Mortality and viability of insect migrants high in the air

Entomologists have long been aware that vast numbers of insects are distributed up to thousands of feet in the air on any warm day. The men who collected evidence of this assumed that the insects were alive. However, the trapping methods they used killed most of the insects so that mortality and viability could not be assessed. Other entomologists have been less confident of the vitality of insects dispersing regularly by such flights, perhaps because of a belief that an ascent to, say, 5,000 ft. means a flight of many hours; this is not necessarily so. Nevertheless, it is not generally accepted that this mode of transport is no more lethal than flight near the ground. RESP-4253