EFFECTS OF PHOTOPERIOD AND SIZE ON FLIGHT ACTIVITY AND OVIPOSITION IN THE EASTERN SPRUCE BUDWORM (LEPIDOPTERA: TORTRICIDAE)

Abstract

Well-fed, mated female spruce budworm (Choristoneura fumiferana (Clem.)) show little activity during the first 24 h after emergence. During the second 24 h they lay between 33 and 50% of their egg complement. During the third 24 h most flight activity occurs. Smaller, artificially starved females are much more active, especially during the second 24-h period, when many fly before ovipositing. Timing of oviposition and flight is under photoperiodic control: female flight occurs just before dark after peak oviposition while male activity starts before dark, but peaks after dark, with a morning peak of variable intensity.