At Home - Bill Bryson [136]
The case was widely reported and resulted in a kind of vengeful hysteria. Officials at the highest levels concluded that extermination was an urgent and necessary step. Bats became the most friendless creatures in America. Years of steady persecution followed, and bat populations in many places suffered shocking depredations. In one case, the largest bat colony in the world, at Eagle Creek, Arizona, experienced a population fall from thirty million to three thousand in a matter of years.
Merlin D. Tuttle, America’s leading bat authority and founder of Bat Conservation International, a charity for bats, related a case, reported in The New Yorker in 1988, in which public health officials in Texas told a farmer that if he didn’t kill the bats in a cave on his land, he and his family and their livestock would be at grave risk of contracting rabies. At their instructions, the farmer filled the cave with kerosene and lit it. The conflagration killed about a quarter of a million bats. When Tuttle interviewed the farmer later, he asked him how long his family had owned the property. About a century, the farmer replied. And in all that time, Tuttle went on, had they ever been troubled by rabies? No, the farmer responded.
“And when I explained to him the value of the bats and what he’d done, he actually broke down and cried,” Tuttle said. In fact, as Tuttle pointed out, “more people die of food poisoning at church picnics annually than have died in all history from contact with bats.”
Today bats are among the most endangered of all animals. About a quarter of bat species are on extinction watch lists—that is an amazingly and indeed appallingly high proportion for such a vital creature—and over forty species teeter on the very edge of extinction. Because bats are so reclusive and often so difficult to study, much about their population numbers remains uncertain. In Britain, for example, it is unknown whether there are seventeen surviving species of bats or sixteen. Authorities haven’t got enough evidence to decide whether the greater mouse-eared bat is extinct or just laying very low.
What is certain is that matters everywhere may be about to get much worse. In early 2006 a highly lethal new fungal disease, called white-nose syndrome (because it turns the hair around the victims’ noses white), was discovered among hibernating bats in a cave in New York. The disease kills up to 95 percent of the bats that it infects. It has now spread to half a dozen other states and will almost certainly spread farther. As of late 2009, scientists still had no idea what it is about the fungus that kills its host, how it spreads, where it originated, or how to stop it. All that is certain is that the fungus is specially adapted to survive in cold conditions—not good news for the bats of much of North America, Europe, and Asia.
III
The direction of movement for populations is not always downward, it must be said. Sometimes populations boom, occasionally in ways that shape history. Never has that been more true than in 1873, when farmers in the western United States and across the plains of Canada experienced a devastating visitation unlike anything anyone had ever seen before. From out of nowhere there came swarms of Rocky Mountain locusts—great chirring masses of motion and appetite that blotted out the sun and devoured everything in their path. Wherever