|
|
|
|
|
Click on image to enlarge. 
| |
| Scientific name: Chordata: Mammalia: Chiroptera: Vespertilionidae: Common Name: Bats Country: USA Photographer: E. M. Barrows Identifier:
Additional Information: This page is dedicated to the memory of Dr. Charles O. Handley, bat specialist. Figure 1. A view of the marsh of Huntley Meadows Park at sunset. Figure 2. Carolyn Gamble searching of feeding bats in the air with her bat detector. Figure 3. Ditto. Bats Likely to Be in The Washington, D.C., Area (according to Charles O. Handley, Jr., 2000) Plain-nosed Bats (Vespertilionidae) Eptesicus fuscus, Big Brown Bat Lasionycteris noctivagans, Silver-haired Bat Lasiurus (New World Tree Bats) Lasiurus seminolus Lasiurus intermedius, Northern Yellow Bat Myotis (Mouse-eared Bats) Myotis grisescens, Gray Bat Myotis lucifugus, Little Brown Myotis Myotis keeni, Keen Myotis Myotis subulatus, Small-footed Myotis Myotis leibii (was synonymous with M. subulatus) Myotis septentrionalis Pipistrellus (Pipistrels) Pipistrellus subflavus, Eastern Pipistrel Plecotus (Big-eared Bats) Plecotus rafinesquei, Refinesque's Big-eared Bat Plecotus townsendii, Townsend's Big-eared Bat Bats of Huntley Meadows Park, Virginia On the warm evening of 2 May 2001, Mr. Carolyn Gamble, Site Manager of Huntley Meadows Park, energetically addressed Friends of Dyke Marsh regarding her favorite creatures — Bats. She began her work with bats in the 1970s on Barro Colorado Island, Panama, with Dr. Charles O. Handley. She presented an overview of bat biology and bats of the world. After her talk she took us outdoors to search for bat sounds with her bat detector. We went outside at about 9 p.m., and we able to detect only one hunting bat, probably due to the lateness of the hour. Ed Eder (President, Friends of Dyke Marsh)told us that he had up to 52 Big Brown Bats roosting under the shutters of his home. No one in the audience of about 30, had success with bats' using bat boxes. Bats Known from the Park Big Brown Bat Eastern Pipistrel Hoary Bat Little Brown Bat Red Bat Silver-haired Bat Bats Possibly in the Park Evening Bat Keen's Myotis A Visit with Bat Researcher, Dr. Charles O. Handley, Jr. (8 February 2000) Most bats never contact Humans. These flying mammals consume billions of insects annually, pollinate some plant species, and disperse seeds of some plant species. Bats are highly valuable members of ecosystems. Dr. Handley, began work at the Smithsonian as a curator of birds in 1950, but soon switched to bats. As a teenager, he published several articles on birds, and later the book Wild Mammals of Virginia in 1947. In 1950, his assignment was mammals of the Western Hemisphere and marine mammals of the world. In 1956, Charles begin the project Mammals of Panama. In the early 1970s, he started specializing on bats. In 1975, he began a study of bats on Barro Colorado Island, Panama. On this 6-square-mile island, Charles and Dr. Elisabeth K. V. Kalko estimate there are 15,000 fruit-eating and 1000s of insect-eating bats in 60 species. He kindly showed us some of the Smithsonian Bat Collection, by far the largest in the world on 8 February 2000. Although most people have essentially no interactions with bats, bats are 25% of the some 4,000 mammal species that live on Earth; 50% of living mammal species are rodents. Bats are more laborious to study than many other kinds of organisms because they are difficult to observe and people have not discovered the roosting places of many species. Researchers can capture many kinds of bats with mist nets. They spread these nets out in the air in places where bats fly. Japanese workers invented these nets to capture songbirds for human consumption and Dr. Handley said that they over-exploited many songbird species. All songbird species are probably perfectly palatable, except for a few species in New Guinea. Dr. Handley estimated that there are about 10 bat species in the WDC Area; only four species are common residents. In contrast, Barro Colorado Island, Panama, which is smaller than WDC has about 60 species. There are 46 species in all of North America north of Mexico. Charles is working on a book of bats of Amazonia which has 150 species. He invented a method of preparing bats by removing their wing bones. This allows one to fold bats wings and produce space-saving specimens. Museums around the world are using this technique. It takes a person about 45 minutes to prepare a specimen with wing-bone removal, and about 10 minutes to make a traditional preparation. We were amazed how one can fold and unfold a boneless bat wing many times with no apparent wear on the wing. I guess bats do the same thing many times with boned wings. The bat collection is in large white cabinets stacked two high. The specimens include skins and skulls. A felt strip that used to have arsenic lines the opening of a cabinet. OSHA no longer allows the Smithsonian to use paradichlorobenzene in the cabinets. Technicians go through each cabinet twice per year. If a technician finds living insects, s/he places the case in question into a plastic bubble and gasses the unwitting insects with carbon dioxide which kills them, without using dangerous pesticides. Bats are in two main groups Megachiroptera (Megabats) and Microchiroptera (Microbats). Researchers debate whether bats arose from one ancestral stock (shrew-like mammals), or two stocks (shrew-like mammals and mammals similar to Flying Foxes). Charles thinks that the Megabats arose from a frugivorous dermopteran-like ancestor (Flying-lemur-like ancestor); the Microbats, from an insectivorous, shrew-like ancestor. All bats have five fingers typical of mammals. Megabats have two clawed fingers per wing; Microbats, one clawed finger per wing. Teeth of microbats closely resemble those of shrews. If Bats have two different ancestral stocks, that is they are diphyletic, then flight evolved twice in Bats. In the category of smallest mammal are the Bumble-bee Bat (Craseonycteris thonglongyai) of Thailand, and a shrew Suncus etruscus (from the Mediterranean through Pakistan and Southeast Asia). An adult individual of one of these species weighs less than a dime! Dr. Handley showed us a Ghost Bat (with white fur), Fruit-eating Bat (Megabat), leaf-nosed bats, and a series of nectar-eating bat species with snouts of different lengths (a fine evolutionary progression). He also showed us a fish-catching bat with sharp, fish-hook-like claws and its close relative, with a smaller "tail membrane" and smaller claws, that catches insects, and only very occasionally fish over the water. He did not let us pet a dead bat so that we would not soil it with our finger oil, but did allow us to touch the sharp claw tips of a Fishing Bat and the sharp teeth of another bat. The oldest known bat is a 40-million-year-old fossil. There are no known fossils of intermediate forms between bats and their non-bat ancestors. An insectivorous bat catches a flying insect its wing tips, flips it into its tail pouch, and gobbles it up. Fruit-eating bats find fruit by sniffing it out when it is under leaves and by echolocation when it is dangling in the open. As an aside, we discussed venomous mammals. Only two mammal species produce venom, the Duck-billed Platypus (only mature males, from a hind-foot spur), and Short-tailed Shrew, Blarina brevicauda. These Shrews paralyze prey, such as arthropods and mice, with their venom. They are very common in the WDC Area. Charles once let a Short-tailed Shrew bite his finger. The animal injected its poisonous saliva and caused his finger to burn. His metacarpels turned yellow, and his wrist burned as well for several hours. Dr. Handley died in June 2000. (I thank Charles for help with this summery of our visit. E. M. Barrows, 2000 02 08 Tuesday. Updated 2001 05 03 Thursday.) References Bat Conservation International Please click here to go BCI Graham, Gary L. 1994. Bats of the World. Golden Press, New York, NY. 160 pp. Huntley Meadows Park. 2000. Please click here to go to Huntley Meadows Park Reader's Digest Association. 1971. Fascinating World of Animals. Reader's Digest Association, Inc., Pleasantville, NY. 428 pp. |
