This project is proposed as on-site, partial mitigation for impacts of Albeni Falls Dam.  Fall draw downs of the naturally created Lake Pend Oreille greatly reduced the amount of shoreline spawning habitat for kokanee, the primary forage of bull trout and rainbow trout.  Studies of lake level management to improve kokanee spawning began in 1996.  Both the ISRP and the USFWS commented that the original 3-year study should be extended for 2 generations of kokanee.  Results to date show a two-fold increase in kokanee egg-to-fry survival when lake levels were raised after a full drawdown year.  We propose work in 2007 as the final year of this study.  In 2007, kokanee fry will be estimated by hydroacoustics.  Fry will also be netted to collect unbiased samples from each section of the lake.  They will have their otoliths removed and sent for analysis to determine the percentage of wild and hatchery fry. Egg-to-fry survival rate will be calculated based on the number of eggs estimated in 2006 and results compared to previous years.  After 2007, we propose lake-wide hydroacoustic surveys as a quick, cost-effective method to monitor the kokanee population.
This study also documented a new threat to the current ecosystem.  Exceptionally high predation levels could extirpate kokanee from the lake.  Without kokanee, lake trout and bull trout would be in direct competition for a limited food supply.  In Flathead Lake, Montana and Priest Lake, Idaho, lake trout replaced bull trout once the kokanee forage base was gone.  We therefore propose the objective of restoring the bull trout population so that it is healthy enough to provide a harvest of 1,000 fish annually in the lake.  To accomplish this objective we propose several tasks including the direct removal of lake trout using trap nets and gillnets, and examining the fall draw down of the lake to see if it can be used to reduce the survival of lake trout eggs.  Rainbow trout are the main kokanee predator.  Management actions will continue to attempt to reduce rainbow trout abundance until the kokanee population increases.  We propose to develop a method to monitor the population through up-looking hydroacoustics to see if these actions are effective.  We also propose to hold annual workshops to disseminate information encouraging anglers to harvest the predators they catch until the predator/prey balance can be restored in the lake.
We further propose to evaluate the stocking of hatchery kokanee into the lake.  To our knowledge the Cabinet Gorge Fish Hatchery, which annually stocks the lake, is the largest kokanee hatchery in the world and was built with funds from the US Army Corps of Engineers and Avista Power Company.  The hatchery stocks up to 18 million fry at a length of 50 mm, and yet the kokanee population has not recovered.  We propose to continue to mark the otoliths of all hatchery-produced kokanee, monitor their annual survival rates, and compare this to survival rates of wild kokanee.  Data collected to date indicates declining survival of both hatchery and wild kokanee fry as stocking increases; possibly due to the concept of “apparent competition”.  
Field work in this proposal is to be conducted by the Idaho Department of Fish and Game.  A subcontract is proposed with the Washington Department of Fisheries to examine kokanee otoliths to determine if they are of wild origin. A subcontract is also proposed for commercial fishermen to operate trap nets for lake trout removal.

               The Statement of Work has five objectives. Following each objective below is a statement of how the work elements will meet these objectives:

Objective 1-  Kokanee restoration, "To restore kokanee abundance in Lake Pend Oreille so that it is capable of sustaining a harvest of 750,000 kokanee on an annual basis, within the next 10 years."  Several work element address this objective.  Work element M, Produce Plan,  Assist USFWS with Long-term Lake Level Management Planning, will be to develop a long term winter draw down plan for Lake Pend Oreille.  Fluctuating the winter water level has been shown to increase spawning habitat for kokanee and increase their egg-to-fry survival by 2.5 times. Work element F and G, "Determine kokanee egg-to-fry survival in 2007"and "Analyze kokanee fry survival in 2007" will be to monitor Work Element M to see if it is working . Work Element B, "Monitor shoreline spawning habitat" is to see if the long term plan in Work Element M is producing the desired habitat.   Work Element C "Lake level manipulation to impact lake trout spawning, also addresses Objective 1.  The lake trout are at an all time high and their predation on kokanee threatens to collapse the stock.  This work element is to try to reduce their abundance by de-watering their eggs after spawning.  Work element E, "Lake trout removal by trap nets and gillnets" is an attempt to remove lake trout to reduce predation on kokanee so that kokanee can recover.  Work element H, "Monitor kokanee population" will determine if these efforts are successful.

Objective 2 - Bull trout / Cutthroat trout Preservation,  "To reduce the lake trout population to < 4,000 fish over 52 cm within one lake trout generation (10 years) to reduce the risks to other species".  Work elements E, "Lake trout removal by trap nets and gillnets" and Work Element C "Lake level manipulation to impact lake trout spawning",  both are to reduce the number of lake trout, which are known to be a competitor of bull trout and a predator on cutthroat trout.  

Objective 3-  Restore Bull Trout,  "To restore bull trout so that they can meet USFWS recovery criteria and provide a fishery with a harvest of 1,000 fish annually in Lake Pend Oreille by 2030".  This is similar to object 2 in that work element E and  work element C  above, also help meet this objective.  In addition, efforts to reduce rainbow trout will also help this objective since kokanee are the main food supply for bull trout and rainbow trout predation on kokanee is also too high.  Work element D, "Estimate rainbow trout using up-looking hydroacoustics" is to develop a method to determine rainbow trout abundance to see if the current reduction efforts are successful.  These current reduction efforts include a $15/fish bounty program on rainbow and lake trout this winter, and a $10 bounty on them during summer.  Work element J, "Evaluate predator reduction program", is to calculate the kokanee population's survival and yield to see if they are responding to recovery efforts.

Objective 4-  Improve stocking program for kokanee,  "Improve the stocking program for kokanee in Lake Pend Oreille so that it contributes 375,000 kokanee to the harvest annually, without having hatchery kokanee replace the wild stock within the lake". Work element K is to examine present and past data to see if the hatchery stocking of kokanee is impacting wild production and reducing survival of hatchery fry.

Objective 5,  Information Dissemination, " To have other fishery managers and biologists that face similar problems be able to learn from the results of our study". Work elements L "Produce manuscript" and Work Element O " Annual Progress Report" are to allow other biologist to learn from the results of our study by reading reports.