History And Fossil Record, Morphology, Ecology, Behavior And Life History, Side-neck TurtlesClassification, Turtles and humans
Turtles are familiar, four-legged reptiles whose body is enclosed within a bony shell. Turtles constitute the reptilian order Testudines. The 257 living species inhabit all continents except Antarctica, plus many islands, and there are marine turtles in all tropical and temperate oceans.
The turtles are separated into two major groups (subclasses) that can be readily identified by the way they retract their head into their shell.
Turtles as food
Large tortoises have long been used by humans as a source of meat. Some species have become extinct because of over-hunting for this purpose. The only surviving giant tortoises live on islands that were relatively recently discovered by people, such as Aldabra in the Indian Ocean, and the Galápagos Islands in the Pacific. The giant tortoises of the Galápagos Islands were hunted by whalers because they could be kept alive for months in the hold of a ship, providing a source of fresh meat during the long whaling season. Female tortoises were preferred for this purpose, because the mature males were too heavy to carry. As a result, some islands were left only with large male tortoises. Predation of young tortoises by goats and rats introduced from the ships contributed to the population decline, and most of the giant tortoises are now endangered.
According to accounts of sailors of the sixteenth and seventeenth centuries, sea turtles used to occur in great flotillas in regions such as the Caribbean. However, all species of sea turtles, but especially the green turtle (Chelonia mydas), were (and are) hunted for their meat. In addition, the hawksbill (Eretmochelys imbricata) was killed for its beautiful "tortoise shell," which can be made into combs and ornaments (these are now illegal in the United States). The sea turtles are most vulnerable on their nesting beaches, where people and other predators may easily take the eggs and the female turtles. In spite of conservation measures initiated by many countries, sea turtle populations are continuing to decline throughout their range.
The American salt-water terrapin (Malaclemmys terrapin) has also been eaten in large numbers, and declined precipitously in abundance. Fortunately, the initiation of conservation measures resulted in the survivors increasing to a greater abundance today.
Even the snapping turtle, one of the most common turtles in North America, has been over-exploited as a source of food. Turtle soup from these animals has been especially popular in Philadelphia, and for several decades a major soup company used thousands of turtles per year to supply the commercial demand, and others were used by restaurant chefs.
- Turtles - History And Fossil Record
- Turtles - Morphology
- Turtles - Ecology
- Turtles - Behavior And Life History
- Turtles - Side-neck Turtles
- Turtles - Hidden-neck Turtles
- Turtles - Captive Turtles
- Turtles - The Future Of Turtles
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