Incidence of Parasitoids Attacking Endemic Spruce Budworm (Lepidoptera: Tortricidae) Populations in New Brunswick

Annual population estimates of spruce budworm, Choristoneura fumiferana (Clem.), larvae and the incidence of larval parasitism were monitored in northern New Brunswick following the collapse of the 1949–1959 epidemic in the region. The most common parasitoid among the very sparse hosts was Synetaeris tenuifemur, although it had been rarely found during the epidemic. Larval parasitism sometimes exceeded 50% but it could not be shown as a key factor associated with changing host abundance.