Significant effort has been put in over the years to conserve Michigan’s bats, and we would be remiss not to celebrate that work during Wildlife Conservation Month.

You might not think bats need our help, particularly if you see a lot of them around on warm summer nights; however, many bat species are in decline nearly everywhere they are found, including in Michigan.

White-nose syndrome is a major culprit in this decline. This deadly disease affects bats in Michigan and throughout North America. Infected bats prematurely awaken from hibernation, rapidly deplete their fat reserves and are unable to survive the winter. Bats with white-nose syndrome often exhibit unusual behavior, such as flying during daylight hours or gathering outside of caves in cold weather.

Several bats flying through a gate at a protected hibernacula site at night with a tree in the background.

The Michigan Department of Natural Resources has been working with several researchers on different methods to try and mitigate the impacts of white-nose syndrome and has made efforts to protect many hibernacula (where bats spend the winter) throughout the state.

One example, to minimize human disturbance to hibernating bats, is gating entrances to important bat hibernacula. Custom steel structures are designed and put in place to ensure public safety while allowing the bats to freely come and go from the hibernacula.

“Some of these gated sites are important locations to protect because they house large populations of bats in the winter,” said John DePue, wildlife biologist with the DNR.

A researcher holding a vile and dressed in a white protective suit, blue gloves and hard hat prepares to take a sample in a mine shaft.

Michigan is also one of only a few states that participates in field trials of potential treatments to combat white-nose syndrome.

Working with the DNR, researchers and students from Western Michigan and Ball State universities have been applying an organic compound—derived from shellfish, called chitosan—to bats and the inside of hibernacula. This chitosan compound appears to help bats combat the effects of white-nose syndrome.

Researchers from University of California, Santa Cruz have been treating some of Michigan’s hibernacula with chlorine dioxide. The treatment is applied to the site when bats are not present to reduce the number of spores that cause white-nose syndrome.

DePue said that chlorine dioxide is used to disinfect the site by killing the fungal spores during the summer, before bats return for the winter in order to reduce infection and mortality rates.

“We’ve also noticed, through annual hibernacula site monitoring over the years, that sites with cooler temperatures have lower mortality rates from white-nose syndrome,” said DePue. “This is likely because the growth of the fungus may be suppressed at these lower temperatures.”

In partnership with Michigan Tech University’s Geological and Mining Engineering staff and students, MTU forestry and wildlife students, as well as Bat Conservation International, efforts are underway to use mining ventilation techniques to reduce the temperature at the Carp Lake Mine hibernacula site by a few degrees to see if it will have an impact on bat survival rates.

In another partnership, DNR staff members have been working with a team of researchers from Virginia Tech to study bat microhabitat use. In other words, researchers are looking at smaller, more specific areas within a larger habitat, such as portion of a cave or mine, that the bats are using and noting which features of that microhabitat differ from the larger habitat around it. Information from this research will help inform future bat management decisions.

A researcher recording data during a bat hibernaculum survey at Tippy Dam.

Annual bat monitoring is also conducted by DNR staff and researchers from Eastern Michigan University. Hibernation sites are visited during the winter to learn about places where bats are experiencing higher survival rates, and to monitor population trends.

You too can give bats a helping hand by conserving bat habitat, putting up a bat house, complying with mine closures and following decontamination guidelines to reduce the spread of white-nose syndrome. Learn more at Michigan.gov/Bats.

Please remember, bats, like all wild animals, should be treated with respect and left alone. For your safety, if you find a bat outside, leave it alone. In situations where a bat has been in close contact with people, if possible, safely confine the bat and contact your local health department to determine if it should be tested for rabies. Learn more at Michigan.gov/Rabies.

In the past several days the Kent County Health Department (KCHD) has started to receive reports from people who have had contact with bats indoors. While these types of encounters are not uncommon in August, any direct contact with a bat represents a potential exposure to rabies.

It is critically important to capture the bat for testing if there is reason to believe a person may have been bitten or scratched by a bat. Do not release a bat if you find it in the room of a sleeping person, an unattended child, someone who is mentally impaired or an intoxicated individual as they may have been bitten without their knowledge.

A captured bat in Kent County will be sent to the Michigan Department of Health and Human Services for testing. If the bat tests negative for rabies, then no treatment is required. However, if a bat tests positive, or if the bat is not available for testing then the exposed person should receive the post-exposure prophylaxis for rabies.

To safely capture a bat, experts recommend that you wear leather gloves to avoid being bit. Place a box or a coffee can over the bat and then slide a piece of cardboard under the container to trap the bat inside. Secure it with a piece of tape and contact the Kent County Health Department at 616-632-7200 during regular business hours. If you know that you have been bitten or scratched by the bat and the exposure has occurred outside of normal business hours, seek medical attention but keep the bat.

While relatively rare in the United States, human cases of rabies are almost always associated with bats.

Rabies is a viral disease that affects the central nervous system and is invariably fatal once symptoms appear.

“Bat encounters rise every year during late August and early September,” says Adam London, Administrative Health Officer at KCHD. “We can’t stress enough how important it is to be able to perform tests on these animals. Unless you are certain that no one has been bitten by a bat you find in your home, please do not let it go.”

The Michigan Department of Agriculture and Rural Development (MDARD) State Veterinarian Dr. James Averill urges Michiganders to adopt practices that help protect their families, pets, and livestock from rabies, one of the deadliest diseases known to man. According to the World Health Organization, rabies is responsible for the deaths of 55,000 people worldwide.
All mammals are susceptible to rabies.  Rabies virus is usually transmitted via the bite of an infected animal. The virus can also be transmitted in the saliva of an infected animal into an open wound or onto mucous membranes such as the eyes, nose, or mouth.

“Michigan has rabies laws and programs that help protect citizens. Animal bites are reportable, and the State of Michigan requires dogs and ferrets be vaccinated against rabies,” said Averill.
Protect dogs, cats, ferrets, horses, and select livestock by keeping them vaccinated against rabies. If a person suspects their pet or livestock may have had contact with a potentially rabid animal, they should immediately contact their local animal control agency and veterinarian.
“You cannot always know if an animal has rabies, but if your pet or livestock behave aggressively and this is not normal behavior, you should consider rabies as a possible cause, and take appropriate precautions,” Averill said. “If a person is bitten by an animal, they should immediately wash the wound, seek medical attention, and report the bite to the local health department.”

Signs of rabies in animals can include lethargy, depression, aggression, seizures, a change in behavior, difficulty swallowing, excessive salivation, difficulty walking, and eventual death. Because many illnesses can cause these signs, without the laboratory tests rabies cannot be diagnosed.  It is not possible to test live animals for rabies. In order to determine if an animal has the disease, a necropsy must be done and the brain tissue must be examined for the presence of characteristic lesions.
To date, for 2013, there have been 39 cases of rabid Michigan bats in the various counties. See map for statistics.
For more information, please visit: http://www.michigan.gov/documents/emergingdiseases/Rabies_Map_2013_407912_7.pdf