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Park City, TN, United States

Habera J.W.,Tennessee Wildlife Resources Agency | Kulp M.A.,Great Smoky Mountains National Park | Moore S.E.,Great Smoky Mountains National Park | Henry T.B.,University of Plymouth | Henry T.B.,University of Tennessee at Knoxville
North American Journal of Fisheries Management | Year: 2010

We evaluated three-pass depletion sampling for both AC and pulsed-DC electrofishing for estimating the population size of rainbow trout Oncorhynchus mykiss in a representative low-conductivity (20-μS/cm) southern Appalachian stream with limited habitat complexity. Trout capture efficiencies in such streams could be expected to exceed those observed in streams in which habitat is more complex; thus, depletion estimates could be much more accurate in the former. We also compared the results for two trout length-groups to investigate size-related differences. Measured capture efficiency was 0.88 ± 0.04 (95% confidence interval) for trout greater than 100 mm (typically adults) and 0.65 ± 0.09 for trout less than 100 mm (age 0). Population size was underestimated in each depletion sample. The errors for trout over 100 mm were generally small (mean, 12%; range, 3-23%), and the upper 95% confidence limits were usually within 10% of the true population size (N). Underestimates of N were larger for trout under 100 mm (mean, 32%; range, 5-60%), although the upper 95% confidence limits were within 20% of the N for half of the samples. The results of a laboratory study confirmed that trout over 100 mm were immobilized at significantly lower voltage gradients than were smaller trout in both electric fields. We conclude that three-pass depletion sampling is relatively accurate in typical southern Appalachian trout streams and that the underestimation errors for rainbow trout larger than 100 mm would be acceptable given basic inventory and monitoring goals. © American Fisheries Society 2010. Source


Hakeem A.,University of Tennessee at Knoxville | Grant J.F.,University of Tennessee at Knoxville | Lambdin P.L.,University of Tennessee at Knoxville | Buckley D.,University of Tennessee at Knoxville | And 4 more authors.
Biocontrol Science and Technology | Year: 2010

Eastern hemlock in the Great Smoky Mountains National Park is currently threatened by the hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae). As part of a management plan against this invasive insect pest, about 350,000 adults of the predatory beetle Sasajiscymnus tsugae (Sasaji and McClure) (Coleoptera: Coccinellidae) were released at ca. 150 sites in the Park from 2002 to 2007. Of these adult release sites, 33 were sampled in 2008 and 2009 using beat-sheet sampling for 4 man-hours. Sasajiscymnus tsugae adults (n = 78) and/or larvae (n = 145) were recovered from seven sites (21.2% of the release sites sampled). Recovery of S. tsugae was significantly associated with older release sites, with the most beetles recovered from 2002 release sites. These results indicate that S. tsugae may require more time (i.e., 5-7 years) than anticipated for population densities to reach readily detectable levels in some areas. Source


Hakeem A.,University of Tennessee at Knoxville | Hakeem A.,Texas AgriLife Research Center | Grant J.F.,University of Tennessee at Knoxville | Wiggins G.J.,University of Tennessee at Knoxville | And 6 more authors.
Environmental Entomology | Year: 2013

ABSTRACT To reduce populations of hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), >500,000 Sasajiscymnus tsugae (Sasaji and McClure) (Coleoptera: Coccinellidae) have been released in the Great Smoky Mountains National Park since 2002. To determine factors affecting establishment and recovery of these predatory beetles, 65 single release sites were sampled using beat sheets from 2008 to 2012. Several abiotic and biotic factors were evaluated for their association with establishment and recovery of S. tsugae. Information on predatory beetle releases (location, year of release, number released, and season of release), topographic features (elevation, slope, Beers transformed aspect, and topographic relative moisture index), and temperature data (minimum and maximum temperatures 1 d after release and average minimum and maximum temperatures 7 d after release) were obtained from Great Smoky Mountains National Park personnel. These factors were evaluated using stepwise logistic regression and Pearson correlation. S. tsugae was recovered from 13 sites 2 to 10 yr after release, and the greatest number was recovered from 2002 release sites. Regression indicated establishment and recovery was negatively associated with year of release and positively associated with the average maximum temperature 7 d after release and elevation (generally, recovery increased as temperatures increased). Several significant correlations were found between presence and number of S. tsugae and year of release, season of release, and temperature variables. These results indicate that releases of S. tsugae should be made in warmer (≈10-25°C) temperatures and monitored for at least 5 yr after releases to enhance establishment and recovery efforts. © 2013 Entomological Society of America. Source


Gibbs W.K.,Tennessee Technological University | Miller J.E.,Tennessee Technological University | Cook S.B.,Tennessee Technological University | Kulp M.A.,Great Smoky Mountains National Park
Southeastern Naturalist | Year: 2014

Etheostoma sitikuense (Citico Darter), a federally protected fish endemic to the southeastern United States, was extirpated from Abrams Creek in Great Smoky Mountains National Park in 1957. The species was reintroduced from 1993-2001, but recovery efforts have thus far achieved only partial success, due in part to limited knowledge of Citico Darter habitat use. After distribution of the reintroduced population was established, we monitored Citico Darters in a 4-km section of Abrams Creek using underwater observation. We evaluated macro-and microhabitat use over four summers using principal components analysis to determine macrohabitat variables influencing Citico Darter distribution, and used classification tree methods to analyze microhabitat use. We analyzed dispersal using linear regression to compare historical stocking data with current Citico Darter distribution data. We identified percentage of pools and cobble/small boulder substrates as the most significant macrohabitat variables influencing Citico Darter presence. This species most often occupied microhabitats away from riffles under intermediate-sized cover rocks. Dispersal of reintroduced Citico Darters was limited in Abrams Creek. Results of this study can be used to identify additional reintroduction zones and assist in further conservation efforts. Source


Gibbs W.K.,Tennessee Technological University | Cook S.B.,Tennessee Technological University | Kulp M.A.,Great Smoky Mountains National Park
Journal of Freshwater Ecology | Year: 2014

Habitat use by smoky madtoms (Noturus baileyi) and yellowfin madtoms (Noturus flavipinnis) was quantified in lower Abrams Creek within the Great Smoky Mountains National Park during the summers of 2007-2010. Variables were measured at both macrohabitat and microhabitat spatial scales within locations where each species was present. Reach-level macrohabitat data were analyzed using principal component analysis to identify variables associated with each species presence within a reach. Classification trees were developed to describe microhabitat use for each species and to compare differences in microhabitat use between species. Distributions of both species were similar in lower Abrams Creek with each becoming more abundant within downstream reaches. Smoky madtoms predominantly used riffle and run microhabitats with gravel and cobble basal substrates, while yellowfin madtoms used pool microhabitats away from riffles with low velocity and cobble-sized cover rocks. Neither species was ever encountered within the same microhabitat, suggesting summer habitats were partitioned. Models developed in this study can be used to identify potential reintroduction zones or to assist in conservation efforts. © 2014 © 2014 Taylor & Francis. Source

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