y first impression was that it was some odd kind of winged chimera with a weird gargoyle face.* After regaining whatever composure I had left, I went straight to the first Aussie I could find and demanded to know what strange beast I had just encountered. He laughed as he told me it was a fruit bat, sometimes called a flying fox. "Flying gargoyle is more like it!" was my semi-serious retort.
Intrigued by this new-to-me winged mammal that shares our globe with us, I set about to find out more as soon as my wife and I returned stateside. There are few bat biologists, I discovered, so the life of fruit bats has not been well-researched. Here is a glimpse of what we do know:
Fruit bats don't always roost in trees
"Flying gargoyle" Pteropus conspicil-latusFruit bat skeleton projects a fearsome image Fruit bats have four long fingers and a short thumb on each wing (see skeleton at right below). The wing consists of a membrane that is attached to the fingers and to the leg. Claws are located at the end of the second finger and on the thumb. These are used to pluck fruit from forest plants and trees.
- By detaching the fruit and carrying it away, they promote the distribution of plants. As they whisk their meal away, they spit out the seeds or pass them through their digestive tract and eliminate them elsewhere. Sometimes they simply crush fruit with their teeth, which are adapted for biting through hard skins, and only drink the juice, spitting out the rest.
- Feeding ranges can reach up to 40 miles. Due to their size, flying foxes must try to "land" in order to capture fruit, while smaller members of the species are able to grab fruit by flapping their wings and hovering in front of it. When it finds a meal, the flying fox often sort of "crashes" into the foliage and grabs for the fruit. It may also decide to snare a branch with its hind feet, letting the forward momentum swing it upside down. If it succeeds in this maneuver and is attached and hanging, the bat then pulls the fruit to its mouth with one of its hind feet or with the claws on its thumbs.
- They lick the nectar from flowers with their long tongues. In the process, pollen adheres to their tongues and face and is transported to the next flower, pollinating it.
- Their sense of smell and vision are very keen, but they don't navigate via echolocation as most other bats do.
- No more than one offspring is produced in late spring of each year. Females become fertile at the age of two.
- So far, flying foxes have not tested positive for the Ebola virus. Three other species of fruit bats have, but had no symptoms, making it highly likely that they are acting as a reservoir for the virus. Testing positive were Hypsignathus monstrosus, Epomops franqueti, and Myonycteris torquata.
During the day fruit bats roost in trees (not caves). They may roost in small groups or in large colonies. About half an hour or so after sunset they flock to a feeding site. During the next two- to three hours they are extremely active. They become quite raucous as they feed and chase one another. When two or more bats meet, they hit each other with their wings and scream loudly. (Click on the colony roosting photo at the right above to hear what they sound like and to see them in flight.) When they roost and feed in large colonies, they can become a nuisance, killing trees and pillaging farmers' fruit crops.
As night wears on, the bats calm down and begin to disperse. About one hour before sunrise, they return to their roost and fall asleep as dawn creeps over the horizon.
The Fear Factor
Fruit Bat Distribution
There are actually only 3 species of bats that feed on blood, and they all live in Latin America.
The fear of bats (chiroptophobia) is furthered by the natural startle response when an unsuspecting person comes upon a bat or when one flutters by in the darkness. Rabies is also a concern. People often fear bats because they worry about being bitten by one that is rabid. Only about 0.5% of all bats in the world carry rabies.
Click on map for more information
Are you ready for this? Click the button for a
really bad fruit bat joke (artist unknown).
*See Toni Leland's recent article, Griffins, Gargoyles, Grotesques, and Other Beasts: Garden Guardians
Images courtesy of Wikipedia
Post Script Bonus
After this article first appeared, I heard from Nick Edards, an Australian well-versed in all aspects of fruit bats (see his comments below). Here are three incredible links he made available:
©Larry Rettig 2009