In reality, the threatened animal isn’t dangerous at all. “People are much more likely to get rabies from raccoons and skunks than from bats,” said Tomasi. For example, the bats that inhabit the United States only eat insects, generally weigh less than 15 grams and are about the size of a little finger, but with wings. The biggest bats found in Missouri are less than an ounce. There are bats in the tropics that eat other animals, fruit, nectar and pollen.
Although vampire bats do exist outside the United States, their means of eating is not as violent as stories have led people to believe. In order to eat, vampire bats make a slit, like a small razor blade cut, on the victim and let it bleed. Then they lap up the puddle of blood like a dog. While they are bigger than the bats native to the U.S., they still only weigh about 1-2 ounces.
The main role of bats in the U.S is insect control. “If there were no, bats we’d have more insect problems and probably try to compensate for this by using more pesticides,” said Tomasi.
Tomasi, who is studying the hibernation of bats, said most species only use caves for that purpose. While some use them all year around, others never use caves and instead migrate south for winter or hibernate in the woods.
During hibernation, bats go into a deep state of torpor, a chemically induced stupor. During this time, their body systems slow, and their body temperature cools down. Every 10-14 days they arouse from torpor and their body warms back up. Then a couple of hours later, they go back into torpor. Hibernation is necessary for bats, but it leaves them vulnerable.
According to Tomasi, the bat population is being threatened by a disease that is thought to have been brought to New York about five years ago from Europe. White-nose syndrome is a skin fungus that grows on bats during hibernation. It interferes with a bat’s ability to hibernate; the fungus causes them to burn up their stored fat too quickly and consequently starve to death. The disease is killing bats by the millions. The fungus has been spreading west and made it to the Mississippi River last winter.
Another major threat to the bat population is wind turbines. For a reason researchers have yet to discover, Tomasi said, bats are attracted to them. They fly up close to the turbines and get killed. The bats that migrate outside of caves long distances in the spring and fall seem to be in the most danger.
Since bats only produce one young per year, these new threats are becoming a major problem. Even if the mortality from these threats can be reduced, it will take many years for the populations to build back up.