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Introduction Sea Turtles of the Californias
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Sea Turtle Conservation Network of the CaliforniasSea Turtle Species of BajaFive species of sea turtle are known to inhabit Californian waters - which provide important foraging and developmental areas for turtles from as far away as Japan and southern Mexico - and all five species are considered endangered or threatened.
East Pacific Green Turtle Most east Pacific green turtles found in Californian waters are born on beaches in southern Mexico, specifically Colola and Maruata, Michoacan. Juvenile and adult turtles can be found from San Diego along virtually the entire length of the Baja California peninsula in bays and estuaries, both in the Gulf of California and Pacific Ocean. The distinctive color and shape of this population of the world ranging green led to the belief that it was a separate species. Genetic analysis suggests that the black turtle is most likely a subspecies. This species is predominantly coastal, feeding primarily on benthic algae and sea grass as well as the occasional invertebrate animal - such as crabs, seapens and tunicates. Individuals are thought to hibernate for weeks without taking a breath in the cold winter water of the Gulf of California. East Pacific green turtles were once harvested indiscriminately by the thousands leading to a crash in this population. Now, they are still caught illegally for food and accidentally in many different types of nets. Some of the tracks of black turtles we have monitored in Baja California can be seen at: http://www.cccturtle.org/sat21.htm
Born on beaches in Japan, loggerheads found along the Californian coast have traveled on the currents more than 12,000 km across the Pacific Ocean. When they arrive in the Californias, after 2-6 years at sea, they feed on the abundant red crabs (Pleuroncodes planipes) and grow. Loggerhead turtles may pass near the coast or even enter the Gulf of California. However they are usually found offshore in deep pelagic waters. At maturity loggerhead turtles return to their natal beaches to reproduce and the cycle begins again. Unfortunately, many turtles are caught in nets and on hooks before they complete this amazing journey. One loggerhead turtle named Adelita, the first that we tracked from Baja California to Japan, appears to have died only a few kilometers from her destination in Japan: http://www.turtles.org/adelita.htm.
This species typically nests in mass numbers called "arribadas". The Mexican Pacific population is recovering and the ridley is the most abundant sea turtle species in the eastern Pacific. In Baja California this species nests in the cape region and is one of only two species that regularly nest on the peninsula, the other is the leatherback. In the water, olive ridleys are usually found basking offshore. Their preferred food is the abundant pelagic red crab.
Tortuga carey, Eretmochelys imbricata. The trade in souvenirs made from its beautifully patterned shell contributes to the endangerment of this species. Hawksbill shells can still be found adorning the walls of homes and cantinas throughout Baja California. In southern Baja California waters, particularly in the vicinity of La Paz, this species was once abundant. Now they are very rare. Nesting hawksbills are only encountered sporadically along the Mexico's Pacific coast. This species eats primarily sponges and other invertebrates.
Satellite transmitters reveal this species roams throughout the world's oceans and is a warm bodied deep diver. The combination of egg poaching and bycatch in driftnets and on longlines has resulted in a sharp decline in Pacific populations. The nesting beaches in Baja California, near Todos Santos, where this species nests have emerged as important sites for the recovery of the species. However, they are at the extreme north end of the species nesting range and the viability of eggs is questionable - perhaps related to high temperatures and low humidity in the region. Leatherback turtles feed on jellyfish and travel all over the Pacific when they are not on Baja California beaches. Encounters are frequent in the Monterey Bay, California area. The Monterrey leatherback turtles come from Indonesian beaches to feed on California's abundant jellies. These animals truly connect the entire Pacific Ocean. More sea turtle photos can be found at: http://www.seaturtle.org/imagelib/ and |
Loggerhead Turtle
Olive Ridley
Leatherback Turtle