"A Wildlife Crisis of Unprecedented Proportions"

Little brown bats with white-nose syndrome.

Little brown bats with white-nose syndrome. Photo courtesy Nancy Heaslip, New York Department of Environmental Conservation

Managers at Great Smoky Mountains National Park have closed all of the park's caves to public entry until further notice. The move is in response to a growing concern about white-nose syndrome, a new malady that has already killed an estimated 400,000 bats in the Northeast, a situation the U. S. Fish and Wildlife Service (USFWS) recently called "a wildlife crisis of unprecedented proportions."

Today's announcement by the park is preventive in nature, but in light of a recent advisory by USFWS, it's a prudent step.

Bats probably don't score very high on the cuddly-creature index, and we seem to be bombarded with a steady stream of "the sky is falling" stories in the media, so this may be a situation which will leave many people wondering what all the fuss is about. It's worth paying attention.

In a scenario that sounds like the plot for a Hollywood sci-drama, the USFWS offers the following sobering information about white-nose syndrome (WNS):

Hundreds of thousands of hibernating bats have died since New York Department of Environmental Conservation biologists documented white-nose syndrome west of Albany, N.Y., in early 2007. Biologists with state and federal agencies and organizations across the country are trying to find the answer to this deadly mystery.

We have found sick, dying and dead bats in unprecedented numbers in and around caves and mines from Vermont to Virginia. In some hibernaculum[caves where bats hibernate], 90 to 100 percent of the bats are dying.

Bats which are afflicted display a white fungus growing around their muzzles, ears, and wings, giving rise to the name "white-nose syndrome.

One report on the problem offers a sobering assessment: "If WNS continues to spread at the current rate it has the potential to threaten entire species, including the already endangered Indiana and Virginia big-eared bats, and associated ecosystems."

The good news is that humans are not known to be susceptible to WNS, but the loss of viable bat populations would certainly have a direct affect on our activities, and on the ecological balance in many national parks. Bats play a major role in controlling insect populations—some bats can eat up to 2,000 mosquito-sized insect in a single night.

The Virginia Department of Game and Inland Fisheries notes:

The impact of white-nose syndrome on bat populations could be highly significant if the condition cannot be controlled and continues to spread. Some WNS caves in New York have experienced declines of more than 90% of the bat populations.

Losses in bat populations of this magnitude will cause a substantial ripple effect due to the important role that bats play as insect feeders and as a food source for other animals (hawks, owls, raccoons, skunks, and other animals that prey on bats)....

Connecticut Department of Environmental Protection Commissioner Gina McCarthy said,

While no one yet knows for sure what is causing WNS and why such large numbers of bats are dying, we will see the ramifications of this in just a few months. Far fewer bats will be out there working to consume mosquitoes and other flying insects that attack people as well as our forests and farmlands.

So, what can ordinary citizens do? If you're a caver—or know someone who is—you can help.

According to the Virginia Department of Game and Inland Fisheries, "How WNS is spread is under investigation, but it is suspected that transmission of the syndrome can occur by both bat and human traffic in caves. Many of the caves where WNS has been confirmed have been popular sites for recreational caving. Huge geographical leaps in WNS occurrences beyond the migration distances of bats, and in popular recreational caves, indicate that people who visit caves may inadvertently play a role."

Calling White-nose syndrome "a wildlife crisis of unprecedented proportions," the U. S. Fish and Wildlife Service (USFWS) issued a "cave advisory" last week.

The advisory asks that cavers curtail all caving activity in WNS-affected states and adjoining states to protect bats from the spread of WNS. (Those states are Pennsylvania, Connecticut, Massachusetts, New Hampshire, New Jersey, Vermont, and West Virginia; suspected cases in Virginia are awaiting lab confirmation.) According to USFWS,

"While the actual cause of WNS is unknown, scientists are reasonably certain that WNS is transmitted from bat-to-bat. However, WNS has been found in caves a significant distance from WNS-affected hibernacula, leading scientists to believe that something else is moving WNS."

"We suspect that white-nose syndrome may be transmitted by humans inadvertently carrying WNS from cave to cave where bats hibernate," said Northeast Regional Director Marvin Moriarty of the U.S. Fish and Wildlife Service.

The advisory asks that cavers beyond WNS-affected states and adjacent states use clothing and gear that has never been in affected and adjacent states. And finally, cavers everywhere should avoid caves and mines during the bat hibernation period (winter) to avoid disturbing bats. Specific suggestions for cavers in the advisory are important reading for anyone interested in that activity.

That brings us back to today's announcement at Great Smoky Mountains National Park. Bill Stiver, the park's Wildlife Biologist said, says that WNS "has not yet arrived in Tennessee or North Carolina, so we are closing all our caves to reduce the odds of the fungus hitching a ride to our protected caves on a caver coming from a state where it is already established.”

The closure at the Smokies applies to 17 caves and two mine complexes. A permit has always been required to enter those areas, so this action will not affect the average park visitor.

That's an important distinction, and the USFWS advisory does not affect public tours in developed sections of caves, where there's likely to be little or no contact with bats. I spoke this morning with Vicki Carson, Public Information Office at Mammoth Cave National Park. She confirmed that the usual visitor tours at Mammoth Cave are not affected.

To date, there have been no know occurrences of WNS in caves on National Park Service property, but the rapid spread of the problem raises valid concerns.

The NPS has assembled a working group to coordinate information and advise parks on their response to the problem, and so far, the approach has been for each park to establish its own local guidelines for recreational and scientific use of caves. Today's announcement at Great Smoky Mountains is an example of how that policy is being applied.

The race is on to find ways to slow and hopefully stop the spread of this problem. Actions such as the closure at the Smokies are currently the only defense available, and success or failure of control efforts may ultimately hinge on voluntary cooperation by cavers on private property and in remote locations on public lands.

You'll find lots more information about WNS on a U. S. Fish and Wildlife Service website, including a video.

Comments

This is very scary! I don't care if they are not cute and cuddly to most people. the fact that they are dying and scientists don't know exactly what it is or how we can stop it is not a comforting thought !I pray that they find out soon and save them!

I wonder if the fungus killing the bats is r/t the one killing frogs? We must remember this IS an evolving world.

Start a study on the effects of our doppler radar systems!

Could be super sonic frequencies that we are starting to create! This might block sonar for them to feed!

I didn't want to go into too much detail in the original article, but the mechanism of the fungus seems to be that it irritates the bats' skin during hibernation. As a result, the bats become active when they should be "sleeping," and burn up food reserves needed to carry them until food (i.e. insects) is available again in the spring. Some scientists believe the actual cause of death is malnutrition and/or dehydration resulting from this abnormal activity.

Get out your wallet! I have never seen a doppler of the inside of a cave. Boy oh boy.

It goes beyond "irritating" the skin, I have read that necropsies of affected bats show that the fungus has invaded the subcutaneous tissue!

I have to disagree with the not "cute and cuddly", many bats have very cute little faces, and their fur is softer than most cats and dogs... They are just too tiny to cuddle!

The WNS fungus (Geomyces sp.) is different than the Chytrid fungus (Batrachochytrium dendrobatidis, Bd) that is affecting amphibians.

I applaud GRSM for taking such a proactive approach in protecting the bat populations in the park, and I hope other national parks and sites will do the same.

annfro -

Thanks for the excellent additional information!

Re: whether bats are "cute and cuddly," I'll plead guilty to making a guess about the attitudes of the general population, most of whom probably have limited experience with bats. They are fascinating animals, and I hope more people will learn to appreciate them.

My Laymen's logic has me wondering if it is a coincidence that creatures whose food source is insects are now dying off from fungal diseases.
I have to wonder what insecticides and other pesticides may have done to alter the immune systems of bats and amphibians.
I Also wonder if it is merely a coincidence that white Nose Syndrome came on the scene at the same time as West Nile Virus.