Leatherback sea turtles in the Pacific Ocean are in far greater danger of extinction than the Atlantic Ocean populations due to greater commercial fishing, illegal poaching, ocean pollution, and nesting beach destruction in the Pacific. Leatherbacks in the Pacific can be divided into two primary populations, those that nest in the Eastern Pacific and those that nest in the Western Pacific.

Eastern Pacific Leatherback Sea Turtles. Leatherbacks in the Eastern Pacific population primarily nest in Central America and spend most of their lives offshore of nesting beaches or migrating to foraging areas. The nesting population at Playa Grande, Costa Rica numbered in the thousands in the 1980s and has now dipped below two hundred in a perilous dive towards extirpation. The largest foraging area is offshore of Chile, in the southeastern Pacific. The corridor above the Cocos Ridge of seamounts is a migration area of critical importance to many species between Cocos Island and Easter Island. However, some nesting occurs in Mexico and foraging leatherbacks from the Eastern Pacific population may venture into California waters to feed.

Western Pacific Sea Turtles. Nesting of Western Pacific Sea Turtles occurs along the beaches of Indonesia, Papua, Papua New Guinea, Malaysia and many other areas in the proximity that are still being reported. These leatherbacks can migrate to feed offshore of Australia but many make an amazing voyage across over 6,000 miles of the Pacific to feed on dense aggregations of jellyfish along the West Coast of the U.S.

Amazing Facts About Leatherbacks (PDF fact sheet):
• Leatherbacks are “living dinosaurs,” having survived 100 million years virtually unchanged.
• Adult leatherbacks can grow to over 8 feet long and weight up to 2,000 lbs.
• When feeding, leatherbacks can dive more than 2,000 feet below the ocean.
• Their journey to the U.S. West coast to feed on jellyfish and back to nesting beaches can be more than 13,000 miles!
Pacific Leatherback Threats
• Up to 50 percent of the remaining Pacific leatherbacks are caught each year by longline fishermen (2). Many are killed and even more are injured and then released without care.
• In 2000, pelagic longlines in the Pacific killed an estimated 1,000-3,200 leatherbacks (2).
• Accidentally eating plastic pollution is common for leatherbacks, and can result in nutritional loss and even death (4).
Additional threats to leatherbacks come from capture in gillnet fisheries, vessel strikes, poaching, coastal pollution, entanglement in abandoned fishing gear, and nesting beach habitat destruction.
Scientific Findings and Predictions
• Pacific leatherback populations have declined by approximately 90 percent in the last 25 years (2).
• Unless current fishing practices are changed, Pacific leatherbacks will be extinct in as little as 10-30 years (2).
• The death of more than 1 percent of the adult female Pacific leatherback population each year could lead to its extinction (3).
Protections Enacted in California’s Oceans
• In 1990, the California State Legislature banned all longline fishing in the Exclusive Economic Zone (EEZ) to prevent the deaths of leatherbacks sea turtles (5).
• In 2008, the California Legislature passed Assembly Joint Resolution No. 62 (Leno) for west coast sea turtle protection, supporting efforts to preserve and recover Pacific leatherback populations.
Pacific Ocean Leatherback Protections
• Sea Turtle Restoration Project’s (STRP) work resulted in the National Marine Fisheries Service establishing critical habitat for the leatherback within much of the California, Oregon, and Washington EEZ.
• STRP established the Leatherback Conservation Area, a large, closed area for the deadly California drift gillnet fishery to protect leatherbacks during their feeding season.
• STRP successfully closed the Hawaiian longline fishery for its deadly impacts to Pacific leatherback and loggerhead sea turtles in 2006, allowing it to re-open only after more protections were in place.
• Ongoing STRP work has continued to make it illegal for longline vessels to fish in any U.S. EEZ Pacific ocean territory along California, Oregon, and Washington.
References
(1) Benson SR, et al., 2007. Abundance, distribution, and habitat of leatherback turtles (Dermochelys coriacea) off California, 1990-2003. Fish Bull. 105:337-347.
 (2) Lewison et al. 2004. Quantifying the effects of fisheries on threatened species: the impact of pelagic longlines on logger head and leatherback sea turtles. Ecology Letters 226.
(3) Spotila et al. 1996. Worldwide population decline of Dermochelys coriacea: are leatherbacks going extinct? Chelonian Conservation Biology 2:209-222.
(4) Mrosovsky et al. (2009). Leatherback turtles: The menace of plastic, Marine Pollution Bulletin 58: 287–289.
(5) NMFS. Draft Environmental Assessment, 2007. Issuance of Exempted Fishing Permit to Fish with Longline Gear in West Coast EEZ, 2007.