Eventually it was accepted that the planets, including Earth, did in fact orbit around the sun while various moons orbited their respective planets. It wasn't until the reintroduction of this model in the 16th century by Nicolas Copernicus that it began to spread and overtake the old geocentric model. This heliocentric model was disregarded, and often violently opposed by supporters of the geocentric model (particularly the Catholic Church and other religious bodies who believed, for obvious reasons, that the Earth and humanity were the center of creation) for hundreds of years. An opposing theory was put forth approximately 300 years later which placed the sun at the center of the universe with all the planets, Earth included, revolving around it. These models were based on the observable fact that the sun, moon and stars all appear to circle the earth. There were many variations of this model throughout the ages but they all feature the Earth as the center of a revolving universe. Bycatch of hawksbill turtles (accidental capture by commercial and sport fishermen) is being reduced by fishing gear modifications (such as the use of TEDs, or turtle exclusion devices), changes to fishing practices, and closures of certain areas to fishing during nesting and hatching seasons.The first explanations for the movements of the sun, moon, stars and planets throughout the night sky were developed approximately 2600 years ago with the creation of the geocentric model. Hawksbill turtles are protected by various international treaties and agreements, as well as national laws. Any distraction from their dash to the water is an opportunity for predators to pick up an easy meal. Beachfront lighting causes hatchlings to mistake the artificial light for their true destination-the moonlit sea. Their nesting habitat is threatened by degradation from coastal development and beach armoring. As coral reef habitats continue to decline, the hawksbill’s primary source of food is reduced, putting the sea turtles at greater and greater risk. Marine pollution and debris, watercraft strikes, and incidental take from commercial fishing operations also contribute to human-related deaths. In addition hawksbills are harvested for their meat. The shell is used to make jewelry, hair decorations, and other ornaments, and even though international trade of the hawksbill is prohibited, it continues in much of the world. The hawksbill’s beautiful, translucent shell is unfortunately one of its greatest liabilities. Hawksbill sea turtles are internationally listed as critically endangered, and the reptile has been federally listed as an endangered species since 1970. The normal lifespan of hawksbill turtles is thought to be about 30 to 50 years. As a result, actual age at sexual maturity is not known. However, the time required to reach 14 inches is unknown and growth rates vary geographically. They are believed to begin breeding about 25 to 35 years later. Several Yucatán beaches account for 25 to 30 percent of all hawksbill nesting in the Caribbean.īy the time they reach 14 inches (35 centimeters) in length, hawksbills tend to move onto reef habitat.
The exceptions are the Gulf and Caribbean coasts of the Yucatán Peninsula, Mexico, where hawksbills nest on long expanses of beach in densities of 20 to 30 nests a kilometer. In contrast to all other sea turtle species, hawksbills usually nest in low densities on scattered small beaches.
Hatchlings use the bright, open view of the night sky over the water to find their way to the sea. After the incubation period, two-inch (five-centimeter) hatchlings emerge as a group. Caribbean, a clutch size is about 140 eggs. Hawksbills nest at night, laying three to six clutches a season at two week intervals. The nesting season in most locations occurs sometime between April and November. Every two to three years, females return to nest on the very same beaches where they themselves hatched, referred to as natal beaches. Like other sea turtles, hawksbill turtles are solitary for most of their lives they meet only to mate.
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