Most people know that bats are mammals. But few realize that Bats account for about 20% of all mammal species. Bats are found in all parts of the world except the Arctic. There are more than 1200 species of bats and 45 are present in the United States. Bats are the only mammal capable of true flight. Bats usually live an average of 4-10 years but some live up to 20.
Contrary to popular belief, bats are not blind. They possess functional eyes which are used for long distance orientation and object identification. In fact the visual acuity of Bats is considered fairly good. Bats do have sonar, however. Bats forage for food by emitting a continuous stream of high pitched sounds (Echolocation) audible only to other bats. This ability is so sensitive that it can detect objects as thin as a single human hair. In addition to bats; shrews, dolphins, and some cave dwelling birds use sonar to hunt for prey also.
About 70% of all bats are insectivores. Bat colonies save billions of dollars per year in agricultural pest control. A single bat can eat 600 bugs per hours. It is recognized that Humans could not control the insect population without bats. Some bats live off of blood; however they do not actually suck the blood. They use their razor sharp teeth to make a small incision in the skin of a sleeping animal and then consume the blood as it runs from the wound. They require approximately two tablespoons of blood a day. The saliva of bats has a similar anesthetic quality to that of mosquitoes. This helps to prevent the animal from feeling the cut and seldom causes harm.
Bats sleep and hang upside down. Unlike humans, a bat’s circulatory system pumps the opposite way – away from its head. It also conserves energy for the bat in that it doesn’t have to hold itself up. Female bats are able to control when they get pregnant and give birth. They are equipped with a variety of biological tactics that allow them to postpone fertilization, implantation or development of the fetus.
Bats often share their home with thousands or even millions of other bats. The world’s largest natural bat colony is the Bracken Bat Cave in Texas which houses 20 million bats. In one night this entire colony can consume 200 tons of bugs. The world’s largest urban bat colony is in Austin, Texas under the Ann W. Richards Congress Ave. Bridge. This is home to 1.5 million bats.
The beneficial value of bats cannot be overstated. Scientist are very concerned for the future of bats. There are real issues facing bats with habitat loss and emerging disease. In February of 2006 in Howe Caverns near Albany, New York a fungus called White Nose Syndrome was discovered. This fungus accumulates around the muzzles of hibernating bats. This disease spreads rapidly and is now known to exist in 115 bat colonies across the eastern half of North America. It is also moving quickly towards the west. It has a 95% mortality rate and is responsible for the death of over 6 million bats in 6 years.