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Brook Trout Distribution and Monitoring
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[font "Comic Sans MS"][#cc9966]Surveys during the 1990s documented that brook trout currently inhabit almost 150 miles of water in 106 streams in east Tennessee outside Great Smoky Mountains National Park. This represents almost one-fourth of all wild trout water outside the Park. About two-thirds of the brook trout resource is located in Carter and Johnson counties and 70% occurs within the Cherokee National Forest. Genetic analyses have shown that about 55% of all Tennessee brook trout populations outside the Park are native, southern Appalachian fish. Another 15% are descended from stocked fish of northern (hatchery) ancestry and the rest are hybrids. The abundance and distribution of southern Appalachian brook trout are such that no special management of these populations is deemed necessary. All but two of the 73 brook trout populations identified in a brook trout inventory conducted during the late 1970s and early 1980s, were relocated in the 1990s.[/#cc9966][/font]
[#cc9966][font "Comic Sans MS"][size 1] [/size]Seventeen current brook trout populations represent successful restoration efforts involving the U.S. Forest Service, Tennessee Wildlife Resources Agency, and Trout Unlimited. A brook trout restoration project is currently underway in Short Creek, an Ocoee River tributary in Polk County (Region III). Until this effort, Polk County was the only east Tennessee county with wild trout populations that did not include any brook trout. Another restoration project in Little Jacobs Creek (Sullivan County) is set to begin this year. Most future projects will probably focus on a few larger streams that historically supported brook trout but typically do not contain them now.[/font][/#cc9966] [#cc9966][font "Comic Sans MS"]
[/font][/#cc9966] [font "Arial, Helvetica, adobe-helvetica, Arial Narrow"] [/font][#cc9966][font "Comic Sans MS"]Brook trout populations that have been protected by removing and excluding other trout species (i.e., managed) represent a substantial portion of Tennessee's current resource (36% overall and 64% south of the Park). However, most Tennessee brook trout populations still overlap with either rainbow or brown trout. It was encroachment by non-native rainbow trout and their apparent competitive superiority that caused the greatest concern with respect to the future survival of brook trout. But a recent study of Tennessee brook trout in 25 mixed populations (with rainbow trout) sustained no net loss in the amount of stream length they occupied between the 1970s and 1990s. Additionally, brook trout have recently "invaded" the abundant rainbow trout population in upper Sycamore Creek, established themselves, and continue to expand. The same thing happened in Briar Creek (Washington County) after brook trout were reintroduced without removing the rainbows nearly 17 years ago. [/font][/#cc9966] [#cc9966][font "Comic Sans MS"]
[/font][/#cc9966] [#cc9966][font "Comic Sans MS"][size 1] [/size]A study of brook and rainbow trout at annual monitoring stations on four streams has been underway since 1995 and a station on another stream has been studied since 1991. The objective is to document changes in the relative abundance of each species over time and how (or if) rainbows are eventually able to replace brook trout. A thorough assessment will likely require several more years of information. However, preliminary results indicate that despite fluctuations caused by event such as late winter/early spring floods (which are typically more harmful to brook trout reproductive success), brook trout are generally maintaining their abundance and may be able to achieve a certain equilibrium with rainbows over time. This, along with the observations mentioned above, suggests that rainbows may have no inherent ability to systematically replace brook trout. [/font][/#cc9966]
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