, we compare the actions of U-II with those of other neurohormonal peptides, particularly with the actions of urotensin-I, a 41-amino acid residue peptide paralogous to corticotropin-releasing hormone that is co-localized with U-II within neurons of the CNSS.

  3. Molecular morphology and function of bull spermatozoa linked to histones and associated with fertility.

    PubMed

    de Oliveira, Rodrigo V; Dogan, Sule; Belser, Lauren E; Kaya, Abdullah; Topper, Einko; Moura, Arlindo; Thibaudeau, Giselle; Memili, Erdogan

    2013-09-01

    Sub-par fertility in bulls is influenced by alterations in sperm chromatin, and it might not be solved with increased sperm concentration in artificial insemination. Appropriate histone retention during sperm chromatin condensation plays critical roles in male fertility. The objective of this study was to determine failures of sperm chromatin condensation associated with abnormal persistence or accessibility of histones by aniline blue (ANBL) test, expression levels, and cellular localizations of one variant and two core histones (H3.3, H2B, and H4 respectively) in the spermatozoa of low-fertility (LF) vs high-fertility (HF) bulls. The expression levels and cellular localizations of histones in spermatozoa were studied using immunoblotting, immunocytochemistry, and staining methods. The bioinformatics focused on the sequence identity and evolutionary distance of these proteins among three mammalian species: bovine, mouse, and human. We demonstrated that ANBL staining was different within the LF (1.73 (0.55, 0.19)) and HF (0.67 (0.17, 0.06)) groups (P<0.0001), which was also negatively correlated with in vivo bull fertility (r=-0.90, P<0.0001). Although these histones were consistently detectable and specifically localized in bull sperm cells, they were not different between the two groups. Except H2B variants, H3.3 and H4 showed 100% identity and were evolutionarily conserved in bulls, mice and humans. The H2B variants were more conserved between bulls and humans, than in mice. In conclusion, we showed that H2B, H3.3, and H4 were detectable in bull spermatozoa and that sperm chromatin condensation status, changed by histone retention, is related to bull fertility.

  4. Metabolism of 7-ethyoxycoumarin by Isolated Perfused Rainbow Trout Livers

    EPA Science Inventory

    Isolated trout livers were perfused using methods designed to preserve tissue viability and function. Liver performance was evaluated by measuring O2 consumption, vascular resistance, K+ leakage, glucose flux, lactate flux, alanine aminotransferase leakage, and metabolic clearanc...

  5. Production of viable trout offspring derived from frozen whole fish

    PubMed Central

    Lee, Seungki; Seki, Shinsuke; Katayama, Naoto; Yoshizaki, Goro

    2015-01-01

    Long-term preservation of fish fertility is essential for the conservation of endangered fishes. However, cryopreservation techniques for fish oocytes and embryos have not yet been developed. In the present study, functional eggs and sperm were derived from whole rainbow trout that had been frozen in a freezer and stored without the aid of exogenous cryoprotectants. Type A spermatogonia retrieved from frozen-thawed whole trout remained viable after freezing duration up to 1,113 days. Long-term-frozen trout spermatogonia that were intraperitoneally transplanted into triploid salmon hatchlings migrated toward the recipient gonads, where they were incorporated, and proliferated rapidly. Although all triploid recipients that did not undergo transplantation were functionally sterile, 2 of 12 female recipients and 4 of 13 male recipients reached sexual maturity. Eggs and sperm obtained from the salmon recipients were capable of producing donor-derived trout offspring. This methodology is thus a convenient emergency tool for the preservation of endangered fishes. PMID:26522018

  6. View west of reserve basin of submarine trout and frigate ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View west of reserve basin of submarine trout and frigate Edward E. McDonnell - Naval Base Philadelphia-Philadelphia Naval Shipyard, Reserve Basin & Marine Railway, League Island, Philadelphia, Philadelphia County, PA

  7. Comparison of biochemical parameters of rainbow trout (Oncorhynchus mykiss) reared in two different trout farms'

    NASA Astrophysics Data System (ADS)

    Karatas, Tayfun

    2016-04-01

    The aim of this study was to compare biochemical parameters of cultured rainbow trouts (Oncorhynchus mykiss, Walbaum, 1972) reared in two different trout farms' (Agri and Erzurum). The average weights of fish were 150±10gr for first station (Agri), 230±10gr for second station (Erzurum). Fishes used in research were randomly caught from pools, and fifteen pieces were used for each group. Fishes were fed with commercial trout feed with 45-50% crude protein twice a day. The levels of AST, ALT, LDL, total cholesterol and triglyceride in the second station (Erzurum) were found to be higher (p<0.05) than that of first station (Agri). Whereas, the levels of HDL in the second station (Erzurum) were found to be lower (p<0.05) than that of first station (Agri). Differences in the levels of total cholesterol and AST, ALT, HDL, LDL, triglyceride may be associated with size, sex, sexual maturity and environmental conditions (temperature, pH, hardness and dissolved oxygen).

  8. Rainbow trout (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis) 7-day survival and growth test method.

    PubMed

    Lazorchak, James M; Smith, Mark E

    2007-10-01

    A short-term method was developed in this study for conducting subchronic survival and growth renewal toxicity tests with rainbow trout (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis). Previously published early life-stage methods for various salmonid species involve test durations of 30 to 90 days. This trout method, however, follows a previously published 7-day fathead minnow (Pimephales promelas) growth method. The tests performed in this study measured subchronic growth and survival effects using standard reference toxicants (ammonium chloride, potassium chloride, phenol, and zinc sulfate), receiving water, and effluent samples. The test results were compared with performance criteria and results for 7-day survival and growth tests with P. promelas to determine the level of comparability between the two species. The results from tests with both salmonid species indicated that this 7-day survival and growth test method using O. mykiss and S. fontinalis provides reproducible results with various reference toxicant materials and can be used successfully to detect potential toxicity in environmental samples.

  9. Recruiting for Prior Service Market

    DTIC Science & Technology

    2008-06-01

    perceptions, expectations and issues for re-enlistment • Develop potential marketing and advertising tactics and strategies targeted to the defined...01 JUN 2008 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Recruiting for Prior Service Market 5a. CONTRACT NUMBER 5b. GRANT...Command First Handshake to First Unit of Assignment An Army of One Proud to Be e e to Serve Recruiting for Prior Service Market MAJ Eric Givens / MAJ Brian

  10. Effect of temperament and prolonged transportation on endocrine and functional variables in young beef bulls.

    PubMed

    Fazio, E; Medica, P; Cravana, C; Cavaleri, S; Ferlazzo, A

    The purpose of this study was to evaluate the effect of prolonged transportation on adrenocorticotropic hormone (ACTH), cortisol, total and free triiodothyronine (T(3), fT(3)) and thyroxine (T(4), fT(4)) concentrations, and functional variables (heart rate (HR), respiratory rate (RR) and rectal temperature (RT)) in calm and temperamental Limousin young beef bulls. Exit velocity measurement was used to classify bulls' temperament as calm (group I: consisted of eight slowest bulls) and temperamental (group II: consisted of five fastest bulls). Calm subjects showed an increase of ACTH (P<0.05) and T(4) (P<0.01) concentrations after transportation compared with before transportation values. Temperamental subjects showed higher ACTH (P<0.01) concentrations before transportation, and lower T(4) (P<0.05) and fT(4) (P<0.001) concentrations after transportation than calm subjects. Related to functional variables, temperamental young beef bulls showed a decrease of RT (P<0.05) after transportation compared with before values, higher RT (P<0.001) before transportation, and higher HR (P<0.001) and RR (P<0.01) after transportation than calm subjects. Data obtained suggest that longer periods of transportation could minimise the magnitude and duration of the endocrine and functional responses to stress of young beef bulls; such responses probably decrease or disappear during transport, in accordance with animal temperament.

  11. Acute BRSV infection in young AI bulls: effect on sperm quality.

    PubMed

    Alm, K; Koskinen, E; Vahtiala, S; Andersson, M

    2009-06-01

    Bovine respiratory syncytial virus (BRSV) infection is an important part of the calf pneumonia complex, occasionally affecting even adult cattle. However, the pathogenicity of BRSV in animals older than 6 months is often neglected. Finland is free of many contagious diseases in farm animals, and this gives a good opportunity to study the effects of specific pathogens on bovine reproduction. This report describes the deteriorating effects of BRSV epizootics on sperm morphology and fertility of young dairy bulls (n = 79) at a bull station. More than half of the young bulls had a clinical respiratory disease caused by BRSV during their quarantine when they were 6 months old. Four of seven subsequent quarantine groups were affected. Six months later, when these seropositive bulls (n = 54) came into semen production, they had poorer sperm morphology, and the proportion of normal spermatozoa was 74.1% in BRSV-seropositive animals compared with 81.2% in seronegative bulls (n = 25) (p = 0.035). Field fertility was also slightly affected, the 60-day non-return rates were 75.2% and 76.8% for BRSV seropositive and seronegative bulls respectively (p = 0.014). Potential reasons for lowered sperm quality are discussed here.

  12. Short communication: Genetic analysis of dairy bull fertility from field data of Brown Swiss cattle.

    PubMed

    Tiezzi, F; Maltecca, C; Penasa, M; Cecchinato, A; Bittante, G

    2013-01-01

    The aim of this study was to estimate heritability and repeatability of dairy bull fertility in Italian Brown Swiss cattle. Bull fertility indicators were calving per service and nonreturn rate at 56 d after service. Data included 124,206 inseminations carried out by 86 technicians on 28,873 heifers and cows in 1,400 herds. Services were recorded from 1999 to 2008 and were performed with semen from 306 AI Brown Swiss bulls. Data were analyzed with a threshold animal model, which included the fixed effects of parity by class of days in milk of the inseminated cow (age at insemination for heifers), year-season of insemination, and status of the service bull at the time of insemination (progeny testing or proven), and the random effects of herd, technician, additive genetic, and permanent environment of inseminated heifer/cow and service bull, and residual. Also, genetic covariance between heifer/cow and service bull effects was considered in the model. Heritability and repeatability were 0.0079 and 0.0100 for nonreturn rate at 56 d after service, and 0.0153 and 0.0202 for calving per service, respectively. The low estimates obtained in the present study indicate that selection for male fertility using field data is hardly pursuable.

  13. Virulence of Flavobacterium columnare genomovars in rainbow trout Oncorhynchus mykiss.

    PubMed

    Evenhuis, Jason P; LaFrentz, Benjamin R

    2016-08-09

    Flavobacterium columnare is the causative agent of columnaris disease and is responsible for significant economic losses in aquaculture. F. columnare is a Gram-negative bacterium, and 5 genetic types or genomovars have been described based on restriction fragment length polymorphism of the 16S rRNA gene. Previous research has suggested that genomovar II isolates are more virulent than genomovar I isolates to multiple species of fish, including rainbow trout Oncorhynchus mykiss. In addition, improved genotyping methods have shown that some isolates previously classified as genomovar I, and used in challenge experiments, were in fact genomovar III. Our objective was to confirm previous results with respect to genomovar II virulence, and to determine the susceptibility of rainbow trout to other genomovars. The virulence of 8 genomovar I, 4 genomovar II, 3 genomovar II-B, and 5 genomovar III isolates originating from various sources was determined through 3 independent challenges in rainbow trout using an immersion challenge model. Mean cumulative percent mortality (CPM) of ~49% for genomovar I isolates, ~1% for genomovar II, ~5% for the II-B isolates, and ~7% for the III isolates was observed. The inability of genomovar II isolates to produce mortalities in rainbow trout was unanticipated based on previous studies, but may be due to a number of factors including rainbow trout source and water chemistry. The source of fish and/or the presence of sub-optimal environment may influence the susceptibility of rainbow trout to different F. columnare genomovars.

  14. Creatine metabolism differs between mammals and rainbow trout (Oncorhynchus mykiss).

    PubMed

    Borchel, Andreas; Verleih, Marieke; Rebl, Alexander; Kühn, Carsten; Goldammer, Tom

    2014-01-01

    Creatine plays an important role in the cell as an energy buffer. As the energy system is a basic element of the organism it may possibly contribute to differences between rainbow trout strains selected for the traits growth and robustness, respectively. The cDNA sequences of creatine-related genes encoding glycine amidinotransferase (GATM), guanidinoacetate N-methyltransferase (GAMT), creatine kinase muscle-type (CKM) and creatine transporter 1 (CT1, encoded by gene solute carrier family 6, member 8 (SLC6A8)) were characterized in rainbow trout. Transcripts of the respective genes were quantified in kidney, liver, brain and skeletal muscle in both trout strains that had been acclimated to different temperatures. Several differences between the compared trout strains were found as well as between temperatures indicating that the energy system may contribute to differences between both strains. In addition to that, the expression data showed clear differences between the creatine system in rainbow trout and mammals, as the spatial distribution of the enzyme-encoding gene expression was clearly different from the patterns described for mammals. In rainbow trout, creatine synthesis seems to take place to a big extent in the skeletal muscle.

  15. Conservation of native Pacific trout diversity in western North America

    USGS Publications Warehouse

    Penaluna, Brooke E.; Abadía-Cardoso, Alicia; Dunham, Jason; García de León, Francisco J; Gresswell, Robert E.; Luna, Arturo Ruiz; Taylor, Eric B.; Shepard, Bradley B.; Al-Chokhachy, Robert K.; Muhlfeld, Clint C.; Bestgen, Kevin R.; Rogers, Kevin H.; Escalante, Marco A; Keeley, Ernest R; Temple, Gabriel; Williams, Jack E.; Matthews, Kathleen; Pierce, Ron; Mayden, Richard L.; Kovach, Ryan; Garza, John Carlos; Fausch, Kurt D.

    2016-01-01

    Pacific trout Oncorhynchus spp. in western North America are strongly valued in ecological, socioeconomic, and cultural views, and have been the subject of substantial research and conservation efforts. Despite this, the understanding of their evolutionary histories, overall diversity, and challenges to their conservation is incomplete. We review the state of knowledge on these important issues, focusing on Pacific trout in the genus Oncorhynchus. Although most research on salmonid fishes emphasizes Pacific salmon, we focus on Pacific trout because they share a common evolutionary history, and many taxa in western North America have not been formally described, particularly in the southern extent of their ranges. Research in recent decades has led to the revision of many hypotheses concerning the origin and diversification of Pacific trout throughout their range. Although there has been significant success at addressing past threats to Pacific trout, contemporary and future threats represented by nonnative species, land and water use activities, and climate change pose challenges and uncertainties. Ultimately, conservation of Pacific trout depends on how well these issues are understood and addressed, and on solutions that allow these species to coexist with a growing scope of human influences.

  16. Delineation of sympatric morphotypes of lake trout in Lake Superior

    USGS Publications Warehouse

    Moore, Seth A.; Bronte, Charles R.

    2001-01-01

    Three morphotypes of lake trout Salvelinus namaycush are recognized in Lake Superior: lean, siscowet, and humper. Absolute morphotype assignment can be difficult. We used a size-free, whole-body morphometric analysis (truss protocol) to determine whether differences in body shape existed among lake trout morphotypes. Our results showed discrimination where traditional morphometric characters and meristic measurements failed to detect differences. Principal components analysis revealed some separation of all three morphotypes based on head and caudal peduncle shape, but it also indicated considerable overlap in score values. Humper lake trout have smaller caudal peduncle widths to head length and depth characters than do lean or siscowet lake trout. Lean lake trout had larger head measures to caudal widths, whereas siscowet had higher caudal peduncle to head measures. Backward stepwise discriminant function analysis retained two head measures, three midbody measures, and four caudal peduncle measures; correct classification rates when using these variables were 83% for leans, 80% for siscowets, and 83% for humpers, which suggests the measures we used for initial classification were consistent. Although clear ecological reasons for these differences are not readily apparent, patterns in misclassification rates may be consistent with evolutionary hypotheses for lake trout within the Laurentian Great Lakes.

  17. Seasonal movement of brown trout in the Clinch River, Tennessee

    USGS Publications Warehouse

    Bettinger, J.M.; Bettoli, P.W.

    2004-01-01

    We used radiotelemetry to monitor the seasonal movements of trophy-size brown trout Salmo trutta in the Clinch River below Norris Dam, Tennessee, to determine whether establishing a special-regulation reach to reduce fishing mortality was a viable management option. Fifteen brown trout (size range, 430-573 mm total length) collected from the river were implanted with radio transmitters between November 1997 and May 1998. Forty-seven percent of these fish died or expelled their transmitters within 50 d postsurgery. The range of movement for surviving brown trout was significantly larger in fall (geometric mean range = 5,111 m) than in any other season. Four brown trout that were monitored for more than 1 year exhibited a limited range of movement (5 km) during the fall season, presumably to spawn. Brown trout also moved more during the fall than in any other season. Harvest restrictions applied to a specific reach of the Clinch River would reduce the exploitation of brown trout in that reach for most of the year but not during the fall, when many fish undertake extensive spawning migrations.

  18. Predation on lake trout eggs and fry: A modeling approach

    USGS Publications Warehouse

    Savino, Jacqueline F.; Hudson, Patrick L.; Fabrizio, Mary C.; Bowen, Charles A.

    1999-01-01

    A general model was developed to examine the effects of multiple predators on survival of eggs and fry of lake trout, Salvelinus namaycush, associated with spawning reefs. Three kinds of predation were simulated: epibenthic egg predators consuming eggs on the substrate surface during spawning, interstitial egg predators that can move in rocky substrate and consume incubating eggs, and fry predators. Also simulated was the effect of water temperature on predation rates. The model predicted that interstitial predation on eggs accounted for most (76 to 81%) of the predation on early life history stages of lake trout; epibenthic egg predation (12 to 19%) and fry predation (0 to 12%) had less effect on lake trout survival. Initial predation conditions chosen for the model were: epibenthic egg predation peaked at 2 eggs/mA?/d over 30 d, insterstitial egg predation at 2 eggs/mA?/d over 180 d, and fry predation at 1 fry/mA?/d over 60 d. With a starting egg density of 100 eggs/mA? and initial predation conditions, no lake trout were estimated to survive to swim-up. At egg densities of 250 eggs/mA?, 36% of the lake trout survived. At the highest egg densities examined, 500 to 1,000 eggs/mA?, estimated survival increased to about 70 to 80%. Simulated survival rates of lake trout decreased dramatically as predation rate increased but were not as sensitive to increases in the duration of predation.

  19. 20 CFR 655.156 - Recruitment report.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Requirements of a recruitment report. The employer must prepare, sign, and date a written recruitment report... job opportunity up to the date of the preparation of the recruitment report, and the disposition...

  20. Recruiting Students into Nursing: Prior Questions.

    ERIC Educational Resources Information Center

    Hipps, Opal S.

    1983-01-01

    Raises fundamental questions regarding student recruitment: (1) why recruit students into nursing? (2) what are the issues that determine whether a school should have a nursing program? and (3) what are students being recruited into? (JOW)

  1. MicroTrout: A comprehensive, genome-wide miRNA target prediction framework for rainbow trout, Oncorhynchus mykiss.

    PubMed

    Mennigen, Jan A; Zhang, Dapeng

    2016-12-01

    Rainbow trout represent an important teleost research model and aquaculture species. As such, rainbow trout are employed in diverse areas of biological research, including basic biological disciplines such as comparative physiology, toxicology, and, since rainbow trout have undergone both teleost- and salmonid-specific rounds of genome duplication, molecular evolution. In recent years, microRNAs (miRNAs, small non-protein coding RNAs) have emerged as important posttranscriptional regulators of gene expression in animals. Given the increasingly recognized importance of miRNAs as an additional layer in the regulation of gene expression and hence biological function, recent efforts using RNA- and genome sequencing approaches have resulted in the creation of several resources for the construction of a comprehensive repertoire of rainbow trout miRNAs and isomiRs (variant miRNA sequences that all appear to derive from the same gene but vary in sequence due to post-transcriptional processing). Importantly, through the recent publication of the rainbow trout genome (Berthelot et al., 2014), mRNA 3'UTR information has become available, allowing for the first time the genome-wide prediction of miRNA-target RNA relationships in this species. We here report the creation of the microtrout database, a comprehensive resource for rainbow trout miRNA and annotated 3'UTRs. The comprehensive database was used to implement an algorithm to predict genome-wide rainbow trout-specific miRNA-mRNA target relationships, generating an improved predictive framework over previously published approaches. This work will serve as a useful framework and sequence resource to experimentally address the role of miRNAs in several research areas using the rainbow trout model, examples of which are discussed.

  2. QSAR trout toxicity models on aromatic pesticides.

    PubMed

    Slavov, Svetoslav; Gini, Giuseppina; Benfenati, Emilio

    2008-11-01

    The pesticides originally designed to kill target organisms are dangerous for many other wild species. Since they are applied directly to the environment, they can easily reach the water basins and the topsoil. A dataset of 125 aromatic pesticides with well-expressed aquatic toxicity towards trout was subjected to quantitative structure activity relationships (QSAR) analysis aimed to establish the relationship between their molecular structure and biological activity. A literature data for LC50 concentration killing 50% of fish was used. In addition to the standard 2D-QSAR analysis, a comparative molecular field analysis (CoMFA) analysis considering the electrostatic and steric properties of the molecules was also performed. The CoMFA analysis helped the recognition of the steric interactions as playing an important role for aquatic toxicity. In addition, the transport properties and the stability of the compounds studied were also identified as important for their biological activity.

  3. Habitat Suitability Index Models: Rainbow trout

    USGS Publications Warehouse

    Raleigh, Robert F.; Hickman, Terry; Solomon, R. Charles; Nelson, Patrick C.

    1984-01-01

    A review and synthesis of existing information were used to develop riverine and lacustrine habitat models for rainbow trout (Salmo gairdneri), a freshwater species. The models are scaled to produce an index of habitat suitability between 0 (unsuitable habitat) to 1 (optimally suitable habitat) for freshwater areas of the continental United States. Other habitat suitability models found in the literature are also included. 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 Fallfish habitat.

  4. Determination of benzocaine in rainbow trout plasma

    USGS Publications Warehouse

    Bernardy, Jeffery A.; Coleman, K.S.; Stehly, G.R.; Gingerich, William H.

    1996-01-01

    A liquid chromatographic method is described for analysis of benzocaine (BZ), a proposed fish anesthetic, in rainbow trout plasma, Mean recoveries of BZ from plasma samples fortified at 44-10 100 ng/mL were 96-100%. The method detection limit is 10 ng/mL, and the limit of quantitation is 37 ng/mL. Acetylation of BZ occurs in whole blood after storage at room temperature (i.e., 21 degrees C) for 10 min. However, no acetylation of BZ was detected in plasma samples held at room temperature for 4 h, Mean method precision for plasma samples with incurred BZ residue is similar to that for fortified samples in the same concentration range (relative standard deviations of 0.9 and 1.2%, respectively).

  5. Assessment of sperm morphology in zebu bulls, under field conditions in the tropics.

    PubMed

    Chacón, J

    2001-04-01

    Sperm morphology was studied in 302 extensively managed Zebu bulls (aged 1.5-9 years), classified as sound (n=166) or unsound (n=136) for breeding, under field conditions in the dry tropics of Costa Rica. Single semen samples were collected by electro-ejaculation and fixed in formol-saline solution immediately after collection. Sperm morphology was determined in the field on wet smears using a microscope equipped with phase-contrast optics, and further determined in the laboratory on air-dried smears stained with carbol-fuchsin. The frequencies of sperm abnormalities (such as abnormal acrosome, head, neck, mid-piece, tail, and presence of cytoplasmic droplets) were recorded as a percentage of the total number of counted spermatozoa (400 cells). Zebu bulls considered unsound for breeding showed a higher mean prevalence (p < 0.05) of knobbed acrosomes (4.0 versus 0.9%), head defects [specifically, nuclear invaginations and heads with abnormal shapes and sizes (27.6 versus 4.0%)], abnormal tails (11.2 versus 4.7%), and proximal droplets (8.4 versus 1.6%), compared with bulls considered sound for breeding. In these latter bulls, the abnormality most commonly seen was the presence of single bent tails with an entrapped cytoplasmic droplet (3.0 +/- 3.7%). Young Zebu bulls (i.e. bulls under 2 years of age) showed a higher percentage of missing acrosomes, and proximal cytoplasmic droplets, than older sires (12.1 versus 2.4%, and 23.9 versus 3.6%, respectively; p < 0.05), interpreted as an indication of low ejaculation frequency and sexual immaturity, respectively. Bulls with a long scrotum and soft testicular consistency (TC) at palpation showed higher percentages of abnormal sperm heads in the ejaculate than bulls with a normal scrotal length (SL) and a normal TC (32.7 versus 12.8% and 30.7 versus 10.3%, respectively; p < 0.05). In addition, Zebu bulls with a scrotal circumference (SC) < or = 30 cm showed a higher prevalence of proximal cytoplasmic droplets than bulls

  6. Effects of hybridization between nonnative Rainbow Trout and native Westslope Cutthroat Trout on fitness-related traits

    USGS Publications Warehouse

    Drinan, Daniel P.; Webb, Molly A. H.; Naish, Kerry A.; Kalinowski, Steven T.; Boyer, Matthew C.; Steed, Amber C.; Shepard, Bradley B.; Muhlfeld, Clint C.

    2015-01-01

    Hybridization between introduced and native fauna is a risk to native species and may threaten the long-term persistence of numerous taxa. Rainbow Trout Oncorhynchus mykiss has been one of the most widely introduced species around the globe and often hybridizes with native Cutthroat Trout O. clarkii in the Rocky Mountains. Previous work has shown that hybridization negatively affects reproductive success, but identification of the traits contributing to that reduction has been elusive. In this study, we used a combination of field and laboratory techniques to assess how hybridization with Rainbow Trout affects seven traits during several stages of Westslope Cutthroat Trout development: embryonic survival, ova size, ova energy concentration, sperm motility, juvenile weight, juvenile survival, and burst swimming endurance. Rainbow Trout admixture was correlated with an increase in embryonic survival and ova energy concentration but with a decrease in juvenile weight and burst swimming endurance. These correlations differed from previously observed patterns of reproductive success and likely do not explain the declines in reproductive success associated with admixture. Future investigation of additional, unstudied traits and the use of different environments may shed light on the traits responsible for reproductive success in admixed Cutthroat Trout.

  7. Comparative susceptibility of Atlantic salmon, lake trout and rainbow trout to Myxobolus cerebralis in controlled laboratory exposures

    USGS Publications Warehouse

    Blazer, V.S.; Densmore, Christine L.; Schill, W.B.; Cartwright, Deborah D.; Page, S.J.

    2004-01-01

    The susceptibility of lake trout Salvelinus namaycush, rainbow trout Oncorhynchus mykiss and Atlantic salmon Salmo salar to Myxobolus cerebralis, the causative agent of whirling disease, was compared in controlled laboratory exposures. A total of 450 (225 for each dose) fry for each species were exposed to a low (200 spores per fish) or high (2000 spores per fish) dose of the infective triactinomyxon. At 22 wk post-exposure, 60 fish from each group, as well as controls for each species, were examined for clinical signs (whirling behavior, blacktail, deformed heads and skeletal deformities), microscopic lesions, and presence of spores. Rainbow trout were highly susceptible to infection, with 100% being positive for spores and with microscopic pathological changes in both exposure groups. Rainbow trout were the only species to show whirling behavior and blacktail. Atlantic salmon were less susceptible, with only 44 and 61% being positive for spores, respectively, in the low and high dose groups, while 68 and 75%, respectively, had microscopic pathology associated with cartilage damage. Rainbow trout heads contained mean spore concentrations of 2.2 (low dose) or 4.0 (high dose) ?? 106 spores g tissue-1. The means for positive Atlantic salmon (not including zero values) were 1.7 (low) and 7.4 (high) ?? 104 spores g tissue-1. Lake trout showed no clinical signs of infection, were negative for spores in both groups and showed no histopathological signs of M. cerebralis infection.

  8. Mechanisms for extraordinary optical transmission through bull's eye structures.

    PubMed

    Carretero-Palacios, S; Mahboub, O; Garcia-Vidal, F J; Martin-Moreno, L; Rodrigo, Sergio G; Genet, C; Ebbesen, T W

    2011-05-23

    We analyze both experimentally and theoretically the physical mechanisms that determine the optical transmission through deep sub-wavelength bull's eye structures (concentric annular grooves surrounding a circular hole). Our analysis focus on the transmission resonance as a function of the distance between the central hole and its nearest groove. We find that, for that resonance, each groove behaves almost independently, acting as an optical cavity that couples to incident radiation, and reflecting the surface plasmons radiated by the other side of the same cavity. It is the constructive contribution at the central hole of these standing waves emitted by independent grooves which ends up enhancing transmission. Also for each groove the coupling and reflection coefficients for surface plasmons are incorporated into a phenomenological Huygens-Fresnel model that gathers the main mechanisms to enhance transmission. Additionally, it is shown that the system presents a collective resonance in the electric field that does not lead to resonant transmission, because the fields radiated by the grooves do not interfere constructively at the central hole.

  9. Arrangement of beta tubulin in bull spermatozoa during nuclei decondensation.

    PubMed

    Gómez-Conde, E; Romero-Pastrana, F; Vargas-Mejía, M A; Delgado, N M; Reyes, R

    2004-01-01

    Eukaryotic cells have internal scaffolding of microtubules cytoskeleton that gives them their characteristic shapes. We analyzed by immuno-fluorescence the shift and distribution of tubuline during in vitro bull sperm nuclei swelling by the action of heparin-reduced glutathione physiological decondensing agents. Sperm tubulin display a pattern that shows tubulin fluorescence all over the head, leaving the acrosome tip devoid of tubulin. In the second stage we can observe that the acrosomal zone is practically devoid of fluorescence and a net of fluorescent microtubules that seems to be anchored in the basal plate in the postacrosomal region. It is also possible to observe green spots of tubulin fluorescence in the nucleus periphery, that might represent clusters of chromatin hub-like bodies and/or the microtubule organizing center (MTOC). In the third stage, practically all tubulin moves backwards to the basal plate in the neck region of the sperm nuclei remaining in only the green fluorescence spots in the periphery of the swollen sperm nuclei. The results allow us to assume that tubulin mechanism rearrangement is considered to be necessary for the normal fertilization process.

  10. Normal SPECT thallium-201 bull's-eye display: gender differences.

    PubMed

    Eisner, R L; Tamas, M J; Cloninger, K; Shonkoff, D; Oates, J A; Gober, A M; Dunn, D W; Malko, J A; Churchwell, A L; Patterson, R E

    1988-12-01

    The bull's-eye technique synthesizes three-dimensional information from single photon emission computed tomographic 201TI images into two dimensions so that a patient's data can be compared quantitatively against a normal file. To characterize the normal database and to clarify differences between males and females, clinical data and exercise electrocardiography were used to identify 50 males and 50 females with less than 5% probability of coronary artery disease. Results show inhomogeneity of the 201TI distributions at stress and delay: septal to lateral wall count ratios are less than 1.0 in both females and males; anterior to inferior wall count ratios are greater than 1.0 in males but are approximately equal to 1.0 in females. Washout rate is faster in females than males at the same peak exercise heart rate and systolic blood pressure, despite lower exercise time. These important differences suggest that quantitative analysis of single photon emission computed tomographic 201TI images requires gender-matched normal files.

  11. Environmental Enrichment in Kennelled Pit Bull Terriers (Canis lupus familiaris).

    PubMed

    Kiddie, Jenna; Bodymore, Anna; Dittrich, Alex

    2017-03-23

    Although social enrichment can be considered beneficial in helping dogs cope with the kennel environment, when taking individual needs into account, it places a large demand on the carers and may not be appropriate in under-resourced kennels. Some kennels are also designed in such a way that there is too much social interaction, in that individuals cannot choose to distance themselves from conspecifics. This study therefore aimed to assess the effects of easily accessible enrichment on the behaviour of kennelled Pit Bull Terrier type dogs rescued from a dog-fighting ring in the Philippines. Thirty-six dogs were allocated to one of three treatment groups following a matched-subject design: (i) cardboard bed provision; (ii) coconut provision; and (iii) visual contact with dogs housed in adjacent cages obstructed with cardboard partitions. Behavioural diversity and the duration and frequency of individual behaviours were analysed using linear mixed-effect models. Yawning frequencies and time spent lying down and sitting decreased during treatment. No particular treatment was more influential in these behavioural changes. In conclusion, enrichment, regardless of type, affected the dogs' behaviour, with some effects depending on the sex of the dogs. Therefore, it is possible to cheaply and sustainably enrich the lives of dogs living in highly constrained environments, however, further research is required to refine the methods used.

  12. Fish models for environmental carcinogenesis: the rainbow trout.

    PubMed Central

    Bailey, G S; Williams, D E; Hendricks, J D

    1996-01-01

    Progress over the past 30 years has revealed many strengths of the rainbow trout as an alternative model for environmental carcinogenesis research. These include low rearing costs, an early life-stage ultrasensitive bioassay, sensitivity to many classes of carcinogen, a well-described tumor pathology, responsiveness to tumor promoters and inhibitors, and a mechanistically informative nonmammalian comparative status. Low-cost husbandry, for example, has permitted statistically challenging tumor study designs with up to 10,000 trout to investigate the quantitative interrelationships among carcinogen dose, anticarcinogen dose, DNA adduct formation, and final tumor outcome. The basic elements of the trout carcinogen bioassay include multiple exposure routes, carcinogen response, husbandry requirements, and pathology. The principal known neoplasms occur in liver (mixed hepatocellular/cholangiocellular adenoma and carcinoma, hepatocellular carcinoma), kidney (nephroblastoma), swim bladder (adenopapilloma), and stomach (adenopapilloma). Trout possess a complex but incompletely characterized array of cytochromes P450, transferases, and other enzymic systems for phase I and phase II procarcinogen metabolism. In general, trout exhibit only limited capacity for DNA repair, especially for removal of bulky DNA adducts. This factor, together with a high capacity for P450 bioactivation and negligible glutathione transferase-mediated detoxication of the epoxide, accounts for the exceptional sensitivity of trout to aflatoxin B1 carcinogenesis. At the gene level, all trout tumors except nephroblastoma exhibit variable and often high incidences of oncogenic Ki-ras gene mutations. Mutations in the trout p53 tumor suppressor gene have yet to be described. There are many aspects of the trout model, especially the lack of complete organ homology, that limit its application as a surrogate for human cancer research. Within these limitations, however, it is apparent that trout and other

  13. Characterization of Park Visitors, Visitation Levels, and Associated Economic Impacts of Recreation at Bull Shoals, Norfork, and Table Rock Lakes

    DTIC Science & Technology

    2010-11-01

    Economic Impacts of Recreation at Bull Shoals, Norfork, and Table Rock Lakes En vi ro nm en ta l L ab or at or y Richard Kasul, Daniel Stynes, Lichu...Levels, and Associated Economic Impacts of Recreation at Bull Shoals, Norfork, and Table Rock Lakes Richard Kasul, Lichu Lee, R. Scott...This study provides a broadly scoped examination of park-based recreation at Bull Shoals, Norfork, and Table Rock Lakes, so that present and emerging

  14. Spatial synchrony in cisco recruitment

    USGS Publications Warehouse

    Myers, Jared T.; Yule, Daniel L.; Jones, Michael L.; Ahrenstorff, Tyler D.; Hrabik, Thomas R.; Claramunt, Randall M.; Ebener, Mark P.; Berglund, Eric K.

    2015-01-01

    We examined the spatial scale of recruitment variability for disparate cisco (Coregonus artedi) populations in the Great Lakes (n = 8) and Minnesota inland lakes (n = 4). We found that the scale of synchrony was approximately 400 km when all available data were utilized; much greater than the 50-km scale suggested for freshwater fish populations in an earlier global analysis. The presence of recruitment synchrony between Great Lakes and inland lake cisco populations supports the hypothesis that synchronicity is driven by climate and not dispersal. We also found synchrony in larval densities among three Lake Superior populations separated by 25–275 km, which further supports the hypothesis that broad-scale climatic factors are the cause of spatial synchrony. Among several candidate climate variables measured during the period of larval cisco emergence, maximum wind speeds exhibited the most similar spatial scale of synchrony to that observed for cisco. Other factors, such as average water temperatures, exhibited synchrony on broader spatial scales, which suggests they could also be contributing to recruitment synchrony. Our results provide evidence that abiotic factors can induce synchronous patterns of recruitment for populations of cisco inhabiting waters across a broad geographic range, and show that broad-scale synchrony of recruitment can occur in freshwater fish populations as well as those from marine systems.

  15. Habitat Suitability Index Models: Lake trout (exclusive of the Great Lakes)

    USGS Publications Warehouse

    Marcus, Michael D.; Hubert, Wayne A.; Anderson, Stanley H.

    1984-01-01

    The lake trout is an important commercial and sport fish in North America. In the Central Rocky Mountain regi on, 1ake trout are common ly referred to as "mackinaw". There is good evidence that lake trout should be called "1 ake charr" (Morton 1980). No subspecies of lake trout is presently recognized (Robins et al. 1980). The species, however, has extreme variability throughout its range, making it difficult to draw general conclusions about its biology (Martin and Olver 1980).

  16. Spatial and temporal movement dynamics of brook Salvelinus fontinalis and brown trout Salmo trutta

    USGS Publications Warehouse

    Davis, L.A.; Wagner, Tyler; Barton, Meredith L.

    2015-01-01

    Native eastern brook trout Salvelinus fontinalis and naturalized brown trout Salmo trutta occur sympatrically in many streams across the brook trout’s native range in the eastern United States. Understanding within- among-species variability in movement, including correlates of movement, has implications for management and conservation. We radio tracked 55 brook trout and 45 brown trout in five streams in a north-central Pennsylvania, USA watershed to quantify the movement of brook trout and brown trout during the fall and early winter to (1) evaluate the late-summer, early winter movement patterns of brook trout and brown trout, (2) determine correlates of movement and if movement patterns varied between brook trout and brown trout, and (3) evaluate genetic diversity of brook trout within and among study streams, and relate findings to telemetry-based observations of movement. Average total movement was greater for brown trout (mean ± SD = 2,924 ± 4,187 m) than for brook trout (mean ± SD = 1,769 ± 2,194 m). Although there was a large amount of among-fish variability in the movement of both species, the majority of movement coincided with the onset of the spawning season, and a threshold effect was detected between stream flow and movement: where movement increased abruptly for both species during positive flow events. Microsatellite analysis of brook trout revealed consistent findings to those found using radio-tracking, indicating a moderate to high degree of gene flow among brook trout populations. Seasonal movement patterns and the potential for relatively large movements of brook and brown trout highlight the importance of considering stream connectivity when restoring and protecting fish populations and their habitats.

  17. Natural or Artificial? Habitat-Use by the Bull Shark, Carcharhinus leucas

    PubMed Central

    Werry, Jonathan M.; Lee, Shing Y.; Lemckert, Charles J.; Otway, Nicholas M.

    2012-01-01

    Background Despite accelerated global population declines due to targeted and illegal fishing pressure for many top-level shark species, the impacts of coastal habitat modification have been largely overlooked. We present the first direct comparison of the use of natural versus artificial habitats for the bull shark, Carcharhinus leucas, an IUCN ‘Near-threatened’ species - one of the few truly euryhaline sharks that utilises natural rivers and estuaries as nursery grounds before migrating offshore as adults. Understanding the value of alternate artificial coastal habitats to the lifecycle of the bull shark is crucial for determining the impact of coastal development on this threatened but potentially dangerous species. Methodology/Findings We used longline surveys and long-term passive acoustic tracking of neonate and juvenile bull sharks to determine the ontogenetic value of natural and artificial habitats to bull sharks associated with the Nerang River and adjoining canals on the Gold Coast, Australia. Long-term movements of tagged sharks suggested a preference for the natural river over artificial habitat (canals). Neonates and juveniles spent the majority of their time in the upper tidal reaches of the Nerang River and undertook excursions into adjoining canals. Larger bull sharks ranged further and frequented the canals closer to the river mouth. Conclusions/Significance Our work suggests with increased destruction of natural habitats, artificial coastal habitat may become increasingly important to large juvenile bull sharks with associated risk of attack on humans. In this system, neonate and juvenile bull sharks utilised the natural and artificial habitats, but the latter was not the preferred habitat of neonates. The upper reaches of tidal rivers, often under significant modification pressure, serve as nursery sites for neonates. Analogous studies are needed in similar systems elsewhere to assess the spatial and temporal generality of this research

  18. Biochemical and organoleptic characteristics of muscle from early and late maturing bulls in different production systems.

    PubMed

    Mezgebo, G B; Monahan, F J; McGee, M; O'Riordan, E G; Picard, B; Richardson, R I; Moloney, A P

    2016-12-28

    In grass-based beef production systems (PS), early maturing (EM) breed types may be preferable to late maturing (LM) breed types in achieving adequate carcass fat cover. Biochemical and organoleptic characteristics of muscle from suckler bulls were investigated in EM and LM (n=28/breed) assigned to one of two PS (ad libitum concentrates and grass silage to slaughter (C) or ad libitum silage plus 2 kg concentrate daily during winter followed by 99 days at pasture and then an indoor finishing period on C (GSPC)) in a 2 breed type×2 PS factorial arrangement of treatments. Bulls were managed to have a common target carcass weight of 380 kg. Intramuscular fat (IMF) content was higher (P<0.05) for EM than LM, and for C than GSPC bulls. Collagen solubility was higher (P<0.05) for C than GSPC bulls. Lactate dehydrogenase (LDH) and phosphofructokinase activities were higher (P<0.05) for LM than EM. Isocitrate dehydrogenase activity and the Type I myosin heavy chain (MyHC) proportion were higher (P<0.05) for EM than LM. The LDH activity and the Type IIX MyHC proportion were higher (P<0.05) for C than GSPC bulls. Sensory ratings for tenderness and juiciness were higher (P<0.01) for beef from EM than LM while sensory ratings for tenderness, flavour liking and overall liking were higher (P<0.001) for C than for GSPC bulls. Differences in sensory quality were largely eliminated when adjusted for IMF. Overall, carcass fat scores, IMF and sensory scores were higher in EM than LM and in C than GSPC bulls but most differences in sensory quality could be attributed to differences in IMF.

  19. Evaluation of sperm DNA damage in bulls by TUNEL assay as a parameter of semen quality.

    PubMed

    Takeda, Kumiko; Uchiyama, Kyoko; Kinukawa, Masashi; Tagami, Takahiro; Kaneda, Masahiro; Watanabe, Shinya

    2015-01-01

    Sperm DNA damage affects the conception rate resulting from human assisted reproduction technology. The objective of this study was to adapt the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay to provide a quality parameter for bull semen based on the detection of sperm DNA damage. Fresh semen was collected from two Japanese Black bulls (A, B) several times over the course of a year, and the percentage of TUNEL-positive spermatozoa (sperm TUNEL index) was determined. Individual differences in semen were detected using the sperm TUNEL index in these bulls (P < 0.01). The sperm TUNEL index of cryopreserved semen obtained from test-mated Japanese Black (n = 30, including two bulls with a conception rate lower than 10%) and Holstein (n = 34) bulls were analyzed. The average sperm TUNEL index and conception rate resulting from artificial insemination (AI) were 4.7% and 55.7% for Japanese Black, and 4.9% and 39.5% for Holstein, respectively. A weak negative correlation between sperm TUNEL index and conception rate was observed in Holstein bulls (P < 0.05). Semen samples from six bulls with more than 10% sperm TUNEL index were studied, and these samples showed low sperm viability. However, semen resulting in a very low conception rate did not have a high sperm TUNEL index. Although it would be difficult to predict a low conception rate resulting from AI using the sperm TUNEL index alone, the index can be used as an additional parameter to provide a more comprehensive description of semen quality.

  20. Relationships among production traits and estimates of sex drive and dominance value in yearling beef bulls.

    PubMed

    Ologun, A G; Chenoweth, P J; Brinks, J S

    1981-04-01

    Average daily gain (ADG) and final test weight (FTW) were compared with libido score (L), serving capacity score (SC), reaction time to first mount (RTM), reaction time to first service (RTS) and dominance value (DV) in 90 purebred yearling beef bulls which had just completed an 140-day performance test. The bulls represented 15 breeding lines (12 Hereford, 2 Black Angus and 1 Red Angus) and nine sires within lines. Libido and serving capacity assessments were applied to randomly selected groups of two bulls which were tested for 10-minutes with nonestrous heifers restrained in service crates. RTM and RTS were recorded for both tests. Social dominance was assessed during randomized observations of social interactions between bulls within their pen groups (comprising 9 to 10 bulls) over four days. Two methods of determining social dominance (DV1 and DV2) were employed initially. Differences occurred among both lines and sire/lines in mean and best libido scores (P < .05). Sire/lines differed in L1, while both lines and sire/lines differed in L2 (P < .05). These differences were not reflected in either reaction times or serving capacity scores. Sires and sire/lines both differed in FTW (P < .05 and P < .01 respectively), while DV1 differed with sire/lines (P < .01). DV1 and DV2 were highly correlated (r = .84). Those sex-drive estimates which correlated with DV1 were the mean and best libido scores, mean serving capacity score, L2 and RTS 1 (P < .05). All correlations were negative, indicating that dominance and sex-drive may be unfavourably related in yearling beef bulls. ADG and FTW showed negative correlations with the mean and best serving capacity scores and with SC2 (P < .05). The only positive correlations between the two production traits and a sex-drive estimate was with RTM 2 (P < .05). This indicates that ADG and FTW may be unfavourably related to sex-drive in yearling beef bulls.

  1. Facilitating Alzheimer disease research recruitment.

    PubMed

    Grill, Joshua D; Galvin, James E

    2014-01-01

    Alzheimer disease (AD) research faces challenges to successful enrollment, especially to clinical trials and biomarker studies. Failure to recruit the planned number of participants in a timely manner threatens the internal validity and success of clinical research, raising concerns about external validity and generalizability of results, and possibly leading to disparities in disease treatment. Methods to improve recruitment exist, but require varying levels of staff effort and financial resources, and evidence of effectiveness is often lacking or inconsistent. In this review, we summarize some of the available methods to improve AD research recruitment, the available literature to support or refute these strategies, and some of the experiences at the authors' AD Research Centers. We discuss the use of community-based participatory research principles and participant registries as a means to enhance research enrollment and increase diversity of research samples.

  2. Promotion of Hepatocarcinogenesis by Perfluoroalkyl Acids in Rainbow Trout

    PubMed Central

    Benninghoff, Abby D.; Orner, Gayle A.; Buchner, Clarissa H.; Hendricks, Jerry D.; Duffy, Aaron M.; Williams, David E.

    2012-01-01

    Previously, we reported that perfluorooctanoic acid (PFOA) promotes liver cancer in a manner similar to that of 17β-estradiol (E2) in rainbow trout. Also, other perfluoroalkyl acids (PFAAs) are weakly estrogenic in trout and bind the trout liver estrogen receptor. The primary objective of this study was to determine whether multiple PFAAs enhance hepatic tumorigenesis in trout, an animal model that represents human insensitivity to peroxisome proliferation. A two-stage chemical carcinogenesis model was employed in trout to evaluate PFOA, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorooctane sulfonate (PFOS), and 8:2 fluorotelomer alcohol (8:2FtOH) as complete carcinogens or promoters of aflatoxin B1 (AFB1)- and/or N-methyl-N′-nitro-N-nitrosoguanidine (MNNG)-induced liver cancer. A custom trout DNA microarray was used to assess hepatic transcriptional response to these dietary treatments in comparison with E2 and the classic peroxisome proliferator, clofibrate (CLOF). Incidence, multiplicity, and size of liver tumors in trout fed diets containing E2, PFOA, PFNA, and PFDA were significantly higher compared with AFB1-initiated animals fed control diet, whereas PFOS caused a minor increase in liver tumor incidence. E2 and PFOA also enhanced MNNG-initiated hepatocarcinogenesis. Pearson correlation analyses, unsupervised hierarchical clustering, and principal components analyses showed that the hepatic gene expression profiles for E2 and PFOA, PFNA, PFDA, and PFOS were overall highly similar, though distinct patterns of gene expression were evident for each treatment, particularly for PFNA. Overall, these data suggest that multiple PFAAs can promote liver cancer and that the mechanism of promotion may be similar to that of E2. PMID:21984479

  3. Promotion of hepatocarcinogenesis by perfluoroalkyl acids in rainbow trout.

    PubMed

    Benninghoff, Abby D; Orner, Gayle A; Buchner, Clarissa H; Hendricks, Jerry D; Duffy, Aaron M; Williams, David E

    2012-01-01

    Previously, we reported that perfluorooctanoic acid (PFOA) promotes liver cancer in a manner similar to that of 17β-estradiol (E2) in rainbow trout. Also, other perfluoroalkyl acids (PFAAs) are weakly estrogenic in trout and bind the trout liver estrogen receptor. The primary objective of this study was to determine whether multiple PFAAs enhance hepatic tumorigenesis in trout, an animal model that represents human insensitivity to peroxisome proliferation. A two-stage chemical carcinogenesis model was employed in trout to evaluate PFOA, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorooctane sulfonate (PFOS), and 8:2 fluorotelomer alcohol (8:2FtOH) as complete carcinogens or promoters of aflatoxin B(1) (AFB(1))- and/or N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced liver cancer. A custom trout DNA microarray was used to assess hepatic transcriptional response to these dietary treatments in comparison with E2 and the classic peroxisome proliferator, clofibrate (CLOF). Incidence, multiplicity, and size of liver tumors in trout fed diets containing E2, PFOA, PFNA, and PFDA were significantly higher compared with AFB(1)-initiated animals fed control diet, whereas PFOS caused a minor increase in liver tumor incidence. E2 and PFOA also enhanced MNNG-initiated hepatocarcinogenesis. Pearson correlation analyses, unsupervised hierarchical clustering, and principal components analyses showed that the hepatic gene expression profiles for E2 and PFOA, PFNA, PFDA, and PFOS were overall highly similar, though distinct patterns of gene expression were evident for each treatment, particularly for PFNA. Overall, these data suggest that multiple PFAAs can promote liver cancer and that the mechanism of promotion may be similar to that of E2.

  4. Agonistic behavior among three stocked trout species in a novel reservoir fish community

    USGS Publications Warehouse

    Budy, Phaedra; Hafen, Konrad

    2015-01-01

    The popularity of reservoirs to support sport fisheries has led to the stocking of species that did not co-evolve, creating novel reservoir fish communities. In Utah, the Bear Lake strain of Bonneville Cutthroat Trout Oncorhynchus clarkii utah and tiger trout (female Brown Trout Salmo trutta × male Brook Trout Salvelinus fontinalis) are being more frequently added to a traditional stocking regimen consisting primarily of Rainbow TroutO. mykiss. Interactions between these three predatory species are not well understood, and studies evaluating community interactions have raised concern for an overall decrease of trout condition. To evaluate the potential for negative interactions among these species, we tested aggression in laboratory aquaria using three-species and pairwise combinations at three densities. Treatments were replicated before and after feeding. During the three-species trials Rainbow Trout initiated 24.8 times more aggressive interactions than Cutthroat Trout and 10.2 times more aggressive interactions than tiger trout, and tiger trout exhibited slightly (1.9 times) more aggressive initiations than Cutthroat Trout. There was no significant difference in behavior before versus after feeding for any species, and no indication of increased aggression at higher densities. Although Rainbow Trout in aquaria may benefit from their bold, aggressive behavior, given observations of decreased relative survival in the field, these benefits may be outweighed in reservoirs, possibly through unnecessary energy expenditure and exposure to predators.

  5. Estimate of net trophic transfer efficiency of PCBs to Lake Michigan lake trout from their prey

    USGS Publications Warehouse

    Madenjian, Charles P.; Hesselberg, Robert J.; DeSorcie, Timothy J.; Schmidt, Larry J.; Stedman, Ralph M.; Quintal, Richard T.; Begnoche, Linda J.; Passino-Reader, Dora R.

    1998-01-01

    Most of the polychlorinated biphenyl (PCB) body burden accumulated by lake trout (Salvelinus namaycush) from the Laurentian Great Lakes is from their food. We used diet information, PCB determinations in both lake trout and their prey, and bioenergetics modeling to estimate the efficiency with which Lake Michigan lake trout retain PCBs from their food. Our estimates were the most reliable estimates to date because (a) the lake trout and prey fish sampled during our study were all from the same vicinity of the lake, (b) detailed measurements were made on the PCB concentrations of both lake trout and prey fish over wide ranges in fish size, and (c) lake trout diet was analyzed in detail over a wide range of lake trout size. Our estimates of net trophic transfer efficiency of PCBs to lake trout from their prey averaged from 0.73 to 0.89 for lake trout between the ages of 5 and 10 years old. There was no evidence of an upward or downward trend in our estimates of net trophic transfer efficiency for lake trout between the ages of 5 and 10 years old, and therefore this efficiency appeared to be constant over the duration of the lake trout's adult life in the lake. On the basis of our estimtes, lake trout retained 80% of the PCBs that are contained within their food.

  6. Seasonal temperature and precipitation regulate brook trout young-of-the-year abundance and population dynamics

    USGS Publications Warehouse

    Kanno, Yoichiro; Pregler, Kasey C.; Hitt, Nathaniel P.; Letcher, Benjamin H.; Hocking, Daniel; Wofford, John E.B.

    2015-01-01

    Our results indicate that YOY abundance is a key driver of brook trout population dynamics that is mediated by seasonal weather patterns. A reliable assessment of climate change impacts on brook trout needs to account for how alternations in seasonal weather patterns impact YOY abundance and how such relationships may differ across the range of brook trout distribution.

  7. IN VIVO MEASUREMENT OF PHENYLGLUCUCURONIDE IN RAINBOW TROUT BY ON-LINE INJECTION MICRODIALYSIS

    EPA Science Inventory

    Phenylglucuronide (PG) was measured in vivo in arterial blood of rainbow trout using on-line injection microdialysis. A microdialysis probe was surgically implanted in the dorsal aorta of spinally-transected trout. The trout were dosed continuously with PG for 24 h using a ventra...

  8. Exploring trends, causes, and consequences of declining lipids in Lake Superior lake trout

    EPA Science Inventory

    The ability of lake trout to forage in deepwater habitats is facilitated by high lipid content, which affords buoyancy. In Lake Superior, lean lake trout historically occupied depths < 80 m, and siscowet lake trout occupied depths > 80 m. Siscowets have been known f...

  9. Introgression and susceptibility to disease in a wild population of rainbow trout

    USGS Publications Warehouse

    Currens, K.P.; Hemmingsen, A.R.; French, R.A.; Buchanan, D.V.; Schreck, C.B.; Li, H.W.

    1997-01-01

    We examined susceptibility of wild rainbow trout Oncorhynchus mykiss from the Metolius River, a tributary of the Deschutes River, Oregon, to genetic introgression and ceratomyxosis as a result of stocking nonnative hatchery rainbow trout. Ceratomyxa shasta, an enzootic myxosporean parasite that can be lethal to nonnative hatchery rainbow trout, might have been limiting the interbreeding of hatchery and wild rainbow trout in the river. However, rainbow trout from the Metolius River had allozyme frequencies intermediate between those of wild and hatchery fish at LDH-B2* and sSOD-1*, two diagnostic genetic loci that allow the inland subspecies of rainbow trout to be distinguished from hatchery strains of coastal origin. They also had notable frequencies of ADA-1*85, an allele documented in hatchery rainbow trout but rarely seen in wild populations. We also found that rainbow trout in the Metolius River averaged 138.9 scales in the lateral series, intermediate between the counts for 9 coastal or nonnative hatchery populations, which always had fewer than 140 scales, and 10 inland populations, which always had more than 140 scales. Disease challenges revealed that rainbow trout from the Metolius River had much greater susceptibility to C. shasta than rainbow trout from the Deschutes River, which have genetic resistance to the lethal disease. Based on these data, we concluded that introgression with nonnative hatchery rainbow trout has reduced the abilities of wild rainbow trout in the Metolius River to survive when conditions for ceratomyxosis infection occur.

  10. Nucléation, ascension et éclatement d'une bulle de champagne

    NASA Astrophysics Data System (ADS)

    Liger-Belair, G.

    2006-03-01

    People have long been fascinated by bubbles and foams dynamics, and since the pioneering work of Leonardo da Vinci in the early 16th century, this subject has generated a huge bibliography. However, only quite recently, much interest was devoted to bubbles in Champagne wines and carbonated beverages. Since the time of the benedictine monk dom Pierre Perignon (1638-1715), champagne is the wine of celebration. This fame is largely linked to the elegance of its effervescence and foaming properties. In this book, the latest results about the chemical physics behind the bubbling properties of Champagne and sparkling wines are collected and fully illustrated. The first chapter is devoted to the history of champagne and to a presentation of the tools of the physical chemistry of interfaces needed for a whole comprehension of the book. Then, the three main steps of a fleeting champagne bubble's life are presented in chronological order, that is, the bubble nucleation on the glass wall (Chap.2), the bubble ascent and growth through the liquid matrix (Chap.3), and the bursting of bubbles at the liquid surface (Chap.4), which constitutes the most intriguing, functional, and visually appealing step. L'objectif général de ce travail consacré à l'étude des processus physicochimiques liés à l'effervescence des vins de Champagne était de décortiquer les différentes étapes de la vie d'une bulle de champagne en conditions réelles de consommation, dans une flûte. Nous résumons ci-après les principaux résultats obtenus pour chacune des étapes de la vie de la bulle, depuis sa naissance sur les parois d'une flûte, jusqu'à son éclatement en surface. Nucléation À l'aide d'une caméra rapide munie d'un objectif de microscope, nous avons pu mettre à mal une idée largement répandue. Ce ne sont pas les anfractuosités de la surface du verre ou de la flûte qui sont responsable de la nucléation hétérogène des bulles, mais des particules adsorbées sur les parois du

  11. 77 FR 62500 - Peabody Trout Creek Reservoir LLC; Notice of Intent To File License Application, Filing of Pre...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-15

    ... Energy Regulatory Commission Peabody Trout Creek Reservoir LLC; Notice of Intent To File License...: Peabody Trout Creek Reservoir LLC. e. Name of Project: Trout Creek Reservoir Hydroelectric Project. f... Preservation at 36 CFR 800.2. l. With this notice, we are designating Peabody Trout Creek Reservoir LLC as...

  12. Effects of dietary energy on sexual maturation and sperm production in Holstein bulls.

    PubMed

    Harstine, B R; Maquivar, M; Helser, L A; Utt, M D; Premanandan, C; DeJarnette, J M; Day, M L

    2015-06-01

    In prepubertal bulls and heifers of dairy and beef breeds, puberty can be induced to occur earlier than typical with targeted high-energy diets due to precocious activation of the endocrine mechanisms that regulate puberty. Precocious activation of puberty in bulls intended for use in the AI industry has the potential to hasten and perhaps increase sperm production. It was hypothesized that feeding bulls a high-energy diet beginning at 8 wk of age would advance the prepubertal rise in LH and lead to advanced testicular maturation and age at puberty. From 58 to 230 ± 0.3 d of age, Holstein bulls received either a high-energy diet (HE;n = 9; targeted ADG 1.5 kg/d) or a control diet (CONT;n = 10; targeted ADG 0.75 kg/d). Thereafter, all bulls were fed a similar diet. The HE treatment increased LH secretion at 125 d of age, testosterone concentrations from 181 to 210 d, and scrotal circumference (SC) from 146 to 360 d of age relative to the CONT treatment. Beginning at 241 ± 5 d of age, semen collection (artificial vagina) was attempted every 14 d in bulls from the HE (n = 8) and CONT (n = 7) treatment until each bull attained puberty (ejaculate containing 50 × 10 spermatozoa with 10% motility). To assess semen production as mature bulls, semen was collected thrice weekly beginning at 541 ± 5 d of age until slaughter at 569 ± 5 d of age. After slaughter, epididymal and testicular measurements were collected and testicular tissue was fixed to determine seminiferous tubule diameter. Age at puberty did not differ between treatments (310 ± 35 d). Although testis and epididymal weight and testis volume were greater (P < 0.05) in the HE than the CONT treatment, sperm production of mature bulls did not differ between treatments. Diameter of seminiferous tubules also did not differ between treatments. We conclude that the HE advanced aspects of sexual maturation and increased testes size, but this was not reflected in hastened puberty or sperm production in the present

  13. Glacial oceanographic contrasts explain phylogeography of Australian bull kelp.

    PubMed

    Fraser, Ceridwen I; Spencer, Hamish G; Waters, Jonathan M

    2009-05-01

    The evolutionary effects of Southern Hemisphere Pleistocene oceanographic conditions - marked by fluctuations in sea levels and water temperatures, and redirected currents - are poorly understood. The southeastern tip of Australia presents an intriguing model system for studying the biological impacts of palaeoceanography. In particular, contrasting oceanographic conditions that existed on eastern vs. western sides of the Bassian Isthmus during Pleistocene glacial periods allow for natural comparisons between putative refugial vs. re-invading populations. Whereas many western Tasmanian marine taxa were likely eliminated by cold subantarctic water during the last glacial period, eastern Tasmanian populations would have persisted in relatively warm temperatures mediated by the ongoing influence of the East Australian Current (EAC). Here we test for the effects of contrasting palaeoceanographic conditions on endemic bull kelp, Durvillaea potatorum, using DNA sequence analysis (COI; rbcL) of more than 100 individuals from 14 localities in southeastern Australia. Phylogenetic reconstructions reveal a deep (maximum divergence 4.7%) genetic split within D. potatorum, corresponding to the 'eastern' and 'western' geographical regions delimited by the Bassian Isthmus, a vicariant barrier during low Pleistocene sea levels. Concordant with the western region's cold glacial conditions, samples from western Tasmania and western Victoria are genetically monomorphic, suggesting postglacial expansion from a mainland refugium. Eastern samples, in contrast, comprise distinct regional haplogroups, suggesting the species persisted in eastern Tasmania throughout recent glacial periods. The deep east-west divergence seems consistent with earlier reports of morphological differences between 'western' and 'eastern' D. potatorum, and it seems likely that these forms represent reproductively isolated species.

  14. International Student Recruitment: Trends and Challenges

    ERIC Educational Resources Information Center

    Falcone, Santa

    2017-01-01

    This paper provides a review of current trends in international student recruitment. Focusing specifically on recruitment of Chinese students, important aspects of China's educational system relevant to recruitment are presented. Barriers to Chinese student recruitment are then discussed. Successful, employed, international graduates validate…

  15. Ruptured urinary bladder attributable to urethral compression by a haematoma after vertebral fracture in a bull

    PubMed Central

    2014-01-01

    Background In male cattle, rupture of the urinary bladder is usually associated with urethral obstruction by uroliths. Less common causes include urethral compression or stricture. This case report describes the findings in a young Limousion breeding bull with rupture of the urinary bladder because of urethral compression by a haematoma after coccygeal fracture. Case presentation The bull had been introduced into a 40-head Red-Holstein herd one week before being injured. One week after introduction to the herd, the bull had an acute onset of anorexia and he was referred to the clinic. There was marked abdominal distension, reduced skin turgor and enophthalmus. The serum concentration of urea and creatinine was increased. Ultrasonographic examination revealed severe ascites and abdominocentesis yielded clear yellow fluid with high urea and creatinine concentrations, which supported a diagnosis of uroperitoneum. The bull was euthanatized because of a poor prognosis. Postmortem examination revealed a comminuted fracture of the first two coccygeal vertebrae associated with a massive haematoma that obstructed entire pelvic cavity. The haematoma compressed the urethra thereby preventing outflow of urine, which resulted in a 5-cm tear ventrally at the neck of the bladder. It was assumed that the newly-introduced bull had sustained the vertebral fractures when he was mounted by a cow. Conclusions The present case study serves to expand the differential diagnosis of urinary bladder rupture. Therefore, in addition to obstructive urolithiasis, compression and stricture of the urethra might be considered in male cattle with uroperitoneum. PMID:24666697

  16. Effects of GnRH treatment on scrotal surface temperatures in bulls.

    PubMed Central

    Gábor, G; Kastelic, J P; Cook, R B; Sasser, R G; Brito, L F; Csik, J V; Coulter, G H; Györkös, I

    2001-01-01

    Two experiments were conducted to characterize scrotal surface temperature (SST) in bulls treated with gonadotropin releasing hormone (GnRH). In Experiment 1, Angus bulls (n = 10, 18 mo, 597 kg) were given GnRH (400 ng/kg) or saline, IV. Bottom SST increased approximately 1.7 degrees C (P < 0.005) over time (0 to 90 min) at an ambient temperature of 5 degrees C. However, there was no significant effect of GnRH treatment and temperature increases were attributed to stress. When the experiment was repeated at an ambient temperature of 25 degrees C, SST was elevated prior to treatment, with no subsequent significant increase. Experiment 2 was conducted with Charolais bulls (n = 6, 12-14 mo, 517 kg) with an emphasis on minimizing stress. Bottom SST increased approximately 2 degrees C (P < 0.05) between 0 and 45 min after GnRH treatment, supporting the hypothesis that GnRH treatment increases SST in bulls. In conclusion, it was apparent that stress, high ambient temperatures, and GnRH treatment can all increase SST in bulls. PMID:11227197

  17. Prevention of dark-cutting (DFD) beef in penned bulls at the abattoir.

    PubMed

    Bartoš, L; Franc, C; Albiston, G; Beber, K

    1988-01-01

    There is a large body of evidence indicating that activities associated with regrouping of bulls before slaughter, which leads to physical exhaustion mainly from mounting, are primary factors inducing dark-cutting (DFD) in beef. The aim of this study was to test several methods to control activity when regrouping cannot be avoided. Fifty bulls previously individually tied for at least 16 months were drafted into groups of five animals and released in a pen at the abattoir. After 18 to 22 h they were slaughtered. According to environmental conditions in the pen, the bulls were divided into four groups: Control group (n = 10, no experimentation); Electricity group (n = 10, an electric fence was constructed above the pen so that a mounting bull would receive an electric shock); Darkness group (n = 10, the whole stall was in darkness); and Combination group (n = 20, both treatments, of the electricity and darkness groups were applied). During the first hour of penning the behaviour of the bulls was videorecorded. After slaughter meat quality characteristics were measured. Dark-cutting was found in Control (70%), Electricity (30%) and Darkness (70%) groups, but not in the Combination group (0%). No treatment altered the repertoire of agonistic activity, but under the combined treatments the number of agonistic interactions was significantly lower than in any other group.

  18. Growth hormone treatment of breeding bulls used for artificial insemination improves fertilization rates.

    PubMed

    Sauerwein, H; Breier, B H; Gallaher, B W; Götz, C; Küfner, G; Montag, T; Vickers, M; Schallenberger, E

    2000-01-01

    To evaluate new therapeutical concepts for male subfertility, we tested the effects of exogenous recombinant bovine growth hormone (rbGH) on various endocrine and metabolic parameters both in blood and in seminal plasma of bulls. Sperm quality was assessed morphometrically and by monitoring the number of successful artificial inseminations (AIs) defined as non-return rates (NRR). Aliquots of 450 semen samples were used from each bull and each experimental period (4 wk before, 14 weeks during and 6 wk after treatment). Six out of ten sires (average age 8.4 years) were treated every two weeks with 640-mg depot formulated rbGH (Eli Lilly). Four bulls received vehicle only. Blood plasma bGH, IGF-I, insulin and glucose concentrations were increased with rbGH treatment. In seminal plasma there was no effect of rbGH treatment on fructose and citrate or on testosterone concentrations. With one exception, rbGH-treated bulls had greater IGFBP-3 concentrations in seminal plasma. Motility of spermatozoa after freezing and thawing was increased compared with pretreatment rates. Most interestingly, the number of successful AIs was increased by an average of 6.0% NRR when ejaculates from rbGH-treated bulls were used.

  19. Collection of preputial material by scraping and aspiration for the diagnosis of Tritrichomonas foetus in bulls.

    PubMed

    Irons, P C; Henton, M M; Bertschinger, H J

    2002-06-01

    Two trials were carried out to assess the diagnostic sensitivity and practicability of preputial scraping as a method of collecting preputial material from bulls infected with Tritrichomonas foetus. In the 1st trial, preputial material was collected by simultaneous scraping and aspiration from 3 infected and 1 uninfected bull 10 times over a 5-week period. In the 2nd trial, samples from 5 infected bulls were collected by both sheath washing and scraping on 6 occasions, while 8 uninfected animals were sampled 3 times. Samples were cultured using a modified Trichomonas culture medium (Oxoid). In the first trial, 29 of 30 samples from infected bulls were found to be positive. In the second trial, 83 % of samples collected by both methods tested positive. In neither trial were any samples from the control bulls found to be positive. Scraping was found to be quick and safe, and offered advantages over preputial washing in that urine contamination was easily avoided, samples were smaller and more concentrated and contamination was reduced. It may, however, be subject to greater operator variability than sheath washing. It is concluded that preputial scraping is as effective as washing and represents a suitable alternative for the collection of material for direct examination and culture of Tritrichomonas foetus.

  20. Recruiting Trends, 2008-2009

    ERIC Educational Resources Information Center

    Collegiate Employment Research Institute (NJ3), 2009

    2009-01-01

    This paper presents the recruiting trends for 2008-2009. This year's report is based on 945 respondents, including 57 K-12 schools. The researchers continued their focus on fast-growth small companies and expended most of their energy in retaining their sample distribution, knowing that the prevailing economic situation would reduce responses.…

  1. Ethical Issues in Recruiting Students.

    ERIC Educational Resources Information Center

    Fiske, Edward B.

    1981-01-01

    Examples of deceptive recruitment are highlighted in a review of questionable practices used to attract students both from within the United States and abroad. Major issues for action are identified as sacrificing quality for numbers, the hiring of marketing consultants, professional training of admissions directors, and federal regulation.…

  2. Recruiting Trends, 2006-2007

    ERIC Educational Resources Information Center

    Collegiate Employment Research Institute (NJ3), 2007

    2007-01-01

    College students who plan on entering the labor market can expect to see more job opportunities in the spring of 2007, according to information supplied by 864 companies and organizations to this year's Recruiting Trends Report. After two years of double digit growth, the expansion will slow to a modest 4% to 6%. Two opposing factors appear to be…

  3. Building a Winning Recruiting Team.

    ERIC Educational Resources Information Center

    Taguchi, Sherrie Gong

    2002-01-01

    Building a winning recruiting team is essential to the well being of virtually every organization. Putting together a great mix of people to represent an organization and bring in new talent can serve an organization well when competition is fierce or demand is down. (GCP)

  4. Recruiting Trends, 2005-2006

    ERIC Educational Resources Information Center

    Collegiate Employment Research Institute (NJ3), 2006

    2006-01-01

    Almost 900 employers responded to this year's "Recruiting Trends" survey, the largest response in the history of this project. Hiring of college graduates is expected to increase by single digits minimally, or double digits if certain geographic sectors are excluded (between 6% and 14%). This growth follows a robust 20% increase in…

  5. Recruiting Trends, 2007-2008

    ERIC Educational Resources Information Center

    Collegiate Employment Research Institute (NJ3), 2008

    2008-01-01

    This paper presents the recruiting trends for 2007-2008. This year's report is based on 994 respondents, including 84 K-12 school districts. The researchers focused attention on growing companies, based on lists from Forbes and Inc. magazines, and as a result, they have more small and medium-size employers represented this year. The sample…

  6. Three Recruitment and Retention Surveys.

    ERIC Educational Resources Information Center

    Bronx Community Coll., NY.

    This three-part report summarizes methodology and findings of three recruitment and retention studies conducted by the Bronx Community College (BCC) during 1979-1980. Part I examines a survey of enrolled students conducted to determine student attitudes toward BCC, the services that were most in demand, the reasons for attending BCC, and student…

  7. [Utility of recruitment maneuvers (pro)].

    PubMed

    Suárez Sipmann, F

    2009-04-01

    In recent years lung recruitment maneuvers (RM) have awakened an increasing interest due to their potential beneficial effects in lung protection so that they have been progressively introduced into clinical practice. Many clinical and experimental studies have described the physiological benefits obtained after lung re-expansion although these benefits are not uniform, partly because of the wide heterogeneity of the RMs applied and lack of criteria defining their goal. Therefore, to date it has been difficult to establish the role of recruitment in the ventilatory management of ARDS patients. However, the information obtained from recent studies has improved our understanding regarding the mechanisms governing lung recruitment, interpretation of its response and its side effects and this has strongly contributed to its improved practical application. Lung recruitment must be applied in a protocolized and individualized way, establishing the pressure necessary to obtain the reasonably possible maximum lung re-expansion in each patient. Post RM PEEP adjustment is an essential aspect which, if ignored, renders RM useless and possibly without indication. Taking these essential aspects into account we are getting closer to, as the author believes, finally demonstrating the benefit of RM in lung protection and ARDS patients' outcome.

  8. Recruiting and Retaining Adult Students.

    ERIC Educational Resources Information Center

    Hadfield, Janice

    2003-01-01

    Adult learners, long the stepchildren of colleges and universities, have nearly become the norm, and they spend billions of dollars each year on education. This chapter takes a customer-oriented approach to recruiting and retaining adult students in higher education. (GCP)

  9. Recruiting Trends, 2009-2010

    ERIC Educational Resources Information Center

    Collegiate Employment Research Institute (NJ3), 2010

    2010-01-01

    This paper presents the recruiting trends for 2009-2010. This year's report is based on over 2,500 respondents, of which approximately 2,259 provided useable information with 1,846 including complete hiring figures used for the projections. The researchers continued their focus on fast-growth companies and expanded their efforts to ensure a…

  10. Marketer's forgotten challenge: physician recruitment.

    PubMed

    Plank, D

    1997-01-01

    As marketing department missions continue to expand, more and more people are finding themselves not just recruiting customers, but doctors. The good news: May of the tips and tricks of direct marketing can be used to reach out to in-demand physicians.

  11. Recruiting and Retaining Summer Staff.

    ERIC Educational Resources Information Center

    Crossen, Brian; Yerkes, Rita

    1998-01-01

    Recruiting of camp staff is challenged by economic and workplace restructuring, including business downsizing, part-time and temporary employment patterns, and generational attitude changes. Strategies for hiring and retaining staff include knowing what college-age workers want, marketing benefits, adopting new business strategies, and empowering…

  12. Evaluation of an Unsuccessful Brook Trout Electrofishing Removal Project in a Small Rocky Mountain Stream.

    SciTech Connect

    Meyer, Kevin A.; Lamansky, Jr., James A.; Schill, Daniel J.

    2006-01-26

    In the western United States, exotic brook trout Salvelinus fontinalis frequently have a deleterious effect on native salmonids, and biologists often attempt to remove brook trout from streams by means of electrofishing. Although the success of such projects typically is low, few studies have assessed the un