Seasonal Migration by Red-Backed Salamanders, Plethodon cinereus

We report direct observation of seasonal movements of adult Plethodon cinereus uphill to a rocky hilltop in the fall and downhill into a wet area in the spring. Counts from arrays of cover boards in both areas showed occupancy patterns that were consistent with seasonal changes in spatial distribution. Soil moisture was markedly higher and pH was slightly lower in the downhill area. Soil temperature did not differ between the two areas. Young age classes do not migrate but apparently stay in the wet area where they hatch. Differences in body size and egg diameter between fall and spring samples suggest that migratory adult salamanders grow and yolk eggs during the winter. The most likely explanation for this behavior is that the rocky hillside provides crevices that allow salamanders to get far enough underground to remain active in winter.