Forest fragmentation and colony performance of forest tent caterpillar

Abstract

We monitored survival and egg production in colonies of Malacosoma disstria in the understorey to examine relationships between colony performance and forest structure at several spatial scales. As forest cover increased, fewer moths survived. Increased mortality from a virus and a parasitoid assemblage were the main causes of this result. Forest cover measured at the smallest spatial scale (53 × 53 m) was the best predictor of colony performance. We attribute these effects of fragmentation to fine‐scale differences in microclimate betweeen edge and interior habitats (edge effects).