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LAKE PEND OREILLE Fishery in Crisis

LAKE PEND OREILLE Fishery in Crisis. NATIVE SPECIES. Westslope cutthroat trout Bull trout Mountain Whitefish Pygmy Whitefish Native cyprinids (RRS, LND, PM, NPM), Largescale & Longnose suckers. INTRODUCED SPECIES. Lake Whitefish – 1889 Bass - 1900 Lake Trout - 1925 Kokanee - 1933

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LAKE PEND OREILLE Fishery in Crisis

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  1. LAKE PEND OREILLEFishery in Crisis

  2. NATIVE SPECIES • Westslope cutthroat trout • Bull trout • Mountain Whitefish • Pygmy Whitefish • Native cyprinids (RRS, LND, PM, NPM), Largescale & Longnose suckers

  3. INTRODUCED SPECIES • Lake Whitefish – 1889 • Bass - 1900 • Lake Trout - 1925 • Kokanee - 1933 • Rainbow Trout - 1941 • Mysis Shrimp – 1968

  4. Historic Factors in Kokanee Decline - Dams Albeni Falls Dam -Located 26 mi. downstream on Pend Oreille River. -Annual fluctuation of 11.5 ft -Drawdown after kokanee spawned was fixed in 1966. Cabinet Gorge Dam -Located 10 mi. upstream on Clark Fork River. -Blocked access to hundreds of miles of tributaries (Ct & Bt). -Loss of 100,000 kokanee, but spawning run 4-5 million then.

  5. Other Factors Kokanee Decline Mysis Shrimp • Introduced in 1968, established by 1974. • Independent research - no competition currently, but kok harvest reduced to 350,000. Deeper winter drawdowns • 1966 COE decision to maximize hydropower • Reduced kokanee shoreline spawning habitat. • USFWS BT “BiOp” has driven “drawup”

  6. 2008- 30% 2009- 70%

  7. Predation Studies Predator:Prey Ratio 1:4.2 in LPO Not enough prey to support predators

  8. LPO Fishery Collapse Not a New Issue • Depressed kokanee reduced further by 1997 flood. Loss of kokanee means problems for trophy trout and char. • Emergency rule changes in 2000, but no improvement by 2002. Socially not accepted. • March 2002 workshop showed support for Citizens Advisory Committee.

  9. Commercial Lake Trout Fishery • Establish commercial rod-and-reel fishery for lake trout. IFG Commission approved Dec. 2002. • LT approved as commercial species, no limit on rods, limited to 10 licenses. • Support evaluation of deep water trap nets (live entrapment gear).

  10. Why are Lake Trout a Threat? • Have replaced bull trout populations across BT range. • Collapsed popular kokanee sport fisheries in Priest and Flathead lakes. • Threaten Yellowstone CT and YNP ecosystem.

  11. Deepwater Trap Nets 101: • Live entrapment, selective for LT/LWF • BIG gear • Set at depths of 60-180 ft. • Lifted 2-3 times a week

  12. Total Catch (9 nets)* *19,075 hrs 2005 *31,025 hrs 2003

  13. Lake Trout Population Estimate 10,095 9,870 8,448 6,376

  14. Commercial LT Fishery • Implement March 2003 – 10 licenses allowed • Total fish harvested by fishery: • 2003 – 305 (7 licenses) • 2004 – 497 (3 licenses) • 2005 – 425 (3 licenses) • Total for 40 months – 1,227 fish ~5% Exploitation rate; need > 50% to impact population

  15. Since 2006 anglers have turned in nearly 50,000 lake trout and 25,000 rainbow trout. Did LT Angler Incentive Awards Work?

  16. Fishery in Crisis • KOK fishery has collapsed, population continues to decline towards extinction – 3 years (same pattern as Priest Lake and Flathead Lake) • Trophy RBT will collapse on heels KOK • LT population continues to increase; LT eating 35% of KOK • RBT still consuming highest percentage (62%) of KOK We need to increase harvest of predators to save the fishery – Action is needed NOW!

  17. Attacking The Problem • Formed LPO “Task Force” • Increase predator harvest – RB and LT (>50% exploitation rate sustained) • Angler incentive programs - $10/fish in 2006, $15/fish since 2007 • Continued experimentation with commercial fishery ideas

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