The common snapping turtle (''Chelydra serpentina'') is a
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of large freshwater
turtle
Turtles are reptiles of the order (biology), order Testudines, characterized by a special turtle shell, shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Crypt ...
in the
family
Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
Chelydridae
The Chelydridae is a family of turtles that has seven extinct and two extant genera. The extant genera are the snapping turtles, ''Chelydra'' and '' Macrochelys''. Both are endemic to the Western Hemisphere. The extinct genera are '' Acherontemys ...
. Its natural range extends from southeastern
Canada
Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
, southwest to the edge of the
Rocky Mountains
The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in great-circle distance, straight-line distance from the northernmost part of Western Can ...
, as far east as
Nova Scotia
Nova Scotia is a Provinces and territories of Canada, province of Canada, located on its east coast. It is one of the three Maritime Canada, Maritime provinces and Population of Canada by province and territory, most populous province in Atlan ...
and
Florida
Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...
. The present-day ''Chelydra serpentina'' population in the Middle
Rio Grande
The Rio Grande ( or ) in the United States or the Río Bravo (del Norte) in Mexico (), also known as Tó Ba'áadi in Navajo language, Navajo, is one of the principal rivers (along with the Colorado River) in the Southwestern United States a ...
suggests that the common snapping turtle has been present in this drainage since at least the seventeenth century and is likely native. The three species of ''
Chelydra
''Chelydra'' is one of the two extant taxon, extant genus, genera of the snapping turtle family, Chelydridae, the other being ''Macrochelys'', the much larger alligator snapping turtle. The snapping turtles are native to the Americas, with ''Che ...
'' and the larger
alligator snapping turtle
The alligator snapping turtle (''Macrochelys temminckii'') is a large species of turtle in the Family (biology), family Chelydridae. They are the largest freshwater turtle in North America. The species is Endemism, endemic to freshwater habitat ...
s (genus ''
Macrochelys
''Macrochelys'' is a genus of very large freshwater turtles in the family Chelydridae, native to the Southeastern and Midwestern United States. Only a single extant species was recognized until 2014, when a study divided it into two or possibly t ...
'') are the only extant chelydrids, a family now restricted to the
Americas
The Americas, sometimes collectively called America, are a landmass comprising the totality of North America and South America.''Webster's New World College Dictionary'', 2010 by Wiley Publishing, Inc., Cleveland, Ohio. When viewed as a sing ...
. The common snapping turtle, as its name implies, is the most widespread.
The common snapping turtle is noted for its combative disposition when out of the water with its powerful beak-like jaws, and highly mobile head and neck (hence the
specific epithet
In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...
''serpentina'', meaning "
snake
Snakes are elongated limbless reptiles of the suborder Serpentes (). Cladistically squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales much like other members of the group. Many species of snakes have s ...
-like"). In water, it is likely to flee and hide underwater in sediment. The common snapping turtle has a life-history strategy characterized by high and variable mortality of embryos and hatchlings, delayed sexual maturity, extended adult longevity, and iteroparity (repeated reproductive events) with low reproductive success per reproductive event.
Females, and presumably also males, in more northern populations mature later (at 15–20 years) and at a larger size than in more southern populations (about 12 years). Lifespan in the wild is poorly known, but long-term mark-recapture data from
Algonquin Park
Algonquin Provincial Park is an Ontario provincial park located between Georgian Bay and the Ottawa River, mostly within the Unorganized South Part of Nipissing District. Established in 1893, it is the oldest provincial park in Canada. Addit ...
in Ontario, Canada, suggest a maximum age over 100 years.
Anatomy and morphology
''C. serpentina'' has a rugged, muscular build with a ridged
carapace
A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the unde ...
(upper shell) that varies in color from tan, brown, and black, although ridges tend to be more pronounced in younger individuals. The straight-line carapace length in adulthood may be nearly , though is more common. ''C. serpentina'' usually weighs . Per one study, breeding common snapping turtles were found to average in carapace length, in
plastron
The turtle shell is a shield for the ventral and dorsal parts of turtles (the Order (biology), order Testudines), completely enclosing all the turtle's vital organs and in some cases even the head. It is constructed of modified bony elements such ...
length and weigh about .
Males are larger than females, with almost all weighing in excess of being male and quite old, as the species continues to grow throughout life. Any specimen above the aforementioned weights is exceptional, but the heaviest wild specimen caught reportedly weighed . Common snapping turtles kept in captivity can be quite overweight due to overfeeding and have weighed as much as . In the northern part of its range, the common snapping turtle is often the heaviest native freshwater turtle.Virginia Herpetological Society: Eastern Snapping Turtle ''Chelydra serpentina serpentina'' /ref>
According to a study by Nakamuta et al. (2016), common snapping turtles have well-developed olfactory organs, nerves, and bulbs that suggest that this species has a great sense of smell.
Ecology and life history
Common habitats are shallow
pond
A pond is a small, still, land-based body of water formed by pooling inside a depression (geology), depression, either naturally or artificiality, artificially. A pond is smaller than a lake and there are no official criteria distinguishing ...
s or
streams
A stream is a continuous body of surface water flowing within the bed and banks of a channel. Depending on its location or certain characteristics, a stream may be referred to by a variety of local or regional names. Long, large stream ...
. Some may inhabit
brackish
Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuari ...
environments, such as
estuaries
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...
. These sources of water tend to have an abundance of
aquatic vegetation
Aquatic plants, also referred to as hydrophytes, are vascular plants and Non-vascular plant, non-vascular plants that have adapted to live in aquatic ecosystem, aquatic environments (marine ecosystem, saltwater or freshwater ecosystem, freshwater ...
due to the shallow pools. Some describe them as habitat generalists as they can occupy most permanent bodies of water. Common snapping turtles sometimes bask—though rarely observed—by floating on the surface with only their carapaces exposed, though in the northern parts of their range, they also readily bask on fallen logs in early spring. In shallow waters, common snapping turtles may lie beneath a muddy bottom with only their heads exposed, stretching their long necks to the surface for an occasional breath. Their nostrils are positioned on the very tip of the snout, effectively functioning as snorkels.Hammer, D.A. (1972). ''Ecological relations of waterfowl and snapping turtle populations''. Ph.D. dissertation, Utah State University, Salt Lake City, UT. 72 pg.
Common snapping turtles are
omnivorous
An omnivore () is an animal that regularly consumes significant quantities of both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize ...
. Important aquatic scavengers, they are also active hunters that use ambush tactics to prey on anything they can swallow, including many
invertebrate
Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate s ...
s,
fish
A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...
,
frog
A frog is any member of a diverse and largely semiaquatic group of short-bodied, tailless amphibian vertebrates composing the order (biology), order Anura (coming from the Ancient Greek , literally 'without tail'). Frog species with rough ski ...
s, other
amphibian
Amphibians are ectothermic, anamniote, anamniotic, tetrapod, four-limbed vertebrate animals that constitute the class (biology), class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all Tetrapod, tetrapods, but excl ...
s,
reptile
Reptiles, as commonly defined, are a group of tetrapods with an ectothermic metabolism and Amniotic egg, amniotic development. Living traditional reptiles comprise four Order (biology), orders: Testudines, Crocodilia, Squamata, and Rhynchocepha ...
s (including snakes and smaller turtles), unwary
bird
Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...
s, and small
mammal
A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...
s. In a recent study, young common snapping turtles showed that their lower bite force matches their active foraging behavior, meaning they have to travel and seek out more prey to make up for their inability to eat some items. In some areas adult common snapping turtles can occasionally be incidentally detrimental to breeding
waterfowl
Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which i ...
, but their effect on such prey as ducklings and goslings is frequently exaggerated. As omnivorous scavengers though, they will also feed on
carrion
Carrion (), also known as a carcass, is the decaying flesh of dead animals.
Overview
Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures ...
and a surprisingly large amount of aquatic vegetation.
Common snapping turtles have few predators when older, but eggs are subject to predation by
crow
A crow is a bird of the genus ''Corvus'', or more broadly, a synonym for all of ''Corvus''. The word "crow" is used as part of the common name of many species. The related term "raven" is not linked scientifically to any certain trait but is rathe ...
s,
American mink
The American mink (''Neogale vison'') is a semiaquatic species of Mustelidae, mustelid native to North America, though human introduction has expanded its range to many parts of Europe, Asia, and South America. Because of range expansion, the Am ...
,
skunk
Skunks are mammals in the family Mephitidae. They are known for their ability to spray a liquid with a strong, unpleasant scent from their anal glands. Different species of skunk vary in appearance from black-and-white to brown, cream or gi ...
raccoon
The raccoon ( or , ''Procyon lotor''), sometimes called the North American, northern or common raccoon (also spelled racoon) to distinguish it from Procyonina, other species of raccoon, is a mammal native to North America. It is the largest ...
s. Egg predators use three types of cues to locate turtle nests:
*Visual cues – seeing where the female has dug the soil for the nest chamber and seeing the turtle
*Tactile cues – soft surface around the nest site
*Chemosensory cues – scent of the musk of the female that she leaves on the surface of the soil as she digs
As hatchlings and juveniles, most of the same predators will attack them as well as
heron
Herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 75 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genus ''Botaurus'' are referred to as bi ...
s (mostly
great blue heron
The great blue heron (''Ardea herodias'') is a large wading bird in the heron family Ardeidae, common near the shores of open water and in wetlands over most of North and Central America, as well as far northwestern South America, the Caribbea ...
hawk
Hawks are birds of prey of the family Accipitridae. They are very widely distributed and are found on all continents, except Antarctica.
The subfamily Accipitrinae includes goshawks, sparrowhawks, sharp-shinned hawks, and others. This ...
fish
A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...
, and
snakes
Snakes are elongated Limbless vertebrate, limbless reptiles of the suborder Serpentes (). Cladistically Squamata, squamates, snakes are ectothermic, amniote vertebrates covered in overlapping Scale (zoology), scales much like other members of ...
. There are records during winter in
Canada
Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
of hibernating adult common snapping turtles being ambushed and preyed on by northern river otters. Other natural predators which have reportedly preyed on adults include
coyote
The coyote (''Canis latrans''), also known as the American jackal, prairie wolf, or brush wolf, is a species of canis, canine native to North America. It is smaller than its close relative, the Wolf, gray wolf, and slightly smaller than the c ...
s,
American black bear
The American black bear (''Ursus americanus''), or simply black bear, is a species of medium-sized bear which is Endemism, endemic to North America. It is the continent's smallest and most widely distributed bear species. It is an omnivore, with ...
alligator snapping turtle
The alligator snapping turtle (''Macrochelys temminckii'') is a large species of turtle in the Family (biology), family Chelydridae. They are the largest freshwater turtle in North America. The species is Endemism, endemic to freshwater habitat ...
s. Large, old male common snapping turtles have very few natural threats due to their formidable size and defenses, and tend to have a very low annual mortality rate.
These turtles travel extensively over land to reach new
habitat
In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...
habitat destruction
Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...
, food scarcity, overcrowding, and other factors drive snappers to move; it is quite common to find them traveling far from the nearest water source. Experimental data supports the idea that common snapping turtles can sense the Earth's magnetic field, which could also be used for such movements (together with a variety of other possible orientation cues).
This species mates from April through November, with their peak laying season in June and July. The female can hold
sperm
Sperm (: sperm or sperms) is the male reproductive Cell (biology), cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm ...
for several seasons, using it as necessary. Females travel over land to find sandy soil in which to lay their eggs, often some distance from the water. After digging a hole, the female typically deposits 25 to 80 eggs each year, guiding them into the
nest
A nest is a structure built for certain animals to hold Egg (biology), eggs or young. Although nests are most closely associated with birds, members of all classes of vertebrates and some invertebrates construct nests. They may be composed of ...
with her hind feet and covering them with sand for incubation and protection. These eggs have a leathery, flexible shell and they typically measure only 26–28 mm in diameter.
Incubation time is temperature-dependent, ranging from 9 to 18 weeks. One study on the incubation period of the common snapping turtle incubated the eggs at two temperatures: 20 °C (68 °F) and 30 °C (86 °F). The research found that the incubation period at the higher temperature was significantly shorter at approximately 63 days, while at the lower temperature the time was approximately 140 days. In cooler climates, hatchlings overwinter in the nest. The common snapping turtle is remarkably cold-tolerant; radiotelemetry studies have shown some individuals do not hibernate, but remain active under the ice during the winter. In addition to incubation time, temperature also affects sex determination. It has been shown that females develop at low and high temperatures, while males develop in the intermediate temperature range. Fall temperatures had a positive effect on clutch size and clutch mass, whereas spring temperatures had no impact.
Common snapping turtle hatchlings have recently been found to make sounds before nest exit onto the surface, a phenomenon also known from species in the South American genus ''
Podocnemis
''Podocnemis'' is a genus of aquatic turtles, commonly known as South American river turtles, in the Family (biology), family Podocnemididae. The genus consists of six Extant taxon, extant species occurring in tropical South America.Ouachita map turtle. These sounds are mostly "clicking" noises, but other sounds, including those that sound somewhat like a “creak” or rubbing a finger along a fine-toothed comb, are also sometimes produced.
In the northern part of their range common snapping turtles do not breathe for more than six months because ice covers their hibernating site. These turtles can get oxygen by pushing their head out of the mud and allowing gas exchange to take place through the membranes of their mouth and throat. This is known as extrapulmonary respiration.
If they cannot get enough oxygen through this method they start to utilize anaerobic pathways, burning sugars and fats without the use of oxygen. The metabolic by-products from this process are acidic and create very undesirable side effects by spring, which are known as oxygen debt. Although designated as "least concern" on the
IUCN
The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...
redlist, the species has been designated in the Canadian part of its range as "Special Concern" due to its life history being sensitive to disruption by anthropogenic activity.
Systematics and taxonomy
Currently, no
subspecies
In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...
of the common snapping turtle are recognized. The former Florida subspecies ''osceola'' is currently considered a synonym of ''serpentina'', while the other former subspecies '' Chelydra rossignonii'' and '' Chelydra acutirostris'' are both recognized as full species.
Behavior
When they encounter a species unfamiliar to them such as humans, in rare instances, they will become curious and survey the situation and even more rarely may bump their nose on a leg of the person standing in the water. Although common snapping turtles have fierce dispositions, when they are encountered in the water or a swimmer approaches, they will slip quietly away from any disturbance or may seek shelter under mud or grass nearby.
Relationship with humans
As food
The common snapping turtle is a traditional ingredient in turtle soup; consumption in large quantities, however, can become a health concern due to potential concentration of toxic environmental pollutants in the turtle's flesh.
Captivity
The common snapping turtle is not an ideal pet. Its neck is very flexible, and a wild turtle can bite its handler even if picked up by the sides of its shell. The claws are as sharp as those of
bears
Bears are carnivoran mammals of the family Ursidae (). They are classified as caniforms, or doglike carnivorans. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout most o ...
and cannot be trimmed as can dog claws. The turtle uses its paws like a bear for hunting and slicing food, while biting it. Despite this, a common snapping turtle cannot use its claws for either attacking (its legs have no speed or strength in "swiping" motions) or eating (no opposable thumbs), but only as aids for digging and gripping. Veterinary care is best left to a reptile specialist. A wild common snapping turtle will make a hissing sound when it is threatened or encountered, but they prefer not to provoke confrontations.
It is a common misconception that common snapping turtles may be safely picked up by the tail with no harm to the animal; in fact, this has a high chance of injuring the turtle, especially the tail itself and the
vertebra
Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spina ...
l column. Lifting the turtle with the hands is difficult and dangerous. Snappers can stretch their necks back across their own carapace and to their hind feet on either side to bite. When they feel stressed, they release a musky odor from behind their legs.
It may be tempting to rescue a common snapping turtle found on a road by getting it to bite a stick and then dragging it out of immediate danger. This action can, however, severely scrape the legs and underside of the turtle and lead to deadly infections in the wounds. The safest way to pick up a common snapping turtle is by grasping the carapace behind the back legs, being careful to not grasp the tail. There is a large gap behind the back legs that allows for easy grasping of the carapace and keeps hands safe from both the beak and claws of the turtle. It can also be picked up with a shovel, from the back, making sure the shovel is square across the bottom of the shell. The easiest way, though, is with a blanket or tarp, picking up the corners with the turtle in the middle.
Common snapping turtles are raised on some
turtle farm
Turtle farming is the practice of raising turtles and tortoises of various species commercially. Raised animals are sold for use as gourmet food, traditional medicine ingredients, or as pets. Some farms also sell young animals to other farms, ei ...
s in Mainland China.
In politics
The common snapping turtle was the central feature of a famous American
political cartoon
A political cartoon, also known as an editorial cartoon, is a cartoon graphic with caricatures of public figures, expressing the artist's opinion. An artist who writes and draws such images is known as an editorial cartoonist. They typically co ...
. Published in 1808 in protest at the Jeffersonian
Embargo Act of 1807
The Embargo Act of 1807 was a general trade embargo on all foreign nations that was enacted by the United States Congress. Much broader than the ineffectual 1806 Non-importation Act, it represented an escalation of attempts to persuade Br ...
, the cartoon depicted a common snapping turtle, jaws locked fiercely to an American trader who was attempting to carry a barrel of goods onto a
British
British may refer to:
Peoples, culture, and language
* British people, nationals or natives of the United Kingdom, British Overseas Territories and Crown Dependencies.
* British national identity, the characteristics of British people and culture ...
ship. The trader was seen whimsically uttering the words "Oh! this cursed Ograbme" ("
embargo
Economic sanctions or embargoes are commercial and financial penalties applied by states or institutions against states, groups, or individuals. Economic sanctions are a form of coercion that attempts to get an actor to change its behavior throu ...
" spelled backwards, and also "O, grab me" as the turtle is doing). This piece is widely considered a pioneering work within the
genre
Genre () is any style or form of communication in any mode (written, spoken, digital, artistic, etc.) with socially agreed-upon conventions developed over time. In popular usage, it normally describes a category of literature, music, or other fo ...
of the modern political cartoon.
In 2006, the common snapping turtle was declared the state reptile of New York by vote of the New York Legislature after being chosen by the state's public
elementary school
A primary school (in Ireland, India, the United Kingdom, Australia, New Zealand, Trinidad and Tobago, Jamaica, South Africa, and Singapore), elementary school, or grade school (in North America and the Philippines) is a school for primary ...
children.
Reputation
While it is widely rumored that common snapping turtles can bite off human fingers or toes, and their powerful jaws are more than capable of doing so, no proven cases have ever been presented for this species, as they use their overall size and strength to deter would-be predators. Common snapping turtles are "quite docile" animals underwater that prefer to avoid confrontations rather than provoke them.
The ability to bite forcefully is extremely useful for consuming hard-bodied prey items such as mollusks, crustaceans, and turtles along with some plant matter, like nuts and seeds. In 2023, a study done by Lagrange et al. found that the common snapping turtle (''Chelydra serpentina'') registered between 62 and 564
Newtons
The newton (symbol: N) is the unit of force in the International System of Units (SI). Expressed in terms of SI base units, it is 1 kg⋅m/s2, the force that accelerates a mass of one kilogram at one metre per second squared.
The unit i ...
of force when it came to jaw strength. In comparison, the average bite force of a human (
molars
The molars or molar teeth are large, flat tooth, teeth at the back of the mouth. They are more developed in mammal, mammals. They are used primarily to comminution, grind food during mastication, chewing. The name ''molar'' derives from Latin, '' ...
area) is between 300 and 700 Newtons. Another non-closely related species known as the
alligator snapping turtle
The alligator snapping turtle (''Macrochelys temminckii'') is a large species of turtle in the Family (biology), family Chelydridae. They are the largest freshwater turtle in North America. The species is Endemism, endemic to freshwater habitat ...
has been known to bite off fingers, and at least three documented cases are known.
Invasive species
In recent years in
Italy
Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...
, large mature adult ''C. serpentina'' turtles have been taken from bodies of water throughout the country. They were most probably introduced by the release of unwanted pets. In March 2011, an individual weighing was captured in a canal near
Rome
Rome (Italian language, Italian and , ) is the capital city and most populated (municipality) of Italy. It is also the administrative centre of the Lazio Regions of Italy, region and of the Metropolitan City of Rome. A special named with 2, ...
; another individual was captured near Rome in September 2012.
In
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
, the species was introduced as an exotic pet in the 1960s; it has been recorded as the source of serious bite injuries. In 2004 and 2005, some 1,000 individuals were found in
Chiba Prefecture
is a Prefectures of Japan, prefecture of Japan located in the Kantō region of Honshu. Chiba Prefecture has a population of 6,278,060 (1 June 2019) and has a geographic area of . Chiba Prefecture borders Ibaraki Prefecture to the north, Saitama ...
, making up the majority of individuals believed to have been introduced.
Conservation
The species is currently classified as
Least Concern
A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wil ...
by the
IUCN
The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...
, but has declined sufficiently due to pressure from collection for the pet trade and habitat degradation that Canada and several U.S. states have enacted or are proposing stricter conservation measures. In Canada, it is listed as "Special Concern" in the Species at Risk Act in 2011 and is a target species for projects that include surveys, identification of major habitats, investigation and mitigation of threats, and education of the public including landowners. Involved bodies include governmental departments, universities, museums, and citizen science projects.
Although common snapping turtles are listed as a species of least concern, anthropogenic factors still may have major effects on populations. Decades of road mortality may cause severe population decline in common snapping turtle populations present in urbanized wetlands. A study in southwestern Ontario monitored a population near a busy roadway and found a loss of 764 individuals in only 17 years. The population decreased from 941 individuals in 1985 to 177 individuals in 2002. Road mortality may put common snapping turtle populations at risk of extirpation. Exclusion fencing could aid in decreasing population loss.
References
Further reading
* Behler JL, King FW (1979). ''The Audubon Society Field Guide to North American Reptiles and Amphibians''. New York: Alfred A. Knopf. 743 pp. . (''Chelydra serpentina'', pp. 435–436 + Plates 322–324).
* Conant R (1975). ''A Field Guide to Reptiles and Amphibians of Eastern and Central North America, Second Edition''. Boston: Houghton Mifflin Company. xviii + 429 pp. + Plates 1–48. (hardcover), (paperback). (''Chelydra serpentina'', pp. 37–38 + Plates 5, 11 + Map3).
* Goin CJ, Goin OB, Zug GR (1978). ''Introduction to Herpetology, Third Edition''. San Francisco: W.H. Freeman and Company. xi + 378 pp. . (''Chelydra serpentina'', pp. 122, 142, 258).
* Linnaeus C (1758). ''Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio Decima, Reformata.'' Stockholm: L. Salvius. 824 pp. (''Testudo serpentina'', new species, p. 199). (in Latin).
* Smith HM, Brodie ED Jr (1982). ''Reptiles of North America: A Guide to Field Identification''. New York: Golden Press. 240 pp. . (''Chelydra serpentina'', pp. 38–39).
* Zim HS, Smith HM (1956). ''Reptiles and Amphibians: A Guide to Familiar American Species: A Golden Nature Guide''. New York: Simon and Schuster. 160 pp. (''Chelydra serpentina'', pp. 19, 24, 155).
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