Idaho’s state fish, Westslope Cutthroat Trout, are a staple in many of the state’s major rivers and lakes. Cutthroat were once widely abundant in North Idaho’s large lake systems, where they spawned in tributary streams and grew large in the lakes where food was more abundant. Although cutthroat once dominated the angler catch in the Panhandle’s large lakes, they are no longer the primary target species.
Harvest of cutthroat in waters such as Priest Lake was upwards of 4,000 fish per year in the 1950s, but declined to hundreds of fish by the 1980s. Declining catch rates were the result of declining fishing effort and population size, changing fish communities, and impaired tributary spawning habitats. Fishery managers concerned about cutthroat responded by restricting harvest opportunities to rebuild populations. Today, cutthroat represent one of the most abundant species in many streams around Priest and Upper Priest lakes and are moderately abundant in both lakes. Though cutthroat anglers aren’t as numerous as they used to be, those that target them for catch-and-release say fishing is good.
In an effort to better understand cutthroat population trends in Priest and Upper Priest lakes, Fish and Game managers developed a monitoring strategy first implemented in 2014. They sampled cutthroat throughout Priest and Upper Priest lakes in late spring using gill nets set for short durations and designed to catch multiple sizes of fish. The gill nets weren’t intended to provide an estimate of the total number of cutthroat in the lake, but rather an index of their abundance. The index of abundance, in this case measured as the number of fish per net, can then be used to compare the population from year-to-year and from lake-to-lake.
In our 2017 sampling, cutthroat ranged in size from 6 to 21 inches. We caught an average of one cutthroat per net in Priest Lake and more than three cutthroat per net in Upper Priest Lake. Catch rates from this survey suggested cutthroat are moderately abundant in both lakes, but more cutthroat use Upper Priest Lake.
The difference in cutthroat abundance between lakes is related in part to a difference in the abundance of large predators. Lake Trout, a large predatory fish, are far more abundant in Priest Lake than Upper Priest Lake. Currently, Priest Lake is managed with the intent of providing lots of Lake Trout to catch and harvest. In contrast, Upper Priest Lake is managed to conserve native fish species like cutthroat trout. This involves removing lake trout from Upper Priest Lake each year to reduce their impact on cutthroat. The current Idaho Fisheries Management Plan identifies each lake will be managed differently, but not all anglers agree that it’s the right approach.
Fisheries managers have worked with local stakeholders to set future management direction for Priest and Upper Priest lakes. Three alternatives were recently identified for broader public input. One option is to maintain the existing management strategy, which favors lake trout in the main lake. Another is focused on enhancing kokanee, cutthroat trout, and bull trout, which requires managing against lake trout in the main lake. Yet another and even more challenging alternative would attempt to strike a balance that allows all species to be present at fishable levels.
Stakeholders expressed strong support for conserving native species in Upper Priest Lake, thus each of the management alternatives include continued lake trout suppression in the upper lake.
Public input is being requested to help determine which alternative has the greatest public support. Please consider taking the online survey if you would like to share your opinion.