SPECIES BIOLOGY 



The havvksbill is a small to medium-sized sea turtle. In the U.S. Caribbean, nesting females 

 average about 62-9 1cm in straight carapace length. Weight is typically to 80 kg in the wider 

 Caribbean, with a record weight of 127 kg. Hatchlings average about 42 mm straight carapace 

 length and range in weight from 13.5-19.5 g. The following characteristics distinguish the 

 hawksbill from other sea turtles: two pairs of prefrontal scales; thick, posteriorly overlapping 

 scutes on the carapace; four pairs of costal scutes; two claws on each flipper; and a beak-like 

 mouth. The carapace is heart-shaped in very young turtles, and becomes more elongate with 

 maturity. Its lateral and posterior margins are sharply serrated in all but very old individuals. 

 The epidermal scutes that overlay the bones of the shell are the tortoiseshell of commerce. They 

 are unusually thick, overlap posteriorly on the carapace, and are richly patterned with irregularly 

 radiating streaks of brown or black on an amber background. The scutes of the plastron of 

 Atlantic hawksbills are usually clear yellow, with little or no dark pigmentation. The soft skin on 

 the ventral side is cream or yellow, and may be pinkish-orange in mature individuals. The scales 

 of the head and forelimbs are dark brown or black with sharply defined yellow borders. The 

 head is elongate and tapers sharply to a point. The lower jaw is V-shaped. 



Hawksbills utilize different habitats at different stages of their life cycle. Post-hatchling 

 hawksbills occupy the pelagic environment, taking shelter in weedlines that accumulate at 

 convergence points. Hawksbills re-enter coastal waters when they reach approximately 20-25 

 cm carapace length. Coral reefs are widely recognized as the resident foraging habitat of 

 juveniles, subadults and adults. This habitat association is undoubtedly related to their diet of 

 sponges, which need solid substrate for attachment. The ledges and caves of the reef provide 

 shelter for resting both during the day and night. Hawksbills are also found around rocky 

 outcrops and high energy shoals, which are also optimum sites for sponge growth. Hawksbills 

 are also known to inhabit mangrove-fringed bays and estuaries, particularly along the eastern 

 shore of continents where coral reefs are absent. In Texas, juvenile hawksbills are associated 

 with stone jetties. 



Hawksbills utilize both low- and high-energy nesting beaches in tropical oceans of the world. 

 Both insular and mainland nesting sites are known. Hawksbills will nest on small pocket 

 beaches, and. because of their small body size and great agility, can traverse fringing reefs that 

 limit access by other species. They exhibit a wide tolerance for nesting substrate type and nests 

 are typically placed under vegetation. Age at sexual maturity is not known; however, it is 

 generally believed that hawksbills mature slowly over several decades. 



SPECIES DISTRIBUTION 



The hawksbill occurs in tropical and subtropical waters of the Atlantic, Pacific and Indian 

 Oceans. The species is widely distributed in the Caribbean Sea and western Atlantic Ocean, with 

 representatives of at least some life history stages regularly occurring in southern Florida and the 

 northern Gulf of Mexico (especially Texas); in the Greater and Lesser Antilles; and along the 

 Central American mainland south to Brazil. Within the United States, hawksbills are most 

 common in Puerto Rico and its associated islands, in the U.S. Virgin Islands, and in Florida. In 

 the continental U.S., the species has been recorded in all of the Gulf states and along the eastern 

 seaboard as far north as Massachusetts, with the exception of Connecticut, but sightings north of 

 Florida are rare. 



Hawksbills are observed in Florida with some regularity on the reefs off Palm Beach County, 

 where the warm Gulf Stream current passes close to shore, and in the Florida Keys. Texas is the 

 only other state where hawksbills are sighted with any regularity. Most sightings involve 



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