Suchergebnisse

Identification and conservation of genetic diversity within and among freshwater fish populations are important to better manage and conserve imperiled species. The Carolina Madtom Noturus furiosus is a small, nongame catfish that is endemic to the Tar and Neuse River basins of North Carolina. Genetic structure has not been studied in the species, and given recent population declines in both basins, identification of remaining genetic diversity within the species is vital for informing conservation efforts. To assess the status and trends of Carolina Madtom genetic structure, we analyzed genetic markers from 173 individuals to (1) define population genetic structure, (2) assess intra- and interbasin genetic differentiation in the Tar and Neuse River basins, and (3) present management implications to guide conservation efforts. Using 10 microsatellite primers developed for the related Yellowfin Madtom N. flavipinnis, we observed low genetic diversity in Carolina Madtoms. Genotype frequencies within samples were not in Hardy-Weinberg equilibrium, with a deficit of heterozygotes that could be due to family structure, inbreeding, or segregation of null alleles. Mean (+/- SD) M-ratios for the Tar River (0.414 +/- 0.117) and Neuse River (0.117 +/- 0.102) basin collections indicated that both populations have experienced recent demographic bottlenecks, with that in the Neuse River basin population being more severe. Effective population size estimates for the respective populations were small, on the order of tens of individuals, driving low genetic diversity within populations. However, the multilocus population differentiation metrics GST ' (mean +/- SE = 0.135 +/- 0.031) and D-EST (0.125 +/- 0.029) were significantly different from zero (P < 0.001), indicating significant genetic differentiation between the Tar and Neuse River basin populations. Our findings will inform managers on the status of genetic variation in the Carolina Madtom and will guide conservation toward protective listing and management decisions to maintain the viability of this important endemic species. ; NCWRC through the State Wildlife Grant Program; Virginia Agricultural Experiment Station under the U.S. Department of Agriculture's National Institute for Food and Agriculture; North Carolina State University; NCWRC; U.S. Geological SurveyUnited States Geological Survey; USFWSUS Fish & Wildlife Service; Wildlife Management Institute ; Published version ; Funding for this research was provided by the NCWRC through the State Wildlife Grant Program. We thank William Wood, Joseph McIver, Spencer Gardner, Tom Fox, Zoe Nichols, and Mike Walter for field and laboratory support. The manuscript was strengthened by attention to the comments of the anonymous peer reviewers. The participation of co-author Eric M. Hallerman was supported in part by the Virginia Agricultural Experiment Station under the U.S. Department of Agriculture's National Institute for Food and Agriculture. The North Carolina Cooperative Fish and Wildlife Research Unit is jointly supported by North Carolina State University, NCWRC, U.S. Geological Survey, USFWS, and Wildlife Management Institute. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. There is no conflict of interest declared in this article. ; Public domain authored by a U.S. government employee