Yellowstone National Park is managed to protect cultural and natural resources and outstanding scenery, and to provide for visitor use. Angling has been a major visitor activity for over a century. Present regulations reflect the park's primary purposes of resource protection and visitor use. The objectives of the fishing program are to:

In Yellowstone, bald eagles, ospreys, pelicans, otters, grizzly bears, and other wildlife take precedence over humans in utilizing fish as food. None of the fish in Yellowstone are stocked, and populations depend on sufficient number of spawning adults to maintian natural reproduction and genetic diversity. In Yellowstone National Park, we place less emphasis upon providing fishing for human consumption and put more emphasis upon the quality for recreational fishing. Anglers, in return, have the opportunity to fish for wild trout in a natural setting.

Yellowstone Moves to Protect
Native Fish Species

As of the summer of 2001, all native sport fish species in Yellowstone National Park became subject to catch-and-release-only fishing rules. The native species affected by this change are the cutthroat trout and its several subspecies, Montana grayling, and mountain whitefish. Most of the park’s native fishes have been included under catch-and-release-only fishing rules since the early 1970’s. The changes effective in 2001 primarily affect populations in Yellowstone Lake, its tributaries, and the upper Lamar River.

Due to evidence that invasive introduced organisms such as lake trout, whirling disease, and New Zealand mud snails are having negative effects on Yellowstone’s native sport fish, the 2001 changes seem to be the next logical step to help repair the tremendous damage being done to the native species.

Yellowstone cutthroat trout have declined throughout the west and are currently designated as a "Species of Special Concern-Class A" by the American Fisheries Society. A formal petition to list this subspecies as "threatened" throughout its range was submitted to the U.S. Fish and Wildlife Service in 1998. Yellowstone National Park represents approximately 91% of the current range of Yellowstone cutthroat trout and contains 85% of the historical lake habitat for this subspecies, so the park is considered crucial to the survival of the species.

Yellowstone cutthroat trout generally declined in the second half of the 20^th century due to angler overharvest, competition with exotic fishes, and overzealous egg collection. Populations rebounded in the park after the advent of catch-and-release-only fishing rules in the 1970’s, but new and aggressive invaders are causing an increasing threat to these native fish and alarming park fisheries biologists. Nonnative lake trout, an effective fish predator, were discovered in Yellowstone Lake in 1994. Throughout the west cutthroat trout populations preyed upon by introduced lake trout have typically declined, exhibited lower growth, or have disappeared. Aggressive lake trout control efforts by the National Park Service and no harvest limits have resulted in removing thousands of lake trout from Yellowstone Lake since 1994, including more than 12,000 in 2000. Still, the number of Yellowstone cutthroat trout monitored during the annual fall count in Yellowstone Lake was lower in recent years than at any other time in the 25-year history of the monitoring effort. Whirling disease, which has been implicated in recent years in the decline of trout populations in many western states, was discovered in Yellowstone Lake in 1998. So far, it is unclear which of these two nonnative invaders has been the greater factor in the decline of Yellowstone cutthroat trout, but there is no question they are causing it.

Other native sport fish, including westslope cutthroat trout and Montana grayling, have been under catch-and-release-only fishing rules since 1973. This is the first time mountain whitefish have been placed under such rules in Yellowstone National Park. The new rule gives mountain whitefish equal status to the other native sport fish in the park.

In addition to the catch-and-release-only fishing rules, the opening date of the fishing season on Yellowstone Lake returned to its historical date of June 15 for the 2001 fishing season. From 1998 through 2000, Yellowstone Lake’s opening date was moved forward to June 1 in an attempt to give anglers a greater chance of catching nonnative lake trout, but monitoring showed that during the early June period, anglers caught several thousand cutthroat trout for every lake trout caught. Because of incidental hooking mortality of released fish, this negates the positive impact of the angler catch of lake trout.