Bats and their Ways

Abstract

ON p. 46 of this issue, Dr. Donald R. Griffin deals with the extension of the work he did, in association with Dr. Robert Galambos, on the supersonic cries of bats. In the July issue of the National Geographic Magazine, Dr. Griffin gives a descriptive account of his work on bats, with several excellent photographs showing the winter haunts of bats, their movements in flight and the laboratory equipment devised to test their power of avoiding obstacles. During his investigations, which have extended over the past fourteen years, Dr. Griffin has given particular attention to bats of New England, including many species of the little brown bats (Myotis), pipistrelles (Pipistrellus subflavus and related species) and the big brown bat (Eptesicus f. fuscus). Some 13,000 bats have been marked with aluminium bird bands, from the recovery of which it has been ascertained that they have good powers of homing ; and although the 'cave bats', as they are termed, hibernate, they also are known to migrate distances up to 150-170 miles to find, or return to, suitable winter quarters- often disused mine-workings and limestone caves. The use of the high-speed camera with simultaneous cinematograph pictures shows that, when flying, bats make about fifteen strokes of the wing each second and that their flying speed is approximately 10 miles an hour.