FOREST FRAGMENTATION AND COLONY PERFORMANCE OF FOREST TENT CATERPILLAR

We monitored survival and egg production in colonies of Malacosoma dis stria in the understorey to examine relationships between colony perfo rmance 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 c over measured at the smallest spatial scale (53 x 53 m) was the best p redictor of colony performance. We attribute these effects of fragment ation to fine-scale differences in microclimate betweeen edge and inte rior habitats (edge effects).