{{Otheruses}}{{pp-semi-protected|small=yes}}{{Otheruses}}{{pp-semi-protected|small=yes}}
{{Taxobox
| name = Alligator Snapping Turtle
| status = VU | status_system = IUCN2.3
| image = Alligator snapping turtle.jpg
| image_width = 250px
| regnum =
AnimalAnimals are a major group of mostly multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously...
ia
| phylum = Chordata
| classis =
ReptiliaReptiles, or members of the class Reptilia, are air-breathing, generally "cold-blooded" amniotes that generally have skin covered in scales or scutes. They are tetrapods and lay amniote eggs, whose embryos are surrounded by the amnion membrane...
| ordo = Testudines
| familia =
ChelydridaeThere are two extant species of the family Chelydridae: Chelydra serpentina, the Common Snapping Turtle, and its larger relative Macrochelys temminckii, the Alligator Snapping Turtle...
| genus =
Macrochelys
| species =
M. temminckii
| binomial =
Macrochelys temminckii
| binomial_authority =
TroostGerald Troost was an American-Dutch medical doctor, naturalist, mineralogist, and founding member and first president of the Philadelphia Academy of Natural Sciences....
, 1835
| synonyms =
Macroclemmys temminckiiBoulengerGeorge Albert Boulenger was a Belgian-British zoologist who identified over 2000 new animal species, chiefly fish, reptiles and amphibians.-Life:...
, 1889Chelonura temminckiiTroost, 1835Testudo planitiaGmelinJohann Friedrich Gmelin was a German naturalist, botanist and entomologist.- Education :Johann Friedrich Gmelin was born as the eldest son of Philipp Friedrich Gmelin in 1748 in Tübingen...
, 1789
}}
The
Alligator Snapping Turtle (
Macrochelys temminckii) is one of the largest freshwater turtles in the world. It is a larger and less aggressive{{Citation needed|date=October 2009}} relative of the Common Snapping Turtle. The epithet
temminckii is in honor of Dutch
zoologistZoology, also spelled zoölogy, is the branch of biology that focuses on the structure, function, behavior, and evolution of animals. The zoologist's pronunciation of "zoology" is , though a common spelling pronunciation is .-Systems of classification:...
Coenraad Jacob TemminckCoenraad Jacob Temminck was a Dutch aristocrat and zoologist.Temminck was the first director of the National Natural History Museum at Leiden from 1820 until his death. His Manuel d'ornithologie, ou Tableau systematique des oiseaux qui se trouvent en Europe was the standard work on European birds...
.
Distribution and habitat
The largest freshwater turtle in North America, the alligator snapper keeps to primarily southern U.S. waters, while the smaller, more aggressive
common snapperThe Common Snapping Turtle is a large freshwater turtle of the family Chelydridae. Its natural range extends from southeastern Canada south, west to the Rocky Mountains , throughout Mexico, and as far south as Ecuador...
inhabits lakes and streams from South America to Canada. These turtles can remain submerged for three hours. Typically only nesting females will venture onto open land.
Surprisingly, due to the pet trade and other factors the species has found its way to Asia and Europe with a breeding/research center found in
Japanis an island country in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, People's Republic of China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
.
Description
The Alligator Snapping Turtle is characterized by a large, heavy head, and a long, thick shell with three dorsal ridges of large scales (osteoderms) giving it a primitive appearance reminiscent of some of the plated
dinosaur{{Otheruses}}{{pp-semi-protected|small=yes}}{{Otheruses}}{{pp-semi-protected|small=yes}}{{Taxobox|name = Dinosaurs|fossil_range = {{Fossil range|230|65|earliest=230|latest=0|PS=
Descendant taxon Aves survives to present.}}|image = field_dinos_2.jpg...
s. They can be immediately distinguished from the Common Snapping Turtle by the three distinct rows of spikes and raised plates on the
carapaceA carapace is a dorsal 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 chelonians, order Testudines, turtles and tortoises.-Crustaceans:In crustaceans, the carapace is a part of the exoskeleton...
, whereas the Common Snapping Turtle has a smoother carapace
. They are a solid gray,
brownBrown is a color term, denoting a wide range of composite colors produced by a mixture of orange, red or yellow with black. The term is from Old English brún, in origin denoting any dusky or dark shade of color....
,
blackBlack is the color of objects that do not emit or reflect light in any part of the visible spectrum; they absorb all such frequencies of light...
, or olive-
greenGreen is a color, the perception of which is evoked by light having a spectrum dominated by energy with a wavelength of roughly 520–570 nanometres. In the subtractive color system, it is not a primary color, but is created out of a mixture of yellow and blue, or yellow and cyan; it is considered...
in color, and often covered with
algaeAlgae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms. The largest and most complex marine forms are called seaweeds. They are photosynthetic, like plants, and "simple" because they lack the many distinct organs found in...
. They have radiating
yellowYellow is the color evoked by light that stimulates both the L and M cone cells of the retina about equally, with no significant stimulation of the S cone cells. Light with a wavelength of 570–580 nm is yellow, as is light with a suitable mixture of somewhat longer and shorter wavelengths...
patterns around the eyes, serving to break up the outline of the
eyeEyes are organs that detect light, and send electrical impulses along the optic nerve to the visual and other areas of the brain. Complex optical systems with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system...
and keep the turtle
camouflageCamouflage is a method of crypsis that allows an otherwise visible organism or object to remain indiscernible from the surrounding environment through deception. Examples include a tiger's stripes and the battledress of a modern soldier...
d. Their eyes are also surrounded by a star-shaped arrangement of fleshy filamentous "eyelashes."
There is an unverified report of a 403-
poundThe pound or pound-mass is a unit of mass used in the imperial, United States customary and other systems of measurement...
Alligator Snapping Turtle found in the
Neosho RiverThe Neosho River is a tributary of the Arkansas River in eastern Kansas and northeastern Oklahoma in the United States. Its tributaries also drain portions of Missouri and Arkansas. The river is about 460 mi long...
in
KansasKansas is a state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa tribe, who inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south wind," although this was...
in 1937, but the largest one actually on record is debatable. One weighed at the The Shedd aquarium in
ChicagoChicago is the largest city in the U.S. state of Illinois, and with more than 2.8 million people, the 3rd largest city in the United States...
was a 16-year resident giant alligator snapper weighing 249 lbs. sent to the Tennessee State Aquarium as part of a breeding loan in 1999. Another was 236 lbs, and housed at the
Brookfield ZooThe Brookfield Zoo is a zoo located in the Chicago suburb of Brookfield, Illinois. The zoo covers an area of 216 acres and houses around 450 species of animals....
in suburban
ChicagoChicago is the largest city in the U.S. state of Illinois, and with more than 2.8 million people, the 3rd largest city in the United States...
. Both of these may still be alive. Further research is required. They generally do not grow quite that large. Average adult size is around 26 inches shell length with a weight of 175 lb. Males are typically larger than females. Alligator snapping turtles can also range in length from 16 to 32 inches (40.4 to 80.8 cm).
In
mature specimens (carapace length over 12 inches) male and female can be differentiated by the position of the
cloacaIn zoological anatomy, a cloaca is the posterior opening that serves as the only such opening for the intestinal, reproductive and urinary tracts of certain animal species. The word comes from Latin, and means sewer...
from the
carapaceA carapace is a dorsal 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 chelonians, order Testudines, turtles and tortoises.-Crustaceans:In crustaceans, the carapace is a part of the exoskeleton...
and the thickness of the tail's base. A mature male's cloaca extends beyond the carapace edge, a female's is placed exactly on the edge if not nearer to the
plastronThe plastron is the nearly flat part of the shell structure of a turtle or tortoise, what one would call the belly, similar in composition to the carapace; with an external layer of horny material divided into plates called scutes and an underlying layer of interlocking bones.In certain families...
. The base of the tail of the male is also thicker as compared to females because of the reproductive organs.
The inside of the turtle's mouth is camouflaged, and it possesses a vermiform (literally, "worm-shaped")
appendageAn appendage in the broadest sense is an additional or subsidiary part existing on, or added to, something which can generally still function if the appendage has never existed or is later provided or grown, or will still perform a primary function if the appendage is removed.- Biological context...
on the tip of its
tongueThe tongue is a muscle on the floor of the mouth that manipulates food for chewing and swallowing . It is the primary organ of taste, as much of the upper surface of the tongue is covered in papillae and taste buds. A secondary function of the tongue is speech, in which the organ assists...
used to lure
fishA fish is any aquatic vertebrate animal that is typically ectothermic , covered with scales, and equipped with two sets of paired fins and several unpaired fins...
, a form of Peckhamian mimicry. The turtle hunts by lying motionless in the water with its mouth wide open. The vermiform tongue imitates the movements of a worm, luring prey to the turtle's mouth. The mouth is then closed with tremendous speed and force, completing the ambush.
The Alligator Snapping Turtle possesses the second strongest bite strength of any animal in the world{{Citation needed|date=October 2009}}, and can be quite aggressive when cornered. These turtles must be handled with extreme care.
Fossil history
Unlike the
familyIn biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus...
ChelydridaeThere are two extant species of the family Chelydridae: Chelydra serpentina, the Common Snapping Turtle, and its larger relative Macrochelys temminckii, the Alligator Snapping Turtle...
as a whole, the
genusIn biology, a genus is a taxonomic unit used in the classification of living and fossil organisms. The term comes from Latin genus "descent, family, type, gender" , cognate with – genos, "race, stock, kin" ..In addition, genus is a taxonomic rank in the hierarchy In biology, a genus (plural:...
Macroclemys is exclusively North American and is generally considered to contain three valid
speciesIn biology, a species is:* a taxonomic rank or* a unit at that rank ....
: the extant
M. temminckii and the
extinctIn biology and ecology, extinction is the end of an organism or group of taxa. The moment of extinction is generally considered to be the death of the last individual of that species...
M. schmidti and
M. auffenbergi (described from the early middle
MioceneThe Miocene is a geological epoch of the Neogene period and extends from about 23.03 to 5.33 million years before the present . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the...
of
NebraskaNebraska is a state located on the Great Plains of the Midwestern United States. The state's capital is Lincoln and its largest city is Omaha....
and the middle
PlioceneThe Pliocene epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present....
of
FloridaFlorida is a state located in the southeastern region of the United States, bordering Alabama to the northwest and Georgia to the north. It was the 27th state admitted to the United States...
, respectively).
Diet
Alligator snappers are opportunistic carnivores more often at a young age, but are also scavengers. In northern states such as Michigan young hatchlings will live off plants also, such as water lettuce and other floating grass, shrub, and flower-like organisms. They usually obtain this behavior when food is scarce or when it is early in the summer months. As they mature they become omnivores and do not pose a threat to fish populations. Fishermen have glorified the species' ability to catch fish and to deplete fish populations. Minnows are usually the main source of meat for the species at a young age. They will eat almost anything they can catch. Their natural diet consists primarily of fish and dead fish carcasses (usually thrown overboard by fishermen),
invertebrateAn invertebrate is an animal without a vertebral column. The group includes 95% of all animal species — all animals except those in the Chordate subphylum Vertebrata ....
s,
carrionCarrion refers to the carcass of a dead animal. Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters, or scavengers, include Hyenas, Vultures, Canadian Opossum, Tasmanian Devils, Black Bears, Komodo Dragons, Bald Eagles, Raccoons,...
, and
amphibianAmphibians , such as frogs, toads, salamanders, newts, and caecilians, are ectothermic animals that metamorphose from a juvenile water-breathing form, to an adult air-breathing form. Though amphibians typically have four limbs, the Caecilians are notable for being limbless. Unlike other land...
s, but they are also known to eat snakes, and even other turtles. In captivity they may consume almost any kind of meat provided, including beef, chicken and pork although these are not always healthy on a day to day basis. Though not a primary food source for them, adult Alligator snappers have been known to kill and eat small alligators that have been confined with, such as in a net, small bog, or poorly-planned aquarium display.{{Citation needed|date=August 2008}}
Reproduction and lifespan
Maturity is reached at around 12 years of age. Mating takes place yearly; early spring in the southern part of their total range, and later spring in the north. The female builds a nest and lays a clutch of 10-50 eggs about 2 months later. The sex of the baby alligator snapping turtles depends on the temperature at which the eggs are incubated. Nests are typically excavated at least 50 yards from the water's edge to prevent them from being flooded and drowned. Incubation takes from 100 to 140 days, and hatchlings emerge in the early fall.
Though their potential lifespans in the wild are unknown, alligator snapping turtles are believed to be capable of living to 150 years of age. According to an episode of "
Dirty JobsDirty Jobs is a program on the Discovery Channel in which host Mike Rowe is shown performing difficult, strange, disgusting, or messy occupational duties alongside the typical employees. The show premiered with two pilot episodes in November 2003...
" on the
Discovery ChannelDiscovery Channel is an American satellite and cable TV channel , founded by John Hendricks and distributed by Discovery Communications. It provides documentary programming focused primarily on popular science, technology, and history...
, there are reports of living Alligator Snapping turtles with musket balls from the
American Civil WarThe American Civil War , also known as the War Between the States and several other names, was a civil war in the United States of America. Eleven Southern slave states declared their secession from the United States and formed the Confederate States of America...
lodged in them. In captivity, they typically live from anywhere between 20 to 70 years of age.
In captivity
Alligator snapping turtles are often captive-bred as pets and are readily available in the exotic animal trade. Due to their potential size and specific needs, they do not make particularly good pets for any but the most experienced aquatic turtle keepers. Due to sheer size, handling adult specimens can pose significant problems. The turtle can be handled with relative safety by holding them at the sides of the carapace. A large individual can be held by grasping the turtle firmly in the anterior, just behind the head, and posterior portions of the carapace.
Despite their reputation, they are typically not prone to biting, but when antagonized are quite capable of delivering a bite with their powerful jaws which can cause significant harm to a human, easily
amputatingAmputation is the removal of a body extremity by trauma or surgery. As a surgical measure, it is used to control pain or a disease process in the affected limb, such as malignancy or gangrene. In some cases, it is carried out on individuals as a preventative surgery for such problems...
fingers. Some states where alligator snapping turtles do not naturally occur (such as
CaliforniaCalifornia is the most populous state in the United States, and the third largest by area. California is the second most populous sub-national entity in the Americas, behind only São Paulo, Brazil...
) prohibit them from being kept as pets by residents.
Conservation status
The alligator snapping turtle is primarily vulnerable to humans from habitat loss and hunting. Some are hunted for their carapaces; the
plastronThe plastron is the nearly flat part of the shell structure of a turtle or tortoise, what one would call the belly, similar in composition to the carapace; with an external layer of horny material divided into plates called scutes and an underlying layer of interlocking bones.In certain families...
of the turtle is valued because of its shape as a cross. There are accounts of large (50+ lb) turtles being caught both purposely and accidentally on recreational fishing lines called "trot lines." Abandoned trot lines are thought to be even more dangerous to turtles.
SoupTurtle soup is soup or stews made from the flesh of the turtle. The dish is existent in many cultures and is viewed as a luxury or delicacy.The green turtle was commonly used for turtle soup in the United States and United Kingdom, soup made from the snapping turtle was found mainly in the United...
made from snapping turtle meat is considered by some to be a delicacy.
This turtle is protected from collection throughout much of its range. The IUCN lists it as a
threatened speciesThreatened species are any species which are vulnerable to extinction in the near future.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: vulnerable, endangered, and critically...
, and as of June 14, 2006 it was afforded some international protection by being listed as a CITES III species (which will put limits on exportation from the United States and all international trade in this species.).
The alligator snapping turtle is now endangered in several states, including Illinois.
External links
{{Commons|Macrochelys temminckii}}