Beyond the myths and folklore, bats rank among the most beneficial animals worldwide and are most certainly the most misunderstood. They are nature's insect control! Almost all United States bats, and 70 percent of the bat species worldwide, feed almost exclusively on insects. In fact, bats are the only major predators of night-flying insects. One bat can eat between 600 and 1,000 mosquitoes and other insect pests in just one hour!

Phoenix Zoo

Lesser false vampire bat

Bats are mammals that belong to the order Chiroptera (ky-rop-tera), which means "winged hand." The bones present in a bat's wing are the same as those of the human arm and hand, but bat finger bones are greatly elongated and connected by a double membrane of skin to form the wing. Bats are the only true flying mammals and their maneuverability while capturing insects on the wing is astonishing. Doppler radar measurements indicate that bats fly about 6.5 to 49.2 feet per second.

Most bats differ from other flying animals in their reliance on hearing for navigation. While birds have large eyes and keen sight, many bats have a poor sense of vision, and must rely on a superbly developed echolocation (or sonar) system to navigate and capture insects in the dark. Bats that use echolocation usually have large ears and leaf-shaped flaps of skin on their noses. This helps them direct the high frequency sounds they make. Bats emit pulses of very high-frequency sound (inaudible to human ears) at a rate of a few to 200 per second. By listening to the echoes reflected back to them, they can discern objects in their path. Their echolocation ability is so acute they can avoid obstacles no wider than a piece of thread and capture tiny flying insects, even in complete darkness.

Worldwide, bats vary in size from only slightly over 0.07 ounces (about the weight of a dime) to more than more than 3 pounds. The large "flying foxes" of Africa, Asia, Australia, and many Pacific islands may have a wingspan up to 6 feet. Bats primarily are nocturnal, although many fly early in the evening, sometime before sunset. Occasionally, especially on warm winter days, they are observed flying during daylight hours.

Despite their resemblance to rodents, bats are not closely related to mice at all. Though their exact placement is still uncertain, there is recent evidence that they may be more closely related to primates. Whatever their relationships, bats are among the most successful groups of mammals: there are nearly 1,000 species of bats around the world, making up about one quarter of all mammal species. There are two main groups of bats -- the large "flying foxes" that eat fruit, and the smaller insect-eating bats. There are also bats that feed on the nectar of flowers, and those that eat small animals, like fish and frogs.

Phoenix Zoo

Indian flying fox

Throughout the tropics, seed dispersal and pollination activities by bats are vital to rain forest survival. In addition, studies of bats have contributed to medical advances including the development of navigational aids for the blind. Bat droppings, or Guano, is highly prized as an effective fertilizer due to its high levels of phosphorus and nitrogen. Soil that is deficient in organic matter can be made much more productive by addition of this manure. Bat droppings in caves support whole ecosystems of unique organisms, including bacteria useful in detoxifying wastes, improving detergents, and producing gasohol and antibiotics. Therefore, the loss of bats increases demand for chemical pesticides, can jeopardize whole ecosystems of other animal and plant species, and can harm human economies. In fact, a colony of 150 big brown bats can protect local farmers from up to 18 million or more rootworms each summer.

Interesting bat tidbits:

* Bats vary in social structure; some lead a solitary life whereas others live in caves with more than a million total bats. About 70 percent of bats born in any year do not survive their first winter.

* Litter size is usually one; a few species bear twins some of the time. Another few species, especially red bats, have litters of three or four.

* Compared to their mothers, newborn bats are huge! Single young are 25 to 30 percent of their mother's postpartum mass.

* Bats live relatively long lives for animals of their small size, some as long as 30 years.

* Bats are exceptionally vulnerable to extinction, in part because they are the slowest reproducing mammals on earth for their size, most only producing only one young annually.

* Every summer night, hundreds of people gather to see the world's largest urban bat colony emerge from under the Congress Avenue Bridge in Austin, Texas. With up to 1.5 million bats spiraling into the summer skies, Austin now has one of the most unusual and fascinating tourist attractions anywhere. Austin's bridge bats are Mexican free-tailed bats.