Kemp's Ridley Migration: a Long and Dangerous Journey

Ultimately, the hatchlings will grow into adults that will return to South Padre Island to lay the next generation. This Kemp's ridley laid nest 8 on May 23, 2014. Brad Daddles photo.

Ultimately, the hatchlings will grow into adults that will return to South Padre Island to lay the next generation. This Kemp's ridley laid nest 8 on May 23, 2014. Brad Daddles photo.

By Theresa Madrigal
On July 4th Sea Turtle, Inc. had its first public hatchling release of the 2014 nesting season. Those of you watching on the beach or on our new hatchling webcam witnessed 110 Kemp’s ridley hatchlings start the first part of their incredible journey. Staff, interns, and volunteers ensured the hatchlings made it safely to the water.
What happens to those babies afterwards? Do they find their moms and dads like Crush says in Finding Nemo? The answer is actually no. The hatchlings face this long and dangerous journey by themselves.
The Bi-National Recovery Plan for the Kemp’s ridley sea turtle — put in place by various agencies in the United States and Mexico — heavily researched the migration patterns of this species. Upon reaching the water, the Kemp’s Ridley hatchlings swim for 20 to 30 hours offshore running on the energy stores provided from their yolk sacs. They then spend several years floating in the sargassum, a type of seaweed. This brown macroalgae provides a safe place for them to develop and the currents carry them eastward. Some of these hatchlings remain in the Gulf of Mexico and some are carried up the Gulf Stream and into the Atlantic Ocean. Juvenile Kemp's remain in the open ocean for an average of two years before they move into more coastal waters. They also use a variety of coastal foraging grounds and deeper ocean habitats.
As juveniles, Kemp’s ridley hatchlings have been found as far north as Massachusetts. Being so far north during cold months puts them at high risk for cold-stunning, another term for hypothermia. Since sea turtles are reptiles, their body temperature regulates with the environment. The National Oceanic and Atmospheric Administration has studied cold-stunning in sea turtles. Their website explains that when the turtles are exposed to prolonged cold-water temperatures, they become hypothermic, which can result in decreased heart rate and circulation and lethargy. Severe cases progress to shock, pneumonia and death.

90 Kemp's ridley turtles fight their way to the ocean on the morning of July 8. The odds are tough for the Kemp's ridley. Only one to three in 1000 will live long enough to return to the Texas beaches to nest. Teresa Shumaker photo.

90 Kemp's ridley turtles fight their way to the ocean on the morning of July 8. The odds are tough for the Kemp's ridley. Only one to three in 1000 will live long enough to return to the Texas beaches to nest. Teresa Shumaker photo.

A study conducted by Brett Still, Curtice Griffin and Robert Prescott at the University of Massachusetts Amherst found Kemp’s Ridley sea turtles most frequently cold-strand in Cape Cod Bay during the month of November. The air temperature during these times was below 51 degrees Fahrenheit and the winds were over 12 mph. The New England Aquarium in Boston operates a sea turtle rescue and rehabilitation facility in Quincy, MA. Currently they have seven Kemp’s ridley juveniles that stranded during the winter of 2013. Once these turtles are healthy, they will be released off the coast of Florida.
The Bi-National Recovery Plan for the Kemp’s ridley states that the adults are primarily found only in the Gulf of Mexico. Here they feast on crabs, their favorite food. They reach maturity around the age of 12. At this point, their carapaces are around 2-feet in length and weigh near 100 pounds. This is when the lifecycle of the Kemp’s ridley sea turtle starts again as the adults mate and nest.
Adult sea turtles will always return to the same beaches where they hatched to lay their eggs. Females generally nest every other year and will lay two to three clutches per season with about 100 eggs per clutch. Once they have laid their eggs, the females will return to the Gulf of Mexico until it is time to mate and nest again. In the meantime, their babies grow under the sand until they are ready to start their own journey.
The sad truth is that many of the hatchlings released on July 4th will not make it to complete this lifecycle. It is estimated that 1 in 1000 hatchlings from unprotected nests will live long enough to reproduce as an adult. This is because they must face the gauntlet of predators, pollution, and human interference. The good news is that our efforts here at Sea Turtle, Inc. and in Mexico have increased the odds to 3 in 1000 hatchlings! Currently our hatching success rate for this season is at an incredible 92%! It is our hope that these babies will be back in 12 years to reproduce and we will be here patiently waiting for them.
*Special thanks to Dr. Charles Innis and Tina Wilkins from the New England Aquarium for their correspondence and information!
Theresa Madrigal wrote this article while interning for Sea Turtle, Inc. last summer. She graduated from Fitchburg State University in Massachusetts in December 2013 with a Bachelor’s degree in Biology, a concentration in Environmental Biology, and a minor in Chemistry. She is originally from Leominster, MA and volunteered at the New England Aquarium in Boston for eight months from 2010-2011.