Timing and distribution of naturally produced coho salmon

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

Presentation overview Ø Ø Background Preliminary results Management implications Conclusions & recommendations

Background n n n 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)

Conceptual condition Time

Metric 2011 2012 Date of 1 st effort 8/28/2011 8/7/2012 Estuary Receiver Date of 1 st capture 8/28/2011 8/7/2012 Date of last effort 10/31/2011 10/30/2012 Date of last capture Mainstem 10/19/2011 Gate 10/30/2012 Days fished 69 132 Total coho captured 460 971 Coho captured/day Tributary Gate 6. 7 7. 4 Total instrumented 129 303 Total August instrumented 2 48 Instrumented/day 1. 87 2. 30

LCR Tributary n 129 coho 2011 instrumented in 2011, 2012 303 in 2012 River Elochoman 1 2 n In 2011 16 heard in tributaries of 1 Clatskanie River -15 over Bonneville Mill interest, Creek -0 Cowlitz River 39 heard in tributaries 7 n In 2012 of 9 Lewis River 44 detected over 1 5 interest, Bonneville Scappoose Creek -0 n Excluding Willamette avg/trib ~ 2 fish Clackamas River 0 1 n Only Washougal didn’t--have coho 0 Washougal River detected Sandy River at gates, but 1 more had 2 fish only hit at one or vacate Willamette River 2 19

Results 2011 Estuary Entrance 140 120 * * Catch (n) 100 80 Unmarked 60 Hatchery 40 * 20 0 33 34 35 36 37 38 39 40 41 Week Number 42 43 44 45

Results 2012 Estuary Entrance 140 120 * Catch (n) 100 * * Unmarked Hatchery * 80 * 60 * * 40 * 20 0 33 34 35 36 37 38 39 Week Number 40 41 42 43 44 45

Results Year Ultimate Fate LCR Tributary Bonneville Dam 2011 9/10/2011 9/8/2011 2012 9/15/2012 8/26/2012

Results 40. 0 35. 0 rkm/day 30. 0 25. 0 20. 0 15. 0 10. 0 5. 0 0 50 100 150 200 Distance to Swim (km) 250

Conclusions n n n 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

Desired Status