Sometimes We're A Little Batty

We discuss the benefits of the world's only flying mammal- the BAT!

Click here to learn more about which bats visit Georgia and how you can help volunteer with GA Anabat project to listen to your neighborhood's bats!

Click here for a list of nightblooming flowers to plant for bats and more about Bat Conservation International.

Click here to get your SAVE THE SKY PUPPIES sticker or to purchase a bat house that supports the GA Bat Working Group! Also visit the main page of Habitat for Bats to learn where to place your bat house by clicking here.

Transcript

 Corinne: Hi and thanks for joining Sapelo NERRds, a Coastal Science podcast. I’m your host Corinne.

Brittany: And I’m your host Brittany. We work at the National Estuarine Research Reserve or NERR on Sapelo Island, a Georgia barrier island.

Corinne: Some of our listeners may think that October would be a better time to talk about our favorite flying mammals, but I think you’ve given us good reason to bring them up in June.

Brittany: Oh yeah, the sky puppies! Summer is actually a great time to talk about bats! 

Corinne: I’m certainly seeing bats outside of my house at night nowadays.

Brittany: In the Northern hemisphere, bats are actually most active from May to early November. In coastal Georgia the warm temperatures and abundant insects keep bats pretty active during our evenings. But they shouldn’t scare anyone hoping to avoid meeting Dracula, all of Georgia’s species are insectivores: they only eat insects. So no vampires here!

Corinne: You’ve probably heard that one little brown bat can eat 1,000 mosquitoes in a single night. That sounds like a lot of bugs in the belly! You think that would stuff them like us after Thanksgiving dinner, but bats are amazingly athletic, even when they’re pregnant. Bats mate during the spring and summer and when females are pregnant they can eat over their body weight in bugs and still fly all the way home.

Brittany: Georgia has 16 species of bats, but on the coast there are usually about 9 to 10 species that you can see. These species include southern myotis, evening bat, eastern red bat, seminole bat, hoary bat, and the big and the little brown bats. 

Corinne: Many bats are coastal migrants in the summer months since, as you know if you’ve visited or live on the GA coast, we have tons of insects for bats to eat. So they have tons of food and few predators. However, many bat species are at risk and their numbers are declining. Of the 16 species of bats in Georgia, 9 are listed as species of concern on the 2015 State Wildlife Action Plan.

Brittany: Some of this decline is due to habitat loss. Many people expect bats to live in caves and a lot of species do, but many also live in tree cavities or nest in the Spanish moss. As trees are cleared for development or dead trees are removed from land, bats are losing their homes. And as you might remember from our episode Ice Ice Brumation that focused on what animals do in winter months, many bat species are facing huge losses due to white nose syndrome.

Corinne That’s right the Pseudogymnoascus destructans fungus that’s waking bats up in the middle of their winter hibernation, destroying their energy reserves and basically causing them to starve. At some known roosting sites 90 to 100% of the bats have died due to white nose syndrome. As of now, white nose syndrome hasn’t made it to coastal GA. That’s mostly because we don’t get or stay cold enough for bats to hibernate extensively. Plus the warmer days we get sprinkled through our winter months are warm enough that insects are out so that’s food for any active bats.

Brittany: Some people may not be concerned with white nose syndrome because it doesn’t directly impact people, but the harm to bats can have a big impact on us. Bats provide vital pest control and increase nutrients in delicate cave habitats. According to Ed Arnet, the Director of Programs at Bat conservation international, bats occupy a niche birds can’t fill at night - that’s a tremendous benefit to farmers worldwide. Losing the natural pest control services bats provide to just the agricultural industry in North America would cost anywhere between $3.7 billion to $53 billion dollars a year! 

Corinne: To monitor the bat populations in Georgia, particularly on the barrier islands, DNR Biologist Trina Morris conducts mist net surveys. Over the summer months Morris and her interns spend their nights searching for bats on 7 of Georgia’s barrier islands. In just one night on Cumberland Island they caught and released over 100 bats using a 20-foot tall net set up over a small watering hole. 

Brittany: Morris says “the bats come to tiny puddles on the island because freshwater is so limited.” This effort recorded 5 species of bats including the tricolored, big brown, and northern yellow which are high-priority species on the State Wildlife Action Plan, Georgia DNR’s document guiding efforts to conserve biodiversity across the state. These surveys are important to establish a baseline of bat populations before white nose fungus makes its way to the coast.

Corinne: Another way that scientists are working to establish baseline populations is with the Anabat system. This system is an acoustic detector that picks up the calls of the various bat species. As many people know, bats rely on echolocation for finding food and for navigation. As they make this call, Anabat records the ultrasonic calls of the individual bat species, making it ideal for species identification and activity monitoring. 

Brittany: Yep, I’ve actually helped with this project, driving around with an Anabat system on my car and listening to the high-pitched cheeps of the sky puppies feeding. Georgia DNR supports the GA Anabat Acoustic Survey Volunteer Project. Volunteers are needed for both the ongoing acoustic routes and for establishing new routes to monitor the bat populations in urban and rural areas of our coast. To check out data from previous year’s surveys or to volunteer for a route near you, follow the link in our show notes to the Georgia Anabat website. 

Corinne: Anabat actually came out to Sapelo to do a survey. Right near our office they recorded seminole bats, evening bats, hoary bats, and tricolored bats. On the other side of the island they found big browns and a lot more tricolored bats. 

Brittany: I know for a fact there’s a big brown and evening bat on Sapelo today.

Corinne: You mean the ones you brought with you in a plastic bin?

Brittany: Sure do! I’m assisting the Savannah Wildlife Rescue with rehabilitating two young bats for the next few weeks. 

Corinne: They look so adorable I just want to snuggle them, but there’s a reason I should let you handle them, right?

Brittany: That’s right. Hopefully most people know that bats can be a vector or transmitter for rabies. So do not touch or handle any bats that you find in the wild. While less than half of 1% of US bats have rabies, they are still considered a leading source of rabies transmission to other mammals - including humans. 

Corinne: You may think of animals with rabies showing odd behaviors like foaming at the mouth or biting at the air, it’s not as obvious in bats. They show paralysis rabies instead of aggressive rabies form. That’s why it’s important not to pick up any bats you might see on the ground unless you’re a professional. 

Brittany: I’m technically a bat professional - with a T not a D - although maybe sometimes bad professional would apply…Anyway, I have a PEP - a rabies pre-exposure prophylaxis or rabies vaccine. These series of shots allow me to handle and rehabiilitate rabies prone species like foxes, raccoons, skunks, and yep- Bats! Its really important to note that rabies only transports from saliva to blood so you cant get rabies just from touching these animals, they have to actually bite you. The problem with bats is that they have very very tiny mouths so sometimes their bites are unnoticeable. If you come in contact with a bat and are concerned it may have bitten you, its best to go get a Post-exposure vaccine. These vaccines are highly effective with greater than 99% survival after being exposed to rabies. There were no rabies deaths reported in 2019 or 2020 and just 5 in 2021, which was a pretty unusual occurrence. Most human transmissions of rabies actually occurs from domesticated animals like dogs and cats, but its always better to be safe than sorry with a disease that is almost certainly fatal if left untreated. 

Corinne: Thats why its important to call your local rehabilitator for baby bats, and now is the time of year that they might be found. Eventss like thunderstorms and tree clearings can cause babies to fall out of the nest during the day, when mama is not as likely to find them. 

Brittany: Habitat loss is a big problem for our coastal bats. That brings us to our listener question- “I heard you guys talk about Saving the Sky Puppies, which is pretty cute nickname for bats. I love bats and want to do more to save these awesome bug eaters! What are some more ways I can encourage them to come to my yard?”

Corinne: Thats an easy one! We’ve talked a little bit already about installing bat houses, but they are a great way to get bats in your area and reduce your need for pesticides. Bats look for the trifecta of habitats- Food, water, and shelter. While there are many attracting sprays on the market, they really dont work quite as well as providing a good source of protection, food and water.. We’ll include a link in our show notes on where to purchase bat houses for our area and what the best type of houses for your home are. Bat boxes need to be placed high enough above the ground on a sturdy tree or pole, about 16-20 ft off the ground. They prefer full sunlight exposure on the box during the day to keep them warm and toasty inside.  They can be places around homes to get rid of pests but also to prevent bats from going into your attic or crawl spaces in search of shelter. 

Brittany: Yep, using a bat house and an ultrasonic noise maker can drive the bats from your home and safely in to a bat house on the edge of your property quickly and humanely.

Corinne: The other two, food and water are easy as well, and are essential to encourage the bats to roost in your box! A small running fountain or pond is a great way to attract bats. They drink on the fly and will dip down and scoop up water, so they typically will not go to shallow bird baths since they might hit the bottom and prefer 7-10 ft of water length to drink successfully. A water trough works well as long as there is a small ramp to allow bats (and other animals) exit in case of falling in.

Brittany: And for food, well in Coastal Ga thats pretty easy! During dusk, we have plenty of annoying biting bugs for these guys to nibble. 

Corinne: Yea but you can help increase that by planting a Bat garden?

Brittany: Um, Corinne. They don't eat plants, we just established that.

Corinne: No, not for the bats to eat! Pollinator plants like purple coneflower, goldenrod, and night fragrant plants like Yucca or Sage help attract some variety of pest moths like the cabbage moth that bats then eat! These plants have the added benefit of also feeding day time pollinators like birds and bees, but don't worry- bats wont eat the bees since they only come out during the daytime to collect pollen. 

Brittany: That makes sense! Another way to help is also reducing your light pollution! Having community street lights on timers, turning off porch lights, and limiting inside light at night helps not only the bats, but also migrating birds! Previous studies suggested that street lights were beneficial to bats since they attracted bugs to a central location for them to eat. However, studies conducted by Bat Conservation International showed that most lights only benefit fast-flying species and most of the bats around our area are impacted negatively due to the timing of lighting. Bats use lighting cues to determine when to begin foraging at night and with excessive nighttime lighting in cities and most suburban areas, bats become disoriented and confused by light pollution and lighting during the night fragmented the network of established routes many bats utilize for feeding. 

Corinne: While you might think, the bats could just fly around the lights, the problem is these longer routes to avoid lights to get to foraging habitat can increase their energy demand and stress, making them more susceptible to diseases like WNS. 

Brittany: So Corinne you know that bats engage in a lot of activities at night, right?

Corinne: Sure, what’s your point?

Brittany: But did you know their most prominent activity is aerobatics….

Corinne: …Well you know why most softball games are played at night?

Brittany: Why?

Corinne: Because the bats have to sleep during the day!