pheromone) function. Males resemble the females in size and coloration. Secondan.' sexual 

 characteristics of male sea turtles include a longer tail, more distal vent, recurved claws and. 

 during breeding, a softened mid-plastron. Eggs are 34-45 mm in diameter and 24-40 g in weight. 

 Hatchlings range from 42-48 mm in straight line carapace length. 32-44 mm in width and 15-20 

 g in weight. 



Post-hatchling Kemp's ridleys most likely associate with the sargassum community and feed on 

 associated infauna or other epipelagic species found in the Gulf of Mexico and Atlantic. Kemp's 

 ridleys become benthic feeders at approximately 2-0-25-cm carapace length when they return to 

 inshore and nearshore waters. Favored areas are seagrass beds or mud bottoms from Long Island 

 Sound to the Western Gulf of Mexico. Kemp's ridleys feed primarily on crabs. Age at sexual 

 maturity is not known, but recent estimates suggest that female Kemp's ridleys may reach 

 maturity within 11-12 years, although other estimates of age at maturity range from 12 to 35 

 years. Unlike sea turtles of other genera, Kemp's ridleys emerge synchronously during the day 

 to nest in aggregations called "arribadas" meaning "arrival" in Spanish. Nesting occurs between 

 April and mid-August and adult females lay an average of 3 nests per season. 



SPECIES DISTRIBUTION 



Kemp's ridleys occur mainly in coastal areas of the Gulf of Mexico and the northwestern 

 Atlantic Ocean. Adults of this species are usually confined to the Gulf of Mexico. Unlike most 

 sea turtles. Kemp's ridleys have a very restricted nesting range. The principal nesting beach is 

 located near Rancho Nuevo in the state of Tamaulipas, Mexico where 95% of the nests are laid 

 along 60 km of beach. Nesting also occurs sporadically at other beaches in Mexico and Texas, 

 and in recent years, there have been a few instances of Kemp's ridleys nesting on Florida's Gulf 

 and Atlantic coasts and on the coasts of North and South Carolina. 



MAJOR IMPACTS 



Impacts in the nesting environment 



Threats to the nesting beach in Mexico are presently few. but potentially serious. Human 

 population growth and increasing developmental pressure will result in increased threats to the 

 nesting beach. Only the central part of the prime nesting area is protected by Mexican 

 presidential decree. A primary concern is human encroachment and access along the entire 

 nesting area. However, the wording of the Mexican decree is vague and construction of 

 commercial fishing facilities proceeded in 1987 immediately adjacent to the main turtle camp at 

 Rancho Nuevo. Plans for development of La Pesca (just to the north of the nesting area) as a 

 fishing center and dredging of the Gulf Intracoastal Waterway from Brownsville. Texas to Barra 

 del Tordo (in the south part of the nesting beach) are under discussion. These plans are alarming 

 because of the assuredly detrimental and possibly disastrous effects that they could have on the 

 nesting population if they were to be carried out. 



A threat resulting from management practices at Ranch Nuevo is the relocation of all of the nests 

 in one corral to prevent poaching and predation. While this ensures the safety of nests from 

 poaching and animal predation. the concentration makes the eggs more susceptible to reduced 

 viability from manipulation, disease vectors, tidal inundation, and catastrophic loss. 



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