Pend Oreille Rainbow Harvest Encouraged

By Phil Cooper, Panhandle Region Conservation Educator For the past two years, the Idaho Department of Fish and Game has been encouraging Lake Pend Oreille anglers to harvest rainbow trout. While it is almost unprecedented for a state conservation agency to be encouraging harvest of rainbows, a predator/prey imbalance threatens the species composition and the future of fishing in the huge lake, where the largest freshwater rainbow in the world was caught in 1947. Lake level management practices which make much of the spawning substrate unavailable, and the floods of 1996 and 1997, have together had negative impacts on the population of kokanee salmon in the lake. Fish and Game fisheries manager Ned Horner has been warning of a potential collapse of the kokanee population and a subsequent loss of the trophy fishery for Kamloops rainbow trout. The rainbow depend upon kokanee as their primary food source. In February of 2000, the kokanee fishery was closed for the first time in history, and rainbow and lake trout limits were liberalized to encourage harvest of predators of kokanee. Predation of kokanee by lake trout and rainbows poses the greatest threat to the continued existence of kokanee in Pend Oreille. Quickly reducing the number of predators is the best hope for preventing a kokanee collapse. Should kokanee populations collapse, there are too many predators in the lake to ever bring the balance back. Anglers are now asking if the program is working. There is no simple answer to that question. Kokanee population estimates conducted this fall by Fish and Game research biologists are yet being analyzed. Kokanee otoliths (ear bones) are being examined to determine how many of the fish are naturally produced and how many are from the hatchery. It will be another month or more before we have specific information on the status of the kokanee, but two things were apparent from the preliminary data. The good news is that kokanee fry production was excellent in both 2000 and 2001, and these two strong year classes offer the opportunity to rebuild the kokanee population. The bad news is that survival is still poor for older kokanee, indicating predation remains a problem. All the gains in kokanee fry the past two years could easily be eaten up if predators are not reduced. Creel census results show anglers are only keeping 40 percent of the rainbows they catch. They are keeping 78 percent of the lake trout they catch. Some anglers have expressed a reluctance to harvest rainbows because they do not want the fish to go to waste. Fish and Game Fisheries Manager Ned Horner has developed a Fish for Families program in cooperation with the Bonner County Food Bank and area marinas. The food bank is currently assisting more than 1,000 people in Bonner County and they can always use fresh fish to meet the needs of local families. Anglers who catch fish they would like to donate to the food bank may take them to Ellisport Bay (Holiday Shores and Hope Marine), Garfield Bay (Harbor Marina), and Bayview (MacDonald's Hudson Bay Resort). They will gladly accept whole fish, cleaned or uncleaned (please help out by gutting them) when the angler fills out a proxy form to assure compliance with state laws on possession of fish. The food bank will keep track of total numbers of fish, but not individual angler harvest. November is the best month for rainbow fishing on Pend Oreille Lake. If you are successful at catching a rainbow or a lake trout, take it home for dinner. If you catch more than you can use, help the needy by contributing to the Bonner County Food Bank through the Fish for Families program. Your contribution will help a needy family and help to restore the species balance in Lake Pend Oreille.