This study examined population dynamics, ecology, genetic diversity, and habitat use of wild Brook Trout in tributaries of the East Branch Ausable River, NY from headwaters to mouth. Brook Trout population abundance was estimated and fish community composition was documented along the longitudinal gradient of the East Branch Ausable River. Brook Trout were found throughout this watershed, and multivariate analysis demonstrates that habitat variables influence community assemblage. In addition to elevation, gradients of forest cover, temperature, and percent impervious surfaces explained variation of fish distribution in this watershed. Population genetic analyses demonstrated that natural reproduction of wild and hatchery fish is occurring in the headwaters. Brook Trout in the headwaters of the Ausable River are an admixed population of wild and domestic-Temiscamie fish, and results show lasting effects of fish stocking on the genetic diversity and population status of this system
