Chittenango ovate amber snail
Encyclopedia
The Chittenango ovate amber snail, scientific name Novisuccinea chittenangoensis, is a species
of small air-breathing land snail
in the family Succineidae
, the amber snails. This species was discovered in 1905, and was reported three years later as a subspecies
of the oval ambersnail, Succinea ovalis. Several taxonomic
reviews took place in the subsequent decades until the end of the 1980s, when the Chittenango ovate amber snail was finally judged to be a distinct species Novisuccinea chittenangoensis, based on chemical and morphological data.
The Chittenango ovate amber snail is endemic to the Chittenango area of Madison County, New York
, United States
. There is only one population of this species at Chittenango Falls State Park
in central New York
, even though it was believed to have a broader range previously; based on fossil records, some authors argue that the distribution of this species may have been much wider in the past. In opposition to this, other authors argue that it is impossible to identify this species based on fossil records, because they only allow for examination of shell features. Shell features of species in this particular family of snails are usually not very distinctive.
Novisuccinea chittenangoensis has a small (an average of 20.9 mm in length in adult individuals), delicate, ovate shell of 3¼ whorls
, with deep sutures. The shell is almost translucent, and varies in color from a chalky pale yellow to white, with a glossy surface. Several internal organs of the animal can be distinguished through the shell's outer surface. The visible soft parts of the animal are of a pale subtranslucent yellow color, with different markings during distinct stages of development.
Studies on the ecology
of the Chittenango ovate amber snail are fairly recent. It is an herbivorous species which lives in the fresh spray zone of the Chittenango Falls, in partially sunlit areas with lush herbaceous growth. Several parameters appear to be influential in its habitat
selection, namely humidity
, substrate
, temperature, vegetation, and water quality. Novisuccinea chittenangoensis is a hermaphroditic species, and its mating
season is from May through July. It lays egg clusters, each one containing an average of 8 to 14 eggs, at the base of plants, under matted vegetation, or in loose, wet soil. Maturity
is reached in five to eight months, and its life span is roughly 2.5 years. Some of its predators include insect
s, amphibian
s, mammal
s, bird
s, and occasionally other snails.
Since the time of its discovery in 1905, there have been many attempts to estimate the population
size of this species. Results varied greatly, but the more recent ones suggest a very reduced number of individuals. This coupled with a very restricted distribution
have led to the listing of Novisuccinea chittenangoensis as an endangered
or threatened
species. Humans frequently invade its habitat, though such disturbances have been greatly reduced by preventive measures. Recent efforts in conservation include perpetuating the extant population at a baseline size as well as maintaining captive populations.
of Philadelphia. In 1908, Henry Augustus Pilsbry
reported the discovery, describing the snail as a subspecies of the widely distributed Succinea ovalis. Because of this, the Chittenango ovate amber snail is referred to in many publications as Succinea ovalis chittenangoensis.
Pilsbry placed Succinea ovalis in the subgenus
Novisuccinea
in 1948. Alan Solem
(1976) considered this snail to be merely a form of Succinea ovalis, citing similarities in genitalia and radula
, and attributing shell differences to, possibly, a marked genetic mutation. Grimm (1981) considered it to be a distinct species due to external morphological differences (color and shell shape). By 1981, Succinea ovalis could not be found at the Falls; however, during sampling for Hoagland’s electrophoretic
analyses, Succinea ovalis was found at two locations within approximately 16 kilometers of Chittenango Falls. Individuals assigned to Novisuccinea chittenangoensis appeared to be divided into two color morphs, a "gray morph" that was relatively common and widespread at the Falls, and a "red morph" that was restricted to the ledges at the base of the Falls. A preliminary analysis by Hoagland (1984) stated unequivocally that the red and the gray morphs were two distinct species, possibly in separate genera. Solem examined specimens of the gray morph and assigned it to Succinea putris
, an introduced snail possibly from Europe which appears to crowd out all other species.
Hoagland and Davis (1987) subsequently completed a thorough analysis, based on electrophoresis, shell morphology, and internal anatomy, of the succineids at Chittenango Falls. They divided Succinea into two genera, keeping the Old World
Succinea in the genus and elevating the New World
Succinea, of the Section Novisuccinea including ovalis and chittenangoensis, to the genus level. They also determined that the Old World Succinea putris is probably a species complex and that the gray morph, although closely related to Succinea putris sensu lato, is a distinct species, which they designated Succinea sp. B. Based on these factors, the species designation
Novisuccinea chittenangoensis is considered valid. Both species have been observed with red and gray morphs, bringing into question whether the earlier separation truly represented taxonomic distinctiveness. Currently, Novisuccinea chittenangoensis, Succinea sp. B, and 3–4 Oxyloma
spp. are considered to be the only succineid species present at Chittenango Falls. In 2003, the U.S. Geological Survey (T. King, unpublished data) amplified and sequenced the cytochrome oxidase I region
of mitochondrial DNA
and the ITS-1 region of nuclear DNA
in Novisuccinea chittenangoensis and Succinea sp. B. The results (sequence divergence of 10–15 percent) suggest large differences between the two species. No hybridization was observed.
, between the towns of Cazenovia and Chittenango, in Madison County, New York
. At various times in the past, the species has been thought to have a broader range. To date, although many potentially suitable colony sites have been searched, no colony has been conclusively identified as Novisuccinea chittenangoensis outside of the Chittenango Falls area.
During the summer of 1982, "sub-fossil" shells of what appeared to be Novisuccinea chittenangoensis were found in the banks on the west side of Chittenango Creek near the Falls. Grimm (1981) postulated that Pleistocene deposits of what was originally described as Novisuccinea ovalis pleistocenica (Baker, 1927) are in fact shells of Novisuccinea chittenangoensis, and that this species was widely distributed during the Pleistocene
epoch. Shell specimens have been recorded from Yarmouthian Interglacial
, Sangamonian Stage
, and Peorian Stage deposits in the states of Arkansas
, Illinois
, Iowa
, Michigan
, Missouri
, and Nebraska
, and in Ontario
. Alan Solem, however, questioned the assignment of the fossil succineid shell deposits to any species group. Although Hubricht (1985) mapped the location of extant populations of Novisuccinea chittenangoensis to include New York
, West Virginia
, Virginia
, Tennessee
, and North Carolina
, with fossil records from Iowa, Illinois, Missouri, and Arkansas, Hoagland and Davis (1987) concluded that there is only one verified extant population of Novisuccinea chittenangoensis and that it is impossible to verify fossil records as being Novisuccinea chittenangoensis based on shell characteristics alone.
of Novisuccinea chittenangoensis is ovate, slender, acute, and of moderate thickness. The shell suture is deep. The spire
is gently convex, laterally compressed, with 3¼ whorls
. The spire is long, slightly less than half the shell length, and the aperture
is very oblique. The shell color is subtranslucent, calcareous pale yellow to white. The surface is somewhat glossy and marked with growth wrinkles and lines. The size varies somewhat, but adult specimens of the type lot averaged 20.9 millimeters (mm) in shell length. Various adult specimens measured during the summer of 1981 and 1982 ranged from 19 to 24 mm.
Hatchlings measure 1 to 2 mm in shell length, and yearlings average around 10 mm. Measurements of all Novisuccinea chittenangoensis in 2002 ranged from 7 to 23 mm.
The base color of the living animal is very pale subtranslucent yellow. The mantle, kidney, and hepatopancreas
are visible through the shell but are often slightly obscured by the thickness of the shell. The dorsal surface of the mantle
is pale yellow, tinted with olive, often marked with black streaks and blotches. Over the hepatopancreas is a golden yellow tessellation that is marked with gray or black spots and streaks. A dark marking on the posterior surface of the foot is distinctive. However, the mark is not present on the hatchlings, making them impossible to identify in the field. The mark becomes obvious once the snail reaches approximately 6 to 9 mm in length.
(ESF) since 1981 have contributed to the base of knowledge about the biology and life history of Novisuccinea chittenangoensis. Aloi (1985) analyzed the population dynamics
of the succineid snails at Chittenango Falls. Thomee (1986) investigated their behavioral ecology
, and Molloy and Norton (1993) developed techniques for captive propagation
. Molloy (1995) reported on the captive population of Novisuccinea chittenangoensis and associated field studies related to factors influencing the distribution of Succinea sp. B. Confusion on snail identification may have affected the results of Thomee's and Aloi's work, but by the time Molloy's study was initiated, the identification problems had been resolved.
Novisuccinea chittenangoensis survives in and presumably prefers cool, partially sunlit areas of lush herbaceous growth within the spray zone of the Falls.
The habitat of Novisuccinea chittenangoensis lies within the ravine
at the base of the 167-foot-tall waterfall
formed by Chittenango Creek
as it flows north from Cazenovia Lake
toward Oneida Lake
. This north-south oriented ravine forms a deep gorge that is shaded or partially shaded throughout most of the growing season, resulting in a microclimate
that stays relatively cool during the summer, and because of the creek flow and ice formations, is relatively warm in the winter compared to the surrounding area. Spring thaws and periodic major rainfall events tend to remove vegetation from significant portions of the primary Novisuccinea chittenangoensis habitat.
Pilsbry (1948) reported that Novisuccinea chittenangoensis was found "on a sloping weedy talus near the foot of the falls." The only sloping weedy talus is on the east side of the Falls. This area is adjacent to and between the vegetated ledge at the base of the Falls where Novisuccinea chittenangoensis now occurs and the spring-fed watercress beds previously reported to be Novisuccinea chittenangoensis habitat. Presence of Novisuccinea chittenangoensis has not been verified on the west side of the Falls.
Thomee (1986) mapped the habitat occupied by Novisuccinea chittenangoensis. The snails occupied an area of 53.7 m² at the base of the Falls, with most snails found in an area of 11.4 m². More intense studies from 2002 to 2004 have further defined the occupied habitat. Novisuccinea chittenangoensis is found on a ledge beginning at 4 m from the eastern edge of the Falls and extending to 16 m from the Falls. In addition, Novisuccinea chittenangoensis can be found on the middle ledge 4 m above the primary ledge and in the talus as far as 3 m downslope from the primary ledge.
, substrate
, temperature
, vegetation
, and water quality
.
Humidity: Novisuccinea chittenangoensis appears to require sustained, very high humidity. Active snails were found only when relative humidity approached 100 percent; during dry periods, snails were found to be relatively inactive. Portions of the habitat and substrate are consistently at near maximum humidity or saturation in the spray zone of the Falls. However, during 2002, the majority of Novisuccinea chittenangoensis were found >5 m from the edge of the ledge nearest the Falls. Recent monitoring (prior to 2006) with temperature and humidity data loggers shows that these snails occur in an area where the humidity generally varies from 80 to 100 percent during the active season. Further investigation is needed into seasonal and annual hydrological conditions within the Chittenango Creek watershed and at the Falls relative to the high-humidity areas used by Novisuccinea chittenangoensis.
Substrate: Novisuccinea chittenangoensis appears to be a calciphile, requiring a substrate either derived from limestone dolomite
or rich in calcium carbonate
from other sources. The dynamic nature of its habitat does not allow for development of soil.
Temperature: The species appears to require the cool, mild temperatures and relatively constant conditions provided by the waterfalls and the mist
they generate. Water volume and flow rates within the Chittenango Creek watershed influence the size of the waterfall as well as the mist-zone and the actual temperature at the site. Active Novisuccinea chittenangoensis are generally found at temperatures from 12 to 20 °C. During warmer periods, snails retreat to cool areas provided by the moist rock and moss, or aestivate in the vegetation. During cold winter temperatures, it is believed that the snails at the Falls retreat into cracks or fissures in the rocks and remain inactive. Various temperature readings were gathered during the summers of 1980-1982. In the spray zone, the rock surface temperatures averaged 16 °C, the moss averaged 14 °C, and the combined temperatures of the substrate, water, and vegetation averaged 16 °C. Seasonal and daily temperature variation has been monitored for 2 years using data loggers that record temperature every hour, but this data has not yet been analyzed (Breisch, unpublished data).
Vegetation: Most of the spray zone adjacent to the Falls is covered with patches of various mosses, liverworts, and other low herbaceous vegetation, including Eutrochium purpureum, Angelica atropurpurea
, and Aster spp. In addition, watercress Nasturtium officinale increased after the 1993 flood event. Novisuccinea chittenangoensis were found on vegetation up to 92 cm above the ground and at 1/3 the maximum sunlight intensities of the sympatric Succinea sp. B. Vegetation is quite sparse on the west side of the Falls, and the only snails that have been observed there are Succinea sp. B. In drier talus adjacent to the mossy areas are various plant species, such as Eastern skunk cabbage Symplocarpus foetidus and Angelica atropurpurea, upon which Succinea sp. B has also been found. During periods of heavy water flow, dew, or rain, when the vegetation is saturated, the snails have been observed actively crawling on the vegetation. During drier times, both species of snails attach themselves to the underside of leaves with a mucous epiphragm
. In the patch of watercress, the vegetation is dense and lush. Although the watercress is dominant, other species include Angelica atropurpurea, jewelweed Impatiens capensis
and Impatiens pallida
, forget-me-nots Myosotis scorpioides
, various mints Mentha
spp., and poison ivy Toxicodendron radicans, which again support Succinea sp. B but not Novisuccinea chittenangoensis. The ledges where Novisuccinea chittenangoensis is found clearly comprise an early successional
sere, periodically rejuvenated to a bare rock substrate by flood waters.
Water quality: It may be fair to presume that clean water is necessary to maintain essential habitat and a healthy population of Novisuccinea chittenangoensis, just as it is to the survival of many other invertebrates; however, since Novisuccinea chittenangoensis is a terrestrial snail, the effects of water quality are expected to be somewhat indirect. While water quality may play a potential role in the success or decline of Novisuccinea chittenangoensis, this relationship has not been clearly defined to date.
from June through July. They are hermaphroditic; however, it is unclear if self-fertilization is possible. The eggs, numbering 8 to 14, are approximately 2 mm in diameter, spherical, transparent, and very distinctive within a cluster. Generally, Novisuccinea chittenangoensis eggs are not found to have a heavy gelatinous layer surrounding the entire cluster, which is associated with egg masses of Succinea sp. B. Novisuccinea chittenangoensis egg clusters are deposited at the base of plants, under matted vegetation, or in loose, wet soil. The young snails hatch in 2 to 3 weeks, measuring barely 2 mm. It is still unclear when the snails mature, although Grimm (1981) believes they reach maturity in five to eight months, or the spring following hatching. At the end of their first full year of growth, snails observed by Aloi and Ringler (1982) averaged around 10 mm. By the end of the following year, the adult snails were observed to reach a length of approximately 21 mm; they then die, completing a life span of about 2.5 years. This life span is similar to those in captive populations (Rosamond Gifford Zoo
, unpublished data).
from their environment for proper shell formation. Novisuccinea chittenangoensis were generally found on green vegetation, whereas Succinea sp. B was more frequently found on dead vegetation.
Predators may include beetles and sciomyzid
fly larvae, many of which specialize in feeding upon snails. Other potential predators may include the northern two-lined salamander
(Eurycea bislineata), northern dusky salamander
(Desmognathus fuscus), and Allegheny Mountain dusky salamander
(Desmognathus ochrophaeus), which are common in the talus
and on the ledges, as well as various small mammals or passerine
birds such as robins
and pigeons, which are often seen in or near the habitat. Although predation does not appear to be a limiting factor
at this time, its potential impact on a low or stressed population is unclear. The 1978 listing rule included predation by the introduced European snails, Discus rotundatus
and Oxychilus
spp. as serious threats to Novisuccinea chittenangoensis. Little is currently known about this relationship.
for food, breeding or wintering habitat. Hubricht (1985) reported that Succinea putris (Succinea sp. B of Hoagland and Davis) is a "very common species within its range. I found no other Succineidae with it. It appears to crowd out all other species." It does not appear that the other sympatric snail species (e.g., Oxyloma spp.) occurring at the Falls are having a significant impact on Novisuccinea chittenangoensis, as they are thought to be native species. There are no reports of disease or parasites threatening Novisuccinea chittenangoensis.
Endangered Species Unit (beginning in 1976) generally uncovered only a few shells or living animals during annual trips, although an intensive search in July 1981, with Grimm's assistance, yielded 18 live individuals.
Past surveys are suspect, as Grimm (1981) and Hubricht (1985) no longer believe that Novisuccinea ovalis even occurs in Novisuccinea chittenangoensis habitat at Chittenango Falls. They surmise, rather, that earlier reported specimens of Novisuccinea ovalis were instead immature Novisuccinea chittenangoensis. However, a review of photographic records showed shells of Novisuccinea ovalis that were collected at the Falls when the type specimens of Novisuccinea chittenangoensis were collected. Apparently, Novisuccinea ovalis occurred at or near the Falls historically but is no longer encountered there or is only located in adjacent habitats. Therefore, relative comparisons between the two species' abundance is problematic and confusing.
During the summer of 1982, Aloi and Ringler conducted a mark and recapture
study in the patch of watercress where the snails appeared most densely. Using two methods (Jolly and Schnabel) and two models, they estimated a population of about 300 snails with a density of four snails per square meter of watercress habitat. These snails have subsequently been identified as Succinea sp. B, not Novisuccinea chittenangoensis. A 1983 collection of 83 snails for use in electrophoretic studies resulted in removal of 24 Novisuccinea chittenangoensis from the population; unfortunately, their identity was not verified at the time of collection, on top of which Novisuccinea chittenangoensis was thought to be more abundant than it actually was. The population of Succinea sp. B expanded rapidly to an estimate of more than 3,000 snails in 1984, whereas counts of Novisuccinea chittenangoensis in 1984 indicated the presence of approximately 100 adults. Counts of live Novisuccinea chittenangoensis from 1995 to 2001 yielded an average of five adults per survey with a high of 12 adults in 2001. and post-reproductive shell counts made at the end of each activity season from 1987 to 2001 generally identified 4 to 20 Novisuccinea chittenangoensis adults. Subsequent studies have shown that Succinea sp. B outnumbers Novisuccinea chittenangoensis by as much as 10 to 1 in the primary habitat areas.
In 2002, the NYSDEC, ESF
, and the USFWS increased the survey effort and conducted a mark-release-recapture study at the Falls. Sixteen surveys were conducted during the study period between July and October 2002. The final population estimate using the Schumacher-Eschmeyer method
was 183 individuals (95 percent C.I.: 145–222 individuals). Population size was also estimated on the basis of capture frequencies, with a final estimate of 206 individuals. Due to differences in survey intensity and questionable species identifications in years past, the validity and comparability of survey data over the 20-year period do not provide a sound basis for any accurate status statement. The protocol for the mark-release-recapture study was modified slightly and continued in 2003, 2004, and 2005. The Novisuccinea chittenangoensis population was estimated to be 178 in 2003 and 680 in 2004. Preliminary 2005 survey results show a population slightly larger than the 2004 estimate.
In addition to the wild population at Chittenango Falls State Park, efforts to establish captive populations began in 1990. A captive Novisuccinea chittenangoensis colony was being maintained at the Rosamond Gifford Zoo
in Syracuse, New York
, however, the last remaining snails died in November 2002. Other unsuccessful breeding programs were tried in 1990: at ESF at Syracuse; at the Wildlife Conservation Park/Bronx Zoo
; at the Burnet Park Zoo in Syracuse; at the Seneca Park Zoo
(Rochester, New York); and at the Buffalo Zoo
. Further experiments are necessary in order to determine what the proper conditions are for maintaining a healthy captive population of Novisuccinea chittenangoensis.
(43 FR 28932-28935) because of the presumed existence of a second colony in Tennessee
and North Carolina
. After listing, it was determined that the Tennessee/North Carolina snails were not Novisuccinea chittenangoensis, and the Chittenango Falls colony remains the only known population of this species. In 1977, the New York State Department of Environmental Conservation
(NYSDEC) amended the "List of Endangered, Threatened and Special Concern Fish & Wildlife Species of New York State" to include Novisuccinea chittenangoensis as an endangered species in New York.
Approximately 57,000 visitors come to the Park each year for a variety of outdoor recreational activities. The 1978 final rule listing Novisuccinea chittenangoensis as threatened estimated that 60 percent of the habitat at Chittenango Falls was trampled by humans. Human disturbance also continues to threaten Novisuccinea chittenangoensis, although this has been greatly minimized by fencing
of the snail's habitat area at Chittenango Falls. The current strategy for recovering Novisuccinea chittenangoensis includes buffering the species against extinction by perpetuating the extant population at Chittenango Falls at a baseline size, and new attempts in maintaining multiple captive populations.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of small air-breathing land snail
Land snail
A land snail is any of the many species of snail that live on land, as opposed to those that live in salt water and fresh water. Land snails are terrestrial gastropod mollusks that have shells, It is not always an easy matter to say which species are terrestrial, because some are more or less...
in the family Succineidae
Succineidae
Succineidae are a family of small to medium-sized, air-breathing, land snails , terrestrial pulmonate gastropod molluscs. They are commonly called amber snails because their thin fragile shells are translucent and amber-colored...
, the amber snails. This species was discovered in 1905, and was reported three years later as a subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of the oval ambersnail, Succinea ovalis. Several taxonomic
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
reviews took place in the subsequent decades until the end of the 1980s, when the Chittenango ovate amber snail was finally judged to be a distinct species Novisuccinea chittenangoensis, based on chemical and morphological data.
The Chittenango ovate amber snail is endemic to the Chittenango area of Madison County, New York
Madison County, New York
Madison County is a county located in the U.S. state of New York. As of the 2010 census, the population was 73,442. It is named after James Madison, fourth President of the United States of America...
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. There is only one population of this species at Chittenango Falls State Park
Chittenango Falls State Park
Chittenango Falls State Park is located in Madison County, New York east of Cazenovia Lake. The 167 foot waterfall cascades over roughly 400 million year old bedrock, flowing beneath a wooden bridge spanning the meandering Chittenango Creek. The park offers a variety of activities:The park offers...
in central New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...
, even though it was believed to have a broader range previously; based on fossil records, some authors argue that the distribution of this species may have been much wider in the past. In opposition to this, other authors argue that it is impossible to identify this species based on fossil records, because they only allow for examination of shell features. Shell features of species in this particular family of snails are usually not very distinctive.
Novisuccinea chittenangoensis has a small (an average of 20.9 mm in length in adult individuals), delicate, ovate shell of 3¼ whorls
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...
, with deep sutures. The shell is almost translucent, and varies in color from a chalky pale yellow to white, with a glossy surface. Several internal organs of the animal can be distinguished through the shell's outer surface. The visible soft parts of the animal are of a pale subtranslucent yellow color, with different markings during distinct stages of development.
Studies on the ecology
Ecology
Ecology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount , number, and changing states of organisms within and among ecosystems...
of the Chittenango ovate amber snail are fairly recent. It is an herbivorous species which lives in the fresh spray zone of the Chittenango Falls, in partially sunlit areas with lush herbaceous growth. Several parameters appear to be influential in its habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
selection, namely humidity
Humidity
Humidity is a term for the amount of water vapor in the air, and can refer to any one of several measurements of humidity. Formally, humid air is not "moist air" but a mixture of water vapor and other constituents of air, and humidity is defined in terms of the water content of this mixture,...
, substrate
Substrate (biology)
In biology a substrate is the surface a plant or animal lives upon and grows on. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock can be substrate for another animal that lives on top of the algae. See also substrate .-External...
, temperature, vegetation, and water quality. Novisuccinea chittenangoensis is a hermaphroditic species, and its mating
Mating
In biology, mating is the pairing of opposite-sex or hermaphroditic organisms for copulation. In social animals, it also includes the raising of their offspring. Copulation is the union of the sex organs of two sexually reproducing animals for insemination and subsequent internal fertilization...
season is from May through July. It lays egg clusters, each one containing an average of 8 to 14 eggs, at the base of plants, under matted vegetation, or in loose, wet soil. Maturity
Sexual maturity
Sexual maturity is the age or stage when an organism can reproduce. It is sometimes considered synonymous with adulthood, though the two are distinct...
is reached in five to eight months, and its life span is roughly 2.5 years. Some of its predators include insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s, amphibian
Amphibian
Amphibians , are a class of vertebrate animals including animals such as toads, frogs, caecilians, and salamanders. They are characterized as non-amniote ectothermic tetrapods...
s, mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s, bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s, and occasionally other snails.
Since the time of its discovery in 1905, there have been many attempts to estimate the population
Population
A population is all the organisms that both belong to the same group or species and live in the same geographical area. The area that is used to define a sexual population is such that inter-breeding is possible between any pair within the area and more probable than cross-breeding with individuals...
size of this species. Results varied greatly, but the more recent ones suggest a very reduced number of individuals. This coupled with a very restricted distribution
Range (biology)
In biology, the range or distribution of a species is the geographical area within which that species can be found. Within that range, dispersion is variation in local density.The term is often qualified:...
have led to the listing of Novisuccinea chittenangoensis as an endangered
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
or threatened
Threatened species
Threatened species are any speciesg animals, plants, fungi, etc.) which are vulnerable to endangerment in the near future.The World Conservation Union is the foremost authority on threatened species, and treats threatened species not as a single category, but as a group of three categories,...
species. Humans frequently invade its habitat, though such disturbances have been greatly reduced by preventive measures. Recent efforts in conservation include perpetuating the extant population at a baseline size as well as maintaining captive populations.
Taxonomy
The snail was first discovered at Chittenango Falls in August 1905 by a field party from the Academy of Natural SciencesAcademy of Natural Sciences
The Academy of Natural Sciences of Drexel University, formerly Academy of Natural Sciences of Philadelphia, is the oldest natural science research institution and museum in the New World...
of Philadelphia. In 1908, Henry Augustus Pilsbry
Henry Augustus Pilsbry
Henry Augustus Pilsbry was an American biologist, malacologist and carcinologist, among other areas of study. He was a dominant presence in many fields of invertebrate taxonomy for the better part of a century...
reported the discovery, describing the snail as a subspecies of the widely distributed Succinea ovalis. Because of this, the Chittenango ovate amber snail is referred to in many publications as Succinea ovalis chittenangoensis.
Pilsbry placed Succinea ovalis in the subgenus
Subgenus
In biology, a subgenus is a taxonomic rank directly below genus.In zoology, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the generic name and the specific epithet: e.g. the Tiger Cowry of the Indo-Pacific, Cypraea tigris Linnaeus, which...
Novisuccinea
Novisuccinea
Novisuccinea is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Succineidae, the ambersnails.- Species :Species in the genus Novisuccinea include:* Novisuccinea ovalis - oval ambersnail...
in 1948. Alan Solem
Alan Solem
Alan Solem, full name George Alan Solem was an American malacologist, a biologist who studied mollusks.He was one of the most renown land snail experts of his time and had earned a reputation for his comprehensive revisions of mainly terrestrial pulmonates...
(1976) considered this snail to be merely a form of Succinea ovalis, citing similarities in genitalia and radula
Radula
The radula is an anatomical structure that is used by molluscs for feeding, sometimes compared rather inaccurately to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus...
, and attributing shell differences to, possibly, a marked genetic mutation. Grimm (1981) considered it to be a distinct species due to external morphological differences (color and shell shape). By 1981, Succinea ovalis could not be found at the Falls; however, during sampling for Hoagland’s electrophoretic
Electrophoresis
Electrophoresis, also called cataphoresis, is the motion of dispersed particles relative to a fluid under the influence of a spatially uniform electric field. This electrokinetic phenomenon was observed for the first time in 1807 by Reuss , who noticed that the application of a constant electric...
analyses, Succinea ovalis was found at two locations within approximately 16 kilometers of Chittenango Falls. Individuals assigned to Novisuccinea chittenangoensis appeared to be divided into two color morphs, a "gray morph" that was relatively common and widespread at the Falls, and a "red morph" that was restricted to the ledges at the base of the Falls. A preliminary analysis by Hoagland (1984) stated unequivocally that the red and the gray morphs were two distinct species, possibly in separate genera. Solem examined specimens of the gray morph and assigned it to Succinea putris
Succinea putris
Succinea putris is a species of small, air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Succineidae, the amber snails.-Distribution:Distribution: European-Siberian region.* Czech Republic - least concern * Germany...
, an introduced snail possibly from Europe which appears to crowd out all other species.
Hoagland and Davis (1987) subsequently completed a thorough analysis, based on electrophoresis, shell morphology, and internal anatomy, of the succineids at Chittenango Falls. They divided Succinea into two genera, keeping the Old World
Old World
The Old World consists of those parts of the world known to classical antiquity and the European Middle Ages. It is used in the context of, and contrast with, the "New World" ....
Succinea in the genus and elevating the New World
New World
The New World is one of the names used for the Western Hemisphere, specifically America and sometimes Oceania . The term originated in the late 15th century, when America had been recently discovered by European explorers, expanding the geographical horizon of the people of the European middle...
Succinea, of the Section Novisuccinea including ovalis and chittenangoensis, to the genus level. They also determined that the Old World Succinea putris is probably a species complex and that the gray morph, although closely related to Succinea putris sensu lato, is a distinct species, which they designated Succinea sp. B. Based on these factors, the species designation
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
Novisuccinea chittenangoensis is considered valid. Both species have been observed with red and gray morphs, bringing into question whether the earlier separation truly represented taxonomic distinctiveness. Currently, Novisuccinea chittenangoensis, Succinea sp. B, and 3–4 Oxyloma
Oxyloma
Oxyloma is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Succineidae, the ambersnails.-Species:The genus Oxyloma includes the following species and subspecies:...
spp. are considered to be the only succineid species present at Chittenango Falls. In 2003, the U.S. Geological Survey (T. King, unpublished data) amplified and sequenced the cytochrome oxidase I region
Main subunit of cytochrome c oxidase
Cytochrome C and Quinol oxidase polypeptide I is main subunit of cytochrome c oxidase complex.Cytochrome c oxidase is a key enzyme in aerobic metabolism. Proton pumping heme-copper oxidases represent the terminal, energy-transfer enzymes of respiratory chains in prokaryotes and eukaryotes...
of mitochondrial DNA
Mitochondrial DNA
Mitochondrial DNA is the DNA located in organelles called mitochondria, structures within eukaryotic cells that convert the chemical energy from food into a form that cells can use, adenosine triphosphate...
and the ITS-1 region of nuclear DNA
Nuclear DNA
Nuclear DNA, nuclear deoxyribonucleic acid , is DNA contained within a nucleus of eukaryotic organisms. In mammals and vertebrates, nuclear DNA encodes more of the genome than the mitochondrial DNA and is composed of information inherited from two parents, one male, and one female, rather than...
in Novisuccinea chittenangoensis and Succinea sp. B. The results (sequence divergence of 10–15 percent) suggest large differences between the two species. No hybridization was observed.
Distribution
The only verified extant colony of Novisuccinea chittenangoensis is the type population, which is at Chittenango Falls, in Chittenango Falls State Park, 3.6 miles north of CazenoviaCazenovia (town), New York
Cazenovia is a town in Madison County, New York, United States. The population was 6,481 at the 2000 census. The town is named after Theophilus Cazenove, an agent of the Holland Land Company.The Town of Cazenovia has a village also named Cazenovia...
, between the towns of Cazenovia and Chittenango, in Madison County, New York
Madison County, New York
Madison County is a county located in the U.S. state of New York. As of the 2010 census, the population was 73,442. It is named after James Madison, fourth President of the United States of America...
. At various times in the past, the species has been thought to have a broader range. To date, although many potentially suitable colony sites have been searched, no colony has been conclusively identified as Novisuccinea chittenangoensis outside of the Chittenango Falls area.
During the summer of 1982, "sub-fossil" shells of what appeared to be Novisuccinea chittenangoensis were found in the banks on the west side of Chittenango Creek near the Falls. Grimm (1981) postulated that Pleistocene deposits of what was originally described as Novisuccinea ovalis pleistocenica (Baker, 1927) are in fact shells of Novisuccinea chittenangoensis, and that this species was widely distributed during the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
epoch. Shell specimens have been recorded from Yarmouthian Interglacial
Yarmouthian Interglacial (Stage)
The Yarmouthian stage and the Yarmouth Interglacial were part of a now obsolete geologic timescale of the early Quaternary of North America.-Development:This climatic and chronological framework was composed of four glacial and interglacial stages...
, Sangamonian Stage
Sangamonian Stage
The Sangamonian Stage, also known as the Sangamon interglacial, is the name used by Quaternary geologists to designate the last interglacial period in North America from 125,000—75,000 years ago, a period of...
, and Peorian Stage deposits in the states of Arkansas
Arkansas
Arkansas is a state located in the southern region of the United States. Its name is an Algonquian name of the Quapaw Indians. Arkansas shares borders with six states , and its eastern border is largely defined by the Mississippi River...
, Illinois
Illinois
Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,...
, Iowa
Iowa
Iowa is a state located in the Midwestern United States, an area often referred to as the "American Heartland". It derives its name from the Ioway people, one of the many American Indian tribes that occupied the state at the time of European exploration. Iowa was a part of the French colony of New...
, Michigan
Michigan
Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake"....
, Missouri
Missouri
Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It...
, and Nebraska
Nebraska
Nebraska is a state on the Great Plains of the Midwestern United States. The state's capital is Lincoln and its largest city is Omaha, on the Missouri River....
, and in Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
. Alan Solem, however, questioned the assignment of the fossil succineid shell deposits to any species group. Although Hubricht (1985) mapped the location of extant populations of Novisuccinea chittenangoensis to include New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...
, West Virginia
West Virginia
West Virginia is a state in the Appalachian and Southeastern regions of the United States, bordered by Virginia to the southeast, Kentucky to the southwest, Ohio to the northwest, Pennsylvania to the northeast and Maryland to the east...
, Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
, Tennessee
Tennessee
Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...
, and North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
, with fossil records from Iowa, Illinois, Missouri, and Arkansas, Hoagland and Davis (1987) concluded that there is only one verified extant population of Novisuccinea chittenangoensis and that it is impossible to verify fossil records as being Novisuccinea chittenangoensis based on shell characteristics alone.
Description
The shellGastropod shell
The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...
of Novisuccinea chittenangoensis is ovate, slender, acute, and of moderate thickness. The shell suture is deep. The spire
Spire (mollusc)
A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...
is gently convex, laterally compressed, with 3¼ whorls
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...
. The spire is long, slightly less than half the shell length, and the aperture
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....
is very oblique. The shell color is subtranslucent, calcareous pale yellow to white. The surface is somewhat glossy and marked with growth wrinkles and lines. The size varies somewhat, but adult specimens of the type lot averaged 20.9 millimeters (mm) in shell length. Various adult specimens measured during the summer of 1981 and 1982 ranged from 19 to 24 mm.
Hatchlings measure 1 to 2 mm in shell length, and yearlings average around 10 mm. Measurements of all Novisuccinea chittenangoensis in 2002 ranged from 7 to 23 mm.
The base color of the living animal is very pale subtranslucent yellow. The mantle, kidney, and hepatopancreas
Hepatopancreas
The hepatopancreas, digestive gland or midgut gland is an organ of the digestive tract of arthropods, molluscs and fish. It provides the functions which in mammals are provided separately by the liver and pancreas, including the production of digestive enzymes, and absorption of digested...
are visible through the shell but are often slightly obscured by the thickness of the shell. The dorsal surface of the mantle
Mantle (mollusc)
The mantle is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.In many, but by no means all, species of molluscs, the epidermis of the mantle secretes...
is pale yellow, tinted with olive, often marked with black streaks and blotches. Over the hepatopancreas is a golden yellow tessellation that is marked with gray or black spots and streaks. A dark marking on the posterior surface of the foot is distinctive. However, the mark is not present on the hatchlings, making them impossible to identify in the field. The mark becomes obvious once the snail reaches approximately 6 to 9 mm in length.
Ecology
Until recently, relatively little was known about the biology of the Chittenango ovate amber snail. Studies by investigators at the State University of New York College of Environmental Science and ForestryState University of New York College of Environmental Science and Forestry
The State University of New York College of Environmental Science and Forestry is an American specialized doctoral-granting institution located in the University Hill neighborhood of Syracuse, New York, immediately adjacent to Syracuse University...
(ESF) since 1981 have contributed to the base of knowledge about the biology and life history of Novisuccinea chittenangoensis. Aloi (1985) analyzed the population dynamics
Population dynamics
Population dynamics is the branch of life sciences that studies short-term and long-term changes in the size and age composition of populations, and the biological and environmental processes influencing those changes...
of the succineid snails at Chittenango Falls. Thomee (1986) investigated their behavioral ecology
Behavioral ecology
Behavioral ecology, or ethoecology, is the study of the ecological and evolutionary basis for animal behavior, and the roles of behavior in enabling an animal to adapt to its environment...
, and Molloy and Norton (1993) developed techniques for captive propagation
Captive breeding
Captive breedingis the process of breeding animals in human controlled environments with restricted settings, such as wildlife reserves, zoos and other conservation facilities; sometimes the process is construed to include release of individual organisms to the wild, when there is sufficient...
. Molloy (1995) reported on the captive population of Novisuccinea chittenangoensis and associated field studies related to factors influencing the distribution of Succinea sp. B. Confusion on snail identification may have affected the results of Thomee's and Aloi's work, but by the time Molloy's study was initiated, the identification problems had been resolved.
Habitat
The habitat of Novisuccinea chittenangoensis lies within the ravine
Ravine
A ravine is a landform narrower than a canyon and is often the product of streamcutting erosion. Ravines are typically classified as larger in scale than gullies, although smaller than valleys. A ravine is generally a fluvial slope landform of relatively steep sides, on the order of twenty to...
at the base of the 167-foot-tall waterfall
Waterfall
A waterfall is a place where flowing water rapidly drops in elevation as it flows over a steep region or a cliff.-Formation:Waterfalls are commonly formed when a river is young. At these times the channel is often narrow and deep. When the river courses over resistant bedrock, erosion happens...
formed by Chittenango Creek
Chittenango Creek
Chittenango Creek is a small river in central New York, USA. Chittenango Creek flows northward through Chittenango into Oneida Lake near the community of Bridgeport and partially forms the boundary between Onondaga County and Madison County...
as it flows north from Cazenovia Lake
Cazenovia Lake
Cazenovia Lake is a lake in New York, United States. It is located 20 miles from Syracuse, New York. Cazenovia, New York is located southeast of the lake. The lake is roughly 4 miles long and 0.5 mile wide...
toward Oneida Lake
Oneida Lake
Oneida Lake is the largest lake entirely within New York State . The lake is located northeast of Syracuse and near the Great Lakes. It serves as one of the links in the Erie Canal. It empties into the Oneida River which flows into the Oswego River which in turn flows into Lake Ontario...
. This north-south oriented ravine forms a deep gorge that is shaded or partially shaded throughout most of the growing season, resulting in a microclimate
Microclimate
A microclimate is a local atmospheric zone where the climate differs from the surrounding area. The term may refer to areas as small as a few square feet or as large as many square miles...
that stays relatively cool during the summer, and because of the creek flow and ice formations, is relatively warm in the winter compared to the surrounding area. Spring thaws and periodic major rainfall events tend to remove vegetation from significant portions of the primary Novisuccinea chittenangoensis habitat.
Pilsbry (1948) reported that Novisuccinea chittenangoensis was found "on a sloping weedy talus near the foot of the falls." The only sloping weedy talus is on the east side of the Falls. This area is adjacent to and between the vegetated ledge at the base of the Falls where Novisuccinea chittenangoensis now occurs and the spring-fed watercress beds previously reported to be Novisuccinea chittenangoensis habitat. Presence of Novisuccinea chittenangoensis has not been verified on the west side of the Falls.
Thomee (1986) mapped the habitat occupied by Novisuccinea chittenangoensis. The snails occupied an area of 53.7 m² at the base of the Falls, with most snails found in an area of 11.4 m². More intense studies from 2002 to 2004 have further defined the occupied habitat. Novisuccinea chittenangoensis is found on a ledge beginning at 4 m from the eastern edge of the Falls and extending to 16 m from the Falls. In addition, Novisuccinea chittenangoensis can be found on the middle ledge 4 m above the primary ledge and in the talus as far as 3 m downslope from the primary ledge.
Habitat parameters
Five parameters appear to have significance in the preferred habitat: humidityHumidity
Humidity is a term for the amount of water vapor in the air, and can refer to any one of several measurements of humidity. Formally, humid air is not "moist air" but a mixture of water vapor and other constituents of air, and humidity is defined in terms of the water content of this mixture,...
, substrate
Substrate (biology)
In biology a substrate is the surface a plant or animal lives upon and grows on. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock can be substrate for another animal that lives on top of the algae. See also substrate .-External...
, temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
, vegetation
Vegetation
Vegetation is a general term for the plant life of a region; it refers to the ground cover provided by plants. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristics. It is broader...
, and water quality
Water quality
Water quality is the physical, chemical and biological characteristics of water. It is a measure of the condition of water relative to the requirements of one or more biotic species and or to any human need or purpose. It is most frequently used by reference to a set of standards against which...
.
Humidity: Novisuccinea chittenangoensis appears to require sustained, very high humidity. Active snails were found only when relative humidity approached 100 percent; during dry periods, snails were found to be relatively inactive. Portions of the habitat and substrate are consistently at near maximum humidity or saturation in the spray zone of the Falls. However, during 2002, the majority of Novisuccinea chittenangoensis were found >5 m from the edge of the ledge nearest the Falls. Recent monitoring (prior to 2006) with temperature and humidity data loggers shows that these snails occur in an area where the humidity generally varies from 80 to 100 percent during the active season. Further investigation is needed into seasonal and annual hydrological conditions within the Chittenango Creek watershed and at the Falls relative to the high-humidity areas used by Novisuccinea chittenangoensis.
Substrate: Novisuccinea chittenangoensis appears to be a calciphile, requiring a substrate either derived from limestone dolomite
Dolomite
Dolomite is a carbonate mineral composed of calcium magnesium carbonate CaMg2. The term is also used to describe the sedimentary carbonate rock dolostone....
or rich in calcium carbonate
Calcium carbonate
Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...
from other sources. The dynamic nature of its habitat does not allow for development of soil.
Temperature: The species appears to require the cool, mild temperatures and relatively constant conditions provided by the waterfalls and the mist
Mist
Mist is a phenomenon of small droplets suspended in air. It can occur as part of natural weather or volcanic activity, and is common in cold air above warmer water, in exhaled air in the cold, and in a steam room of a sauna. It can also be created artificially with aerosol canisters if the...
they generate. Water volume and flow rates within the Chittenango Creek watershed influence the size of the waterfall as well as the mist-zone and the actual temperature at the site. Active Novisuccinea chittenangoensis are generally found at temperatures from 12 to 20 °C. During warmer periods, snails retreat to cool areas provided by the moist rock and moss, or aestivate in the vegetation. During cold winter temperatures, it is believed that the snails at the Falls retreat into cracks or fissures in the rocks and remain inactive. Various temperature readings were gathered during the summers of 1980-1982. In the spray zone, the rock surface temperatures averaged 16 °C, the moss averaged 14 °C, and the combined temperatures of the substrate, water, and vegetation averaged 16 °C. Seasonal and daily temperature variation has been monitored for 2 years using data loggers that record temperature every hour, but this data has not yet been analyzed (Breisch, unpublished data).
Vegetation: Most of the spray zone adjacent to the Falls is covered with patches of various mosses, liverworts, and other low herbaceous vegetation, including Eutrochium purpureum, Angelica atropurpurea
Angelica atropurpurea
Angelica atropurpurea is a species of plant that can be found in moist and swampy woodlands, mostly by riverbanks. The plant grows to 6 feet tall with an erect branching stem that is purple. The stem is smooth, hollow, and sturdy. The leaves are divided into three parts, each with its own petiole....
, and Aster spp. In addition, watercress Nasturtium officinale increased after the 1993 flood event. Novisuccinea chittenangoensis were found on vegetation up to 92 cm above the ground and at 1/3 the maximum sunlight intensities of the sympatric Succinea sp. B. Vegetation is quite sparse on the west side of the Falls, and the only snails that have been observed there are Succinea sp. B. In drier talus adjacent to the mossy areas are various plant species, such as Eastern skunk cabbage Symplocarpus foetidus and Angelica atropurpurea, upon which Succinea sp. B has also been found. During periods of heavy water flow, dew, or rain, when the vegetation is saturated, the snails have been observed actively crawling on the vegetation. During drier times, both species of snails attach themselves to the underside of leaves with a mucous epiphragm
Epiphragm
An epiphragm is a temporary structure which can be created by many species of shelled, air-breathing land snails, terrestrial pulmonate gastropod mollusks. It can also be created by freshwater snails when temporary pools dry up....
. In the patch of watercress, the vegetation is dense and lush. Although the watercress is dominant, other species include Angelica atropurpurea, jewelweed Impatiens capensis
Impatiens capensis
Impatiens capensis, the Orange Jewelweed, Common Jewelweed, Spotted Jewelweed, Spotted Touch-me-not, or Orange Balsam, is an annual plant native to North America. It is common in bottomland soils, ditches, and along creeks, often growing side-by-side with its less common relative, Yellow Jewelweed...
and Impatiens pallida
Impatiens pallida
Pale Jewelweed or Yellow Jewelweed is a flowering plant native to the United States. It grows in moist to wet soils, generally alongside the closely related Impatiens capensis, producing flowers from midsummer through fall...
, forget-me-nots Myosotis scorpioides
Myosotis scorpioides
Myosotis scorpioides , the Water Forget-me-not or True Forget-me-not, is a herbaceous perennial plant of the genus Myosotis. It is native to Europe and Asia and it can be found elsewhere, including much of North America, as an introduced species and sometimes a noxious weed. It grows in bogs and...
, various mints Mentha
Mentha
Mentha is a genus of flowering plants in the family Lamiaceae . The species are not clearly distinct and estimates of the number of species varies from 13 to 18. Hybridization between some of the species occurs naturally...
spp., and poison ivy Toxicodendron radicans, which again support Succinea sp. B but not Novisuccinea chittenangoensis. The ledges where Novisuccinea chittenangoensis is found clearly comprise an early successional
Ecological succession
Ecological succession, is the phenomenon or process by which a community progressively transforms itself until a stable community is formed. It is a fundamental concept in ecology, and refers to more or less predictable and orderly changes in the composition or structure of an ecological community...
sere, periodically rejuvenated to a bare rock substrate by flood waters.
Water quality: It may be fair to presume that clean water is necessary to maintain essential habitat and a healthy population of Novisuccinea chittenangoensis, just as it is to the survival of many other invertebrates; however, since Novisuccinea chittenangoensis is a terrestrial snail, the effects of water quality are expected to be somewhat indirect. While water quality may play a potential role in the success or decline of Novisuccinea chittenangoensis, this relationship has not been clearly defined to date.
Life cycle
The snails mate from May through July, and lay eggsOviposition
Oviposition is the process of laying eggs by oviparous animals.Some arthropods, for example, lay their eggs with an organ called the ovipositor.Fish , amphibians, reptiles, birds and monetremata also lay eggs....
from June through July. They are hermaphroditic; however, it is unclear if self-fertilization is possible. The eggs, numbering 8 to 14, are approximately 2 mm in diameter, spherical, transparent, and very distinctive within a cluster. Generally, Novisuccinea chittenangoensis eggs are not found to have a heavy gelatinous layer surrounding the entire cluster, which is associated with egg masses of Succinea sp. B. Novisuccinea chittenangoensis egg clusters are deposited at the base of plants, under matted vegetation, or in loose, wet soil. The young snails hatch in 2 to 3 weeks, measuring barely 2 mm. It is still unclear when the snails mature, although Grimm (1981) believes they reach maturity in five to eight months, or the spring following hatching. At the end of their first full year of growth, snails observed by Aloi and Ringler (1982) averaged around 10 mm. By the end of the following year, the adult snails were observed to reach a length of approximately 21 mm; they then die, completing a life span of about 2.5 years. This life span is similar to those in captive populations (Rosamond Gifford Zoo
Rosamond Gifford Zoo
The Rosamond Gifford Zoo at Burnet Park is a zoo in Syracuse, New York. It is owned and operated by Onondaga County Parks. The zoo is home to more than 900 animals on . Some of the more popular animals include Asian elephants, Humboldt penguins, Amur tigers and African lions...
, unpublished data).
Feeding habits
Novisuccinea chittenangoensis apparently feed on microflora and must obtain high levels of calcium carbonateCalcium carbonate
Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...
from their environment for proper shell formation. Novisuccinea chittenangoensis were generally found on green vegetation, whereas Succinea sp. B was more frequently found on dead vegetation.
Predators
Sciomyzidae
The family Sciomyzidae belongs to the typical flies of the order Diptera. They are commonly called marsh flies, and in some cases snail-killing flies due to the food of their larvae....
fly larvae, many of which specialize in feeding upon snails. Other potential predators may include the northern two-lined salamander
Northern Two-lined Salamander
The Northern two-lined salamander is a species of salamander in the Plethodontidae family.It is found in Canada and the United States....
(Eurycea bislineata), northern dusky salamander
Dusky Salamander
The Dusky Salamander is an amphibian in the lungless salamander family. The species is also sometimes called the Northern Dusky Salamander by those acknowledging that populations in the southern United States form a separate species, called the Southern Dusky Salamander...
(Desmognathus fuscus), and Allegheny Mountain dusky salamander
Allegheny Mountain Dusky Salamander
The Allegheny Mountain dusky salamander is a species in the Plethodontidae family.It is found in Canada and the United States....
(Desmognathus ochrophaeus), which are common in the talus
Scree
Scree, also called talus, is a term given to an accumulation of broken rock fragments at the base of crags, mountain cliffs, or valley shoulders. Landforms associated with these materials are sometimes called scree slopes or talus piles...
and on the ledges, as well as various small mammals or passerine
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
birds such as robins
American Robin
The American Robin or North American Robin is a migratory songbird of the thrush family. It is named after the European Robin because of its reddish-orange breast, though the two species are not closely related, with the European robin belonging to the flycatcher family...
and pigeons, which are often seen in or near the habitat. Although predation does not appear to be a limiting factor
Limiting factor
A limiting factor or limiting resource is a factor that controls a process, such as organism growth or species population, size, or distribution. The availability of food, predation pressure, or availability of shelter are examples of factors that could be limiting for an organism...
at this time, its potential impact on a low or stressed population is unclear. The 1978 listing rule included predation by the introduced European snails, Discus rotundatus
Discus rotundatus
Discus rotundatus is a species of small, air-breathing, land snail, a terrestrial pulmonate gastropod mollusk in the family Discidae, the disk snails.-Distribution:...
and Oxychilus
Oxychilus
Oxychilus is a genus of small air-breathing land snails, terrestrial pulmonate gastropods in the family Oxychilidae, the glass snails.-Species:There are more than 100 species in the genus Oxychilus...
spp. as serious threats to Novisuccinea chittenangoensis. Little is currently known about this relationship.
Interspecific relationships
Interactions with Succinea sp. B may be having a significant impact on Novisuccinea chittenangoensis, as both species may be competingCompetition (biology)
Competition is an interaction between organisms or species, in which the fitness of one is lowered by the presence of another. Limited supply of at least one resource used by both is required. Competition both within and between species is an important topic in ecology, especially community ecology...
for food, breeding or wintering habitat. Hubricht (1985) reported that Succinea putris (Succinea sp. B of Hoagland and Davis) is a "very common species within its range. I found no other Succineidae with it. It appears to crowd out all other species." It does not appear that the other sympatric snail species (e.g., Oxyloma spp.) occurring at the Falls are having a significant impact on Novisuccinea chittenangoensis, as they are thought to be native species. There are no reports of disease or parasites threatening Novisuccinea chittenangoensis.
Population size
Accurate population trends are not available for this species. The species was supposedly found "in great abundance" when a field party collected it in 1905, but was not surveyed again until 1954, when Hubricht found it in "equal abundance" with Novisuccinea ovalis. Grimm found Novisuccinea ovalis more abundant than Novisuccinea chittenangoensis during field surveys in 1964, 1965, and 1973. In 1972, Grimm estimated the total Novisuccinea chittenangoensis population at less than 200, but Solem estimated it at about 500 in 1974. Three investigators spent two hours searching the habitat in 1973 and located only 13 specimens; a trip later that summer yielded none. Surveys by the New York State Department of Environmental ConservationNew York State Department of Environmental Conservation
The New York State Department of Environmental Conservation is responsible for the conservation, improvement, and protection of natural resources within the U.S. state of New York. It was founded in 1970, replacing the previous Conservation Department...
Endangered Species Unit (beginning in 1976) generally uncovered only a few shells or living animals during annual trips, although an intensive search in July 1981, with Grimm's assistance, yielded 18 live individuals.
Past surveys are suspect, as Grimm (1981) and Hubricht (1985) no longer believe that Novisuccinea ovalis even occurs in Novisuccinea chittenangoensis habitat at Chittenango Falls. They surmise, rather, that earlier reported specimens of Novisuccinea ovalis were instead immature Novisuccinea chittenangoensis. However, a review of photographic records showed shells of Novisuccinea ovalis that were collected at the Falls when the type specimens of Novisuccinea chittenangoensis were collected. Apparently, Novisuccinea ovalis occurred at or near the Falls historically but is no longer encountered there or is only located in adjacent habitats. Therefore, relative comparisons between the two species' abundance is problematic and confusing.
During the summer of 1982, Aloi and Ringler conducted a mark and recapture
Mark and recapture
Mark and recapture is a method commonly used in ecology to estimate population size. This method is most valuable when a researcher fails to detect all individuals present within a population of interest every time that researcher visits the study area...
study in the patch of watercress where the snails appeared most densely. Using two methods (Jolly and Schnabel) and two models, they estimated a population of about 300 snails with a density of four snails per square meter of watercress habitat. These snails have subsequently been identified as Succinea sp. B, not Novisuccinea chittenangoensis. A 1983 collection of 83 snails for use in electrophoretic studies resulted in removal of 24 Novisuccinea chittenangoensis from the population; unfortunately, their identity was not verified at the time of collection, on top of which Novisuccinea chittenangoensis was thought to be more abundant than it actually was. The population of Succinea sp. B expanded rapidly to an estimate of more than 3,000 snails in 1984, whereas counts of Novisuccinea chittenangoensis in 1984 indicated the presence of approximately 100 adults. Counts of live Novisuccinea chittenangoensis from 1995 to 2001 yielded an average of five adults per survey with a high of 12 adults in 2001. and post-reproductive shell counts made at the end of each activity season from 1987 to 2001 generally identified 4 to 20 Novisuccinea chittenangoensis adults. Subsequent studies have shown that Succinea sp. B outnumbers Novisuccinea chittenangoensis by as much as 10 to 1 in the primary habitat areas.
In 2002, the NYSDEC, ESF
State University of New York College of Environmental Science and Forestry
The State University of New York College of Environmental Science and Forestry is an American specialized doctoral-granting institution located in the University Hill neighborhood of Syracuse, New York, immediately adjacent to Syracuse University...
, and the USFWS increased the survey effort and conducted a mark-release-recapture study at the Falls. Sixteen surveys were conducted during the study period between July and October 2002. The final population estimate using the Schumacher-Eschmeyer method
was 183 individuals (95 percent C.I.: 145–222 individuals). Population size was also estimated on the basis of capture frequencies, with a final estimate of 206 individuals. Due to differences in survey intensity and questionable species identifications in years past, the validity and comparability of survey data over the 20-year period do not provide a sound basis for any accurate status statement. The protocol for the mark-release-recapture study was modified slightly and continued in 2003, 2004, and 2005. The Novisuccinea chittenangoensis population was estimated to be 178 in 2003 and 680 in 2004. Preliminary 2005 survey results show a population slightly larger than the 2004 estimate.
In addition to the wild population at Chittenango Falls State Park, efforts to establish captive populations began in 1990. A captive Novisuccinea chittenangoensis colony was being maintained at the Rosamond Gifford Zoo
Rosamond Gifford Zoo
The Rosamond Gifford Zoo at Burnet Park is a zoo in Syracuse, New York. It is owned and operated by Onondaga County Parks. The zoo is home to more than 900 animals on . Some of the more popular animals include Asian elephants, Humboldt penguins, Amur tigers and African lions...
in Syracuse, New York
Syracuse, New York
Syracuse is a city in and the county seat of Onondaga County, New York, United States, the largest U.S. city with the name "Syracuse", and the fifth most populous city in the state. At the 2010 census, the city population was 145,170, and its metropolitan area had a population of 742,603...
, however, the last remaining snails died in November 2002. Other unsuccessful breeding programs were tried in 1990: at ESF at Syracuse; at the Wildlife Conservation Park/Bronx Zoo
Bronx Zoo
The Bronx Zoo is located in the Bronx borough of New York City, within Bronx Park. It is the largest metropolitan zoo in the United States, comprising of park lands and naturalistic habitats, through which the Bronx River flows....
; at the Burnet Park Zoo in Syracuse; at the Seneca Park Zoo
Seneca Park Zoo
Seneca Park Zoo is a zoo located in Rochester, New York. The Zoo is home to about 300 animals, and is accredited by the Association of Zoos and Aquariums . The zoo is run by Monroe County, New York and supported by the Seneca Park Zoo Society. Larry Sorel is the Director of the Zoo and Rachel...
(Rochester, New York); and at the Buffalo Zoo
Buffalo Zoo
Founded in 1875, the Buffalo Zoo located in Buffalo, New York is the third oldest zoo in the United States. Each year, the Buffalo Zoo welcomes approximately 400,000 visitors and is the second largest tourist attraction in Western New York, second only to Niagara Falls...
. Further experiments are necessary in order to determine what the proper conditions are for maintaining a healthy captive population of Novisuccinea chittenangoensis.
Conservation
Novisuccinea chittenangoensis was originally proposed as a Federal endangered species in April 1976 (41 FR 17742-17747), owing to an apparent decline in the species’ population coupled with its extremely limited range. Ultimately, however, the species was listed as threatened in July 1978(43 FR 28932-28935) because of the presumed existence of a second colony in Tennessee
Tennessee
Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...
and North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
. After listing, it was determined that the Tennessee/North Carolina snails were not Novisuccinea chittenangoensis, and the Chittenango Falls colony remains the only known population of this species. In 1977, the New York State Department of Environmental Conservation
New York State Department of Environmental Conservation
The New York State Department of Environmental Conservation is responsible for the conservation, improvement, and protection of natural resources within the U.S. state of New York. It was founded in 1970, replacing the previous Conservation Department...
(NYSDEC) amended the "List of Endangered, Threatened and Special Concern Fish & Wildlife Species of New York State" to include Novisuccinea chittenangoensis as an endangered species in New York.
Approximately 57,000 visitors come to the Park each year for a variety of outdoor recreational activities. The 1978 final rule listing Novisuccinea chittenangoensis as threatened estimated that 60 percent of the habitat at Chittenango Falls was trampled by humans. Human disturbance also continues to threaten Novisuccinea chittenangoensis, although this has been greatly minimized by fencing
Fence
A fence is a freestanding structure designed to restrict or prevent movement across a boundary. It is generally distinguished from a wall by the lightness of its construction: a wall is usually restricted to such barriers made from solid brick or concrete, blocking vision as well as passage .Fences...
of the snail's habitat area at Chittenango Falls. The current strategy for recovering Novisuccinea chittenangoensis includes buffering the species against extinction by perpetuating the extant population at Chittenango Falls at a baseline size, and new attempts in maintaining multiple captive populations.
External links
- Species Profile of Chittenango Ovate Amber snail (Succinea chittenangoensis) at U.S. Fish and Wildlife Service website
- New York State Department of Environmental ConservationNew York State Department of Environmental ConservationThe New York State Department of Environmental Conservation is responsible for the conservation, improvement, and protection of natural resources within the U.S. state of New York. It was founded in 1970, replacing the previous Conservation Department...
; Snail Fact Sheet Novisuccinea chittenangoensis. - Drawing of genitalia of Novisuccinea chittenangoensis by Solem (1976) at Figure 1, images g and h.
- Photo of radula of Novisuccinea chittenangoensis by Solem (1976) at Figure 2. and Figure 6-7
- Photo of jaw of Novisuccinea chittenangoensis by Solem (1976) at Figure 17.