Yellowstone Cutthroat to be Counted

By Harry Morse, Southeast Region Last year 4,747 native Yellowstone cutthroat trout were counted at the fish trap on the Upper Blackfoot River east of Soda Springs. Fish and Game biologists installed the mobile trap again this year and are ready to start counting fish. "We install this trap to get an accurate count on how many adult Yellowstone cutthroat trout return up river to spawn and to find out how many introduced rainbow trout are trying to return up river to spawn," biologist Dave Teucher said. "This year we will also be taking genetic samples. The genetics work provides a method for determining if rainbow and cutthroat trout have been interbreeding." A late cold winter delayed the installation of the trap. The migration usually begins with the first flush of water in the spring, which stimulates mature cutthroats to swim up river to the trap area. Recent warming weather should increase water flows and trigger migration. The trap is manned 24 hours a day by a seasonal Fish and Game biologist. He counts the fish, keeps the trap clear of debris, and provides security. The number of returning native cutthroat trout has increased dramatically over the past 10 years. In 1992 fewer than 1,000 cutthroats returned while 4,747 returned in 2001. The Upper Blackfoot River has been intensively managed for more than a decade to return abundant numbers of native cutthroats to the river. Currently, only catch-and-release fishing is allowed on the Upper Blackfoot and that is delayed until July 1, after spawning season has taken place. Rules do not allow native cutthroat trout to be kept in Blackfoot Reservoir where they spend most of their life cycle. The management plan that curtailed harvest appears to be working, according to Teuscher. Twenty five percent of all fish caught on the reservoir last year were native cutthroat while in 1997 adult cutthroat trout made up only five percent of the catch. The adult run has substantially increased. The trap will be operated until the migration ends in early June.