The genetic structure of coastal giant salamanders (Dicamptodon tenebrosus) in a managed forest

The salamander, Dicamptodon tenebrosus, is threatened by habitat loss and fragmentation associated with forest harvest activities. We used three microsatellite loci and 38 amplified fragment length polymorphisms (AFLPs) to quantify population structure and indirectly evaluate the impacts of forest harvesting on this species. We sampled two old growth sites, three second growth sites and three recently clearcut sites in British Columbia, Canada. Microsatellite allelic richness and the percentage of polymorphic AFLPs were positively correlated with the age of forest stands. Similarly, heterozygosity estimated from both marker types was positively correlated with stand age. Population subdivision (F-st) estimated among forested sites using microsatellite and AFLP markers was 0.033 and 0.095, respectively. Lower genetic variation and heterozygosity in recent clearcuts suggest that clearcut logging may be associated with local population declines. Our genetic findings are consistent with previous studies that report lower salamander densities in recently clearcut sites. (C) 2003 Elsevier Ltd. All rights reserved.