Celebrating- and Saving- Michigan’s Most Misunderstood Mammals

October 23, 2024

By: Erin Parker, Interpretive Services Supervisor

Bats may be the most misunderstood mammal around. They have a reputation based mostly on myth, not fact, and because we rarely interact with bats in our daily lives, it’s hard to know what’s true or false about these fascinating creatures.

While it may be uncommon to encounter a bat, they’re one of the largest groups of mammals and make up more than one-quarter of all the mammal species on the planet. There are more than 1,400 species of bats in the world! Bats consume a wide variety of diets across the globe, including fish, insects, fruit, blood, and even nectar and pollen.

Bats of Michigan

Michigan is home to nine species of bats, and they are all insectivorous, meaning their entire diet is made up of insects, primarily those that fly like mosquitos and moths. Bats may be solitary, such as the big brown bat in the photo or more social, like little brown bats. Gregarious bats may group up in the hundreds of thousands in the winter months during their hibernation. Solitary bats typically roost in trees, either in among the leaves or under the bark. Social bats use the habitats we may think of when we think about bats: our attics or barns, caves, mines, tunnels, and other similar locations.

Myth-busting

Bats aren’t blind. Their small eyes may be hard to spot in their fluffy fur, but their vision is fine and they can and do depend on sight during daylight hours. Bats here in North America also have an incredible adaptation to their mostly nocturnal lifestyles: echolocation. This is the use of high-frequency soundwaves that the bat emits and that bounce off all kinds of objects, from potential prey to obstacles in the bat’s flight path, feeding important information back to the bat. This extra navigational sense helps bats thrive after dark when many other animals are asleep. Echolocation is unique, even among bats. The giant “flying foxes”, about 180 species of bats from parts of Asia, Australia, and Africa don’t typically echolocate. These bats are frugivores or fruit-eaters and may use sight and smell to locate their food.

Bats are also able to detect material as fine as a human hair, so they’re unlikely to get stuck in yours! Most likely, if a bat is swooping next to you, it is aiming for the insects attracted to your warm body and exhaled carbon dioxide.

Bats aren’t rodents (like mice and rats). They belong to their own family, the chiroptera (hand-wing). And they’re not dirty or pest-ridden. They spend time grooming themselves to keep their fur neat and some species even groom each other. Bats give birth to live young, called pups, and many species roost together in maternity colonies where the mothers and babies cluster in tightly packed groups to stay warm. Bat pups don’t fly right away, so they stay behind in these warm colonies while their mothers hunt for insects- each mother bat returns to her young and they may recognize them by scent, echolocation, and even their individual ‘voices’!

Bats do carry rabies, but it occurs in extremely low rates in wild populations. Any bat that is acting strangely should be left alone – by people and pets. Bats don’t have any higher levels of rabies in their wild populations than any other groups of animals.

Bats do drink blood…but only 3 species of “vampire” bats exist and they prey predominantly on chickens and other domesticated farm animals. And they take such small quantities of blood that they rarely cause much harm. Unlike the movies, vampire bats don’t actually suck blood. They make a small bite with their sharp teeth and lap up the blood. These bats are found in Central and South America, and occasionally in southern Texas.

Threats to bats

Habitat loss, a changing climate, declining insect populations, increased use of insecticides, people’s misunderstanding and fear…it seems like the threats to bats are endless! But one of the largest threats, at least in the United States, came in the form of a fungus that has decimated bat populations in the eastern and midwestern US.

White-nose syndrome, named for the powdery-looking white fungus on many infected bats’ faces, is caused by a fungus aptly named Pseudogymnoascus destructans probably came over from Europe on the shoes or gear of cave-exploring humans. While European bats have evolved along with the fungus, North American bats have not. The fungus thrives in the cool, damp caves, culverts, mine shafts, and other places that large groups of bats use for their winter hibernation period. And because these types of bats are social, it spreads readily. The first signs of white-nose in Michigan were observed in 2014. Now, 10 years later, several bat species’ populations have crashed- in some hibernacula (overwintering

sites), bat mortality from white-nose syndrome was 100%. Surveys conducted by Michigan Department of Natural Resources and others¹ determined that overall, bat populations of several species declined about 89% since white nose was first reported. The bats don’t die from the fungus itself, rather it seems to cause them to wake more frequently during their winter hibernation, causing them to use up energy stores during a time of year when their only food source (insects) is nonexistent.

Luckily, there is some good news². Several potential treatments are in the works and the bats that survived white-nose exposure, seem to have genetic traits that may help future generations of bats survive and thrive.

Celebrating bats

And, once you learn about all of the unique adaptations that bats have to survive, you may just find yourself enamored of bats…just in time for Bat Week! Bat Week, taking place October 24-31, 2024, is an opportunity for people all over the world to learn about and celebrate bats. Check out batweek.org for more information, educational materials, and events.

We can all help bats in our backyards, parks, and communities by:

• Reducing our use of pesticides in the insects that bats (and birds) consume
• Planting night-blooming flowers that attract pollinating insects – and that, in turn, feed bats
• Leaving snags and standing dead trees when they don’t pose a safety risk, these not only provide habitat for birds but also bats
• Reduce light pollution by turning off unnecessary lights at night, providing more darkness helps bats and other nocturnal hunters such as owls
• Share your love of bats with others and help people differentiate fact from fiction

 

References:

1.Bats & White-nose Syndrome Status in Michigan

2. A fungus decimated American bats, now scientists are fighting back (gifted article)

Resources:

Batcon.org

Batweek.org

Books about bats for kids:

Bat Count: A Citizen Science Story by Anna Forrester

Nightsong by Ari Berk

Little Red Bat by Carol Gerber

The Bat Book by Charlotte Milner

Amara and the bats by Emma Reynolds