Fish Passage Barrier to be Constructed at Akokala Lake

The environmental analysis and review for a proposal within to construct a fish passage barrier downstream of Akokala Lake in Glacier National Park’s North Fork District has been completed, and a decision was signed by the National Park Service Intermountain Regional Director to move forward with the project. The project is located in an area of recommended wilderness.

The fish passage barrier is necessary to protect native fish populations, including the threatened bull trout and genetically pure westslope cutthroat trout, from the potentially significant detrimental effects of non-native invasive fish species, including lake trout, rainbow and possibly brook trout. The structure will prevent non-native fish from accessing the uppermost Akokala Creek drainage, reduce the expansion of westslope cutthroat-rainbow trout hybridization, and protect Akokala Lake’s genetically distinct bull trout population. The structure will not impede downstream movements of native fish. Barrier construction will occur during late summer and fall, when water flows are low.

The beneficial effects to native fish will outweigh the negative impacts to wilderness character. Akokala Lake is one of the last bull trout supporting lakes on the west side of the park that is at risk of invasion but has not yet been colonized by non-native lake trout. Such status is extremely rare, not only in Glacier National Park, but throughout the Flathead River drainage. Protecting Akokala Lake against non-native invasive fish species will also help maintain the lake as an important high elevation habitat for native fish. The project is in accordance with other state and federal projects designed to conserve native fish species in the Crown of the Continent ecosystem.

An analysis of environmental impacts associated with the project and review of public comments were considered before making a final decision. The environmental assessment was released for public review in June of 2014. Twelve comment letters were received; nine letters expressed support, and one expressed opposition due to concerns about impacts to Glacier National Park’s recommended wilderness.

The environmental analysis and finding of no significant impact (decision document) can be found here.



Jeff
Hiking in Glacier National Park