Dale Evva Gelfand - Building Bat Houses

Dale Evva Gelfand

Why, you may be asking yourself, would anyone want to build a bat house?

Mention the word bat, and the image that springs to mind for most people is of a bizarre flying beast, a vicious creature fangs bared, ready to turn into Dracula, spread rabies, or, at the very least, get tangled in your hair.

While its true that a number of species of bats have some odd characteristics, the unsavory reputation saddled upon these peaceful mammals is the result of age-old myths, fables, and misconceptions. To this day, bats are frequently associated with witchcraft, vampires, and haunted houses, and their fearsome reputation remains unshakable. Its also unjustified. Not only are bats not blood-thirsty, they are, in fact, beneficial to human civilization.

Bats rid the world of billions of insect pests every night, and they act as pollinators and seed dispersers for many different plants. But because bats have been so badly and wrongly maligned, whole colonies are still routinely eliminated. In the United States alone, more than 50 percent of our resident bat species are either declining rapidly or listed as endangered. Much of this decrease in bat numbers can be directly attributed to adverse human intervention, be it through direct killing of the animals as a result of ignorance or cruelty, the use of pesticides on their food supply, or the destruction of their habitat. Even unintentional or well-meant disturbances from spelunkers inadvertently exploring bats caves or biologists deliberately entering bats domains to study their habits and habitats can have severely detrimental effects on hibernating or maternity colonies.

For this reason, there is a growing movement to preserve natural bat habitats or to provide them with artificial roosting sites. Thanks to efforts by conservationists, both governmental and private organizations (foremost among the latter being Bat Conservation International BCI a Texas-based nonprofit organization dedicated to bat conservation, research, and public education), more and more people are now willing, even eager, for bats to make nightly forays into their backyards. An excellent way to make neighborhoods attractive to bats is to provide artificial habitats to augment the decreasing natural ones. Besides, its only right that since bats do so much for us, we do something for them in return.

Bats are the primary predator of night-flying insects, from mosquitoes that spread disease (not to mention annoyance) to codling moths that attack apple trees and bollworm moths that feast on cotton plants. In fact, in some areas the moths that feed on farm crops make up 90 percent of a bats diet; in others, the control of malaria has been aided by the resident bat populations diet of mosquitoes.

Big Brown Bats (thats the species name, not just its description), which live primarily in agricultural areas, feed on June bugs, cucumber beetles, stinkbugs, corn rootworms, grasshoppers, and leafhoppers. Over the course of one summer, a colony of 150 Big Brown Bats will dispatch 38,000 cucumber beetles, 16,000 June bugs, 19,000 stinkbugs, and 50,000 leafhoppers while preventing 18 million corn rootworms from ever seeing the light of day by consuming the beetle stage of this insect pest.

The Little Brown Bat, on the other hand, is a prodigious consumer of mosquitoes. A single Little Brown Bat can eat some 500 mosquitoes in just one hours time, or nearly 3,000 every night (a bat may consume nearly 50 percent of its body weight in insects nightly); a colony of 100 will likely ingest more than 250,000 mosquitoes a night. Forest-dwelling bats are crucial to maintaining ecosystem health, controlling such pests as tent caterpillar moths that in their larval, caterpillar stage would otherwise defoliate huge swaths of forest.