What is the White Nose Syndrome in Bats?

White nose syndrome is a name given to a serious disease and a fungus that appears to be affecting and killing many types of bats in the Northeastern part of the United States. The name white nose syndrome refers to rings of white found around the noses of many dead bats, but in those instances where the fungus is found on bats, it’s been tested and shown to be of several origins. Most fungi involved are on the bats’ bodies, and not found internally.

The numbers of bat deaths due to the mysterious white nose syndrome are astronomical, and threaten to add several types of bats to the endangered species list. In particular, the Indiana bat, which already made that list, is seen as at special risk, though other species, particularly the Little Brown Bat, have suffered greater population decline. White nose syndrome does appear to spread from one species of bat to another, especially when different species of bats winter together in a cave in what is called a hibernaculum.

What has scientists puzzled is that not all bats that have died have white nose syndrome. Yet all appear as though they have not been eating or drinking. Scientists don’t yet know whether the fungi affecting the bats causes them to behave abnormally, or is a symptom of the bats not behaving normally. The syndrome is of such great concern that the United States Fish and Wildlife Service has asked people coming in contact with bats, such as cavers or spelunkers to report, but be sure not to touch, any bats they observe with the syndrome, or any dead bats.

Scientists are also unclear if white nose syndrome poses a threat to humans. They recommend never picking up a dead or sick bat (good advice in any case due to most bats’ ability to carry rabies). The US Fish and Wildlife Service also suggests that any clothing that comes into contact with bats be removed and washed, and that those who visit caves wear protective gloves, hats and clothing to avoid physical contact with bats even if the bats appear well. Dead bats should be reported to the Fish and Wildlife Service.

Thus far, the areas where the syndrome has been most prevalent include New York, Vermont, Connecticut, and Massachusetts. In areas where it has been found most, some bat populations in specific caves have lost 50-90% of their population. Funds have been established by the Indiana State University Center for North American Bat Research and Conservation and Bat Conservation International for specific study on white nose syndrome.

There are many theories at the moment as to why bats could be affected by this condition. Some suggest that warmer weather has caused bats to fly off-season, but doing this lessens their food supply. If bats aren’t hibernating, as they should, they may be more susceptible to disease because they’re starving due to lack of available insects in off-season periods. Others suggest the cause of white nose syndrome is likely as complicated as the problem it produces, and that many factors may be at work to cause the illness in bats, which has taken record tolls on bat population.