The Ridley in the Library with the Candlestick, right?

Did you know that the Kemp’s ridley sea turtle was at one time considered the most mysterious turtle of the Gulf coast?  According to prominent sea turtle naturalist Archie Carr, the ridley was maddeningly perplexing.  Recently I have been reading Dr. Carr’s accounts of his experiences searching for sea turtles throughout the Gulf coast and Caribbean during the 1940s in his book, The Windward Road.  This book immediately starts with the question of the origin of the ridley.  Kemp’s ridley was thought to be a bastard turtle, a kind of hybrid created from the joining of a loggerhead and a green.  This theory came about because by all accounts of local Caribbean fishermen and biologists, the ridley had never been seen coming onto the beach to nest anywhere.  Dr. Carr did not accept this explanation so easily though because he thought of the ridley as a distinct creature with its own traits.

Therefore, he considered the possibility that the Kemp’s nested in some remote area in the Caribbean or somewhere completely far off.  However, throughout his travels all around the Caribbean, Dr. Carr never came across the ridley or a turtle hunter who knew of the ridley.  Maybe the ridley really did nest at the same time and in the same places as other species, as five reports stated, but after being investigated by Dr. Carr, this idea was proved false.  Perhaps Kemp’s were giving birth to live young at sea?  Seemed unlikely considering that the other four species of sea turtles nest along beaches and deposit eggs.  Dr. Carr also discounted the idea that the ridley laid its eggs at sea because salt water would eventually destroy the egg.  A more plausible theory is that Kemp’s ridley simply has a very specific breeding season and maybe comes ashore at an odd time.  This makes sense except for the fact that never before had anyone reported catching a pregnant female.  So not only has no one ever reported seeing Kemp’s coming ashore to nest but no one has even caught a pregnant female in the wild.

Can you see how a biologist might go insane?  Oh, and did I mention that the Pacific ridleys had been well documented coming ashore to lay eggs? Apparently this phenomenon was only occurring in the Gulf of Mexico and along the Atlantic coast.  Therefore, Dr. Carr ultimately proposed that Kemp’s ridley must nest along a very specific stretch of shoreline that had not been searched yet and had a particular migration pattern that kept pregnant females hidden.

Don’t forget that this mystery was taking place during the 1940s and has since been solved. Actually the question was answered in 1947 when a Mexican farmer shot some footage of more than 40,000 Kemp’s ridleys coming ashore to nest.  However, the farmer did not realize the significance of his discovery and thus his footage remained private for 15 years!  It was not until 1962 did Archie Carr, who was still searching for a ridley nesting site, finally see this footage.  During a very specific few days in June, large masses of females come ashore along a 90 mile stretch in Rancho Nuevo, Mexico.  And just like that…the mystery was solved!

Sources
Carr, Archie. 1979. The Windward Road: Adventures of a Naturalist on Remote Caribbean Shores. University Press of Florida: pgs. 5-29.
Safina, Carl and Bryan Wallace. Solving the ‘Ridley Riddle’. http://seaturtlestatus.org/sites/swot/files/SWOT5_p26_Ridleys.pdf.

Posted by Kirstie B.
Kirstie is a Spring, 2014 Intern at the National Marine Life Center. She recently graduated from Smith College with a major in Biology.