Introduction
Figure 1. A program participant holding a northern pikeminnow
Northern pikeminnow are estimated to be responsible for 8% (16.4 million) of the 200 million juvenile salmonids lost to fish predation annually in the basin (Beamesderfer et al. 1996). In 1991, in an effort to decrease the high levels of predation on salmonids by northern pikeminnow and help offset juvenile mortality caused by dams, the Bonneville Power Administration began funding a sport-reward fishery program (Northern Pikeminnow Sport-Reward Program, hereafter abbreviated as NPSRP) in conjunction with the Pacific States Marine Fisheries Commission (PSMFC), Oregon Department of Fish and Wildlife (ODFW), and the Washington Department of Fish and Wildlife (WDFW) for removal of pikeminnow in the Columbia river. The area of the NPSRP extends from the mouth of the Columbia River to Priest Rapids dam and upstream in the Snake River to Hells Canyon dam (Beamesderfer et al. 1996; fig. 1). The program area is shown below.
The program targets pikeminnow over 228 mm in size and has a goal for an annual exploitation rate of 10-20% of the pikeminnow population (Porter 2010). Anglers earn 4, 5, or 8 dollars per fish depending on the payment tier in which they qualify. Anglers can also earn additional money if a fish caught is one that has been tagged by the ODFW for the purpose of the NPSRP (Porter 2010). Since the introduction of the program 3.5 million pikeminnow have been removed. Removal rates have ranged from 104,000 to 267,000 fish per year, with an overall cost of $78.2 million (Porter 2010).