As It Happens

Scientists have solved the mystery of where baby sea turtles go after they hatch

After green sea turtles hatch, they scuttle across the sand, jump in the Atlantic ocean and disappear into the horizon. Scientists have never really known where the sea turtles spend the next few years of their life. But biologist Kate Mansfield now has a pretty good idea.

The critters spend their early years in a 'warm, safe and food-filled habitat,' study finds

A baby green sea turtle is pictured swimming amongst the protective algae of the Sargasso Sea. Tracking young green sea turtles with solar-powered satellite tags helped scientists learn more about the animals' 'lost years.' (Gustavo Stahel/University of Central Florida Marine Turtle Research Group/Permit number NMFS - 19508)

Read Story Transcript

It turns out baby green sea turtles don't just drift aimlessly on an Atlantic Ocean current — they're bound for the warm algae oasis of the Sargasso Sea. 

After green sea turtles hatch from the eggs buried in the warm sands of Atlantic U.S. beaches, they head into the ocean waters, where their whereabouts have remained unknown to scientists until the turtles reach adulthood.  

The majority of sea turtle species have these so-called "lost years," according to Kate Mansfield, an associate professor of biology at the University of Central Florida. Mansfield is the lead author of a new study that sheds light on the green sea turtles' lost years. 

"Those are the foundational years for these animals," she told As It Happens host Carol Off. 

"If we're working with these endangered and threatened animals, we need to know this information, so we can better plan for conservation efforts and policies to help protect them."

In previous research, biologist Kate Mansfield and her team used satellite trackers on loggerhead turtles, seen above, in a technique that paved way for the green sea turtle study. (Kate Mansfield, UCF MTRG / Permit number NMFS - 19508)

For the study, published in The Proceedings of the Royal Society B earlier this month, Mansfield and her team used satellites to track the baby turtles' movement from nesting beaches in the eastern coastal U.S. into the ocean.

The turtles have led the researchers to the Sargasso Sea, a body of water in the North Atlantic ocean that, unlike all other seas, does not have a land border and is instead contained within several ocean currents. Mansfield says the turtles likely choose this unique destination for its namesake, the Sargassum algae, which provides them with "a warm, safe and food-filled habitat." 

Young turtles can perch up on the floating algae, which conceals them from visual predators, the biologist said. The brown algae also attracts light and traps water, keeping the turtles warm. 

"For a cold-blooded animal that needs to grow quickly and outgrow the jaws of sharks and other predators, it's a pretty good place for them to grow up," Mansfield said. 

A young sea turtle is pictured nestled in brown Sargassum algae. Mansfield says the colour hides the creatures from predators. (Chris Long/UCF MTRG/Permit number NMFS - 19508)

The biologist says she has seen an increase in the numbers of nests along the coast of Florida — a good sign for the population of young turtles. But she says it still takes about 25 years for turtles to reach maturity in order to nest and breed. This is why the knowledge of the turtles' habitat during the in-between years is so important. 

"If we can better target those early years and know how we can protect them, we give them a better chance down the road to be able to reach maturity and hopefully contribute back to their population and have their population grow."


Written by Olsy Sorokina. Interview with Katherine Mansfield produced by Sarah Jackson.

Add some “good” to your morning and evening.

Get the CBC Radio newsletter. We'll send you a weekly roundup of the best CBC Radio programming every Friday.

...

The next issue of Radio One newsletter will soon be in your inbox.

Discover all CBC newsletters in the Subscription Centre.opens new window

This site is protected by reCAPTCHA and the Google Privacy Policy and Google Terms of Service apply.