Book Excerpt : Fish and Fishing

You may wonder, why is it okay to catch and eat fish in Yellowstone Park when we are forbidden to kill or capture all other animals, pick wildflowers, or even take away non-living rocks? People began to question park policy toward fishing a few decades ago, and fishing practices began to change. The park now charges a fee for fishing licenses, which had always been free. As of the 2001 fishing season, all native sport fishing is catch and release only.

The number of anglers has dropped, but these anglers probably land more fish. Some people enjoy watching the fish feed, fight, and spawn at Fishing Bridge or swim upstream at LeHardys Rapids to reach their spawning grounds. More important to the ecosystem, the bears and fish-eating birds, who were beginning to be deprived of a major element of their diet, now profit by the upsurge in the number of fish available.

There are about 20 species of fish in the Greater Yellowstone Ecosystem. The types of sport fish most common to Yellowstone's waters are native cutthroat trout (Oncorhynchus clarki) and four introduced species: rainbow trout (Oncorhynchus mykiss), brown trout (Salmo trutta, brought in 1890 from Scotland and Germany), brook trout (Salvelinus fontinalis), and lake trout (Salvelinus namaycush). Two less common native fish are mountain whitefish (Prosopium williamsoni) and Montana grayling (Thymallus arcticus montanus).

Fisheries in Trouble

Yellowstone's fisheries currently face four problems: predation by lake trout, tapeworms, whirling disease, and the New Zealand mud snail invasion.

Lake Trout

Hanging until recently at the Fishing Bridge museum was one of the largest fish ever caught in the park, a 37-pound (17-kg) lake trout pulled from Heart Lake in 1935. Although some larger lakes of southern Yellowstone were stocked with lake trout, these large predator trout were never known to live in Yellowstone Lake until a few years ago. In Yellowstone Lake, they have the capability to wipe out the lake's population of cutthroat trout, a consequence that would have a huge impact on grizzly bears, eagles, and pelicans.

The problem is being studied. Crews had gillnetted nearly 198,000 lake trout by the end of 2006, and other remedies are being sought, but it's unlikely that all lake trout can ever be removed from the lake. Meanwhile, anglers must keep all lake trout they catch and bring them to a ranger for verification.

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 This is an excerpt from Yellowstone Treasures, 2nd edition, pages 349–50.

To read the rest about the disease problems facing Yellowstone's fish, as well as the invasion of the mud snail, get the book!

Revised January 7, 2008. Copyright 2005. All Rights Reserved.