摘要：Central stonerollers (Campostoma anomalum) were collected October 1994 through September 1995 from two third-order, warm-water Tennessee streams, Blackburn Fork and Spring Creek. Total lengths and numbers of externally-visible black-spot cysts were recorded for infected fish. Mean cyst densities, variance-to-mean ratios, and prevalence rates were consistently higher in Blackburn Fork than in Spring Creek. Peaks in prevalence and variance-to-mean ratios from Blackburn Fork occurred in September and January, respectively. Peak prevalence in Spring Creek occurred in October 1994. No trends in variance-to-mean ratios were observed in Spring Creek. Differences in black-spot metapopulations were due to cercarial transmission rates and undetermined abiotic factors.
