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• 1. [Article] Proceedings of the Wild Trout - Catchable Trout Symposium

  Abstract -- None

  Citation × Citation Citation Abstract Copy Title: Proceedings of the Wild Trout - Catchable Trout Symposium Abstract -- None Title: Proceedings of the Wild Trout - Catchable Trout Symposium Abstract -- None Close

• 2. [Article] NF - Effect of Bull Trout and Brook Trout Interactions on Foraging Habitat, Feeding Behavior, and Growth

  Abstract -- Observations of free-ranging sympatric bull trout Salvelinus confluentus and nonnative brook trout S. fontinalis in two eastern Oregon headwater streams provided little evidence of habitat ...

  Citation × Citation Citation Abstract Copy Title: NF - Effect of Bull Trout and Brook Trout Interactions on Foraging Habitat, Feeding Behavior, and Growth Abstract -- Observations of free-ranging sympatric bull trout Salvelinus confluentus and nonnative brook trout S. fontinalis in two eastern Oregon headwater streams provided little evidence of habitat partitioning. Both species held focal feeding points in similar microhabitats and fed primarily from the water column rather than from the surface or benthos. In an instream experiment, 20 enclosures were assigned one of three treatments: two bull trout, four bull trout, or a mix of two bull trout and two brook trout. In the enclosures, macroinvertebrate drift was restricted and trout densities were elevated, creating an environment of reduced food and habitat resources. Under these conditions, there was no indication of a niche shift by bull trout; feeding behavior and habitat use by bull trout did not differ depending on the presence or absence of brook trout. Brook trout in the mixed-species treatment were the most aggressive, maintained dominance in 75% of the enclosures, and exhibited significantly higher growth than sympatric bull trout. However, the effects of intra-and interspecific interactions on bull trout growth were equivalent. Given the absence of resource partitioning and a niche shift by bull trout in the presence of brook trout (despite obvious interference interactions), we suggest that the displacement of bull trout by brook trout is likely when resources are scarce. Title: NF - Effect of Bull Trout and Brook Trout Interactions on Foraging Habitat, Feeding Behavior, and Growth Abstract -- Observations of free-ranging sympatric bull trout Salvelinus confluentus and nonnative brook trout S. fontinalis in two eastern Oregon headwater streams provided little evidence of habitat partitioning. Both species held focal feeding points in similar microhabitats and fed primarily from the water column rather than from the surface or benthos. In an instream experiment, 20 enclosures were assigned one of three treatments: two bull trout, four bull trout, or a mix of two bull trout and two brook trout. In the enclosures, macroinvertebrate drift was restricted and trout densities were elevated, creating an environment of reduced food and habitat resources. Under these conditions, there was no indication of a niche shift by bull trout; feeding behavior and habitat use by bull trout did not differ depending on the presence or absence of brook trout. Brook trout in the mixed-species treatment were the most aggressive, maintained dominance in 75% of the enclosures, and exhibited significantly higher growth than sympatric bull trout. However, the effects of intra-and interspecific interactions on bull trout growth were equivalent. Given the absence of resource partitioning and a niche shift by bull trout in the presence of brook trout (despite obvious interference interactions), we suggest that the displacement of bull trout by brook trout is likely when resources are scarce. Close

• 3. [Article] Feeding behavior and diet of native bull trout Salvelinus confluentus and introduced brook trout S. fontinalis in two Eastern Oregon streams

  One of the greatest threats to native bull trout Salvelinus confluentus populations is the presence of non-native brook trout S. fontinalis. This study, conducted in two second-order Eastern Oregon streams, ...

  Citation × Citation Citation Abstract Copy Title: Feeding behavior and diet of native bull trout Salvelinus confluentus and introduced brook trout S. fontinalis in two Eastern Oregon streams Author: Gunckel, Stephanie L. One of the greatest threats to native bull trout Salvelinus confluentus populations is the presence of non-native brook trout S. fontinalis. This study, conducted in two second-order Eastern Oregon streams, investigates the effect of brook trout on the feeding behavior arid diet of bull trout. Feeding behavior, microhabitat use, and agonistic interactions were examined in a controlled in-stream experiment where twenty enclosures were randomly assigned one of three treatments: two bull trout, four bull trout, or a mix of two bull trout and two brook trout. Results provide little evidence of a niche shift for bull trout in the presence of brook trout or of resource partitioning between sympatric bull trout and brook trout. All fish held focal feeding points in similar microhabitats and fed primarily from the water column. Brook trout showed the greatest growth, were highly aggressive, and consistently dominated bull trout of equal size. Examination of stomach contents revealed allopatric bull trout, sympatric bull and brook trout fed primarily on larvae of Ephemeroptera, Trichoptera, and aquatic Diptera and terrestrial insects. Sympatric bull trout and brook trout had a high degree of dietary overlap. All fish exhibited size selective predation, and piscivory was rare. Similar habitat use, feeding behavior and diet of bull trout and brook trout, and aggressive interactions between these species suggest that, when habitat and prey resources are scarce, direct interference competition is likely, and the dominant behavior of brook trout may potentially displace bull trout. Title: Feeding behavior and diet of native bull trout Salvelinus confluentus and introduced brook trout S. fontinalis in two Eastern Oregon streams Author: Gunckel, Stephanie L. One of the greatest threats to native bull trout Salvelinus confluentus populations is the presence of non-native brook trout S. fontinalis. This study, conducted in two second-order Eastern Oregon streams, investigates the effect of brook trout on the feeding behavior arid diet of bull trout. Feeding behavior, microhabitat use, and agonistic interactions were examined in a controlled in-stream experiment where twenty enclosures were randomly assigned one of three treatments: two bull trout, four bull trout, or a mix of two bull trout and two brook trout. Results provide little evidence of a niche shift for bull trout in the presence of brook trout or of resource partitioning between sympatric bull trout and brook trout. All fish held focal feeding points in similar microhabitats and fed primarily from the water column. Brook trout showed the greatest growth, were highly aggressive, and consistently dominated bull trout of equal size. Examination of stomach contents revealed allopatric bull trout, sympatric bull and brook trout fed primarily on larvae of Ephemeroptera, Trichoptera, and aquatic Diptera and terrestrial insects. Sympatric bull trout and brook trout had a high degree of dietary overlap. All fish exhibited size selective predation, and piscivory was rare. Similar habitat use, feeding behavior and diet of bull trout and brook trout, and aggressive interactions between these species suggest that, when habitat and prey resources are scarce, direct interference competition is likely, and the dominant behavior of brook trout may potentially displace bull trout. Close

• 4. [Article] Distribution and habitat use of bull trout following the removal of nonnative brook trout

  Invasion by nonnative brook trout (Salvelinus fontinalis) often results in replacement of bull trout (Salvelinus confluentus) in western North America, but the causal mechanisms are not well understood. ...

  Citation × Citation Citation Abstract Copy Title: Distribution and habitat use of bull trout following the removal of nonnative brook trout Author: Renner, Dirk Invasion by nonnative brook trout (Salvelinus fontinalis) often results in replacement of bull trout (Salvelinus confluentus) in western North America, but the causal mechanisms are not well understood. Removal of brook trout from 1992 to 2000 from Sun Creek in southern Oregon, provided an opportunity to investigate the changes in distribution and abundance of bull trout. This study investigated bull trout distribution over from 1994 to 2003, during and following the extirpation of brook trout in 2000. In 2001 over, 8 km of contiguous stream habitat was examined to investigate bull trout habitat utilization. Bull trout abundance increased almost 300% after the removal of brook trout; however, bull trout distribution did not shift either upstream or downstream into habitat previously occupied by brook trout. This finding suggested that the occupied habitat was either critical for bull trout persistence or that factors restricted dispersal. Temperature did not appear to limit bull trout distribution remaining below 17°C with averages less than 10°C throughout Sun Creek. The downstream distribution of bull trout coincided with a point source increase of turbidity. In regions of the stream where turbidity was low bull trout abundance was positively associated with deep pools, higher average temperatures, and correlated with high densities of springs. The results of this study suggest that brook trout did not displace bull trout, underscoring the importance that point source disturbances (i.e. turbidity) can have on trout distributions. These findings reiterate the value of sampling contiguous streams as a means to identifying factors influencing trout distribution throughout a stream system. Title: Distribution and habitat use of bull trout following the removal of nonnative brook trout Author: Renner, Dirk Invasion by nonnative brook trout (Salvelinus fontinalis) often results in replacement of bull trout (Salvelinus confluentus) in western North America, but the causal mechanisms are not well understood. Removal of brook trout from 1992 to 2000 from Sun Creek in southern Oregon, provided an opportunity to investigate the changes in distribution and abundance of bull trout. This study investigated bull trout distribution over from 1994 to 2003, during and following the extirpation of brook trout in 2000. In 2001 over, 8 km of contiguous stream habitat was examined to investigate bull trout habitat utilization. Bull trout abundance increased almost 300% after the removal of brook trout; however, bull trout distribution did not shift either upstream or downstream into habitat previously occupied by brook trout. This finding suggested that the occupied habitat was either critical for bull trout persistence or that factors restricted dispersal. Temperature did not appear to limit bull trout distribution remaining below 17°C with averages less than 10°C throughout Sun Creek. The downstream distribution of bull trout coincided with a point source increase of turbidity. In regions of the stream where turbidity was low bull trout abundance was positively associated with deep pools, higher average temperatures, and correlated with high densities of springs. The results of this study suggest that brook trout did not displace bull trout, underscoring the importance that point source disturbances (i.e. turbidity) can have on trout distributions. These findings reiterate the value of sampling contiguous streams as a means to identifying factors influencing trout distribution throughout a stream system. Close

• 5. [Article] Threemile Creek Bull Trout Protection Final Report 1998

  Abstract -- Brook Trout were removed from Threemile Creek by electrofishing and night-snorkel spear-fishing. Electrofishing removal was conducted on 11 reaches and a total of 45 passes were completed. ...

  Citation × Citation Citation Abstract Copy Title: Threemile Creek Bull Trout Protection Final Report 1998 Abstract -- Brook Trout were removed from Threemile Creek by electrofishing and night-snorkel spear-fishing. Electrofishing removal was conducted on 11 reaches and a total of 45 passes were completed. Fifty brook trout were removed. Night-snorkeling was conducted in the five reach, intergrade zone where both bull and brook trout were found. Two comprehenzive passes were completed in the first three reaches, and three passes were completed in the last two reaches. A total of 10 brook trout and 8 brook/bull trout hybrids were removed. Additionally 39 brook trout were removed from a fire pond above Threemile Creek. Mollusk and amphibian surveys were also conducted; and temperature was collected in the Threemile Creek Project Area. Title: Threemile Creek Bull Trout Protection Final Report 1998 Abstract -- Brook Trout were removed from Threemile Creek by electrofishing and night-snorkel spear-fishing. Electrofishing removal was conducted on 11 reaches and a total of 45 passes were completed. Fifty brook trout were removed. Night-snorkeling was conducted in the five reach, intergrade zone where both bull and brook trout were found. Two comprehenzive passes were completed in the first three reaches, and three passes were completed in the last two reaches. A total of 10 brook trout and 8 brook/bull trout hybrids were removed. Additionally 39 brook trout were removed from a fire pond above Threemile Creek. Mollusk and amphibian surveys were also conducted; and temperature was collected in the Threemile Creek Project Area. Close

• 6. [Article] Threemile Creek Bull Trout Protection, 1997 Final Report (OWEB #97-112-007)

  Abstract -- Brook trout removal activities were conducted on Threemile Creek beginning in late June, and ending in late September 1997. Removal efforts consisted of electrofishing in the brook trout zone ...

  Citation × Citation Citation Abstract Copy Title: Threemile Creek Bull Trout Protection, 1997 Final Report (OWEB #97-112-007) Abstract -- Brook trout removal activities were conducted on Threemile Creek beginning in late June, and ending in late September 1997. Removal efforts consisted of electrofishing in the brook trout zone and night snorkel spearing in the bull trout intergrade zone (both brook trout and bull trout present). A total of 121 brook trout and one hybrid were removed by electrofishing. Of the 121 brook trout removed, 92 were greater than 90 mm in length. During night snorkel spearing 10 brook trout and 8 hybrids were removed and a total of 54 bull trout were observed. Macroinvertebrate and amphibian surveys were conducted in early September, and temparature was monitored throughout the project area. Experimental trapping was conducted, but no fish were collected during any trapping effort. Title: Threemile Creek Bull Trout Protection, 1997 Final Report (OWEB #97-112-007) Abstract -- Brook trout removal activities were conducted on Threemile Creek beginning in late June, and ending in late September 1997. Removal efforts consisted of electrofishing in the brook trout zone and night snorkel spearing in the bull trout intergrade zone (both brook trout and bull trout present). A total of 121 brook trout and one hybrid were removed by electrofishing. Of the 121 brook trout removed, 92 were greater than 90 mm in length. During night snorkel spearing 10 brook trout and 8 hybrids were removed and a total of 54 bull trout were observed. Macroinvertebrate and amphibian surveys were conducted in early September, and temparature was monitored throughout the project area. Experimental trapping was conducted, but no fish were collected during any trapping effort. Close

• 7. [Article] Oregon's Trout Plan: A Plan for the Management of Oregon's Trout 1987

  Abstract -- The Statewide Trout Management Plan is part of the Oregon Department of Fish and Wildlife's (ODFW) planning program to provide a comprehensive, systematic, long-term approach to the management ...

  Citation × Citation Citation Abstract Copy Title: Oregon's Trout Plan: A Plan for the Management of Oregon's Trout 1987 Abstract -- The Statewide Trout Management Plan is part of the Oregon Department of Fish and Wildlife's (ODFW) planning program to provide a comprehensive, systematic, long-term approach to the management of Oregon's fish resources. The Plan contains specific goals, objectives, strategies, and guidelines for the statewide management of trout, which are based on state laws, as well as general goals and policies adopted by the Oregon Fish and Wildlife Commission, (hereafter referred to as the Commission). In turn, the Plan provides direction for basin, subbasin, and mini plans developed for individual rivers and water bodies. The relationship of the Statewide Trout Management Plan to other ODFW plans is further discussed in Appendix A. This Statewide Management Plan will direct future trout management and will be reviewed in 6 years. The plan contains brief descriptions of Oregon's trout waters, species, anglers, and economic consequences. The importance of habitat and the use of angling regulations are also discussed. The plan covers all species of native and introduced resident trout and Pacific salmon that are managed in the resident trout program (Atlantic salmon, kokanee, coho salmon, and Chinook salmon) and the anadromous form (searun) of cutthroat trout. Appendix B contains a complete list of fish treated as trout in the plan. Title: Oregon's Trout Plan: A Plan for the Management of Oregon's Trout 1987 Abstract -- The Statewide Trout Management Plan is part of the Oregon Department of Fish and Wildlife's (ODFW) planning program to provide a comprehensive, systematic, long-term approach to the management of Oregon's fish resources. The Plan contains specific goals, objectives, strategies, and guidelines for the statewide management of trout, which are based on state laws, as well as general goals and policies adopted by the Oregon Fish and Wildlife Commission, (hereafter referred to as the Commission). In turn, the Plan provides direction for basin, subbasin, and mini plans developed for individual rivers and water bodies. The relationship of the Statewide Trout Management Plan to other ODFW plans is further discussed in Appendix A. This Statewide Management Plan will direct future trout management and will be reviewed in 6 years. The plan contains brief descriptions of Oregon's trout waters, species, anglers, and economic consequences. The importance of habitat and the use of angling regulations are also discussed. The plan covers all species of native and introduced resident trout and Pacific salmon that are managed in the resident trout program (Atlantic salmon, kokanee, coho salmon, and Chinook salmon) and the anadromous form (searun) of cutthroat trout. Appendix B contains a complete list of fish treated as trout in the plan. Close

• 8. [Article] Catch, Migration, Growth and Survival of Stocked Coastal Cutthroat Trout in Munsel Lake, Oregon

  The latest phase of a study of the migration, survival, growth, and catch of coastal cutthroat trout, conducted to compare cutthroat trout and rainbow trout. The document describes the geological and biological ...

  Citation × Citation Citation Abstract Copy Title: Catch, Migration, Growth and Survival of Stocked Coastal Cutthroat Trout in Munsel Lake, Oregon Author: Oregon State Game Commission, Skeesick, Delbert G. The latest phase of a study of the migration, survival, growth, and catch of coastal cutthroat trout, conducted to compare cutthroat trout and rainbow trout. The document describes the geological and biological characteristics of Munsel Creek weir, where the studies were conducted. It also includes graphs of the data and a summary of the results. Title: Catch, Migration, Growth and Survival of Stocked Coastal Cutthroat Trout in Munsel Lake, Oregon Author: Oregon State Game Commission, Skeesick, Delbert G. The latest phase of a study of the migration, survival, growth, and catch of coastal cutthroat trout, conducted to compare cutthroat trout and rainbow trout. The document describes the geological and biological characteristics of Munsel Creek weir, where the studies were conducted. It also includes graphs of the data and a summary of the results. Close

• 9. [Article] Lake Billy Chinook Creel Survey, Boat and Bank Anglers - 2009 Estimated Catch and Effort, Sampled Catch and Effort, and Estimated Catch Rates

  Abstract -- Lake Billy Chinook Creel Survey, Boat and Bank Anglers - March 1-October 31, 2009

  Citation × Citation Citation Abstract Copy Title: Lake Billy Chinook Creel Survey, Boat and Bank Anglers - 2009 Estimated Catch and Effort, Sampled Catch and Effort, and Estimated Catch Rates Abstract -- Lake Billy Chinook Creel Survey, Boat and Bank Anglers - March 1-October 31, 2009 Title: Lake Billy Chinook Creel Survey, Boat and Bank Anglers - 2009 Estimated Catch and Effort, Sampled Catch and Effort, and Estimated Catch Rates Abstract -- Lake Billy Chinook Creel Survey, Boat and Bank Anglers - March 1-October 31, 2009 Close

• 10. [Article] Lake Billy Chinook Creel Survey, Boat and Bank Anglers - 2010 Estimated Catch and Effort, Sampled Catch and Effort, and Estimated Catch Rates

  Abstract -- Lake Billy Chinook Creel Survey, Boat and Bank Anglers - March 1-October 31, 2010

  Citation × Citation Citation Abstract Copy Title: Lake Billy Chinook Creel Survey, Boat and Bank Anglers - 2010 Estimated Catch and Effort, Sampled Catch and Effort, and Estimated Catch Rates Abstract -- Lake Billy Chinook Creel Survey, Boat and Bank Anglers - March 1-October 31, 2010 Title: Lake Billy Chinook Creel Survey, Boat and Bank Anglers - 2010 Estimated Catch and Effort, Sampled Catch and Effort, and Estimated Catch Rates Abstract -- Lake Billy Chinook Creel Survey, Boat and Bank Anglers - March 1-October 31, 2010 Close