What's Causing Bats to Drop Like Flies?
Researchers look beyond white-nose syndrome as the prime suspect in the mysterious deaths of bats in the U.S. Northeast
The mortality rate of the bats is guestimated at 97%. Researchers are linking two of the three main reasons for their deaths to pesticides and insecticides but have no conclusive evidence as of yet. It just breaks my heart. I hope they're able to figure out what's causing the problem and help to correct it before it's too late...
"Kunz and his team are approaching the mystery from three different angles: The first is to study the body weights of hibernating bats in different geographic areas by collecting samples of the creatures from three caves in the affected areas and from three caves in Ohio and Pennsylvania, where white-nose syndrome does not appear to have struck. Similar to Blehert's approach, this will inform Kunz and his team of whether the bats in the areas hit by the syndrome are beginning hibernation with the right amount of stored fat. If not, this might signal that pesticides are diminishing local insect populations, possibly choking off a primary food source for the bats.
The second angle is to determine whether the animals are storing the right type of fat (unsaturated fatty acids obtained by eating insects) for their dormancy, Kunz says. A lack of unsaturated fatty acids could again lead the scientists back to suspect declining local insect populations from insecticide use.
A third area to investigate is whether the bats' immune systems are being suppressed for some reason, making them more susceptible to fungal infection. "There's no smoking gun at this point," Kunz says, but he and his colleagues are collecting bat samples at this time and hope to have some results by December.
One possible bright spot is that some of the lesions on dead bats that Blehert and his colleagues examined had begun to heal before the bats died, which indicates that the bats are capable of fighting the infection to some extent. The researchers plan to spend this winter studying the effect of this fungus on healthy bats in the lab. Blehert says he will be surprised if the fungus alone was the sole culprit behind the plummeting bat population. "I'm not sure a fungus," he says, "can kill an otherwise healthy animal."