North Florida Field Office Sea Turtle Information
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- STATUS
- REPRODUCTION AND DEVELOPMENT
- RANGE AND POPULATION LEVEL
- CRITICAL HABITAT
- REASONS FOR CURRENT STATUS
- MANAGEMENT AND PROTECTION
- Kemp’s Ridley Sea Turtle ( Lepidochelys kempii )
- Olive Ridley Sea Turtle ( Lepidochelys olivacea )
- DESCRIPTION
Hawksbill Sea Turtle (Eretmochelys imbricata) F  AMILY: Cheloniidae
STATUS: Endangered throughout its range (Federal Register, June 2, 1970). DESCRIPTION: The hawksbill is a small to medium-sized marine turtle having an elongated oval shell with overlapping scutes on the carapace, a relatively small head with a distinctive hawk-like beak, and flippers with two claws. General coloration is brown with numerous splashes of yellow, orange, or reddish-brown on carapace. The plastron is yellowish with black spots on the intergular and postanal scutes. Juveniles are black or very dark brown with light brown or yellow coloration on the edge of the shell, limbs, and raised ridges of the carapace. As an adult, the hawksbill may reach up to 3 feet in length and weigh up to 300 pounds, although adults more commonly average about 2½ feet in length and weigh between 95 to 165 pounds. It is the only sea turtle with a combination of two pairs of prefrontal scales on the head and four pairs of costal scutes on the carapace. The hawksbill feeds primarily on sponges and is most often associated with the coral reef community. REPRODUCTION AND DEVELOPMENT: The nesting season varies with locality, but in most locations nesting occurs sometime between April and November. Hawksbills nest at night and, on average, about 4.5 times per season at intervals of approximately 14 days. In Florida and the U.S. Caribbean, clutch size is approximately 140 eggs, although several records exist of over 200 eggs per nest. Remigration intervals of 2 to 3 years predominate. The incubation period averages 60 days. Hawksbills are recruited into the reef environment at about 35 cm in length and are believed to begin breeding about 30 years later. However, the time required to reach 35 cm in length is unknown and growth rates vary geographically. As a result, actual age at sexual maturity is not known. RANGE AND POPULATION LEVEL: The hawksbill is found in tropical and subtropical regions of the Atlantic, Pacific, and Indian Oceans. The species is widely distributed in the Caribbean Sea and western Atlantic Ocean. In contrast to all other sea turtle species, hawksbills nest in low densities on scattered small beaches. 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/km, are exceptions. The hawksbill sea turtle has experienced global population declines of 80 percent or more during the past century and continued declines are projected. Most populations are declining, depleted, or remnants of larger aggregations. Only five regional populations remain with more than 1,000 females nesting annually (Seychelles, Mexico, Indonesia, and two in Australia). About 15,000 females are estimated to nest each year throughout the world with the Caribbean accounting for 20 to 30 percent of the world’s hawksbill population. Panama, which used to support the single most important nesting population in the Caribbean, is only a remnant population. Mexico is now the most important region for hawksbills in the Caribbean with 3,000 to 4,500 nests/year. Other significant but smaller populations in the Caribbean still occur in Martinique, Jamaica, Guatemala, Nicaragua, Grenada, Dominican Republic, Turks and Caicos Islands, Cuba, Puerto Rico, and U.S. Virgin Islands. In the U.S. Caribbean, about 100 to 350 nests/year are laid on Mona Island, Puerto Rico, and 60 to 120 nests/year on Buck Island Reef National Monument, U.S. Virgin Islands. In the U.S. Pacific, hawksbills nest only on main island beaches in Hawaii, primarily along the east coast of the island of Hawaii. Hawksbill nesting has also been documented in American Samoa and Guam. HABITAT: Hawksbills frequent rocky areas, coral reefs, shallow coastal areas, lagoons or oceanic islands, and narrow creeks and passes. They are seldom seen in water deeper than 65 feet. Hatchlings are often found floating in masses of sea plants, and nesting may occur on almost any undisturbed deep-sand beach in the tropics. Adult females are able to climb over reefs and rocks to nest in beach vegetation. CRITICAL HABITAT: 50 CFR 17.95 Puerto Rico: (1) Isla Mona. All areas of beachfront on the west, south, and east sides of the island from mean high tide inland to a point 150 meters from shore. This includes all 7.2 kilometers of beaches on Isla Mona. (2) Culebra Island. The following areas of beachfront on the north shore of the island from mean high tide to a point 150 meters from shore: Playa Resaca, Playa Brava, and Playa Larga. (3) Cayo Norte. South beach, from mean high tide inland to a point 150 meters from shore. (4) Island Culebrita. All beachfront areas on the southwest facing shore, east facing shore, and northwest facing shore of the island from mean high tide inland to a point 150 meters from shore. 50 CFR 226.209 Mona and Monito Islands, Puerto Rico – Waters surrounding the islands of Mona and Monito, from the mean high water line seaward to 3 nautical miles (5.6 km). REASONS FOR CURRENT STATUS: The decline of this species is primarily due to human exploitation for tortoiseshell. While the legal hawksbill shell trade ended when Japan agreed to stop importing shell in 1993, a significant illegal trade continues. In addition, there are serious attempts by Cuba, with support from other countries, to downlist hawksbills in Cuba to Appendix 2 of the Convention on International Trade in Endangered Species of Wild Fauna and Flora in order to make it possible to reopen trade with Japan and possibly other countries. Other threats include loss or degradation of nesting habitat from coastal development and beach armoring; disorientation of hatchlings by beachfront lighting; excessive nest predation by native and non-native predators; degradation of foraging habitat; marine pollution and debris; watercraft strikes; and incidental take from commercial fishing operations. MANAGEMENT AND PROTECTION: Since hawksbills migrate long distances and co-mingle extensively on foraging areas, and since there are 36 geopolitical units in the Caribbean, implementing effective conservation measures in the Caribbean is complex and will require long-term cooperation between Caribbean nations for recovery efforts to succeed. The most important hawksbill nesting beaches in the Caribbean occur along the Yucatán Peninsula of Mexico. Several Yucatán beaches account for 25 to 30 percent of all hawksbill nesting in the Caribbean. Since 1985, the Fish and Wildlife Service has provided annual funding for surveying and protecting nests at three key beaches along the Yucatán Peninsula. Continued efforts are needed to protect nesting beaches; minimize the threat from illegal exploitation through intensified law enforcement efforts to curb the incidence of poaching and harassment; maintain the ban on international trade in hawksbill products; and ensure long-term protection of important foraging habitats by designating them as marine sanctuaries or as State, territorial, or Commonwealth aquatic preserves or sanctuaries. Kemp’s Ridley Sea Turtle (Lepidochelys kempii) 
STATUS: Endangered throughout its range (Federal Register, December 2, 1970). DESCRIPTION: The Kemp’s ridley turtle is one of the smallest of the sea turtles, with adults reaching about 2 feet in length and weighing up to 100 pounds. The adult Kemp’s ridley has an oval carapace that is almost as wide as it is long and is usually olive-gray in color. The carapace has five pairs of costal scutes. In each bridge adjoining the plastron to the carapace, there are four inframarginal scutes, each of which is perforated by a pore. The head has two pairs of prefrontal scales. Hatchlings are black on both sides. The Kemp’s ridley has a triangular-shaped head with a somewhat hooked beak with large crushing surfaces. This turtle is a shallow water benthic feeder with a diet consisting primarily of crabs. REPRODUCTION AND DEVELOPMENT: Nesting occurs from April to June during which time the turtles appear off the Tamaulipas and Veracruz coasts of Mexico. Precipitated by strong winds, the females swarm to mass nesting emergences, known as arribadas or arribazones, to nest during daylight hours. Clutch size averages 110 eggs. Some females breed annually and nest an average of 1 to 4 times in a season at intervals of 10 to 28 days. Age at sexual maturity is believed to be between 7 to 15 years. RANGE AND POPULATION LEVEL: The range of the Kemp’s ridley includes the Gulf coasts of Mexico and the U.S., and the Atlantic coast of North America as far north as Nova Scotia and Newfoundland. Most Kemp’s ridleys nest on the coastal beaches of the Mexican states of Tamaulipas and Veracruz, although a very small number of Kemp’s ridleys nest consistently at Padre Island National Seashore, Texas. Hatchlings, after leaving the nesting beach, are believed to become entrained in eddies within the Gulf of Mexico, where they are dispersed within the Gulf and Atlantic by oceanic surface currents until they reach about 20 cm in length, at which size they enter coastal shallow water habitats. The Kemp’s ridley is the most seriously endangered of the sea turtles. Its numbers have precipitously declined since 1947, when over 40,000 nesting females were estimated in a single arribada. The nesting population produced a low of 702 nests in 1985; however, since the mid-1980's, the number of nests laid in a season has been increasing primarily due to nest protection efforts and implementation of regulations requiring the use of turtle excluder devices in commercial fishing trawls. During the 1999 and 2000 nesting seasons, more than 3,600 nests and 6,000 nests, respectively, were deposited on the Mexico nesting beaches. HABITAT: Outside of nesting, the major habitat for Kemp's ridleys is the nearshore and inshore waters of the northern Gulf of Mexico, especially Louisiana waters. Kemp's ridleys are often found in salt marsh habitats. The preferred sections of nesting beach are backed up by extensive swamps or large bodies of open water having seasonal narrow ocean connections. CRITICAL HABITAT: None designated. REASONS FOR CURRENT STATUS: The decline of this species is primarily due to human activities, including the direct harvest of adults and eggs and incidental capture in commercial fishing operations. Today, under strict protection, the population appears to be in the early stages of recovery. MANAGEMENT AND PROTECTION: The recent nesting increase can be attributed to full protection of nesting females and their nests in Mexico, and the requirement to use turtle excluder devices in shrimp trawls both in the United States and Mexico. In 1966, conservation efforts for the Kemp’s ridley were initiated on the beach near Rancho Nuevo in Tamaulipas, Mexico. This locale is the only place in the world where large nesting aggregations of this sea turtle were and are known to occur. From 1966 to 1987, conservation efforts focused on the area of Rancho Nuevo with one turtle protection camp. In 1978, the U.S. joined with Mexico at Rancho Nuevo in a bi-national effort to prevent the extinction of the Kemp’s ridley. In 1988, this bi-national program expanded to the south and another camp was added. In 1989, a third camp was established when the program was expanded to the north of Rancho Nuevo. By 1997, a total of seven camps had been established along the Tamaulipas and Veracruz coasts to allow for increased nest protection efforts. The Mexico government also prohibits harvesting and is working to increase the population through more intensive law enforcement, by fencing nest areas to diminish natural predation, and by relocating all nests into corrals to prevent poaching and predation. While relocation of nests into corrals is currently a necessary management measure, this relocation and concentration of eggs into a "safe" area is of concern since it makes the eggs more susceptible to reduced viability due to movement-induced mortality, disease vectors, catastrophic events like hurricanes, and marine predators once the predators learn where to concentrate their efforts. Olive Ridley Sea Turtle (Lepidochelys olivacea) F  AMILY: Cheloniidae
STATUS: Breeding colony populations on the Pacific Coast of Mexico are listed as Endangered; all others are listed as Threatened (Federal Register, July 28, 1978). DESCRIPTION: The olive ridley was named for the olive color of its heart-shaped shell and is one of the smallest of the sea turtles, with adults reaching 2 to 2½ feet in length and weighing 80 to 110 pounds. The species may be identified by the uniquely high and variable numbers of vertebral and costal scutes. Although some individuals have only five pairs of costals, in nearly all cases some division of costal scutes occurs, so that as many as six to nine pairs may be present. In addition, the vertebral scutes also show frequent division, as do the scales on the dorsal surface of the head. The prefrontal scales, however, typically number two pairs. Existing reports suggest that the olive ridley’s diet includes crabs, shrimp, rock lobsters, jellyfish, and tunicates. In some parts of the world, algae has been reported as its principal food. REPRODUCTION AND DEVELOPMENT: The olive ridley is most noted for its massive nesting aggregations, known as arribadas or arribazones, with literally thousands of females nesting in large simultaneous waves over small stretches of beach. Arribadas may be precipitated by climatic events, such as a strong offshore wind, or by certain phases of the moon and tide, but there is a major element of unpredictability at all arribada sites. Although not every adult female participates in these arribadas, the vast majority do. Olive ridleys typically nest 1 to 3 times per season, producing about 100 to110 eggs on each occasion. The internesting interval is variable, but for most localities it is approximately 14 days for solitary nesters and 28 days for arribada nesters. Incubation takes about 50 to 60 days. Age at sexual maturity is not known, but if similar to its close relative the Kemp’s ridley, it would be 7 to 15 years. RANGE AND POPULATION LEVEL: The olive ridley occurs within the tropical regions of the Pacific, Atlantic, and Indian Oceans. In the Pacific, it nests primarily on beaches from Mexico south to at least Colombia with major nesting beaches at Escobilla, Mexico; La Flor, Nicaragua; and Ostional and Nancite, Costa Rica. In the Indian Ocean, it nests in great abundance in eastern India and Sri Lanka, although minor nesting also occurs at other localities. A small and declining population nests in the western Atlantic, primarily along the coasts of Surinam and French Guiana. It does not nest in the United States, but during feeding migrations, olive ridley turtles nesting in the Pacific may disperse into waters of the southwestern U.S., occasionally as far north as Oregon. The olive ridley is widely regarded as the most abundant sea turtle in the world because of the continued existence of several large arribadas. However, since its listing under the U.S. Endangered Species Act, there has been a decline in abundance of this species, and it has been recommended that the olive ridley in the western Atlantic be reclassified as Endangered. The need for this reclassification is based on continued direct and incidental take, particularly in shrimp trawl nets and nearshore gill nets. The western North Atlantic (Surinam, French Guiana, and Guyana) nesting population has declined more than 80 percent since 1967. Declines are also documented for Playa Nancite, Costa Rica; however, other nesting populations along the Pacific coast of Mexico and Costa Rica appear stable or increasing. In the Indian Ocean, Gahirmatha located in the Bhitarkanika Wildlife Sanctuary, India, supports perhaps one of the largest nesting populations in the world with an average of 398,000 females nesting in a given year. These populations, however, are suffering high mortality from nearshore gill nets and trawl fisheries. HABITAT: The olive ridley appear to be more of an open ocean inhabitant than its congener, the Kemp’s ridley, which primarily inhabits shallow nearshore coastal waters. CRITICAL HABITAT: None designated. REASONS FOR CURRENT STATUS: The decline of this species is primarily due to human activities, including the direct harvest of adults and eggs, incidental capture in commercial fisheries, and loss of nesting habitat. MANAGEMENT AND PROTECTION: In Mexico, 17 reserve areas were established for the protection of sea turtles in 1986, and a total prohibition on sea turtle harvest was instituted and additional protection camps were established on nesting beaches in 1990. Since the 1990 ban, the take of olive ridleys has been reduced, and the population appears to be stabilizing. U.S. and Mexico government regulations requiring shrimp trawlers to use turtle excluder devices have resulted in reduced mortality from commercial fishing operations in U.S. and Mexico waters. Continued direct and incidental take, particularly in shrimp trawl nets, remains a serious concern in the western Atlantic and Indian Oceans. 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