Symbol of Fear? Only If You’re an Insect
by Kevin Mack, PAWS Wildlife Naturalist
On October 25th, 2005, we received a very special patient at the PAWS Wildlife
Rehabilitation Center. For some reason, animals of his kind are often used as
symbols of fear and dread, especially during the Halloween season. In reality,
unless you are a moth, mosquito or other night-flying insect, the thought of
this animal should illicit feelings of appreciation and awe rather than fear.
That being said, let’s take a closer look at this amazing “creature of the night.”
Meet the Hoary Bat. According to information from Bat Conservation International,
the Hoary Bat has the widest range of any North American bat species. They range
from Argentina and Chile all the way to northern Canada, and a subspecies is even
found on the Hawaiian Islands. They are migratory, and populations from the northwest
primarily winter in southern California. This particular bat was found in front of
a door right here in Lynnwood. He was on the ground, and there was some concern that
he might be sick or injured, so Lynnwood Animal Control captured him and brought him
to PAWS for assessment. These photos were taken during the bat’s initial physical
examination. If you ever come across a bat that you feel may be sick or injured, please
do not touch or disturb the animal. Call PAWS, or a wildlife rehabilitator in your
area for further instructions.
Even though Hoary Bats are fairly large compared to other North American bats,
you can see in the photo how tiny he is in comparison to the human hand that
holds him. In this photo, you can also see the leathery "patagium" that creates
the flight surface of the bat’s wing. Bats belong to the order Chiroptera, which
translates to “hand-wing." If you look closely at the wing, you will realize how
fitting this name is. A large portion of the patagium is stretched between elongated
bones that are homologous to our fingers.
Here is a close-up of the back of the bat’s “hand” at the wrist joint. Hold your
right hand up in front of you with the thumb pointed down to get an idea of how
the photo is oriented. The clawed digit at the bottom of the photo is the equivalent
of your thumb. Note the other four digits, and how they support the flight surface
that stretches between them.
This view of the underside of the left wing shows the beautiful blond fur that
extends over part of the flight surface.
Although somewhat blurry, this photo shows the "uropatagium," a flap of skin that stretches
between the bat’s legs and tail. The uropatagium acts as a rudder, helping the bat to maneuver
while in the air. It is also sometimes used like a net to scoop insects out of the air and into
the bat’s mouth. Note the curved claws on the end of the toes. These enable the bat to easily
cling to tree trunks and other rough, vertical surfaces. Bats cling to surfaces with their heads
pointed downward. This allows them to simply release their grip, spread their wings and “drop
In this front view, you can see a nearly heart-shaped ruff of light fur around the
bat’s head. It stands out in sharp contrast to the Hoary Bat’s silvery-gray body
fur. His eyes are so small that they are difficult to see from this angle, but as
his large ears attest, he often relies more heavily on hearing to assess his surroundings.
The bat’s mouth moved constantly during his examination, emitting both warning vocalizations
that we could hear, and likely other sounds that we could not. Many of the vocalizations
that bats produce are outside of the range of human hearing. In a process called echolocation,
they project these high-frequency sounds in front of them and are able to avoid obstacles,
detect prey, and in many cases even determine the texture of objects by the sound waves they reflect.
From this angle, you can clearly see the bat’s eye. Contrary to popular belief, bats
aren’t blind. If you include both his eyes and his ability to echolocate, this bat
can “see” using either reflected light or sound. His teeth may look intimidating in
this blown-up photo, but that impressive dental work is used solely for grasping and
chewing insects. This view also gives you a good look at the position of the bat’s
“thumb” when the wing is in a folded position. The claw at the end of this digit
assists the bat in climbing.
No injuries were discovered during the Hoary Bat’s examination, and he was determined
to be in excellent health. It’s hard to say why he ended up on the ground in front
of a door, but perhaps he had been disturbed from a nearby day roost. After a quick
indoor test flight to ensure that he behaved normally in flight, wildlife rehabilitator
Emily Sullivan attempted to place him on a tree trunk outside.
Apparently the trunk was not to his liking (actually, the trunk was probably less of an
issue than the humans nearby). The bat flew away, and after an amazing high-speed flight
through the trees he came to rest about 35 feet up the trunk of a nearby alder. There, he
passed the remaining daylight hours and presumably continued his southward migration once
Wild animals released between October 17th and October 31st, 2005:
- 5 Black-tailed Deer
- 2 American Robins
- 1 House Sparrow
- 1 Glaucous-winged Gull
- 8 Raccoons
- 8 Northern Flying Squirrels
- 1 Mallard
- 1 Dark-eyed Junco
- 1 Steller's Jay
539 wild animals have been released since the beginning of 2005.
Thanks to all of you for helping to make these releases possible!
All rights reserved. ©2005 Progressive Animal Welfare Society
Northwest leader in protecting animals since 1967, the Progressive
Animal Welfare Society (PAWS) shelters homeless animals, rehabilitates
injured and orphaned wildlife, and empowers people to demonstrate
compassion and respect for animals in their daily lives.