The spring peepers chorus at full volume and can be heard from my front deck several hundred yards from the vernal pool symphony. It is twilight and I am trying to relax and take in the night as I sip a glass of red wine. As I am sitting here I see a small bat darting around in the sky in front of me. The bat’s flight direction changes constantly and erratically as he locates his prey with sound waves. The insect population is really just starting to emerge and so the bat has to work hard for a normal night’s meal. This amazing mammalian athlete is a wonder to observe. Few creatures have adapted better to fill a niche in the natural world.
Bats in New England are in great peril. White nose syndrome, the name given to the disease that is killing bats by the thousands, is rampant here and is apparently spreading south. The name of the disease comes from the little white ring that is found in the vicinity of the bat’s nose. The white ring is caused by a fungus. It is unclear if this fungus is a symptom of a disease or the actual cause of the bat’s demise.
Bat’s that hibernate together in large groups primarily in caves and old mines are being devastated by this disease. First discovered several years ago in a large cave in the Adirondacks it has spread into at least six northeast states and has also been noted in Virginia and West Virginia. The infected bats seem to burn through their entire fat reserves while hibernating before the end of winter. They are so desperate for food that they have been observed in daylight on a cold winter’s day looking for insects. I have read that some caves have lost 90% of the hibernating bat population!
In 2008 near the Deerfield River in Rowe, Massachusetts I observed a bat flying around at 2 PM in February. The bat seemed very disoriented and crashed into the snow on the ground several times. I did not approach the bat. I was worried that it had rabies. I remember thinking how unusual it was at the time. About a month later my wife encountered a bat on a trail in broad daylight while walking our two blood hounds. The bat was making hissing and high pitch screaming noises. It apparently could not fly and was in its final stages of life. I have heard dozens of stories such as these since last year. This winter I found a large brown bat dead in the snow in late February. It had the distinctive white muzzle that seems to be the tell tale identifier of this disease.
Several different bat species seem to be affected; little brown bats, big brown bats, Indiana bats (a threatened species), eastern pipistrelles, and northern long eared myotis. The fungus has been identified as a previously unknown form of Geomyces, typically a filamentous fungus found in soils. It is possible that this fungus has been in caves for years and gone unnoticed and only recently has begun to impact the bat populations.
Bats are a critical part of our ecosystem. They consume tons and tons of insects every summer. Some researchers think that insect populations could soar if this disease spreads much more. How ironic to weaken the bat population a predator on flying insects at a time when we are so concerned about diseases like West Nile Virus a very dangerous disease that can be spread by mosquitoes to humans.
Thus far researchers have no clue as to what the real cause of the disease is. One scientist is looking into some malady carried by bat mites, others are focusing on a potentially weakened immune system perhaps caused by environmental changes like the introduction on new insecticides, or secondary impacts from herbicides. No matter what the cause we have an enormous crisis that needs to be better understood. Time is of the essence, bats typically do not reproduce quickly. A female frequently raises one bat pup at a time. The major loss of many of these special mammals will take years to replace in perfect circumstances.
I had a thought about a possible cause of the white nose syndrome in bats. It came to me several weeks ago while reading an article about how antibiotics can be found in nearly every water resource we have. The use of veterinary antibiotics in farm animals, antibiotic hand cleansers, and improper disposal of human prescriptions have all led to antibiotics being found in many of our rivers, streams, lakes, ponds, and public water supplies. Many of the insects that bats consume have their early life cycles in aquatic environments. Is it possible that antibiotics have accumulated in these tiny insects and the bats consume these antibiotics as aside effect of their search for food?
Now, one might ask, what does this have to do with white nosed syndrome. By some coincidence I am an individual who has taken antibiotics off and on for years while trying to battle chronic lyme disease. One of the main side effects that I have encountered during these long phases of antibiotic use is rampant fungal infections. A primary side effect of many antibiotics are elevated fungal attacks. Is it possible that the bats are consuming insects that carry residue antibiotics and the bat cannot effectively fight the fungal infection? Certainly if bats were extremely stressed by trying to fight a major fungal infection it would use much energy which could account for the lost energy reserves that seem to be starving the bats during winter hibernation. This is just one possible theory of many. My instincts tell me that, in the end, we will discover that the bats are suffering from something that humans have put into the environment.
This sudden bat population reduction is eerily reminiscent of bee colony collapse disorder for which no cause has been uncovered. For more than five years honey bee colonies have collapsed throughout the world. This is a very serious problem because bees are one of our primary pollinators of flowers (both wild and commercial) of all kinds. It is quite a coincidence that two of our most important animal species are suddenly, emphasis on suddenly, experiencing population problems for no apparent reason.
Like the canary in the coal mine this is a serious warning that something is wrong. I am afraid that, like the climate change problem, few people will take these warnings to heart. I wonder if the average person gives thought to the possible devastating harms caused by the use of insecticides, herbicides, and antibiotics in food production and the impacts of these on the environment. Perhaps there are those who could think about this while they drive their SUV’s to the mall or super market.
The night is still young. The bats continue to forage fervently in the night sky. They are trying desperately to survive and I am left wondering why humans do not have that same instinct.
Written for www.wildramblings.com in May 0f 2009.