Batty Ideas for Conservation
CJ Brinlee, Soil Conservationist Student Trainee, USDA-NRCS

      Of the many nocturnal creatures perhaps none are so famed or feared as bats. Hailing from the order Chiroptera, meaning “hand-winged”, bats present themselves as the second most specious mammal next to rodents with more than 920 varieties worldwide. Here in the U.S. they are one of the least studied and most misunderstood mammalian species, and due to this have suffered greatly at human hands. At least 40% of American bat species are in decline or listed as endangered. Human ignorance, fear, myth, and habitat destruction has led to the demise of these interesting and beneficial little animals.

      Bats have developed a nasty reputation over the years that has generally led to a decline in the natural bat population. Despite the widespread opinions that bats are deadly carriers of rabies that fly around biting people and spreading disease, these tiny creatures are actually quite docile. Being shy and wary of humans in general, even a rabid bat is not inclined to bite a person unless manhandled. There are three varieties of vampire bats in the world, all of which reside in Central and South America and definitely not in Texas. Moreover, rabies kills bats more rapidly than it does dogs or cats, and often before they ever reach the vicious stage. Even then only about 1% of all North American bats carry rabies.

      In spite of their reputation, these furry flying mammals actually provide more benefit than detriment. They are globally important as pollinators and for seed distribution, but they are more widely known for their usefulness in insect control. Their decline, however, has had negative impacts on the environment. Economically, the destruction of bats can lead to increased crop damage due to insects and cause loss for farmers and higher prices for consumers. Environmentally, the increased use of pesticides, and the loss of a key pollinator and seed distributor can threaten an entire ecosystem.

      However, it is not too late to restore the dignity of the bat. Being as Texas has one of the greatest concentrations of bat species in the U.S., it is our responsibility to take care that these night-flying critters don’t disappear forever. Many key habitats are already in existence in this area, the one thing bats lack the most are proper roosting sites. But before you decide against inviting a family of bats to live on your land, consider some of the benefits you might receive from having a colony of bats as your neighbors.

      We all know that everything is bigger in Texas and especially the mosquitoes. With all the rain this year we’ve been having a plague of these flying pests swarming around our land and homes. While bats feed on all flying insects and not just mosquitoes, they do represent a natural control method that can reduce the mosquito population in your area. Moreover, they tend to feed upon all manner of agricultural pests as well, cutting back on the need to apply pesticides to your crops which can save a farmer time and money. In short, living with bats can be good for both parties.

      The best way to invite a colony of bats to move in is to construct bat boxes, and place them near suitable habitat and feeding areas. Bat boxes can be constructed of most woods, except pressure treated wood, and the roughening of the partition surfaces within the bat box is necessary to provide foot holds for the bats to roost. The exterior of the house should be painted a light brown, caulked to prevent drafts from disturbing the colony, and vents should be cut in the bottom third of the house to prevent it from warming too quickly during the day. When possible, bat houses in this region should be constructed with an aluminum roof providing an overhang to shade a portion of the bat house during the hottest hours of the day. Larger, taller houses are more effective than smaller ones, but dimension can be adjusted to suit the habitat or structure in which a house is placed. The internal roosting crevices should be at least ¾ to 1 inch wide and the partitions can be held in place with grooves in the ceiling and walls, or by 1 inch spacers.

      Bat houses should be placed on poles, or attached to dead trees that receive ample sunlight, or the sides of buildings. They should hang 12-15 feet over the ground to allow entry and discourage predators, and they should face east or southeast and receive at least 4-6 hours of sunlight a day. When placed within a ¼ mile of water, bat houses have a greater chance of occupancy, and should also be surrounded by areas of mixed vegetation type to provide quality habitat, especially including crops or hay pastures where they hunt. These bat houses are designed to attract maternity colonies during the summer, and generally will not be occupied through the winter.

      The key to a good bat house is maintaining suitable internal temperatures. A process called pairing, placing at least two boxes in the same general vicinity, is suggested to provide this so that the colony can move from house to house at different times of the season. If a bat house remains unoccupied for two or three seasons, it is probably not achieving suitable temperatures and should be recaulked or repainted. Like any bird house, bat houses require annual maintenance and cleaning.

      Although this may seem like a lot of trouble to go to simply to attract an animal you may consider a pest, just think that your efforts could be benefiting a declining or endangered species. In actuality, unless bats have taken up occupancy in your home which they will not tend to do if alternate roosting is available and the proper precautions are taken, they are not considered pests at all and can be a source of entertainment as they swoop and dive on the hunt. For more information on how to construct a bat house, visit www.batcon.org, or contact the USDA-NRCS office located at 200 E First Street, RM 14, Bonham, TX. You may call us at 903-583-9513 x3 or email: randy.moore@tx.usda.gov.