MN Bat Removal | Bat Exclusion
Bats are undoubtedly one of the most under-appreciated mammals in the animal kingdom. Believe it or not, while some people fear them, others just love these unusual and often misunderstood creatures of the night. The fact that bats only come out at night and their ability to hide in tight, secret places probably only add to humans’ bat fear and superstition. But in fact, bloodsucking vampire bats, the stars of many Dracula films, don’t even live in the United States or Canada, although they can be found in South America and there are a few in Central America. The bats in our neighborhoods are insectivores, which of course means they live on insects. They consume a tremendous number of mosquitoes and other insects every night. A single little brown bat can alone catch up to 1,200 insects in just one hour.
Even though they’ve been given a bad rap, bats really do more help than harm. Bats are saving us big bucks, to the tune of at least $3 billion a year in pest control by patrolling the skies at night above our fields and forests gobbling up insects that eat or damage our crops. Without bats, the insect population would run rampant which could deal a huge blow to Minnesota’s agricultural economy.
Deadly Bat Disease In Minnesota
Whether you love them or not, we need our bats. Especially now. Unfortunately, the tiny creatures are now being threatened by a disease that strikes during the winter. The Minnesota DNR has been confirmed a fungus dangerous to bats at Soudan Underground Mine State Park and Forestville/Mystery Cave State Park, according to the Minnesota Department of Natural Resources (DNR).
The fungus is known to cause white-nose syndrome (WNS), a disease that is harmful and mostly fatal to hibernating bats, and has decimated bat populations in the eastern portions of the United States and Canada.
While only a few bats have tested positive for the fungus, the discovery has serious implications. If Minnesota follows trends of other states, the disease is likely to be present in Minnesota bats within two to three years.
“This is bad news for an important mammal in our ecosystem,” said Steve Hirsch, director of the DNR’s Ecological and Water Resources Division, which oversees the agency’s nongame wildlife program. “We’re prepared with special protocols to help keep the fungus from spreading.”
Public tours of Soudan Underground Mine and Mystery Cave will continue, but visitors will begin each tour with a brief lesson on how they can prevent the spread of the fungus.
After tours, visitors will be required to walk across special mats designed to remove spores from footwear. They will be advised not to visit other caves or mines with any clothing, footwear or gear they have used in areas where WNS or the associated fungus is present because washing alone cannot sufficiently disinfect clothing.
Ed Quinn, natural resource coordinator for the DNR’s Parks and Trails Division, said, “Education is one of the most effective tools we have to slow the spread of the disease.”
DNR nongame biologists and park managers have been working for several years with the U.S. Fish and Wildlife Service and leading bat researchers to learn more about and prepare for the disease.
The DNR’s actions are consistent with the National White-Nose Syndrome Decontamination Protocol, part of a nationwide effort to slow the spread of the disease. The DNR urges owners of private caves to learn about WNS and take similar visitor precautions as outlined in the protocols.
Sampling for the fungus at the two parks occurred in 2012 and 2013. Recent testing to track the spread of the disease found that four bats of 47 sampled were positive for the fungus. Testing was part of a national study funded by the National Science Foundation and led by researchers at University of California Santa Cruz and Northern Arizona University.
Minnesota has seven species of bats, four of which hibernate during the winter and are at greatest risk of contracting the disease. Mystery Cave, located in southeastern Minnesota, has about 2,300 bats. Soudan Underground Mine, in the northeastern part of the state, has 10,000 to 15,000 bats.
Gerda Nordquist, a DNR mammalogist, said the DNR will continue to monitor Minnesota’s bat populations closely, because healthy bat populations are important both ecologically and economically.
Many species of bats feed voraciously on insects, resulting in billion of dollars in savings to Minnesota farmers each year by providing pest control, according to a 2011 article in Science. When the farmers lose more crops to it and they have to apply more pesticides. Those things are expensive.
WNS is named for the fuzzy white growth of fungus observed on infected bats. In bats infected with the WNS fungus, unusual behavior often will be observed, such as flying during the day in the winter or roosting outside when temperatures are below freezing.
The DNR asks people to help monitor bats statewide.
“If you see anything unusual — sick or dead bats or bats acting strangely — at Minnesota state parks or elsewhere, please report it as soon as possible,” Nordquist said.
Reports can be submitted online, using the bat observation report on the DNR website. These reports will be reviewed by DNR staff, and additional follow-up or testing will be conducted, as needed.
Visit these sites to learn more about white-nose syndrome:
- Minnesota Conservation Volunteer article, “A Coming Crisis for Our Bats.”
- www.whitenosesyndrome.org (includes a map showing the spread of WNS and a downloadable brochure about the WNS tragedy, “Battle for Bats”).
Bats actually prefer to avoid human contact; It’s just a gentle little creature that wants to do nothing more than eat bugs and sleep all winter. Still, it can be quite unnerving to have them in your home. Most people do not tolerate that idea very well, and it becomes necessary to evict the bats and make repairs as needed to prevent them from entering in the future. Accumulations of their droppings (guano) can cause odor and bug problems, which is the primary reason bats should be excluded from a structure occupied by people.
Bat removal is an intricate and difficult task that Wild Animal Management Experts deal with on a regular basis. Even if you successfully found a way to trap a bat colony and drove them to a place far away, bats have been known to fly back to their home site up to 500 miles away in a few short days or weeks.
Until exclusion can be performed, the problem of bats entering the living quarters can be solved or minimized by sealing all holes and cracks leading from the attic into your living areas. Holes along TV cables, water pipes, and cracks in drywall or gaps in ceiling tiles are all possible entrance points. Gaps under doors leading to attics and closets are common entry points. Remember, it is illegal to kill bats, as most are state protected and some federally protected. It is also illegal to use any type of poisons or chemicals for bats.
Bat exclusion measures should only be done between Sept 1 and March 1, as there may be young bats in the colony that are still unable to fly. The young bats would die without their mothers, and an attic full of dead animals is much worse than having the bats roosting there.
Bat removal requires special bat-trapping techniques. This way, the bats will be treated in a humane manner and allowed to live, just not in your attic. There are many old wives’ tales touted as remedies for bat removal. They DO NOT work. There is no registered or effective bat repellent available. Some companies will try to sell anything. There are lot of so-called bat-repellent or bat-away products on the market, but they are bogus. And those high-pitch noisemakers? The FTC has issued a warning against them – ultrasonic sound emitters do not work. There is no quick and easy fix when it comes to bat control. It’s best to have a professional bat removal expert with years of experience evict the bat colony and then bat-proof the entry points so they can’t squeeze in again.