The truth about these helpful insect eaters
As we leave Halloween season, one of the most popular images of this spooky time of year is that of a bat. The creepy tales of vampire bats and Dracula are enduring and certainly exciting. Unfortunately, many negative connotations exist around this fascinating species. Perhaps you’ve heard they carry rabies, that they will fly into your hair, or that many of them are considered blood-sucking vampire bats? In fact, there are many benefits to having bats in one’s landscape and neighborhood. The predominant role of bats in our local ecosystem is that of insect predator. A single little brown bat (Myotis lucifugis), which is native to the Florida Panhandle, can eat 1,200 mosquitoes in one hour of feeding. Many species eat moths that would otherwise cause destruction to agricultural crops and home vegetable gardens. Other species in warmer climates eat fruit and play a major role in re-foresting rain forests in Central and South America—after digesting the fruit they leave seeds in their droppings (guano is excellent fertilizer, by the way), helping replant 95% of the very trees they feed upon. Some species feed on nectar, filling the same role as bees and helping pollinate bananas, avocados, cashews, and figs.
Contrary to popular belief, bats are not blind and many have excellent vision. However, they do rely heavily on echolocation to sense prey and are extremely accurate hunters. They often fly erratically because they are chasing very small flying insects, so the only reason one would end up in a person’s hair is if a mosquito flew through it with a bat in chase! While vampire bats do exist, of more than 1,200 species of bats in the world there are only 3 that feed on blood, and they all live in Latin America. They also tend to feed on the blood of livestock. Human contact with bats is rare unless the bats are sick, which is why one found on the ground should be left alone. Rabies transmission from bats accounts for only one death per year in the United States—a statistic much less than that of deaths from dog bites, bee stings, and lighting strikes! In fact, several towns in Texas with the highest populations of bats in the country have recorded zero human bat-transmitted rabies cases.
Bat populations are declining in North America due to disease (particularly white-nose syndrome), loss of habitat, and the slow reproductive cycle of bats. However, you can help the world’s only flying mammal by installing a bat house in your yard. Keep in mind that bats attracted to bat houses prefer to be in open areas away from trees (where their predators hide), and the house should be installed at least 12 feet in the air. Bat houses can be purchased or built rather simply—keep an eye out for Extension workshops near you, or check out the publication “Effective Bat Houses for Florida” online. In addition, Bat Conservation International’s website has a wealth of information on conservation projects worldwide.
Bats can be a beneficial addition to the wildlife community on your property. With the exception of a few uncommon bats in the Florida Keys, all resident bats in Florida eat insects. Bats reduce common insect pests by consuming them in large quantities and the sound of bat calls can repel additional insects from areas where bats spend time. By attracting bats to your farm, forest, or backyard you may substantially reduce the number of nocturnal insects nearby.
Attracting bats to your property
All insect-eating bats need roost sites in which to sleep during the day. Several of the 13 species of bats that live in Florida year-round select warm, dry, dark, narrow crevices for roosting. You may be able to attract these bats to your property by putting up wooden bat houses with appropriately-sized crevices (Figure 1). The two species you are most likely to attract to bat houses in Florida are the Brazilian free-tailed bat (Tadarida brasiliensis) and the evening bat (Nycteceius humeralis). Other less common tenants of bat houses in Florida are the southeastern bat (Myotis austroriparius) and the big brown bat (Eptesicus fuscus). Each of these species consumes insects that are known pests to crops.
Instructions for building bat houses can be found here: http://edis.ifas.ufl.edu/uw290
Information courtesy Carrie Stevenson – Coastal Sustainability Agent, Escambia County Extension Office