Predation on Pupae of Douglas-fir Tussock Moth, Orgyia pseudotsugata (McDunnough) (Lepidoptera: Lymantriidae)

Abstract
Predation of artificially stocked Douglas-fir tussock moth pupae was 2 to 49% at sites in southern Oregon and the central Sierra Nevada in California, 1976–1979. Predation was primarily by foliage-foraging birds and, to some extent, ants. Mortality caused by these guilds, and by other unidentified predators, varied inversely with natural pupal densities. Estimated prey consumption increased asymptotically, with predation reaching about 0.02/0.65 m 2 of foliage. Results suggest a maximum attainable pupal mortality of <0.1 per unit area of foliage by the predators considered.