Family Cheloniidae (sea Family Chelydridae (snapping turtles)
Family Dermatemydidae (Mesoamerican river turtle)
Family Dermochelyidae (leatherback turtle)
Family Emydidae (box turtles and pond turtles)
Family Kinosternidae (mud turtles and musk turtles)
Family Pelomedusidae (Afro-American side-necked turtles)
Family Testudinidae (tortoises)
Family Trionychidae (softshell turtles)
SEA TURTLES - 7 SPECIES
CHELONIIDAE is further classified as :
Loggerhead (Caretta Caretta)
Green turtle (Chelonia Mydas)
Leather back (Dermochelys Coriacea)
Hawksbill (Eretmochelys Imbricata)
Kemp’s ridley (Lepidochelys Kempii)
Olive ridley (Lepidochelys Olivacea)
Flatback (Natator Depressa)
Turtles & Tortoises
Generally a tortoise is the term for the animal that lives exclusively on land. A turtle is amphibious.
Turtles and tortoises have been on our earth for about 200 million years.
What is the difference between a turtle and a tortoise?
In common usage in the United States, the word turtle is an inclusive word that refers to all species of water turtle, sea turtle, box turtle, terrapin and tortoise. The word tortoise refers to a particular type of turtle that is well adapted to life on land.
A tortoise is a land dwelling turtle with high domed shell and columnar, elephant-shaped hind legs. Tortoises go to water only to drink or bathe.
In contrast, the word turtle is used for other turtles: pond turtles, river turtles, box turtles, musk turtles, sea turtles, etc.
Tortoises have rather heavy shells. In contrast, sea turtles and soft-shelled turtles that live continuously in water have lighter shells, which help them avoid sinking in water and increase their swimming speed and agility.
The sea turtles occur worldwide in all tropical oceans. They are truly marine, with females coming ashore only to nest. These are the only turtles whose front limbs are stronger than their back limbs.
The shell is oval or heart-shaped. The limbs are modified into flippers for swimming and cannot support the weight of the turtle on land. Sea turtles have lost the ability to retract the head within the shell.
The shell is the turtle's natural protection; it protects its body from predators, so its shell is really important to the turtle.
The shell is like part of the skeleton. It is like an exoskeleton. The appearance is a key part of how to identify a turtle or tortoise. Inside the shell there is space for its body parts.
Turtles & Tortoises
A special thing about the shell is that the turtle cannot come out of its shell completely because part of its backbone is attached to the shell.
The top part of the shell is called a carapace and the bottom part of the shell is called the plastron. Not all shells are hard; some have soft shells, which unfortunately makes it easier for predators to eat them.
The turtle's shell is made out of the same material as our hair and fingernails.
Turtles can see in colour, not in black and white like lots of other animals.
Sea turtles drink salt water then squeeze out the extra salt through very special tear glands.
Sea turtles and tortoises have very different habitats. The sea turtles live in the water but also go onto shore or beaches to lay thousands of eggs. Tortoises live on land, but they go onto the water to cool down.
All turtles and tortoises sit under the warm sun to heat up.
When sea turtles mate they go out of water and try to find a place to mate and lay around 100 eggs. The turtles come out of the sea and select a site in which to lay their eggs. They then clear the area and dig a pit in the sand. Next they lay their eggs and then proceed to fill in the pit in with their hind limbs. After the site is disguised, the turtles return to the sea. After hatching, hundreds of baby sea turtles run for the water because their life depends on making it there.
When sea turtles are born, they are usually smaller than a human hand.
The main predators of the turtles and tortoises are humans. We hunt them for pets, their eggs, shells and skin. Some people in the world hunt turtles for a living, mainly in Asia and Africa. The turtle hunters have to be careful so they won't damage the shell. It is more valuable than other parts of the turtle or tortoise.
Turtles have their shells ripped from their backs and have their intestines removed while still conscious.
Even decapitation fails to produce rapid death in a turtle (they have exceptional abilities to withstand extreme anoxia). The recommended veterinary procedure to cause rapid and painless death is an overdose of lethal drugs followed by "pithing", destruction of the brain. In Tesco stores in China the turtles are in essence chopped up alive using a large machette-like tool. Turtles remain conscious and aware throughout this procedure.
Softshell turtles are killed by "de-carapacing" with a sharp knife. This is an agonising procedure in which the living internal organs are exposed and removed. The turtle remains fully conscious throughout and dies - many minutes later - as a result of blood loss. The suffering caused in the process is almost unimaginable.
Social behavior consists of a series of head bobs for species and gender recognition, courtship and threat. Head bobbing normally precedes agonistic (combative) behavior between males, although females may also be aggressive.
Prominent chin glands in male tortoises produce a secretion which aids in sex recognition and often evokes combative behavior.
Male combat is most intensive in spring and late summer in the Sonoran Desert. During these encounters, each male stands as high as possible, making short rushes toward his adversary while attempting to use the gular horn at the front of the plastron (undershell) to overturn the other or drive him away. An overturned tortoise can usually right itself using its head and a forelimb; if not, the tortoise may overheat and die under the desert sun.
A loose male dominance hierarchy is apparently established by aggression. Dominant males court and mate with females more often than other males. Courtship involves extensive head bobbing as the male attempts to nip and bite at the edges of the female's carapace and legs while circling her. If the female is receptive, she will move her head from side to side and allow the male to mount her from behind. At this point the female will remain still as the male probes with his tail while grunting and enthusiastically stamping his hind feet. The nuptial embrace continues until the female wanders away.
REMEDIES WE HAVE :
OVUM CHELYDRAE SERPENTINE(snapping turtle)
It is slow, very resistant to food or water shortage. Spends the day searching for food. When in danger it hides under the carapace hibernates. Hibernates from October until the end of April buried in the ground. In captivity it can be tamed very well.
The common snapping turtle can be described as highly aggressive when defending itself. Whenever picked up or molested, the snapper shoots its head forward with incredible speed, its mouth wide open. The jaws close with a loud crunch when the neck reaches its full length, and if it happens to grab something it doesn't let go easily. The snapper's bite is strong, and since their jaws are made not to crush but to cut, even a small snapper can deliver a painful wound.
Larger snappers are easily capable of removing a person's fingers.When bothered, snappers produce an odorous substance from organs located on the sides of the plastron. This reaction disappears in most captive animals used to being handled.
Although snapping turtles are aggressive when defending themselves they are actually quite shy animals, preferring to quickly swim away whenever approached.
Considering the turtle's predatory nature, they are not really vicious. Their " snap " is not an act af aggression, but a defense mechanism, which comes from the way snappers hunt - approaching prey with a slow motion walking movement and grabbing it in the blink of an eye. Their speed is so fantastic, it is hard to tell sometimes when the passing by fish has disappeared.
With many fish in a school a snapper is capable of catching two or three in one strike!
Thus, they should be treated with the respect they deserve, and of course... handled with care.
Snapping turtles are not social creatures. Social interactions are limited to aggressive interactions between individuals, usually males. Snapping turtles can be very vicious when removed from the water, but they become docile when placed back into the water. Snapping turtles like to bury themselves in mud with only their nostrils and eyes exposed. This burying behavior is used as a means of ambushing prey.
Snapping turtles have a small growth on the front of their tongues that resembles a wriggling worm. To capture fish, the snapping turtle opens its mouth to make the "worm" visible. When a fish comes to investigate the lure, the snapping turtle grabs it with its strong jaws.
The Guidance now seems a “force”, a control, an intrusion in their space and they desire to be independent and free.
Yet the world seems harsh, difficult to face.They feel unprotected and vulnerable if they come out of the shell.
Loggerheads have a characteristic large head, with more massive jaws and muscles than other sea turtles. This species is the largest hard-shelled turtle in the world.
For reasons unknown, Atlantic loggerheads are unable to co-exist with the Olive Ridley Turtle.
They have powerful jaws which enable them to crush the hard shells of some prey. The loggerheads are a big part of the diet of local rural communities, such as the Antillean and Caribbean areas. The turtles also provide oxidizing oil, which acts like varnish.
The largest nesting beach for the Olive Ridley Turtle is at the Bhitar Kanika Wildlife Sanctuary on the Bay of Bengal located in Orissa, India.
Male sperm is stored within the female for use throughout the entire breeding season. Mating takes place just offshore of the breeding beaches. Females choose to return to their beach of birth and will do this by remembering the smell of the beach through enhanced chemosensors.
The Olive Ridley turtle is well known for its mass nesting, with 300 or more females at a time coming ashore.
Large groups of turtles have been observed basking together in the afternoons so as to escape the cold water temperatures below them and maintain a warm internal temperature by help of the sun. The Olive Ridley Turtle will normally swim away or dive to deeper water rather than confront a predator, which often are humans.
The Olive Ridley Turtle has a tendency to eat a wide variety of foods which has lead to many attempts on its behalf to ingest trash such as plastic bags and Styrofoam. Surprisingly, in captivity, this species has been observed to be cannibalistic.
LEATHER BACK TURTLE
It has physiological adaptations that prevent the loss of body heat, allowing it to establish a range more poleward than the other sea turtles (Cheloniidae).
Dermochelyids are the largest extant turtles, reaching sizes of 244 cm in carapace length and over 800 kg. The carapace is a composite of osteoderms embedded in a leathery skin, hence the common name.The jaws are very weak and incapable of masticating hard prey.
Virtually no natural predators are known for adult leatherbacks, although sharks, killer whales, and jaguars have been reported to injure adults.
The leatherback has no visible shell. The shell is present but it consists of bones that are buried into its dark brown or black skin.