Wednesday, May 16, 2012

Experience tiger salamander, one of the largest terrestrial salamanders in the United States.


Eastern Tiger Salamander Fact Sheet

Eastern Tiger Salamander
Ambystoma tigrinum

New York Status: EndangeredFederal Status: Not Listed

Description

Drawing of Eastern Tiger Salamander
The tiger salamander is one of the largest terrestrial salamanders in the United States. The biggest specimen recorded was 13 inches long. The average size ranges between seven and eight inches. It is stocky with sturdy limbs and a long tail. The body color is dark brown, almost black, and irregularly marked with yellow to olive colored blotches. The only other salamander with which it might be confused is the smaller spotted salamander (Ambystoma maculatum). The spotted, however, has two rows of regular, yellow-to-orange spots running parallel down its back, as distinct from the irregularly distributed spots of the tiger salamander.

Life History

The tiger salamander spends most of its life underground, as do other members of the group referred to as "mole salamanders." On Long Island, it emerges from its burrow in February or March to migrate at night, usually during rain, to the breeding ponds. After a brief courtship which consists of the male pushing his nose against the female's body, eggs are laid in a mass and attached to twigs and weed stems under water. The female may deposit one or more egg masses containing 25-50 eggs per mass. Hatching occurs after approximately four weeks and the larvae remain in the ponds until late July or early August. After this time, the larvae transform into air breathing sub-adults measuring between four and five inches, and leave the ponds at night during wet weather to begin their underground existence. It takes four to five years for the salamanders to reach sexual maturity and they may live for 12-15 years. The tiger salamander eats invertebrates and small vertebrates.

Distribution and Habitat

The eastern tiger salamander ranges along the east coast from southern New York to northern Florida, west from Ohio to Minnesota and southward through eastern Texas to the Gulf. Historically, Albany is cited as being the northernmost point of this species' range along the east coast. The only two specimens recorded (1835, 1836) from this area may in fact have been brought into the area accidentally via the Erie canal. The tiger salamander inhabits sandy pine barren areas with temporary or permanent pools for breeding. In New York,the tiger salamander is found only on Long Island with most of the known breeding colonies restricted to the central Pine Barrens. In the absence of natural pools or ponds, it may breed in man-made depressions filled with water.

Status

Loss of habitat has been responsible for the extirpation of this species from heavily developed western Long Island. Recent surveys have identified about 90 breeding ponds in New York, confined to eastern Nassau County and Suffolk County. Its status at these remaining sites is tenuous because of pesticides and other contaminants, threat of development, and other land use patterns.
Disturbance at ponds, introduction of predatory fish into permanent pools and expansion of bullfrog populations threaten annual reproduction. Recreational activities, especially off-road vehicles further impact breeding sites and year round habitat. Increased construction of roads has also bisected the habitat, jeopardizing migrating adults.

Management and Research Needs

Intensive surveys were conducted to determine the distribution of this species in New York. Breeding ponds have been designated as Class I wetlands. A five-year program to reintroduce tiger salamanders to an unoccupied historic site in Nassau County by transplanting egg masses was initiated in 1987 but has had limited success. A radio telemetry study, funded by Return A Gift to Wildlife was started in 1990 to study the biology and upland habitat requirements of this species is needed in order to develop appropriate management strategies.
The construction of salamander tunnels under roadways separating upland habitat from breeding ponds is being planned.

Additional References

Bishop, S. C. 1943. Handbook of Salamanders. Cornell University Press, Ithaca.
Conant, R. and J. T. Collins. 1998. A Field Guide to Reptiles and Amphibians of Eastern and Central North America. Third Edition Expanded. Houghton Mifflin Co., Boston.
Harding, J. H. 1997. Amphibians and Reptiles of the Great Lakes Region. The University of Michigan Press, Ann Arbor. 378 pp.
Pfingsten, R. A. and F. L. Downs. 1989. Salamanders of Ohio. Bulletin of the Ohio Biological Survey. Vol. 7 No. 2. College of Biological Sciences The Ohio State University, Columbus.
Petranka, J. W. 1998. Salamanders of the United States and Canada. Smithsonian Institute Press, Washington and London.
Stine, C. J. 1984. The Life History and Status of the Eastern Tiger Salamander, Ambystoma tigrinum. Bulletin of the Maryland Herpetological Society. Vol. 20 No. 3.
Vogt, R. C. 1981. Natural History of Amphibians and Reptiles of Wisconsin. The Milwaukee Public Museum, Milwaukee, Wisconsin.
Map adapted from Conant and Collins (1998), Harding (1997) and Petranka (1998)

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