Chittenango Ovate Amber Snail

Succinea chittenangoensis

Description

The translucent shell of the Chittenango ovate amber snail is a slender egg-shape, about 0.8 in (2 cm) long, spiraling into three and one-half whorls. The color is a pale yellow to off-white. The shell surface is glossy and marked with growth wrinkles and lines. The color of the living animal is a pale, translucent yellow. The mantle (the outer covering of the soft parts) is pale yellow, tinted with olive, and often marked with black streaks and blotches.

This snail was first described as a subspecies of the more widespread ovate amber snail (Succinea ovalis ) and is referred to in many publications as S. o. chittenangoensis.

Behavior

The Chittenango ovate amber snail is a terrestrial species that prefers cool, sunlit areas of lush plant growth within the spray zone of waterfalls. The snail apparently feeds on microscopic plants and in some way ingests high levels of calcium carbonate for its shell development.

Sexually mature snails deposit up to 15 transparent, jelly-like eggs at the base of plants or in loose wet soil. The young snails hatch in two to three weeks and grow to maturity during the following spring. After two years, snails reach their full size. They then die, completing their life span in about two and one-half years.

Habitat

The ovate amber snail is found among the vegetation that covers slopes adjacent to a single waterfall. It is prominent among patches of watercress at the very edges of the stream. Most of the fall's spray zone is covered with patches of mosses and liver-worts. Skunk cabbages and angelica grow in the drier areas. Temperatures are mild and relatively constant, regulated by the waterfall mist. Humidity in the habitat is high.

Distribution

This species may have been widely distributed during the Pleistocene epoch throughout portions of Arkansas, Illinois, Iowa, Michigan, Missouri, Nebraska, and Ontario, as well as in New York. It was first discovered at Chittenango Falls in central New York in 1905.

One colony of this snail is known to survive at Chittenango Falls State Park (Madison County), New York. The population is divided into two groups living on either side of the falls. The total population was estimated in 1982 at less than 500 snails.

Threats

The primary reason for listing this species as threatened is its extremely limited range and its apparent decline since its discovery. Since it has been studied so little, actual causes for the decline are unknown.

Although the water quality of the stream is relatively high, these snails may be intolerant of trace amounts of chemical runoff. Most of the watershed of Chittenango Creek is used for agriculture, and fertilizers, herbicides, and pesticides enter the drainage. Winter road salt increases the salinity of the water.

Over 100,000 visitors come to the state park each year for recreation. Although the immediate falls area is fairly inaccessible, some trampling and dislodging of rocks has been observed. These disturbances can have a severe effect on the success of snail reproduction.

Conservation and Recovery

Recovery of this species will require strict protection of its habitat and reduction of pollutants entering the stream. State park personnel have developed a management plan to redirect visitors away from the habitat area and to restrict visitor access to the immediate vicinity of the falls. Further recovery actions will depend on the results of ongoing research into the snail's biology and habitat requirements. Biologists believe there is a good chance other populations of the snail may yet be found in central New York state.

Contact

U.S. Fish and Wildlife Service
Division of Endangered Species
300 Westgate Center Drive
Hadley, Massachusetts 01035
http://northeast.fws.gov/

References

Grimm, F. W. 1981. "A Review of the Chittenango Ovate Amber Snail, Succinea chittenangoensis. " Report. New York State Department of Environmental Conservation, Albany.

Hubricht, L. 1972. "Endangered Land Snails of the Eastern United States." Sterkiana 45:33-34.

Solem, A. 1976. "Status of Succinea ovalis chittenangoensis Pilsbry, 1908." Nautilus 90(3):107-114.

U.S. Fish and Wildlife Service. 1983. "Chittenango Ovate Amber Snail Recovery Plan." U.S. Fish and Wildlife Service, Newton Corner, Massachusetts.