Monday, February 18, 2019

Saving Bats in the West

US Person has posted in the past about the deadly "white nose fungus" that is decimating bat colonies in the eastern US. {26.05.11}  Pseudogymnoascus destructans causes fuzzy white spots to appear on infected bats' muzzles and wings.  Biologists writing in a microbiology journal have called it "the most consequential wildlife diseases of modern times"  The disease has killed millions of bats and threatens a once abundant mammal with extinction. The loss of this little mammal could have consequences for man: bats play a critical ecological role as pollinators and insectivores.  However, some experts think attempts to immunize bats or isolate healthy colonies to prevent infections, "wrongheaded", or worse, a waste of money.  Disrupting bats during their hibernation period for treatment would add stress at a time when they are most vulnerable according to these laissez- faire experts.  So far an effective treatment for bats to resist the pathogen has eluded a host of agencies, non-profit organizations, and volunteers.  Exposing colonies to UV light is a possible solution.  UV kills the fungus in laboratory experiments, but deploying it effectively in the wild is another problem not yet solved.  The effect of such exposure on roosting bats is unknown.

The fungus, a probable Eurasian invasive species, was first discovered in a cave in Schoharie County, near Albany, New York in 2006. Since then it has spread to thirty six states and seven Canadian provinces wiping out entire colonies; an estimated six million bats have died.  Now the disease is infiltrating the West at the rate of one state per year.  It has already appeared on the eastern edge of the region, killing bats in Oklahoma, South Dakota and eastern Wyoming. Biologists are starting to enter caves and abandoned mines [photo, left] to locate affected colonies and study unaffected colonies to determine how they might resist the disease. Caves and mines peppering the Rocky Mountains are the redoubt of overwintering bats. The pathogen dehydrates them, causing them to wake from their torpor and deplete energy needed for their survival. Instead of waking once every three weeks or so to take care of business, such as mating, they wake every seven days to drink.  Bats use almost no energy while in torpor, but their too frequent arousal depletes their strict energy budget causing starvation.

Treating bats could produce unwanted results, such as killing beneficial microorganisms that could cause adverse chain reactions in their underground habitat.  Also, treated bats could become reinfected.  Biologists have considered putting food in their caves, applying chemical skin treatments, installing dehumidifiers and spraying with an organic anti-fungal agent made from wild pineapple stems.  Research goes on to find the best way to help our bats survive this deadly plague. [photos: credit New York Times]