Seaturtles: Cheloniidae

Perhaps the most famous behavior of seaturtles is migration (my-GRAY-shun). An individual seaturtle may travel hundreds of miles to go from its feeding area to its nesting site and back. Usually, the feeding grounds are in temperate waters, which are neither very warm nor very cold; the nesting areas, on the other hand, are in tropical waters, which are very warm. The distance between the two places can result in a trek, or journey, of 190 miles (306 kilometers) or more, one way. When the winter months arrive, many turtles migrate (MY-grayt) to warmer tropical waters, but some drop down to the muddy bottoms of coastal waters and bury themselves there to survive the coldest temperatures.

Female seaturtles typically produce several clutches, or nests, of eggs in a season—sometimes seven or more—but they do so only once every two or three years. Rarely, a seaturtle will nest every year. In some cases, the female turtles will gather offshore in groups. Members of these groups clamber onto shore to make nests near one another. The females of almost all species wait until nightfall to dig their nests and lay their eggs. The round eggs are leathery and range from about 1 to 2 inches (2.5–5 centimeters) in diameter, or width across each egg. A single clutch may contain up to 250 eggs, but 90–130 is more common. The eggs hatch in forty to seventy days. As with most turtles, the outdoor temperature during their incubation (ing-kyuh-BAY-shun), or the period of time before the eggs hatch, determines whether the egg will become a male or female upon hatching. When the weather is warm, more females hatch; males usually hatch when the weather is cooler.