In Baja California Sur, there are five species of sea turtles.  Of these species, the loggerhead turtle (Caretta caretta) and hawksbill (Eretmochelys imbricata) only visit the coasts to forage. The other three species, the olive ridley turtle (Lepidochelys olivacea) nests regularly while the leatherback turtle (Dermochelys coriacea) and the black turtle (Chelonia mydas agassizi) do so sporadically.

The olive ridley turtle (Lepidochelys olivacea) belongs to the Cheloniidae family and is the smallest of the species that make up this family. In Mexico, nesting is distributed mainly in the lower part of the Peninsula: from Bahía Magdalena to the south, both in the Pacific and in the Gulf of California. Females nest on the coasts of Baja California Sur, in the months of July-November although incidental nesting occurs all year long. Its carapace is gray – olive and can measure up to 78 cm. This species is currently listed as Endangered in Mexico.

The leatherback turtle (Dermochelys coriacea) is the largest sea turtle species in the world. It does not have a hard shell like the others, since it belongs to different family (Dermochelyidae). In Mexico nesting is distributed mainly in Michoacán, Guerrero and Oaxaca. Its shell can reach up to 175 cm and weigh up to 500 kilograms. Its nesting season in the Eastern Pacific is from October – April. Currently, this species is considered critically endangered in the Eastern Pacific, thus the nesting of this species on the coasts of Baja California Sur is very scarce.

The black turtle (Chelonia mydas agassizi) is distributed throughout the eastern Pacific, being common from the center of the Peninsula of Baja California and the Gulf of California, to the north of Peru. In Mexico, it nests mainly in Michoacán. Its carapace is dark in color and can measure a curved carapace length of up to 90 cm. They come to spawn to the coasts of Baja California Sur sporadically, since their main nesting areas are in Colola and Maruata (Michoacan) and Isla Clarion and Socorro in the Revillagigedo Islands. It is currently in danger of extinction.

Guía Ilustrada de la Tortuga Marina en B.C.S.
by Patricia Baum