Aerobiology of predator and prey: bats and insects

Insect pests cause crop losses and associated pest management costs, but the contribution of beneficial organisms to pest management is poorly understood. Large maternity colonies of Brazilian free-tailed bats, Tadarida brasiliensis, populate caves, bridges, and buildings in central Texas and consume substantial quantities of insects including adult bollworms, tobacco budworms, fall armyworms, beet armyworms and other economically-important crop pests. The objective of this research was to quantify seasonal production of cotton insect pests in the Texas Winter Garden and the availability of insects as a food source for free-tailed bats. Seasonal surveys of all growth stages of four major cotton pests (bollworms, tobacco budworms, fall armyworms, and beet armyworms) were conducted in the Texas Winter Garden production area in 2004 and 2005. Insect and bat flight activity at approximately 3 m above a cotton canopy was monitored by reflective infrared videography during peak emergence of moths from corn fields and expected moth immigration and egg laying in adjacent cotton fields. Video counts of flying moths and bats will be related to prevailing atmospheric factors to describe patterns of pest abundance and bat foraging.