1 / 12

Timing & Distribution of Coho Salmon in Lower Columbia River: Insights & Recommendations

Learn about the decline, management implications, and conclusions on naturally produced coho salmon in the lower Columbia River based on preliminary results. Understand the impacts of hatchery effects, genetic diversity, and federal listings.

kellyhbrown
Download Presentation

Timing & Distribution of Coho Salmon in Lower Columbia River: Insights & Recommendations

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. Timing and distribution of naturally produced coho salmon in the lower Columbia River

  2. Presentation overview • Background • Preliminary results • Management implications • Conclusions & recommendations

  3. Background • Declines in lower Columbia River coho salmon • Hatchery supplementation reestablished abundance • Reduced genetic diversity and hatchery effects on population • Federally listed in 2005 as “threatened” • Critical uncertainties research needed (avoidance vs mark selective)

  4. Conceptual condition Time

  5. Estuary Receiver Mainstem Gate Tributary Gate

  6. 129 coho instrumented in 2011, 303 in 2012 • In 2011 16 heard in tributaries of interest, 15 over Bonneville • In 2012 39 heard in tributaries of interest, 44 detected over Bonneville • Excluding Willamette avg/trib ~ 2 fish • Only Washougal didn’t have coho detected at gates, but more had fish only hit at one or vacate

  7. Results

  8. Results

  9. Results

  10. Results

  11. Conclusions • Multi-modal run-timing is not apparent in 2012 for CR coho salmon • Upper river fish appear to enter river earlier than lower river counterparts • Distance and speed positively correlated • Need to increase acoustic presence in estuary tributaries to greater account for fish • Need to increase transmitters out to get better presence in non-Willamette lower river tributaries

  12. Desired Status

More Related