Protected Species in Pennsylvania: The Indiana Bat

The Indiana bat is a small mammal that's typically less than 2 inches in length, weighs only ¼ of an ounce and has a wingspan of 9 to 11 inches. The fur of the bat ranges from black or dark gray to a dark brown. It is often mistaken for the little brown bat (Myotis lucifugus) due to its similar size and coloration. The Indiana bat is a very social animal and can be found hibernating in limestone caves in large clusters. The species occur along much of the east coast and into the Midwest, ranging from Vermont to northern Florida and west as far as Oklahoma. In the summer the bats migrate into wooded areas, where they often roost under the bark of trees or in cavities in dead trees. They also can be found roosting in manmade structures, such as attics and barns. Bats that are found roosting in these areas might be a group of pregnant females referred to as maternity colonies. This is a critical time for the Indiana bat. Females typically only have a single pup in June or July and if they're disturbed while in these roosts, this could lead to the loss of the pup. Learn more about the life of bats in this Extension article.

Why are they listed?

The Indiana bat is currently listed as "endangered" under the Endangered Species Act, which means that the species are at risk of extinction unless actions are taken to help the species recover. Declines in this species are due to multiple factors including habitat loss, environmental contaminants, human activities and disease. The most crippling of these factors is a fungus known as white-nose syndrome (WNS).

Figure 1: Bat infected with white-nose syndrome. Photo credit: USFWS

This syndrome is a fungus that affects many types of cave hibernating bats. It gets its name from the white fungus that can be found on a bat's nose when it's infected. It was first found in North America in 2007 in caves near Albany, New York. The fungus can attach to people's clothes, shoes, or equipment and can be transported by humans exploring caves. The infection can cause strange behaviors in bats such as flying outside during the day and during winter hibernation. This behavior causes them to use up their stored resources needed to survive through the winter.

Since 2007, the fungus has had a very detrimental effect on bats, killing millions, and the disease has spread to many locations where bats hibernate (i.e., hibernacula). While there is no cure for WNS, but there is a large push to create a vaccine. In the meanwhile, measures have been taken to reduce the spread of WNS. Foremost has been educating the public and forbidding humans to enter certain caves which may lead to spreading the disease. In addition to preventing harm, people can also help bats by providing bats with a disease-free place to hibernate. Specific recommendations on how to help the Indiana bat can be found at the end of this article.

Why should I care about bats?

Similar to other bats, the Indiana bat plays an important role in helping maintain the health of natural areas by keeping ecosystems in balance. Bats are the primary predators of night-flying insects, including a large number of moths, mosquitos, and other pests. By keeping insect populations low farmers can reduce their need for pesticides which also helps the environment and the economy. For example, it is estimated that insect eating bats can save farmers up to $53 billion dollars every year by controlling pests. Similarly, other types of bats in other regions serve as pollinators of wild and domestic crops. There are over 500 plant species that rely on bats to pollinate their flowers. Unlike bugs who prefer more brightly colored daytime flowers, bats prefer pale lightly colored flowers normally bell-shaped. Without bats, much of the flowering plants and produce we enjoy would not be available. 

What can I do to help?

Avoiding Contact

Many bats that live in regions with cold winters must hibernate to stay alive. If a bat is disturbed during hibernation it may awake and become active. This increased activity can lead to starvation because of a lack of food before winter is over. The introduction of White-Nose Syndrome is primarily caused by the disturbance of the caves that bats rely on for hibernation. Avoiding these areas can help prevent disturbance of bats and the spread of disease between the bats. Consider the following:

1. Stay out of caves during bat hibernation cycles.
2. When in caves, keep from touching walls and ceilings to prevent the spread of harmful bacteria.
3. Wash and sanitize yourself and your gear before entering and after exiting a cave to prevent the spread of White Nose Syndrome.

Habitat Aid

The Indiana Bat requires two separate types of habitat; caves for hibernating and trees for roosting. One way to help the bat population is by providing or protecting roosting habitat. This can be done in a few ways:

1. Keep in mind which trees have large crevice's and peeling bark that may be good for roosting and avoid cutting them down.
2. Plant additional trees that may be used for roosting. Go to "Characteristics of Indiana Bat Summer Habitat" to learn which trees make the best roosting trees.

Student Authors:
This article was written in coordination with undergraduate students Kaleb Lange, Brantly Ensor, Jessica Clark, and Zach Garner as part of a class project in the Department of Ecosystem Science and Management at Penn State. You are invited to leave comments for the authors at this link.

References

U.S. Fish and Wildlife Service.

Kentucky Bat Working Group. 

Butchkoski, E. (2010, February 10). Indiana Bat. 

WNS Response Team. What Is White-nose Syndrome?