New York Status: Endangered
Federal Status: Threatened
Description
The Chittenango ovate amber snail has a translucent shell with 3 1/2 whorls on an elongated spire. Maximum size is about 0.9 inch (23 mm). The shell is glossy, off-white to pale or pinkish yellow and is marked with growth wrinkles and lines. The soft body of the snail is a pale, translucent yellow. The outer covering of the soft parts, called the mantle, is pale yellowish-olive and is often marked with black streaks and blotches. A prominent dark blotch can be found on the upper side of the foot.
Life History
This species is a terrestrial snail with a life span of about two and a half years. It is hermaphroditic (individuals having both male and female reproductive organs) and mates from April until June. Four to fifteen transparent, jelly-like eggs are laid about a month after mating. The young snails hatch in 2-3 weeks, measuring 0.04 inch (1 mm).
Chittenango snails apparently feed on microscopic algae and other species of microflora that grow on the rocks and vegetation which occur in the spray zone of the waterfall around which they live. They ingest a lot of calcium carbonate for shell development. Adapted to relatively constant environmental and climatic conditions, including a clean water supply, the snail is intolerant of sudden changes.
Distribution and Habitat
The Chittenango snail appears to have evolved during the Pleistocene epoch. Similar snails occurred in isolated pockets from Tennessee to Ontario and as far west as Iowa and Minnesota. Although fossil shells similar in appearance to the Chittenango snail have been found at other sites, live specimens can be found at only one location in the entire world: a 100 foot high waterfall in central New York. The waterfall lies within Chittenango State Park which is administered by the New York State Office of Parks, Recreation and Historic Preservation.
The preferred habitat is the vegetated slopes adjacent to the waterfall, with their moderate climate and high humidity. Chittenango snails are found among patches of touch-me-nots, mosses, and liverworts.
Status
The Chittenango ovate amber snail was described as being "abundant" when it was first discovered at Chittenango Falls in Madison County in 1905. The total population was estimated at less than 500 individuals in 1982; however, and had declined to fewer than 25 by 1990.
The Chittenango snail is listed as Endangered because of its extremely limited range and apparently declining numbers since discovery. Its existence at only one site makes it extremely vulnerable to a catastrophic event which could destroy the entire population. Factors thought to adversely affect the snail include water pollution, inadvertent habitat disturbance by humans, environmental sensitivity, and the introduction of a closely related pest species. Most of the Chittenango Creek watershed is used for agriculture, with fertilizers, herbicides and pesticides entering the drainage. In the winter months, road salt causes high salinity. Although water quality appears to be generally high, the effects of short-term pulses of polluted runoff from these agents may be deleterious to the population.
In 1984, a closely related snail, similar to Succinea putris of Europe, was found at Chittenango Falls. Probably introduced to the falls by accident, this snail is apparently out-competing the Chittenango snail. Recent censusing of the snails indicates the pest species outnumbers the Chittenango ovate amber snail by at least 50 to 1.
Management and Research Needs
The New York State Department of Environmental Conservation took a lead role in initiating and completing a recovery plan for this species. In March 1983, the U. S. Fish and Wildlife Service gave final approval to the Chittenango Ovate Amber Snail Recovery Plan. This plan provides a detailed outline of activities essential to the protection and perpetuation of a self-sustaining colony.
Recovery of this species, in part, requires strict protection of its habitat and a reduction of contaminants entering the creek. The Chittenango State Park receives more than 100,000 visitors annually. Park managers direct visitors away from the critical habitat area and the immediate area of the falls is relatively inaccessible. Despite these safeguards, some trampling and overturned rocks have been observed. Any disturbance can severely affect reproductive success.
Ensuring this unique species continued existence and hopefully augmenting its population requires a captive colony of snails. Efforts to establish a captive colony of Chittenango snails began in 1992. A collection of four adult snails produced approximately 40 hatchlings. As expected, initial results indicate that Chittenango snails do not reproduce or grow as quickly as the pest species of snail, but they are at least encouraging in that the species can be maintained and produced in captivity.
Additional detailed studies on the ecology and life history of the Chittenango ovate amber snail are needed.