Wednesday, August 25, 2010

The Bats of Gotham

"Twinkle, twinkle little bat!
How I wonder what you're at!
Up above the world you fly,
like a tea-tray in the sky."
~ Lewis Carroll

Let’s say it’s a warm summer night and you decide to point a Bat Signal toward the skies above Manhattan. What will you see? Why, you will see bats. Lots of bats, all darting about in the darkness in their slightly ungainly way. They’ll be minding their business, not flying into your hair. They’ll be dining alfresco on pestilence-bearing mosquitoes, doing humanity a huge favor. You simply need to know what to look for.

Discovering what to look for is one reason why, at 8:30 p.m. on the last Friday in July, a night when the moon was almost full...oooOOOOoooo...I joined twenty-five other curious people on a bat walk in Central Park. 

 A Central Park bat (the pale color is due to the photo flash — the bat is brown). 
 Photo by Matt Grayson

The walks, which have taken place three times each July since 2004, are sponsored by the American Museum of Natural History (AMNH). They are led by Brad Klein and Danielle Gustafson, founders of the NYC Bat Group, whose mission is promoting the scientific study and conservation of bats while also encouraging more fondness and less fear of the little critters. On the night I went, we were also accompanied by AMNH Intern Max Engel-Streich.

As we waited on the museum’s steps for the full group to assemble, one of the city's many red-tailed hawks watched from a nook in the Beresford apartments across the street. Soon, as the sky grew darker, the first bats flew out of the eves and overhangs of the Upper West Side in search of a meal. We — a motley crew of adults, preschoolers, grandparents and one teenager — set off to join them, following Brad and Danielle down Iphigene’s Walk into the park. Our destination was herb-scented Tupelo Meadow, where we sat in the grass under a patch of open sky, a canopy of trees all around us. We watched bats fly overhead until it grew too dark to see them and used bat detectors — which amplify the bats' echolocation calls — to listen in as they hunted in the night.

Later, I found this video of bats hurtling above someone’s garden — it was a bit like this. 

Bat Truth v. Bat Fiction
Most of us grew up learning a lot of bad information about bats. The Central Park event is not just a bat walk but also a fact-filled bat seminar, where Brad and Danielle try to replace myths with truths. Some basic bat facts:
  1. Central Park is home to Vesper bats. Three species are common: big brown bats, little brown bats and red bats. (It’s true, bats seem to have been named by a literal-minded three-year-old.) Three other species — northern long-eared, silver-haired and hoary bats — are also known to frequent the park.
  2. Bats are not rodents; they are members of the order Chiroptera and are genetically closer to primates (including humans) than to mice. 
  3. Bats are not blind; in fact, they see fairly well, but echolocation helps them hunt their tiny airborne prey at night and avoid those who would prey on them.
  4. Giving new meaning to the term “old bat,” bats live a long time, with the oldest on record reaching 39. 
  5. Bats reproduce very slowly, normally giving birth to one offspring a year.
  6. Bats are not creepy. Consider mother bats — such good moms. Mothers-to-be roost together during their two-month gestation period to keep each other warm. The little ones — called pups (yes, just like dogs) — live on their mothers’ milk until they’re ready to fly, which these little prodigies can do as soon as three weeks after they’re born.
  7. Bats are not a nuisance, they are a blessing. For one thing, they eliminate tons upon tons of mosquitoes every year. According to Bat Conservation International, a single little brown bat can “catch more than 1,000 mosquito-sized insects in just one hour.”
  8. While it’s true that some bats are vampires who live on blood, none are Count Dracula, and no vampire bats live north of Mexico. 
  9. Less than half of one percent of bats ever contract rabies. But wait — you say you've just read a frightening article about rabid vampire bats biting people in Peru? It's true, and as this article in New Scientist points out, experts believe it's a side-effect of deforestation. But once again, there are no vampire bats north of Mexico. Bats in these parts are docile little insect-eaters, like this fuzzy fellow.
 A silver-haired bat snuggled up for a snooze on a tree in Central Park.
Photo by Ed Lam
    Help! Bats Need a Superhero
    Right now, several species of bats — led by little brown bats — are facing extinction, and the most urgent problem is a fast-moving disease called White-nose Syndrome, which affects bats that hibernate in caves (as about half of all North American bats do). First discovered in 2006 in a single cave near Albany, New York, White-nose Syndrome has already spread to 14 states and killed over 1 million bats. A new study by Boston University predicts that 99% of little brown bats in the Northeast will be gone in twenty years.

    That finding moved the New York Times to publish an editorial calling for a sharp increase in funding for White-nose Syndrome. As the Times said, “Without [bats], the balance of nature will be changed, with potentially significant impact on agriculture and forestry, which have always depended — almost without knowing it — on the role of insectivorous bats.”

    Because some evidence suggests that cave enthusiasts have unwittingly spread the disease, the U.S.  Forest Service has closed western caves and mines to humans for at least a year.

    For more information on bats and White Nose Syndrome, visit the Bat Conservation International website.

    "On the bat's back I do fly
           After summer merrily."
    ~ William Shakespeare, The Tempest


    1. This was wonderful—educational, entertaining, and the first things I've read that made me want to cuddle up to a bat. Thank you! I'm adding the bat walk to my list of New York must-dos.

    2. Thanks, Susan. They're incredibly cool animals. Join the NYC Bat Group on Facebook so you'll know when the tickets go on sale.

    3. Magnificent article. I LOVE THIS, MICHELLE. Thank you so much. Love the video. Love the bat facts. Love bats, as a matter of fact. We need to save these glorious, sweet creatures who exemplify the danger of judging anything too soon or too shallowly. I hope we save these bats; it's *time* to save them, it's time to love them, or failing that, respect and honor them.

      The photo of the furry bat snoozing on the tree: Do they do that? Was that a daytime shot? I didn't know they snoozed in that manner.

    4. Hi Kcecelia,
      Very glad you liked the article and I agree, we definitely need to save them.

      About the bat on the tree: Bats do many things we're only just learning about, including resting in trees. I learned on the bat walk that some even hibernate under loose bark. Very little scientific research has been done on bats. We don't even know where the migratory bats of New York spend the winter. I hope the current extinction crisis will will motivate more scientists focus on them.

    5. What a marvellous post — thanks, Michele. I've always been fond of bats. They used to flit about the house where I grew up, so I realised at an early age what amazing creatures they are, and how sadly misrepresented. More recently, but not recently enough, I attended bat walks in my current city. It's a lovely way to spend an evening.

      To add to your fine collection of links, I offer Thomas Nagel's famous essay.

    6. Thank you, Stan. I had never read Nagel's essay, but having just read it quickly I plan to read it again, probably several times. What a wise man; the law needs more like him (and the financial industry needs an army).

      His discussion of our inability to understand what it is like to experience bat sonar made me think of proprioception. Although it's a human trait we depend on it for so much, I don't think we understand it, either. Such a lot to discover!