Diel patterns of predation in potato: A well-balanced story

Nocturnal observations of sentinel prey (Colorado potato beetle eggmasses) in Maryland potato fields encompassed several 48-hour periods through the season, during which several hundred eggmasses were observed every three hours. Predation events occurred during all sample periods, but the majority of predation events occurred after dark, and the fewest were observed during the afternoon hours. The natural enemy complex was dominated by three predator beetles and three predator bugs. Lebia grandis adults are primarily night-active, and their egg consumption exceeded that of the conspicuous mainly diurnal Coleomegilla maculata. Chauliognathus sp. larvae, not previously reported as CPB predators, were almost exclusively active between 2300 and 0800 hours. Bugs (Perillus, Podisus, and Geocoris) were almost exclusively diurnally predatory on CPB eggs. All of these major predators had distinct diel patterns, according to circular statistics tests of uniformity around the 24-hour clock.