1 / 15

Collaborative Restoration of Bonneville Cutthroat Trout in Lower Logan River

This study, led by experts from USU, UDWR, and other organizations, aims to restore Bonneville cutthroat trout (BCT) to high-quality habitats in the lower Logan River. Key objectives include evaluating management strategies for the exotic brown trout population, testing removal techniques, and examining biotic resistance to better understand the dynamics between native and invasive species. By isolating tributaries for BCT recovery and monitoring trout demographics, the project seeks effective methods to protect and promote the native fish population.

ulric
Télécharger la présentation

Collaborative Restoration of Bonneville Cutthroat Trout in Lower Logan River

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Can a Collaborative Restoration Really Accomplish Anything? W. Carl Saunders and Phaedra Budy (USU) Paul Burnett (UDWR) Paul Holden (Cache Anglers, TU) Paul Chase (USFS)

  2. Goals & Objectives • Restore BCT to tributary • Restore Bonneville cutthroat trout to high quality habitat in lower Logan River

  3. Goals & Objectives • Evaluate alternatives for managing exotic brown trout • Test effects of two brown trout removal intensities on demographics of BCT populations • Test for evidence of Biotic Resistance and identify cutthroat trout density thresholds sufficient to resist brown trout invasion • Restore BCT to tributary • Restore Bonneville cutthroat trout to high quality habitat in lower Logan River

  4. Area of Detail Salt Lake City UTAH N 0 2 4 6 8 1 0 Km Reference Treatment Study

  5. Flow • ~ 100% brown trout,5.6 km • Mechanical (60-80%) removal • Eventual chemical removal • Isolate tributary for BCT recovery • Cache Anglers (TU) -Plant BCT Right Hand Fork: restoration and treatment study area - removal Logan River, mainstem SOURCE Brown Right Hand Fork, tributary City of Logan

  6. Logan River, Between the dams: treatment study area – reduction. 6 km to Right Hand Fork Flow • 85% brown trout, 2.0km • Mechanical removal (reduction); 60-80% • Allow natural brown trout and cutthroat trout re-colonization SOURCE Third Dam Logan River, mainstem SOURCE Second Dam City of Logan

  7. Summary of Removal efforts • Increase in effort in Logan River, 2010 (~35% ) • After 1-year of removal, increase in density from 2009 to 2010 (12, 108% increase)

  8. RHF – Length Distribution brown trout • 2010 Strong recruitment pulse • Suggests strong density dependent effects

  9. RHF – Length Distribution brown trout SOURCE • 2010 Strong recruitment pulse • Suggests strong density dependent effects

  10. RHF – Length Distribution cutthroat trout • Observed first cutthroat trout recruitment in 2010

  11. Logan River – Length Distribution brown trout • Shift in population size structure less apparent than RHF • Immigration from dams likely

  12. Logan River – Length Distribution brown trout RECOLONIZATION • Shift in population size structure less apparent than RHF • Immigration from dams likely

  13. Conclusions • Brown trout response • Dramatic recruitment response: density dependence in RHF • Source for lower river, emigration of YOY • Rapid re-colonization by mature brown trout into Logan River • Removal efforts provide opportunity to test for evidence of Biotic Resistance and evaluate management options • Can we identify threshold densities or configurations (size/age) above which brown trout cannot replace native trout? • Possible to simply reduce (but not eliminate) the abundance of exotics, to protect native populations of fish?

  14. RHF – Cumulative Length Distribution brown trout • Recruitment pulse greater than observed before removal efforts

  15. Logan – Length Distribution

More Related