Although most anglers have heard of the major changes in fishing regulations on Lake Pend Oreille, many are still wondering exactly what the changes were, what those changes were based on, and what more is being done to help rebuild the kokanee population.
The Idaho Fish and Game Commission recently passed emergency rule changes for Lake Pend Oreille and the Clark Fork River to give anglers the opportunity to harvest more rainbow and lake trout (mackinaw), while restricting harvest of kokanee. Fishing for all species is now allowed year round in both Lake Pend Oreille and the entire Clark Fork River. The rainbow limit was increased to six fish, while there is no limit for lake trout (mackinaw). Kokanee were closed to harvest and bull trout remained closed to harvest. There were no changes in the cutthroat limit of two fish. What all this means is that an angler is allowed a general trout limit of six fish, of which no more than two can be cutthroat. If you had one cutthroat, you could harvest five more rainbow. Any lake trout you catch are in addition to your general limit of six other trout (rainbow, brown, cutthroat).
So why the switch from trophy rainbow management to a harvest-oriented trout fishery? Kokanee in Lake Pend Oreille are in serious trouble. We are currently looking at the lowest population levels ever recorded. We only had 280,000 age 3 fish, 80,000 age 2 fish and 250,000 age 1 fish in the fall 1999 population estimate. The average number of kokanee (during the last 22 years of trawling) in these same year classes is 730,000 age 3, 1.23 million age 2, and 1.45 million age 1 fish. Future spawners are going to be scarce and there is no way to "make" more of these older age class fish. We can only try to save what is left.
Survival rates of the kokanee most commonly eaten by predators (age 1 to 2 year old fish) have dropped from the typical 80+ percent to only nine percent. This is evidence that a predator bottleneck is present. Even with a big release of hatchery fry this year, if predators are not reduced, they will essentially consume all the available forage and leave nothing for the future.
Rainbow are being targeted because they are responsible for most of the kokanee predation (83 percent of the total). Rainbow are the most numerous predator in Lake Pend Oreille (15,545 rainbow, 12,928 bull trout, and 2,100 lake trout over 17 inches) and they rely almost exclusively on kokanee. Bull trout and lake trout eat a wider variety of food items. Rainbows grow faster than bull trout or lake trout, consuming more kokanee to fuel that growth. Although bull trout accounted for 14 percent of all kokanee consumed, harvesting bull trout currently is not an option due to their listing as a threatened species under the Endangered Species Act. Liberal regulations on lake trout since 1992 have already reduced their population and they were a minor part of kokanee consumption (three percent). To reduce predation of kokanee, the rainbow population needs to be reduced.
Why target rainbow spawners in the Clark Fork River? We knew that opening the Clark Fork River would be highly controversial, based on petitions urging the Department to close the fishery back in the early 1970s. At that time, the rainbow fishery was supplemented with an average annual stocking of 400,000 fingerlings from the Clark Fork Hatchery (no rainbow have been stocked since 1992). Rainbow were caught in the Clark Fork River from mid-October through mid-November and again in the spring in mid-May after they had spawned. The peak number of rainbow harvested in both the fall and spring fishery combined was 215 fish (harvest ranged from 34-215 in the fall fishery and 6-34 in the spring fishery, starting the fall of 1966 and ending the spring of 1972).
The daily limit back then was five fish over 20 inches. Catch rates averaged 27.1 hours/fish for the fall fishery (range 11.3 to 54.5 h/fish) and 115.3 hours/fish for the spring fishery (range 50.9 to 304 h/fish). So, even when tremendous hatchery stocking supported this fishery, anglers rarely if ever caught "a limit". The emergency rule change for 2000-2001 gives anglers the opportunity to harvest up to six rainbow a day, but it is unlikely that anglers will catch "a limit".
Harvest of rainbow in the Clark Fork River will not eliminate all rainbow spawners. A significant number of rainbow utilize tributaries of the Pack River as well as Granite Creek on the east side of the lake for spawning and these tributaries are not open to harvest.
The bottom line is that the regulation change will result in big rainbow being harvested from the Clark Fork River and that will mean fewer trophy fish available in the lake. We expect 100-200 fish to be caught out of the river, while 6,000-7,000 will likely come out of the lake. The Department decision to open the Clark Fork River was based on using known fishery options to meet the rainbow reduction goal.
What else is Fish and Game doing besides changing the regulations? On the kokanee side, we are requesting surplus eggs from other systems to bolster our own hatchery egg take. Systems that have provided eggs in the past have been Deadwood Reservoir in Idaho, Kootenay Lake in British Columbia and Lake Whatcom in Washington. The Deadwood and Lake Whatcom eggs have been provided free of charge in the past, but the Kootenay Lake eggs cost $5,000/million eggs to pay for the incubation costs required for disease testing (a federal U.S. requirement for importation). Egg availability always depends on adequate spawning runs to meet their own needs first, then have some surplus eggs to help Idaho. Nature plays a huge role at influencing run strength.
We are looking at converting the Clark Fork Hatchery raceways into a kokanee spawning channel similar to the Meadow Creek channel on Kootenay Lake. There are a lot of obstacles to conquer, funding being a major issue, but this channel could help to mitigate for the lack of shoreline spawning gravel caused by low winter lake levels.
Continuing to fight for changes in winter lake level management on Lake Pend Oreille is a critical part of kokanee recovery efforts. Kokanee are currently being limited by the lack of shoreline spawning habitat and higher winter pool levels the past two years have resulted in higher kokanee fry survival. The Lake Pend Oreille Idaho Club's lawsuit against the Corps of Engineers is an important attempt to get a seat at the decision table. Ultimately, Congress has the authority to modify the Corps' operating plan for Lake Pend Oreille. Federal hydropower projects do not go through relicensing like the Avista projects on the Clark Fork River did recently.
Finally, we have proven that the trophy rainbow fishery can be rebuilt relatively quickly with a combination of restocking and restrictive regulations. The Canadians have offered pure strain Gerrard rainbow from Kootenay Lake, B.C. when the time comes. Minimum size limits were very effective in building up a trophy rainbow fishery back in 1988. A strong catch-and-release philosophy by anglers made things happen more quickly than we predicted.
It is unprecedented to ask anglers to help knock down a trophy fishery we have spent a decade building up, but that is the reality of the situation. Anglers are the key to the future of Lake Pend Oreille right now, and with your help, we will get through this.