Thursday, August 6, 2009
This year I raised baby bats, and so had the opportunity to observe more closely these curious micromammals. They are so micro, I had to take pictures in order to sketch them!
Feeding them milk with a micropipette, while looking at how they move and respond, was a fascinating experience.
This little guy is a pup of Kuhl's bat. As adults, they can be identified by a white line on the edge of their wing membrane.
Bats belong to the Order Chiroptera, from the Greek cheiro, hand, and ptera, wing. They have a thin, transparent membrane, called the patagium, which extends from the neck and across the fingers and, in most species, includes the tail as well. Like us, they possess 5 fingers, but their bones are lighter than those of other mammals. The clawed thumb is free, and it is used for climbing around the roost.
Bats have good vision, but depend on echolocation to navigate and hunt down their prey. When the bat emits a sound wave, he than listens for the returning echo, which conveys important information. If the echo reaches the right ear before the left, the insect is to the right, while the intensity of the echo carries information on the size of the insect. When the insect is moving away from the bat, the returning echo has a lower pitch.
The many folds present in the bat's ears help the animal determine the insect vertical position.
With a body length of 3 and half inches and a wing length of 2 and half inches at the most, the European Free-tailed Bat, on the left, is one of the largest bat species to be found in Europe, Asia and Africa.