In the early years of the park, fish from Yellowstone Lake were a specialty at the various hotels, and because there was no limit on the take, up to 7,500 pounds of fish were caught each year.

After commercial fishing was halted, park policy shifted to planting nonnative species. But by the 1970s,Yellowstone Lake had been devastated by overfishing, and new regulations were needed. Beginning in 1973, bait fishing was banned, Fishing Bridge was closed to anglers, and catch-and-release rules were put into place. Increased fish populations have been a boon for wildlife, especially grizzlies, bald eagles, and osprey.

Because of these regulations, Yellowstone National Park has achieved an almost mythical status when it comes to fishing. Each year 75,000 visitors spend time fishing in the park. The most commonly caught fish in Yellowstone are cutthroat, rainbow, brown, lake, and brook trout, along with mountain whitefish. Montana grayling are found at only a few small lakes within the park, most notably Grebe Lake.

The Yellowstone River is still considered one of the best places in the world to catch cutthroat trout, and the Madison River is a justifiably famous fly-fishing river with a wide range of conditions. Yellowstone Lake is where the lure anglers go to catch cutthroats and lake trout.

Beginners may have luck in the Gallatin River, but they’re less likely to do well in the Firehole River, where the fish are smart and wary. Peaceful Slough Creek in the northeast corner of Yellowstone is filled with fat rainbows and cutthroats, attracting fly-fishers from around the globe.

Several good books—available in local stores and visitor centers—provide tips on fishing Yellowstone waters. Try one of the following: Bud Lilly’s Guide to Fly Fishing the New West, by Bud Lilly and Paul Schullery (Frank Amato Publications), Yellowstone Fishes: Ecology, History, and Angling in the Park, by John Varley and Paul Schullery (www.stackpolebooks.com), or Fishing Yellowstone, by Richard Parks (www.falcon.com).

Trouble in Paradise

The last two decades were not at all kind to aquatic ecosystems in Yellowstone as a series of diseases and nonnative threats appeared. One of the greatest threats comes from lake trout (Mackinaw), a species that had been illegally planted—either accidentally or intentionally—in the 1980s or earlier. Lake trout were first discovered in Yellowstone Lake in 1994, and studies have since revealed that many thousands of them now inhabit the lake.

A highly aggressive and long-lived species, lake trout feed on and compete with the prized native cutthroat, threatening to devastate the population. (The average lake trout eats 80-90 cutthroat trout per year in Yellowstone.) Cutthroat spawn in the shallow waters of the lake’s tributary streams, where they are caught by grizzly bears, bald eagles, and other animals. Lake trout spawn in deeper waters that are inaccessible to predators, so fewer cutthroat and more lake trout could have an impact on grizzlies and eagles.

Eradication of the lake trout is virtually impossible, but the Park Service has used gill nets to catch many thousands of them. There are no size or possession limits on lake trout caught in Yellowstone Lake, its tributaries, and the Yellowstone River, but any lake trout you catch in these lakes must be killed and reported.

Another problem is threatening trout, especially rainbow trout, throughout the Rockies. Whirling disease, a devastating parasite-caused disease, has seriously hurt populations of rainbow trout in parts of the Madison River outside Yellowstone. The disease was discovered in Yellowstone Lake cutthroats in 1998, and there are fears that it could spread to other lakes and rivers in the park. It is spread in part when mud or water is brought in from contaminated areas on waders, boats, and boots. Be sure to clean up thoroughly with a bleach solution before entering or leaving an area. Get details on whirling disease at www.whirling-disease.org.

As if the other problems weren’t enough, New Zealand mud snails were discovered in park waters in 1995. These minuscule snails (natives of New Zealand) are now in the Firehole and Madison Rivers, where they can form dense colonies on aquatic plants and streambed rocks, crowding out native aquatic insects that are a food source for fish. It may be only a matter of time until other invasive exotic species—including zebra mussels and Eurasian water-milfoil—reach the Yellowstone ecosystem.

Help prevent the spread of these pests by carefully cleaning boots, clothing, waders, gear, and boats. Find out more about preventing the spread of these and other invasive species in the park’s Fishing Regulations brochure and online at www.cleaninspectdry.com and www.protectyourwaters.net.

Fishing Regulations

In most parts of Yellowstone, the fishing season extends from the Saturday of Memorial Day weekend in late May to the first Sunday of November, but Lake Yellowstone opens June 15, and the Yellowstone River above the falls opens July 15. Hayden Valley and some other areas are entirely closed to fishing, and only artificial lures and flies are allowed in the park. Lead cannot be used.

All native species in the park—fluvial arctic grayling, cutthroat trout, and mountain whitefish—are catch-and-release only. Barbless hooks are required because they cause less damage and are easier to remove. Three rivers—Madison River, Firehole River, and Gibbon River downstream from Gibbon Falls—are open only to fly-fishing. For complete details, request the park’s very detailed fishing regulations brochure, or find it online at www.nps.gov/yell/planyourvisit/publications.htm.

Fishing Fees

Anglers don’t need a state fishing license but must obtain a special Yellowstone National Park permit, available from visitor centers, ranger stations, Yellowstone General Stores, and fishing shops in surrounding towns. The adult fishing fee is $15 for a three-day permit, $20 for a seven-day permit, or $35 for a season permit. Kids under age 15 can get a free permit, or can fish without a permit under the supervision of an adult who has one. Park visitor centers and ranger stations have copies of current fishing regulations.