denise
11-24-2008, 10:04 PM
Quick Guide to the Texas blind salamander, Eurycea rathbuni:
Type of Animal: Salamander, part of the amphibian group
Type of cave dweller: Troglobite, a cave dweller
Distribution: A few caves of the Edwards Aquifer near San Marcos, Texas.
Conservation Status: Endangered
The Texas blind salamander, Eurycea rathbuni, is a rare troglobite amphibian, only found in caves of the Edwards Aquifer near San Marcos, Texas. The Edwards Plateau is a complex system of springs and caves located at an elevation of 1800-2100 feet. The Texas blind salamander spends its entire life underground in the caves, but, from time to time, some unfortunate individuals get too close to the springs that lead to the topside world, and the strong flow of water propels them out into the river where hungry catfish await them.
The Texas blind salamander reaches up to 5 inches in length when fully grown. They appear white/translucent or even pink in colour, as they have very little skin pigment. They have very slender limbs, and a long tapering tail. Their eyes are vestigial (have no function) and are buried beneath the skin; sight is unimportant to these salamanders as they spend their entire life in complete darkness. Their external gills are bright red due to a rich blood supply, and readily absorb oxygen from the surrounding water.
The blind salamander is an active predator. They scour along the bottom of caves, moving their head from side to side, locating small prey by detecting water pressure waves created by animals in the still surrounding water. Their diet consists of tiny snails, shrimp, amphopids, and other small aquatic invertebrates.
http://www.scubadiver.cc/fishid/texasblindsalamanderfws_2.JPG
The Texas blind salamander, Eurycea rathbuni, showing white body, long tapering tail and red external gills
Photo courtesy of US Fish and Wildlife Service (http://www.fws.gov/)
Clear, clean water is an essential requirement of the Texas Blind Salamander. Unfortunately the quality of water in the already limited habitat range of the Texas Blind Salamander has deteriorated recently, endangering this species. As the human population increases in the area surrounding their delicate habitat, more and more water is extracted for drinking, are the spring outflows are reduced. Pollution, increased sewage discharge and increased use of fertilizers and pesticides threaten the remaining water quality.
More urbanization also means more impervious surface, which diverts rainwater that would normally recharge the aquifer. As water becomes more and more scarce, natural events, such as droughts, become more serious, and impact species more negatively than they normally would.
The Texas blind salamander was placed on the federal endangered species list in 1967, and has been the subject of intense study ever since. Since 1980, hundreds of salamanders were collected by the U.S. Fish and Wildlife Service for a captive breeding program at the nearby San Macros National Fish Hatchery. These captive salamanders are part of an important breeding population used to supplement the natural, limited population. This collection is critical to the future of the Texas Blind Salamander in the event a natural or human-caused incident completely destroys their natural habitat, and wipes the remaining wild specimens out.
http://www.scubadiver.cc/fishid/texasblindsalamanderfws_3.JPG
Close up of a specimen of a Texas blind salamander in the captive breeding programme
Photo courtesy of US Fish and Wildlife Service (http://www.fws.gov/)
http://www.scubadiver.cc/fishid/blindsalamander.JPG
Photo courtesy of TJ
Type of Animal: Salamander, part of the amphibian group
Type of cave dweller: Troglobite, a cave dweller
Distribution: A few caves of the Edwards Aquifer near San Marcos, Texas.
Conservation Status: Endangered
The Texas blind salamander, Eurycea rathbuni, is a rare troglobite amphibian, only found in caves of the Edwards Aquifer near San Marcos, Texas. The Edwards Plateau is a complex system of springs and caves located at an elevation of 1800-2100 feet. The Texas blind salamander spends its entire life underground in the caves, but, from time to time, some unfortunate individuals get too close to the springs that lead to the topside world, and the strong flow of water propels them out into the river where hungry catfish await them.
The Texas blind salamander reaches up to 5 inches in length when fully grown. They appear white/translucent or even pink in colour, as they have very little skin pigment. They have very slender limbs, and a long tapering tail. Their eyes are vestigial (have no function) and are buried beneath the skin; sight is unimportant to these salamanders as they spend their entire life in complete darkness. Their external gills are bright red due to a rich blood supply, and readily absorb oxygen from the surrounding water.
The blind salamander is an active predator. They scour along the bottom of caves, moving their head from side to side, locating small prey by detecting water pressure waves created by animals in the still surrounding water. Their diet consists of tiny snails, shrimp, amphopids, and other small aquatic invertebrates.
http://www.scubadiver.cc/fishid/texasblindsalamanderfws_2.JPG
The Texas blind salamander, Eurycea rathbuni, showing white body, long tapering tail and red external gills
Photo courtesy of US Fish and Wildlife Service (http://www.fws.gov/)
Clear, clean water is an essential requirement of the Texas Blind Salamander. Unfortunately the quality of water in the already limited habitat range of the Texas Blind Salamander has deteriorated recently, endangering this species. As the human population increases in the area surrounding their delicate habitat, more and more water is extracted for drinking, are the spring outflows are reduced. Pollution, increased sewage discharge and increased use of fertilizers and pesticides threaten the remaining water quality.
More urbanization also means more impervious surface, which diverts rainwater that would normally recharge the aquifer. As water becomes more and more scarce, natural events, such as droughts, become more serious, and impact species more negatively than they normally would.
The Texas blind salamander was placed on the federal endangered species list in 1967, and has been the subject of intense study ever since. Since 1980, hundreds of salamanders were collected by the U.S. Fish and Wildlife Service for a captive breeding program at the nearby San Macros National Fish Hatchery. These captive salamanders are part of an important breeding population used to supplement the natural, limited population. This collection is critical to the future of the Texas Blind Salamander in the event a natural or human-caused incident completely destroys their natural habitat, and wipes the remaining wild specimens out.
http://www.scubadiver.cc/fishid/texasblindsalamanderfws_3.JPG
Close up of a specimen of a Texas blind salamander in the captive breeding programme
Photo courtesy of US Fish and Wildlife Service (http://www.fws.gov/)
http://www.scubadiver.cc/fishid/blindsalamander.JPG
Photo courtesy of TJ