Our flying mammal cousins are a traditional spooky accessory to Halloween celebrations, but California's wildlife agency wants us to remember that bats have far more to fear from us than we do from them.
Still feared by many people after centuries of scary myths, California's 25 native species of bats are actually quite shy, preferring to avoid contact with humans. Bats are important pollinators of many wild plants, including agaves and saguaros. And each bat can eat 600 mosquitoes or other insects per hour of feeding: a huge benefit to our quality of life.
That's a far cry from drinking blood -- which only 3 of the world's 900-odd bat species do, none of them residents of California. And bats don't harbor unnerving desires to get entangled in your hair, either. Such anti-bat myths are tenacious, but people can often let go of them when they learn just a little bit about the intriguing creatures.
"Because bats are nocturnal, fly and have teeth, many people fear them. What the public doesn't realize is that bat populations play a huge role in controlling insects," said Scott Osborn, an environmental scientists working with the California Department of Fish and Wildlife. "Bats have amazing abilities -- they are the only mammals capable of true flight. Their unique ultrasonic sonar system enables them to navigate and to catch insects in flight in complete darkness. Once people get to know bats, fear gives way to admiration."
And California's bats can use all the admiration they can get. Practices ranging from felling old-growth forests to spraying insecticides to developing desert habitat have seriously hurt populations of many bat species, depriving them of habitat and food. Increasing wind turbine development has nearly eradicated bat populations in some areas.
What's more, an even more ominous threat looms to the east: white nose syndrome, the fungal infection that has been devastating bat populations in the eastern U.S. and Canada. The infection interferes with bat hibernation, and infected bats apparently starve to death from using energy when food isn't available. No cases of white nose syndrome have yet been reported in California, but at least three of the state's species are known to be extremely susceptible to the infection. White nose syndrome has killed millions of bats in North America, with mortality rates approaching 100 percent in some colonies.
No one knows just how white nose syndrome got to North America. It's been infecting resistant bats in Europe for a very long time, though, and one possibility is that spelunkers, a.k.a. cavers, brought the spores of the fungal disease to North America on their clothing or gear.
Fortunately, cavers are an environmentally sensitive lot for the most part, and most people in the cave exploration community are happily abiding by the decontamination protocol suggested by the U.S. Fish and Wildlife Service, which involves submerging potentially contaminated gear and clothing in antifungal products. (Simply washing clothing doesn't work.) You can help even if you're not a caver by respecting cave and mine tunnel closures. (Actually, you should do that last thing even if there aren't any bats around.)
It remains to be seen if and when white nose disease will make it to California. In the meantime, this week's holiday offers a good excuse to remind us all that it's good to have bats around for insect control, for pollinating desert plants, and just because they're fascinating. Wave the next time you see one. You may not get to for a whole lot longer.