Bats are our friends.

In the last issue, a correspondent described how interesting life can be when you have about 1,000 bats in your house. We braced ourselves for a barrage of outrage from bat lovers.

Interestingly, however, we received the following article from Suzann C. Rensel even before that issue went to press.

Anyone concerned about the quality of the food we grow and the effect diet has on our health appreciates finding alternatives to pesticides. Many people have realized the benefits of attracting insect-eating birds to our backyards and using companion planting. However, research from the past 25 years is showing yet another, and perhaps the most valuable economically, bug control agent. This highly developed order of mammals could help us see our way to healthier crops if we can overcome the myths and fears surrounding them. These mammals are bats.

Until recently, no one knew much about bats; in fact, most of what we thought we knew was based on myths and fears, no thanks to the big screen's popular bad guy, Count Dracula. (Of the 44 species of bats which reside in the United States, not a one is a vampire bat. Vampire bats live in Central and South America only.)

Most U.S. bats are insectivores. They prey mostly on night flying insects. A large portion of these nocturnal "bugs" are well known and greatly despised crop pests. For example, cucumber beetles infest vining plants and spinach, and their larvae target the roots of corn, (corn rootworms). big brown bats, Eptesicus fuscus, find the adult stage of these beetles quite tasty. Their diets include other pests which attack our vineyards, orchards, and gardens, such as June bugs, stink bugs, and leafhoppers.

A popular entree for the common little brown bat, Myotis lucifugus, is the moth whose larval stage is known as the corn earworm. These are those brown caterpillars we find as we peel off the husks of sweet corn and which often beat us to the first succulent bites of corn each summer.

Before many of us in the northern states have a chance to begin preparing the garden for our crops, bats have returned from their winter hibernacula or their southern wintering grounds (not all bats hibernate). By April they have begun to feed. So as much as a month before our spades hit the dirt, bats may be preventing an infestation of June bug larvae, grub worms. The positive impact bats can have on crops is truly amazing.

Try to imagine the last time you saw a bat flutter through the night. You may have seen it swoop to snatch an insect. If that insect was a female cucumber beetle, you may have witnessed the prevention of 100 corn root worms attacking your corn. Since insectivorous bats consume approximately one half their weight in food, a bat eats an average of 1/4 ounce of insects each night. Definitely more than one cucumber beetle!

John O. Whitaker, Jr., Professor of Life Sciences at Indiana State University, estimates in his article, "Food of the big brown bat Eptesicus fuscus from maternity colonies in Indiana and Illinois," that a colony of 150 big brown bats could eat enough cucumber beetles to equal "the potential destruction of 33,000,000 rootworms."

Unfortunately, beneficial bats like these have suffered from greater misconceptions than the vampire scare, resulting in a decline of bat populations. Many people believed that bats were rodents, multiplying in large quantities. In actuality, bats reproduce only once a year with the majority of species having a single offspring per mother. This fallacy may have originated because some bats are colonial, meaning they roost in large numbers.

Some species, such as the little brown bat, the gray bat and the Indiana bat, cluster in caves during hibernation also. As many as 200 little brown bats can occupy one square foot of a cave wall! Imagine the increase of corn ear moths that would result from an uneducated intruder in that cave maliciously swinging a three foot ball bat at sleeping little brown bats.

Hibernating or active, bats do not want to nest in our hair. As already stated, bats eat bugs and bugs are attracted to lights. If we are outside at night, most of us are near a light. The bugs come to the light and the bats follow the bugs. Besides, bats do not build nests.

While they utilize echo location for finding food, bats can see, they are not blind. Their eyesight rivals our own. This is great for seeing during the day, but trying to detect a small insect, like a delicious mosquito, at night requires the use of their built-in sonar.

A common fear associated with bats is rabies. Bats are warm blooded animals; therefore they have the potential to carry the rabies virus. But they are not the source of rabies. They are victims, as is any animal which contracts the virus. Furthermore if a bat does contract rabies, it does not act like the majority of other animals that become aggressive. A bat will become lethargic and not fly. This actually further decreases the chance of an encounter with a rabid bat. Just follow the same rules you do with all wildlife; namely, leave them to themselves, do not handle them, and since cats are predators of bats and may attack a resting bat, immunize your pets.

Once we get past these fears and misconceptions, we can understand the important niche bats fill in our environment. If you are fortunate enough to have a colony of bats living in an outbuilding, you are already enjoying the benefits of these natural bug zappers. If you want to attract bats to your yard or farm, bat boxes may be what you need.

Bat boxes perform the same function as bluebird boxes, namely providing a home to animals whose natural residences have been altered by humans. Bat boxes have an open entrance at the bottom with slats inside between which the bats roost. They come in a variety of sizes and can be used to attract bats and remove unwanted colonies from human homes without exterminating this vital animal.

To attract bats you must first determine what their needs are and how you can meet those needs. Doing a little research to discover which bats live in your area is a good way to begin assessing those needs. Your state wildlife agency is a good place to start. However, state publications may be outdated. More recent information is often available from universities and don't forget about your local library or nature center.

Once you know which bats you are trying to attract, you can match them to the most appropriate bat box design. For instance, some bats prefer the slats inside the box to be 3/4 of an inch apart but others prefer a space of an inch or more. Northern bat boxes need greater exposure to afternoon sun in order to ensure optimum temperatures while some southern bat species prefer afternoon shade.

For additional data and if you are interested in networking with other bat box owners, contact Bat Conservation International. They have information available on bats, and box studies done across the country. Through their North American Bat House Research Project they hope to study the use of bat houses combined with lights over crops as a method of organic farming. (See article at left.)

As predators of cucumber and potato beetles, grain moths and cutworms, bats are valuable, native, and natural control agents. Understanding the needs, truths, and ecological roles of bats can lead to less dependency on chemical pesticides--meaning less expense, less soil and water contamination, and fewer hazards to our health.