A couple of days ago we posted an Aside looking briefly at a call from the Center for Biological Diversity‘ (CBD) for legislators to divert money to finding ways to stop the spread of a disease called White-nose Syndrome which is affecting hundreds of thousands of bats: Sign to save bats from white nose syndrome.

The facts are shocking, and though we don’t ordinarily write full-length posts on non-avian issues this is so serious - and the action that needs to be taken so urgent - that we’re going for it anyway…

White-nose Syndrome was first documented near Albany, New York in the winter of 2006–07, and in the winter of 2007 some 8,000 to 11,000 bats died at several locations in New York, the largest die-off of bats due to disease documented in North America. In the last two years the syndrome has spread rapidly throughout the state, and onto neighboring Vermont, Massachusetts, and Connecticut. This winter (2009) the disease has been discovered in five new states: New Jersey, Pennsylvania, New Hampshire, West Virginia, and Virginia. So far around a MILLION bats have died, and unknown numbers more are at risk.

Like something out of a particularly unpleasant horror movie, the most obvious symptom involved in the die-off is the growth of a white fungus encircling the noses of some, but not all, of the bats. The fungus is also found on the wings and tail, and in the spring/summer of 2008 USGS microbiologist David Blehert isolated it and identified it as a hitherto undescribed member of the group Geomyces, a genus of filamentous fungus in the family Myxotrichaceae that live in soil, water and air and are capable of growing and reproducing at refrigerator-level temperatures.

Although the new fungus is a close genetic relative of known Geomyces, it does not look like a typical member of this group under the microscope. Worryingly though it seems to be relishing conditions found in the hibernacula (hibernation caves) of North America’s bats, and Dr Blehert discovered that the fungus had colonized the skin of 90 percent of the bats his team analyzed from all the States affected by White-nose Syndrome.

Bats exhibiting White-nose Syndrome in a New York cave.
Photo © US Fish and Wildlife Service

If current trends continue the disease could soon hit some of the most significant bat caves in North America, which are located in the South and Midwest. Among the bat species at risk are the federally listed Indiana bat and Virginia big-eared bat. Winter surveys this year indicate Indiana bats have declined significantly in New York, where the species had been staging a recovery. Virginia big-eared bats are especially vulnerable to an epidemic like White-nose Syndrome; their entire global population winters in only a few caves in West Virginia and nearby States.

Does it matter though if North America loses its bats? Aside from the philosophical implications of us humans even questioning whether ‘it matters’ if millions of animals die off, bats play a vital role in healthy, balanced ecosystems. They consume enormous quantities of insects, including many that humans find problematic, such as mosquitoes and crop-eating moths and beetles.

Research has shown that where bats are present they significantly reduce damage to crops. Without bats, agricultural losses and costs to protect crops would rise. As the syndrome spreads, pushing vulnerable and even once common bat species to the brink of extinction (bats known to be affected, thus far, include ‘common’ species like little brown bats, northern long-eared bats, eastern pipistrelles, and small-footed bats, as well as the federally listed endangered Indiana bat), wildlife and land management will become increasingly challenging and expensive.

This needs to be stressed: if bats decline hugely (as they are doing right now), insects will increase. Pesticides (for example those used to combat West Nile Virus by killing huge number of mosquitoes which bats feed on) and other environmental toxins are already suspected as a cause of bat population declines generally, and the increased use of pesticides to offset losses of bats that will undoubtedly follow would lead to a disastrous spiral effect with escalating harm to both wildlife and people. We could end up soaking the countryside in pesticides, push stressed bat populations over the edge - and poison ourselves while we’re doing it…

While government biologists have worked valiantly to determine the cause and scope of White-nose Syndrome, they have worked in the absence of committed funding and adequate resources to confront the crisis. There is still no dedicated position for White-nose Syndrome co-ordination, and the exact cause of death has not yet been determined. Whilst the fungus is believed to be strongly associated with the problem (and its most obvious external manifestation) it may perhaps not be the actual cause of death. Most of the dead bats are also emaciated, and some of them leave their hibernacula to seek food that they will not find in winter: it appears that the impacted bats deplete their fat reserves months before they would normally emerge from hibernation, and die as a result.

Bats dead from White-nose Syndrome on floor of cave in New York.
Photo © US Fish and Wildlife Service

Researchers aren’t even sure yet if White-nose Syndrome emerged because this newly identified fungus was introduced into caves or whether the fungus already existed in caves and began infecting bats after they were already weakened from some other cause. It is not even known whether the syndrome is an infectious disease, the result of a toxin in the environment, or due to some other cause. What seems clear, though, is that hundreds of thousands of bats in the Northeast are dead or soon will be, and without action, certain populations — and perhaps even certain bat species — may be extirpated from the region for many decades or forever.

So what has the Center for Biological Diversity been doing to get this problem solved?

• The Center wrote a letter to the U.S. Fish and Wildlife Service on January 29, 2008, when news of White-nose Syndrome was first getting out to the public. The letter asked the agency to close all caves and abandoned mines to recreational use where the four federally listed endangered bat species in the eastern United States are found. If White-nose Syndrome is a contagion transmittable from one cave to another by people, on clothing and equipment — a theory still being considered by scientists — then spread of this affliction could be devastating to bats already endangered.

• In February of 2008, the Center petitioned the Fish and Wildlife Service, the National Park Service, the Forest Service, the Secretary of the Army, the Corps of Engineers, the Tennessee Valley Authority, and the Federal Highway Administration to re-evaluate federal projects where any endangered bat in the East might be harmed in light of the threat of White-nose Syndrome. These federal agencies oversee highways, dams, and logging in bat habitat.

• In April 2008, as bats continued to die with no new protections on the horizon, the CBD filed a notice of intent to sue the agencies.

• In 2009, after the Center joined with allies to file a protest against a plan to auction off oil and gas leases in a portion of West Virginia’s Monongahela National Forest (just a few miles away from a major hibernating site for Virginia big-eared and Indiana bats) the Bureau withdrew the area from the lease sale.

To quote from the information Mollie sent to us:

“We’re working to ensure that the federal agencies who manage the habitat where these endangered bats live proceed with caution in light of this threat we know so little about.

We’re also making sure we inform Congress that the Fish and Wildlife Service needs a sufficient amount of funding to study the causes of this syndrome.”

The reason we posted the original Aside was to ask readers to think about signing a petition managed by the CBD, and we’d like to ask that if you didn’t sign the first time round you please at least have a look this time. Mollie informed us today that 23 congressional members sent a letter to Sec. Salazar yesterday urging action on White-nose Syndrome - if ever the time to take action was NOW then this is it:

If you would like to offer support to the CBD:

     Mollie Matteson
     Center for Biological Diversity
     PO Box 188
     Richmond, Vermont 05477
     802-434-2388
     mmatteson@biologicaldiversity.org

• Update: For more information also see a June 01 article by Jeff Gillies at greatlakesecho.org/2009/06/01/great-lakes-bats-threatened-by-mysterious-disease/.