How are mountain whitefish populations doing in Idaho?

Fisheries biologists use the term “salmonids” to refer to members of the biological family that includes salmon and steelhead, trout, grayling, and whitefish. In Idaho, we have many different species of native and nonnative salmonids, but by far the group that gets the least attention from anglers is whitefish. You might be surprised to know Idaho actually has several native species of whitefish, but most anglers are likely to encounter the mountain whitefish. That’s because they are often caught incidentally when anglers are fishing rivers for trout. Although Idaho Fish and Game biologists regularly monitor trout to determine if populations are healthy, they rarely monitor mountain whitefish populations. Recently, that changed, with the Department conducting two different studies to look at how mountain whitefish are doing across Idaho. 

In the first study, biologists used snorkel-count data from the Salmon and Clearwater basins of central Idaho that have been collected for decades. These snorkel surveys are used to monitor wild salmon and steelhead natural production, but other game species are counted too. Biologists found that mountain whitefish populations in most rivers of the Salmon and Clearwater basins were stable or increasing going back to the mid-1980s, except in the South Fork of the Clearwater River, where declines were noticeable. The stable conditions for most populations were not surprising given that more than one-third of central Idaho is backcountry and is a stronghold for other native salmonids, including salmon and steelhead, bull trout, and cutthroat trout.