Little Brown Bats&White Nose Fungus by Nora Tjossem - a podcast by Liz Hadly

Did you hear that?
That was the sound of the little brown bat - Myotis lucifugus. They’re everywhere on summer nights, and sometimes if you’re lucky, you’ll get to catch a glimpse of one as it chases mosquitoes through the trees.

But go outside right now if you want to, because it’s possible that within the next sixteen years, you won’t be hearing more than a recording. The little brown bats of North America are fighting a losing battle against an enemy we call...

Fungi?
That’s right. Or, in the scientific world, “Geomyces destructans.” This cold-loving fungus has been ravaging bat caves throughout North America since 2006, wiping out an average of 73% of an infiltrated cave population.

How does a fungus take out three out of every four bats?

Picture this: It’s late October. You’re a bat, hanging upside down in preparation for winter. This means you’ve eaten your fill of summer insects, you’ve huddled together with your family members, and you’re ready to shut down for the long, cold Northeastern winter ahead. You enter what’s called “torpor” - your body temperature decreases, you are using less energy and fewer resources, and you wake up sleepily every few weeks to replenish.

However, your body is now incredibly vulnerable. This is when the fungus strikes, eroding the exposed skin on your ears and wing membranes. You have what is known as White-Nose Syndrome.

What does this mean?
It means your hibernation plan has been compromised. Your time out of torpor increases, the balance of your systems is disrupted, and you’re prone to starvation or dehydration. Your chances of living are slim, and you’re likely to end up among thousands of your colony members dead on the cave floor.

Little brown bats are the most common of bats in North America, but they are now facing a threat that could lead to their eradication in the Northeast in under two decades. This means that the children of my generation’s college students may never get to see a little brown bat in New England. Also, insect populations could vastly increase. An individual bat eats about 3 to 7 grams of insects per night - that’s about the amount of ground coffee required for your 8 oz morning cup. Think of that many mosquitoes instead!

Social animals, such as bats, elephants, dolphins, and humans, are especially prone to rapid-spreading disease. It’s easy to be content with the current status of bat populations, but if we don’t pay attention and focus our research efforts now, a disease that first appeared only five years ago could lead to the eradication of our friend the little brown bat.

References
Blehert D, Hicks A, Behr M, Meteyer C, Berlowski-Zier B, Buckles E, Coleman J, Darling S, Gargas A, Niver R, Okoniewski J, Rudd R, and Stone W. 2009. Bat White-Nose Syndrome: An Emerging Fungal Pathogen? Science 323 (5911):227.
FOLEY, J, CLIFFORD, D, CASTLE, K, CRYAN, P and OSTFELD, R. S. 2011. Investigating and Managing the Rapid Emergence of White-Nose Syndrome, a Novel, Fatal, Infectious Disease of Hibernating Bats. Conservation Biology 25: 223–231.
Frick W, Pollock J, Hicks A, Langwig K, Reynolds D, Turner G, Butchkoski C, and Kunz T. 2010. An Emerging Disease Causes Regional Population Collapse of a Common North American Bat Species. Science 329: 679.
Kerth G, Perony N, Schweitzer F. 2011. Bats are able to maintain long-term social relationships despite the high fission-fusion dynamics of their groups. The Royal Society 2011 Feb 9; doi: 10.1098/rspb.2010.2718.
Bats About Our Town. Greg Salxa. 7 Dec. 2011
Photo: Marvin Moriarty/USFWS

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