Tag Archives: bats

In Search of Darkness

Can you still see the Milky Way at night?  It is a beautiful sight; not something to be taken for granted in our artificially lit world.  You look outside and see a dark night; but just a few years ago, Oakridge was an undeveloped 4400 acres, a darker place than it is now.   We have in our power, as a community, to work to keep light pollution down within our boundaries and contribute to our overall environment.

I’ve just finished a new book from Paul Bogard titled The End of Night, Searching for Natural Darkness in an Age of Artificial Light.   He covers all aspects of the increasing artificial light, often poetically.   But he raises major concerns about the effects, not only to humans, but to all our wildlife in “five primary areas: orientation, predation, competition, reproduction and circadian rhythms.”

The (John) Bortle Scale of ranking dark skies ranges from 9 to 1.  Texans probably need to drive to Big Bend National Park to get close to a dark enough night to rate a 1, or 2.   A Class 1 is described as “a sky so dark that ‘the Milky Way casts obvious diffuse shadows on the ground“.    http://www.stellar-skies.com/#!thenightskies/c44

It is a more complicated subject than you might think at first glance; an important subject I think.  Maybe as members of the community of Oakridge, we should educate ourselves to the global effort to work with the issue.  And do what we can.     http://www.darksky.org/

http://conservationreport.files.wordpress.com/2009/03/artificial-light.jpg

A quote from Wendall Berry:  “To go in the dark with a light is to know the light.  To know the dark, go dark.  Go without sight and find that the dark, too, blooms and sings, and is traveled by dark feet and dark wings.”

The Importance of Bats

For a very long time, I have been totally fascinated with bats.  We have had some great experiences with bat watching; even gone into an undeveloped Texas cave for guano and stayed to experience the emergence with no one around, standing there, waving our hands above our heads as they flew toward us, missing us every time.  It is awe inspiring.

Our experiences have been with Mexican Free-tailed bats Tadarida brasiliensis, the most common Texas bat.  Probably the species you watch from your porch on summer evenings.  They are here from about February and most begin to leave for Mexico now, in August.

The 20 million or so Mexican Free-tailed bats of Bracken Cave, the world’s largest known colony, eats a quarter of a million pounds or more of insects nightly, covering thousands of square miles.  These amazing creatures emerge each evening, climbing to more than 10,000 feet, and can catch tail winds that can drive them to speeds of over 60 miles per hour to distant feeding grounds.   It almost can’t be stated enough how bats are by far the most important controllers of night flying insects, even mosquitos.

To my surprise, I have learned that joining the Mexican Free-tailed bat in our skies are 8 additional species:  Big Brown bat Eptesicus fuscus, Silver-haired bat Lasionycteris noctivagans, Eastern Red bat Lasiurus borealis, Hoary bat Lasiurus cinereus, Northern yellow bat  Lasiurus intermedius, Seminole bat Lasiurus seminolus, Evening bat Nycticeius humeralis  and Tri-colored bat  Perimyotis subflavus.

Did you know:  Bats are highly intelligent and even trainable?  World-wide, there are over 1000 extremely diverse species?  Millions of bats are dying from White-nose Syndrome?  Some species hibernate rather than migrate?  Some species are vital pollinators?  Some feed on fruit or nectar?   Not all species roost in caves?  There are no blind bats?  They do not become entangled in people’s hair?  They pose less of a threat to human health than do household pets?

Bat Conservation International was founded in Austin in 1982 by Dr. Merlin Tuttle.   Do check out this excellent site for all things related to bats   http://batcon.org/