I've always assumed that animals gradually become endangered over a long periods of time, like many decades. But I was totally wrong: a bat species that once swarmed caves in North America has lurched towards extinction in just six years.
A so-called "white nose" fungus has killed up to 6.7 million little brown bats since 2006 that until recently were one of the most common bat species in North America.
According to the Federal Fish and Wildlife Service, once the fungus gets into a cave or mine, it kills 70-90 per cent of the bats hibernating inside -- in some cases it has wiped out every last one. Ann Forschaur from the agency told the New York Times:
We knew numbers for endangered species like the Indiana bat. But we never made it a priority to count something like little brown bats, because, well, they were everywhere. It didn't seem possible that they would be in danger of extinction in just a couple years.
In 2009, the fungus was found at 88 sites in nine states; today scientists say it has infested at least 200 sites in 16 states. But it's spreading so fast that officials can't even keep up the count.
The critters look like they've indulged in too much nose candy, but the syndrome is caused by a fungus called Geomyces destructans, which grows at temperatures below 20C. Conservationists think it spreads on the bats themselves and possibly on human clothing. They also believe it's so damaging to American bats because it came from Europe, where bats have developed defences against it.
Twenty-six of the 45 North American bat species are potentially susceptible to the fungus. If that many species were wiped out it would be hugely damaging to ecological systems. Not only do bats help maintain a balance in the animal kingdom, but they also save farmers $US3.7 billion a year by munching on pests.
From everywhere to extinct in less than a decade? It's apparently possible, and really terrifying.