Banff Springs snail
Encyclopedia
The Banff Springs snail, scientific name Physella johnsoni, is a species
of small air-breathing freshwater snail
in the family Physidae
.
Based on molecular research, it appears that Physella johnsoni separated out as a species from Physella gyrina
about 10,000 years ago.
pulmonate gastropod mollusk are approximately the size of unpopped corn kernels
. The largest ones are only about one centimetre long, and like all of the Physidae, the shells are sinistral or coiled left-handed. The snails' diet consists of periphyton
.
The Banff Springs snail was first identified in 1926 in the nine sulphurous hot springs
of Sulphur Mountain in Banff National Park
, Alberta
, Canada, and has been found nowhere else. It is very unusual because it is adapted to life in thermal springs where the water is low in oxygen
and high in hydrogen sulfide
, an environment too harsh for most animals to survive in. Since its discovery, its range has shrunk to just five of the nine hot springs.
listed it in the List of Wildlife Species at Risk as being endangered in Canada.
Parks Canada
is trying to protect the species through education, law enforcement, facility closure and scientific research. In 1996 Parks Canada
started a research and recovery program for the snail including the closure of the swimming pool at the Cave and Basin National Historic Site
. The goals of the program are to maintain self-sustaining populations of the snail, re-establish populations at all historic locations, and hopefully to downlist the species' status.
The snail population fluctuates seasonally. During times when the numbers are critically low, the snail is most vulnerable to human disturbances or natural disasters (like the spring temporarily drying up). While scientists do not know exactly why the population fluctuates so much, it is probably due to changes in water temperature and chemistry or changes to the bacteria and algae. It is estimated that the population varies between 1,500 and 15,000 snails. At its lowest points, the entire population of snails can fit in an ice cream cone, and at its highest, in a one litre milk carton.
Conservation biologist Dwayne Lepitzki believes that the leading cause of the thermal springs drying up and the decline in snail population is climate change. Until 1996, the only recorded instance of any Sulphur Mountain thermal spring drying up was the Upper Hot Spring in 1923, and now it's a regular occurrence.
Every four weeks researchers and volunteers count the snails and analyze the water chemistry. There is also a captive breeding program being performed, and if it is successful, the snails will be introduced back to the four additional springs where the species was historically present. Eggs are currently hatching in captivity; the time from laying to hatching is four to eight days.
Snails are no longer present at Upper Hot, Upper Middle, Kidney, and Vermilion Cool springs. The snails are most populated at the Cave and Basin National Historic Site
.
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 freshwater snail
Freshwater snail
A freshwater snail is one kind of freshwater mollusc, the other kind being freshwater clams and mussels, i.e. freshwater bivalves. Specifically a freshwater snail is a gastropod that lives in a watery non-marine habitat. The majority of freshwater gastropods have a shell, with very few exceptions....
in the family Physidae
Physidae
Physidae, common name bladder snails, are a monophyletic taxonomic family of small freshwater snails, aquatic pulmonate gastropod molluscs in the clade Hygrophila....
.
Based on molecular research, it appears that Physella johnsoni separated out as a species from Physella gyrina
Physella gyrina
Physella gyrina common name the "tadpole physa", is a species of small, left-handed or sinistral, air-breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Physidae.-Shell description:...
about 10,000 years ago.
Description, habitat and distribution
This species of aquaticAquatic animal
An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life. It may breathe air or extract its oxygen from that dissolved in water through specialised organs called gills, or directly through its skin. Natural environments and the animals that...
pulmonate gastropod mollusk are approximately the size of unpopped corn kernels
Corn kernels
Corn kernels are the seeds of maize.Corn kernels are used as pelletized fuel for pellet stoves and furnaces. Corn kernels are a natural pellet, which gives them a huge economic advantage over other man-made biomass pellets and wood pellets....
. The largest ones are only about one centimetre long, and like all of the Physidae, the shells are sinistral or coiled left-handed. The snails' diet consists of periphyton
Periphyton
Periphyton are a complex mixture of algae, cyanobacteria, heterotrophic microbes, and detritus that are attached to submerged surfaces in most aquatic ecosystems. It serves as an important food source for invertebrates, tadpoles, and some fish. It can also absorb contaminants; removing them from...
.
The Banff Springs snail was first identified in 1926 in the nine sulphurous hot springs
Hot Springs
Hot Springs may refer to:* Hot Springs, Arkansas** Hot Springs National Park, Arkansas*Hot Springs, California**Hot Springs, Lassen County, California**Hot Springs, Modoc County, California**Hot Springs, Placer County, California...
of Sulphur Mountain in Banff National Park
Banff National Park
Banff National Park is Canada's oldest national park, established in 1885 in the Rocky Mountains. The park, located 110–180 kilometres west of Calgary in the province of Alberta, encompasses of mountainous terrain, with numerous glaciers and ice fields, dense coniferous forest, and alpine...
, Alberta
Alberta
Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...
, Canada, and has been found nowhere else. It is very unusual because it is adapted to life in thermal springs where the water is low in oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
and high in hydrogen sulfide
Hydrogen sulfide
Hydrogen sulfide is the chemical compound with the formula . It is a colorless, very poisonous, flammable gas with the characteristic foul odor of expired eggs perceptible at concentrations as low as 0.00047 parts per million...
, an environment too harsh for most animals to survive in. Since its discovery, its range has shrunk to just five of the nine hot springs.
Conservation
The reduction in Banff Spring snail population and range is likely attributable to human use of the hot springs, although fluctuating water temperature is also a factor. In April 1997 it became the first living mollusc to be placed on Canada's national list of species at risk. In 2000 it was classified as endangered by COSEWIC and the Canadian Species at Risk ActSpecies at Risk Act
The Species at Risk Act is a piece of Canadian federal legislation which became law in Canada on December 12, 2002. It is designed to meet one of Canada's key commitments under the International Convention on Biological Diversity. The goal of the Act is to protect endangered or threatened...
listed it in the List of Wildlife Species at Risk as being endangered in Canada.
Parks Canada
Parks Canada
Parks Canada , also known as the Parks Canada Agency , is an agency of the Government of Canada mandated to protect and present nationally significant natural and cultural heritage, and foster public understanding, appreciation, and enjoyment in ways that ensure their ecological and commemorative...
is trying to protect the species through education, law enforcement, facility closure and scientific research. In 1996 Parks Canada
Parks Canada
Parks Canada , also known as the Parks Canada Agency , is an agency of the Government of Canada mandated to protect and present nationally significant natural and cultural heritage, and foster public understanding, appreciation, and enjoyment in ways that ensure their ecological and commemorative...
started a research and recovery program for the snail including the closure of the swimming pool at the Cave and Basin National Historic Site
Cave and Basin National Historic Site
The Cave and Basin National Historic Site of Canada is located in the town of Banff, Alberta within the Canadian Rocky Mountains, at the site of natural thermal mineral springs around which Canada's first national park, Banff National Park, was established....
. The goals of the program are to maintain self-sustaining populations of the snail, re-establish populations at all historic locations, and hopefully to downlist the species' status.
The snail population fluctuates seasonally. During times when the numbers are critically low, the snail is most vulnerable to human disturbances or natural disasters (like the spring temporarily drying up). While scientists do not know exactly why the population fluctuates so much, it is probably due to changes in water temperature and chemistry or changes to the bacteria and algae. It is estimated that the population varies between 1,500 and 15,000 snails. At its lowest points, the entire population of snails can fit in an ice cream cone, and at its highest, in a one litre milk carton.
Conservation biologist Dwayne Lepitzki believes that the leading cause of the thermal springs drying up and the decline in snail population is climate change. Until 1996, the only recorded instance of any Sulphur Mountain thermal spring drying up was the Upper Hot Spring in 1923, and now it's a regular occurrence.
Every four weeks researchers and volunteers count the snails and analyze the water chemistry. There is also a captive breeding program being performed, and if it is successful, the snails will be introduced back to the four additional springs where the species was historically present. Eggs are currently hatching in captivity; the time from laying to hatching is four to eight days.
Snails are no longer present at Upper Hot, Upper Middle, Kidney, and Vermilion Cool springs. The snails are most populated at the Cave and Basin National Historic Site
Cave and Basin National Historic Site
The Cave and Basin National Historic Site of Canada is located in the town of Banff, Alberta within the Canadian Rocky Mountains, at the site of natural thermal mineral springs around which Canada's first national park, Banff National Park, was established....
.