Against the Odds, A Kemp's Ridley Story

There are only seven species of sea turtle in the world, five of which have ranges in the Gulf of Mexico and the Atlantic Ocean. Each one is threatened to varying degrees, but the smallest of them, the Kemp's ridley, is critically endangered. Kemp's ridleys (like other sea turtles) evolved to cope with threats from predators. Their strategy, though, was no match for humans in the latter half of the 20th century. Their tale could have easily ended in extinction had it not been for crucial discoveries and targeted environmental actions that happened just in time.

Adversity from the Start

Life for a baby Kemp's ridley begins in the dark of a warm, sandy nest, most often located on a beach between the Rancho Nuevo region of Mexico and Padre Island in Texas. Its mother will have hauled herself onto that white sand, dug her nest, and laid around 100 eggs before burying them all and returning to the ocean. She may repeat this two or three more times before the breeding season ends. With survival odds as low as one in 10,000, she is fortunate to have reached adulthood. Now, her offspring will take their chances.

Reclusive Juveniles

Once young Kemp's ridleys enter the water, they seemingly disappear in the ocean's vastness. For decades, scientists were unsure where these hatchlings and juveniles went. Although researchers today better understand where the turtles go, there are still unanswered questions. Since it takes two to ten years for these juveniles to return to coastal waters, answering these questions can better protect them while they are out at sea.

While this juvenile female remains in the Gulf, others do not. Life can take a few different turns for the 5% to 30% of hatchlings and juveniles caught in the Gulf Stream. These Kemp's ridleys have been seen around the North Atlantic Ocean from waters off New England and Nova Scotia, with a few carried as far as the Azores over 3,000 miles away! The Sargasso Sea, a huge swath of ocean surrounding Bermuda, is believed to host many of these turtles since clumps of sargassum persist year-round there.

Navigating Adulthood

After a few years, this juvenile has grown large enough to leave her pelagic lifestyle behind. She, like others around her age, gradually starts moving toward shallower water and hunting for prey associated with the seabed, like crabs. Shallower water (less than 200 feet deep) means these turtles enter coastal regions around the Gulf of Mexico or along the East Coast, where other threats await them.

Historically, the arribada was perhaps the starkest evidence of how much the Kemp's ridley population struggled. The turtles' primary nesting beaches had largely remained a mystery until the 1960s when researchers came across video footage from 1947, filmed by nature enthusiast Andreas Herrera. He had spotted females coming onshore en masse along a remote stretch of beach near Rancho Nuevo, Mexico. By some estimates, his videos showed as many as 27,000 individual female Kemp's ridleys at a time.

In subsequent years, though, when researchers began surveying the same beach, they found far fewer turtles. Two factors driving the population's decline became apparent. First, increased fishing around the Gulf meant more turtles were injured or died from entanglement in nets and gear. Second, people were actively harvesting adult turtles and eggs for food during nesting season. This combination was incredibly detrimental, given the already high mortality rate of hatchlings, and how crucial each adult was to sustain the next generation. Scientists and conservationists sounded the alarm and by the 1970s, Mexican and U.S. agencies were collaborating to save the turtles. Significant damage had been done, though, and by the mid-1980s, fewer than 300 females came to nest on those sandy stretches.

Rescue and Ongoing Recovery

Legal protections, bans on egg and turtle harvesting, and the design and requirement of turtle excluder devices in U.S. fisheries were lifelines the Kemp's ridleys needed, although they nearly came too late. From the 1990s to the late 2000s, the Kemp's ridley population steadily grew, with a few thousand females returning to beaches in Mexico each year. Currently, it's estimated over 5,000 females are laying nests annually, with new nesting beaches established further away from Rancho Nuevo.

Today, Kemp's ridley's exponential population growth has stalled, though, leading scientists to consider coastal development and the aftermath of events like the 2010 Deepwater Horizon oil spill as factors in their continued decline. There is also the question of the turtles that are swept into the Atlantic. How many of them make it back to the Gulf and their nesting beaches? Kemp's ridleys still keep secrets, it seems.

Kemp's ridleys may be less of a mystery than they once were, but they still need our help. National Aquarium Animal Rescue is dedicated to sea turtle rescue, rehabilitation and release, and routinely cares for dozens of stranded cold-stunned or injured Kemp's ridleys. There are many individual and group actions people can take, too, from participating in beach cleanups to urging Congress to support the Sea Turtle Rescue Assistance and Rehabilitation Act and other legislation. Despite the odds, helping save even one Kemp's ridley can do a world of good for their species.