Bats have been flying since mid-April, and now on these warm May evenings, soon after sunset, I like to sit outside our home and watch the neighborhood bats zipping through the air.
The bat is the only mammal capable of true flight. Flying squirrels glide, but they cannot propel themselves upward as bats do. There are bats that eat frogs, some that eat fish, mice, scorpions, birds, or even other bats, and others that focus on fruit or lap blood or sip nectar. There are about 900 species of bats in existence, with the tropics harboring the greatest diversity of bat life. Minnesota, with its complement of seven species, can hardly be considered prime bat country. All of our Minnesota bats are insectivorous; that is, they feed on insects.
Say the word "bat" and many people cringe. The fear and disgust that some people feel toward bats is unfounded. Bats are gentle, intelligent and, contrary to popular belief, rarely transmit rabies.
Bats live a long time, some 20 years or more. Their reproductive rate is correspondingly low. Bats that spend winter in Minnesota breed before hibernating. Bats don't spend much time with courtship rites, and mating is promiscuous and unselective. Females give birth while hanging upside down. Their normal litter size is one. Baby bats are born late in the spring when flying insects are plentiful enough to meet the nutritional needs of a lactating mothers.
The baby clings tightly to its mother's fur during the first few days, even on nightly feeding flights. It grows rapidly, and the mother leaves it hanging behind by the time the baby is 6 or 7 days old. By about four weeks, babies can scarcely be distinguished from adults.
Jim Gilbert did Nature Notes on Sundays on WCCO Radio for more than 40 years. He retired this month. His observations have been part of the Minnesota Weatherguide Environment Calendars since 1977, and he is the author of five books on nature in Minnesota. He taught and worked as a naturalist for 50 years.
