Effect of Branch Height on Predation of Western Spruce Budworm (Lepidoptera: Tortricidae) Pupae by Birds and Ants

Birds were as effective in destroying pupae of the western spruce budworm, Choristoneura occidentalis, on branches ca. 20 m above ground as on branches at ca. 2 m. Ants, however, were ineffective against pupae installed on the high branches.