Developed by our Ecology and Natural Resources program, the “Wondering About Wildlife?” blog series provides answers to frequently asked questions and concerns about the wildlife around us. This blog focuses on how to manage bats if found in your structures or near your home.
Florida’s Bats
Florida is home to 13 native species of bats. Eleven of our native bat species are considered species of greatest conservation need, with two of these listed as federally endangered, the endemic Florida bonneted bat (Eumops floridanus) and the gray bat (Myotis grisescens). Some of the most common bat species found in the Sunshine State include the Brazilian free-tailed bat, Southeastern myotis, evening bat, Eastern red bat, Seminole bat, and Northern yellow bat. Worldwide bat populations are declining, and all bat species in Florida are protected by law. Bats stand out as the only mammals capable of true flight and for using echolocation as an adaptation to navigate their nocturnal environments.
The Essential Role of Bats: Pest Control
Bats play an essential role in our ecosystems. One of their most valuable contributions is serving as nature’s pest control. All of Florida’s native bat species are insectivores, meaning their diet consists solely of insects. Each night, bats devour an amazing amount of insects, up to 25-100% of their body weight, providing an estimated $3.7 billion worth of natural pest control annually within the United States (Boyles, J., et al., 2011). Their presence leads to a decline in insect pests, thereby mitigating crop damage and reducing pesticide application. But their contributions don’t stop there! Bats in other parts of the world play pivotal roles in pollination and seed dispersal for various plants.
Living With Bats: Exclusionary Techniques
In Florida, it is illegal to harm or kill bats, therefore the use of pesticides or poisons to eliminate bats from a structure is strictly prohibited. The most effective and long-lasting method for removing bats from unwanted areas is exclusion. To ensure successful exclusion, it is important to identify where bats are entering the building, use appropriate exclusionary methods outside of bat maternity season, followed by sealing those entries immediately after exclusion is complete. Bats can enter anywhere there is an opening that your thumb could fit. They especially like gaps between shutters and homes, walls and soffits or ceilings, and between columns and horizontal beams.
Excluding a single bat
Open up all the windows and doors to the outside, close the doors into the house, wait for nighttime and if the bat hasn’t already left on its own, turn on the lights in the room. Generally the bat will find its way out without any help. If you try to use a broom to shoo the bat out, it is likely to fly around trying to escape, increasing risk for interaction. Instead, a broom can be used to allow the bat to crawl onto the wide end and then move the broom carefully outside, prop against a wall or tree, allowing the bat to fly away when ready. Bats on the floor or ground may not be able to fly, as they need to have space to drop down in order to take flight. Allowing them to crawl onto a broom, or using a shovel to gently pick them up and put them gently in or near a tree where they can crawl up and take flight is much safer than trying to pick them up. Never touch a bat. If absolutely necessary to pick a bat up, do so with a towel gently placed over the bat and while wearing thick leather gloves to protect yourself from being bitten.
If there is a bat on the side of your building, in your pool umbrella, or other places where it can easily escape, it will likely fly away once it is nighttime.
Excluding a colony of bats
Check for signs of bat entry and exit points along your structure by looking for dark areas stained by their body oils or guano, and by looking for small areas where bats may be getting in. Once potential entry points are identified, watch those areas at sunset to see if any bats emerge.
There are a number of exclusionary methods that can be utilized depending on the situation and structure. Exclusionary measures allow bats to leave without having a way to re-enter the structure. These methods can only be installed from August 16 to April 14, and when you have four forecast days above 50ºF at night. You must leave the exclusion technique up during those four nights. Installing exclusion measures during the maternity season, which spans from April 15 to August 15, is against the law. This is because such measures can inadvertently trap and harm baby bats, resulting in their starvation and death. Excluding adult bats without allowing them to exit the structure, traps them and can cause them to try to find a way into your home or structure, or causes death, leading to unpleasant odors and pest-related problems.
Netting, mesh, and tubes properly installed will allow bats to exit but not re-enter the building. Mothballs, poisons, ultrasonic sound makers, motion sensor lights, bat baits and repellents are ineffective and may contain chemicals which are toxic. Watch the video below to learn more about proper exclusionary techniques and how to install them. After exclusion is complete, secure openings by fitting doors, windows, soffits, and vents with screens and proper framing, capping chimneys, and sealing gaps around utility lines.
Bat houses are a great way to provide manmade habitat for bats. When constructed and installed appropriately, bat houses provide a place for bats to relocate. For more information on bat houses, read Effective Bat Houses for Florida.
Living with Bats: Safely Co-exist
If visiting an area with bats, or installing a bat house, watch bats from a distance so as not to disturb them and to give them space. Do not stand directly under a bat house. Guano (excrement) from bats is great organic fertilizer, but in enclosed spaces can transmit histoplasmosis when aerosolized.
If you need to clean an area previously inhabited by bats, contact a professional or make sure that you use protective rubber gloves and respirator or mask. Moisten guano to decrease aerosolized particles, and clean area with a disinfectant, such as bleach. Do not reuse cleaning rags.
Never pick up an injured, seemingly ill or dead bat. It is rare in Florida for bats to carry rabies, but possible (~0.5% of Florida bats carry rabies). Rabies is contracted through direct contact with bodily fluids of an infected species. Bats have tiny, sharp teeth and it is possible to be bitten without realizing it. Bats with rabies are not aggressive, so infected bats will generally just get sick and die. It is always best to be cautious if you find a sick or dead bat, or one on the ground. If you think you have been bitten by a bat, contact your local Department of Health to have the bat tested, and seek medical attention immediately.
If you come across unusually behaving or dead bats, report it to the Florida Fish and Wildlife Conservation Commission. For assistance with injured bats, contact the Wildlife Center of Southwest Florida.
To Learn More:
Watch Nature Knowledge- Bats in Florida with Shelly Johnson, UF IFAS Extension State Specialized Agent in Natural Resources.
Read Integrated Pest Management in the Home: Has Your House Gone Batty? Facts about Bats
Check out all the blogs in the “Wondering About Wildlife?” series
Visit UF/IFAS Extension Sarasota County’s Sarasota Starter Kit: A Guide to Living on the Suncoast 30-minute webinars for new, or current residents.
Register for Neighborhood Best Practices an online, self-paced course that provides videos, fact sheets, resource links and more on topics from wildlife interactions to preservation areas, from water quality to sustainable landscapes to foster thriving, informed, and sustainable communities.
Other Series of Interest
“Wild Sarasota” blog series Enjoy blogs about identification, life history, and fun facts about our native wildlife. Accompanying webinars and resources on over 140 species of wildlife can be found at our Florida Wildlife webpage.
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