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Learn about the successful management of northern pikeminnow in the John Day Reservoir and system-wide, including impact on fisheries, evaluation, and future strategies. The project outlines efforts by BPA, WDFW, ODFW, and PSMFC, achievements in reducing predation, over 2.7 million fish removed, and future plans for 2006 and beyond.
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Northern Pikeminnow Management Program Project 199907700
Cooperators Outline • Background • Fisheries / Harvest • Evaluation • What’s New • Accomplishments BPA WDFW ODFW PSMFC
Background JOHN DAY RESERVOIR (1983-86) Losses to predation Diet, salmonids Population
John Day Reservoir (continued) Northern pikeminnow predation increased with size
Background SYSTEM-WIDE (1990-92) Predation Relative to John Day Reservoir Below Bonneville Dam = 800% Lower Columbia Reservoirs = 325% Lower Snake River Reservoirs = 40% Loss to Predation = 8% of Population
Background 10-20% Exploitation = 50% Reduction in Predation Assumes no compensation by remaining predators: abundance, growth, fecundity, age structure, et al. Fisheries implemented systemwide in 1991
Priest Rapids Dam Hell’s Canyon Dam Program Area
Northern Pikeminnow Fisheries Sport Reward (WDFW) 1991-Present Dam Angling (ODFW, CRITFC, et al.) 1991-2002 Gill Net (CRITFC, YIN, et al.) 1994-2002
Sport Reward Effort, 1991-2005 Angler Days (in thousands)
Northern Pikeminnow Exploitation, Sport Reward (> 250 mm FL), 1991-2005
Compensation? Abundance, density, age, growth, fecundity, consumption, condition No Northern Pikeminnow Smallmouth Bass Maybe Walleye No
Northern Pikeminnow Electrofishing Catch Rates, John Day Reservoir
Diet Composition (samples with identifiable fish), Columbia and Snake Rivers, 1999, 2004-2005
Recent Changes and Plans for 2006 • Institutionalize Reward Structure • Rolling Biological Indexing • Re-institute Dam Angling • Update Predation Model • Multi-year Exploitation Rates • Addition of Two Sport-reward Stations
NPMP Accomplishments, 1991-2005 • Over 2.7 million Northern Pikeminnow Removed • Low Impact to Resident / Anadromous Species • >10% Exploitation Achieved in 13 of 15 Years • Estimated 22% Reduction in Salmonid Predation • Compensation by Remaining Predators Minimal • Credible Science: ~30 Journal Articles Published • Cost Effective