Tuesday, October 26, 2010

A Trick, No Treat For Bats: white-nose syndrome hits hard

Halloween's approaching and for those who celebrate "All Hallowed Eve" there's candy, costumes, and images of all things spooky - like zombies, witches, and bats. What would the world be like without those things that go bump in the night? Well, we could do without the zombies, I think. And perhaps witches, both the green Wizard of Oz kind and the ones running for political office.

Then there's bats. What would the world be without bats? As it turns out, it would be a world nearly overrun with bugs. Bats are one of the planet's great equalizers, feeding on insects and helping to keep the populations in balance. While not exactly an "apex predator" like sharks, bats serve a very similar role. Sharks and other large predators that reside at the top of the predator-prey pyramid are kept in check by a slow reproductive rate. Not so for the bat, but then it's feeding on insects that can number in the millions.

So, bats, those spooky little critters of Dracula movie fame that can congregate in caves by the thousands and make us run for cover lest we get one in our hair, are actually very important to maintaining a healthy ecosystem.

But in the eastern United States, parts of Canada, and even France, we are losing vast numbers of bats to a disease: white-nose syndrome. This syndrome manifests itself as patches of white fungus on the nose and wings of the bat. There are several suspected fungi thought to be possibly involved, although Geomyces destructans is considered the most likely culprit. It is a cold-temperature fungus that can flourish in the caves that bats inhabit. The white-nose syndrome disrupts the bats normal winter hibernation cycle and produces behaviors, like flying, that can lead to the bat's death, often from starvation (due to a combination of excessive activity combined with the winter's lack of food).

No more ugly little bats. Big deal, right? So what if there's a few more insects, right? We'll just use a rolled up newspaper or get out the bug zapper. Oh, were it that simple.

Actually, the loss of bats in the northeast all the way to the Mississippi poses a tremendous economic threat to agriculture, as bats act as a very important insecticide control agent. Without bats, insects would ravage more crops, more pesticides would have to be used (with their own inherent problems), and food prices would soar. The timber industry would also be effected.

Scientists who have been studying the condition are not exactly sure as to how it is transmitted over such a wide area. To rule out any human involvement, the U.S. Fish and Wildlife Service has strictly limited access to known caves where large number of bats live. But the condition appears to be continuing to spread, having first been reported in 2006 and now affecting 9 different bat species. Research has found that the fungus reacts to some human anti-fungal treatments but how those can be applied practically has yet to be determined.

The Center for Biological Diversity (CBD) is running a campaign to get the attention of U.S. Secretary of the Interior Ken Salazar to devote serious effort to the issue. Whatever initiatives and small cost that might be required (CBD suggested $10 million), that would easily be offset by the multi-million dollar savings to agriculture and the consumer.

Trick or treat. Looks like it's a trick for the bat this year.

Support the Center for Biological Diversity's petition campaign to save U.S. bats.


Anonymous said...

White Nose Syndrome has not been observed in France. The fungus characteristic of WNS, G. destructans, has been discovered on bats in France and other parts of Europe, but the massive bat deaths of WNS have not occured in Europe.

RTSea said...

You are right that the widespread death of bats that has occurred in the northeast U.S. and Canada has not yet been seen in France.

According to the CDC, as you mentioned, the same fungus associated with the U.S./Canadian deaths was discovered in 2008, but has not manifested itself into a fatal pandemic as of yet. While the finding illustrates the international range of the fungus, let's hope that France will continue to escape the tragic results. Thanks for the clarification.

Source: Puechmaille, Sébastien J.; Verdeyroux, Pascal; Fuller, Hubert; Ar Gouilh, Meriadeg; Bekaert, Michaël; Teeling, Emma C. (February 2010). "White-nose syndrome fungus (Geomyces destructans) in bat, France" (PDF). Emerging Infectious Diseases (Atlanta: Centers for Disease Control and Prevention)