четверг, Декабрь 05, 1996WHO? Montana Fish, Wildlife & Parks--in cooperation with the U.S. Forest Service, the federal Bureau of Land Management, the U.S. Fish and Wildlife Service, Montana Power Company, Montana State University, private landowners, and conservation groups--is considering a proposal to recover Montana's state fish, the westslope cutthroat trout, in the whirling-disease plagued upper Madison River drainage. WHAT? The Madison River Westslope Cutthroat Trout Recovery Project would seek to restore westslope cutthroat trout in the headwater portions of the upper Madison River tributaries with hopes of developing a fishable population of westslope cutthroat trout in the Madison River. The long-term goals of the effort are to: (1) protect or establish genetically pure populations of westslope cutthroat trout in headwater areas of tributaries of the upper Madison River by 2006; and (2) develop a fishable westslope cutthroat trout population in the Madison River that would partially replace rainbow trout lost to whirling disease. Officials emphisized that this project would be conducted in concert with FWP's on-going efforts to determine if there are some possible clues for rainbow survival in other Madison River locales in both the upper and lower drainage. WHEN & WHERE The initial westslope cutthroat trout recovery effort would begin in the spring of 1997. Streams identified as candidates for restoration in 1997 include: Soap and Gazelle creeks, both tributaries to the West Fork of the Madison River; and on Standard Creek and an unnamed spring creek, both upper Madison River tributaries. At this time, researchers believe whirling disease is not likely to be in these streams and that the streams are relatively free of tubifex worms. The streams will be extensively examined before recovery work begins. Twenty-six additional upper Madison River tributaries have been identified as potential candidates for westslope cutthroat trout recovery. FWP hopes to reestablish westslope cutts to least 10 of the candidate streams by 2001. HOW? The project would seek to study, protect, and enhance westslope cutthroat trout in the headwater portions of upper Madison River tributaries in a number of ways including: habitat restoration, barrier construction, removal of non-native trout, and reintroduction of westslope cutts. Under the proposal, tributaries selected for westslope cutthroat trout restoration must show a low incidence or be free of whirling disease. They similarly must show low or no tubifex worm populations. The thread-like tubifex worm must be present in the system in order for the complicated whirling-disease parasite to complete its lifecycle. Before restoration work commences, each stream will undergo extensive examinations and surveys to determine if they are truly capable of supporting wild populations of westslope cutthroat trout. Most projects will be evaluated in an environmental assessment. WHY? For two primary reasons:
(1) The westslope cutthroat trout is Montana's state fish and an important part of Montana history, culture, and outdoor heritage. They evolved as aggressive feeders, a necessary adaptation for a species native to the cold, pristine, and relatively unproductive waters of Montana. Today, the range of westslope cutthroat trout is greatly reduced. This "species of special concern" is found in less than 5 percent of its historic range in the Missouri River drainage, and less than 10 percent of is historic range statewide. FWP is taking positive steps to preserve and expand the habitat and the populations of our state fish to keep the management of westslope cutts in Montana's hands, and to ensure that the fish need not be listed under the federal Endangered Species Act.
(2) Whirling disease has caused a 90 percent decline in the Madison River's rainbow trout population. Researchers like FWP Whirling Disease Coordinator Dick Vincent believe that because cutthroat trout begin their lifesycle in tributary streams they may simply avoid being infected at an early age when trout are most vulnerable to whirling disease. While biologists are not expecting to see a one-for-one replacement of rainbow trout with cutthroat trout, they do expect a partial replacement, with cutts filling part of the niche left by the rainbow-trout decline. Biologists are already picking up increased numbers of catchable cutthroat trout in the upper Madison River, fish likely recruited from headwater tributaries. Electofishing data collected from the 3-mile-long Pine Butte section, which is open to catch-and-release fishing, show an incidental count of about 40 catchable cutthroat trout in 1996 where fewer than six were counted prior to 1991.