Food of the red bat Lasiurus borealis in winter in the great dismal swamp, North Carolina and Virginia

It is generally assumed that during winter insectivorous bats in cold climates hibernate, and thus do not feed, whereas bats in warmer areas remain active and do feed. However, bats often fly about in winter, even in higher latitudes, and it has been assumed that they were feeding, based on bits of chitin in intestines and on the occurrence of feeding buzzes. However little brown (Myotis lucifugus) and northern myotis (M. septentrionalis) and big brown bats (Eptesicus fuscus) flying in winter in central Indiana do not feed. We examined digestive tracts of red bats (Lasiurus borealis) that were collected in winter in The Great Dismal Swamp, about 250 miles S of Indiana in coastal northeastern North Carolina and southeastern Virginia. In contrast to the bats in Indiana, these bats fed throughout the winter. Moths and flies constituted over 90% of the volume of food in 24 individuals.