Sea Turtle Swims Into History: Migrates from Cocos Island National Park to the Galapagos

Sanjay, a 117-pound male, Pacific green sea turtle made history when he swam from the protected water of Cocos Island Marine National Park in Costa Rica and crossed into the Galapagos Marine Reserve in Ecuador. Sanjay is the first sea turtle to corroborate preliminary genetic data suggesting many of the resident sea turtles at Cocos Island were born on the nesting beaches of the Galapagos Islands located 400 miles south.

Sanjay was one of three endangered green sea turtles (also known as Eastern Pacific black turtles) tagged in June with satellite transmitters by researchers at Cocos Island, Costa Rica during a Turtle Island Restoration Network and PRETOMA expedition to elucidate sea turtle and shark migration routes and their use of marine protected areas.

Sanjay was tagged by Turtle Island Restoration Network & PRETOMA on a joint research expedition.
Sanjay was tagged by Turtle Island Restoration Network & PRETOMA on a joint research expedition.

Sanjay’s 14-day swim is significant to the scientific community because it confirms another direct ecological connection between these two protected marine areas and adds another significant piece of evidence suggesting an important migratory ‘superhighway’ between the Cocos Islands and the Galapagos for a number of species including several threatened shark and turtle species.

Insight like this is exciting and helps us understand species behavior, but it also is critically important to successfully protecting endangered marine species in the face of threats from intense industrial fishing including longline vessels that place tens of millions of hooks in the Pacific each year.  While Sanjay is protected in the relatively small marine sanctuaries that surround these internationally recognized marine island gems, sea turtles and sharks fall victim to fishing hooks and nets as they attempt to migrate between these safe havens.

To this end Turtle Island Restoration Network and partner organizations have tagged 101 sea turtles at Cocos Island (24 with satellite transmitters and 46 with acoustic tags) since 2009. Our joint research program is documenting how endangered sea turtles and sharks use Cocos Island and Galapagos National Park marine protected areas in order to understand the biological connectivity between these two sanctuaries.  Sanjay, the sea turtle, joins several hammerhead sharks, a silky shark, and a Galapagos shark that have been proven to spend time at both of these reserves.

Sanjay's Migration Path
Map of Sanjay’s migration route from the Cocos Islands to the Galapagos Islands.

Evidence now shows that a swimway between the Cocos Islands and the Galapagos Islands is being used as a migratory path for several protected species. We are now suggesting to the governments of Costa Rica and Ecuador that they link these two international marine biosphere reserves by creating a protected swimway that offers safe passage to these migratory species.

If you’d like to find out where in the great blue ocean Sanjay is friend us on Facebook and follow the hashtag #GoSanjay on Twitter. Recent pings suggest that Sanjay is on the move and headed to turtle nesting grounds at Isabela Island. Bon Voyage Sanjay!  If you are an experienced scuba diver and would like to join a future expedition to Cocos Island as a citizen scientist, visit and check out the News Watch blog

Human Journey


Meet the Author
Todd Steiner is the founder and executive director of Turtle Island Restoration Network. Previously, he was director of the Tuna Dolphin project, which was responsible for bringing to public view the tuna industry’s impact on dolphins and other marine species. He has more than 30 years experience in environmental protection and education. He serves on the Advisory Board of the Cordell Bank National Marine Sanctuary. He holds an MS in Biology and lives in Forest Knolls, Calif.