Tracking Devices on Young Sea Turtles Reveal Turtles' Movements During 'Lost Years'

Tracking instruments that were placed on the shells of young sea turtles have given scientists answers about where sea turtles go when they travel out to sea.

A University of Central Florida biology professor glued a small tracking instrument--which cost $4,000 each---onto the shells of 17 young sea turtles that were released in groups from 2009 to 2011.

According to the Orlando Sentinel, Professor Kate Mansfield and a team of other researchers discovered that young loggerhead turtles go into a remote area of the ocean, the Sargasso Sea, where they spend years eating, lounging and growing up among piles of sargassum seaweed.

Previously, researchers assumed that the endangered species rode the whirlpool that circles around the Atlantic.

"It turns out the turtle tracks are a lot more variable than just following this big doughnut around the ocean," Mansfield said. "Sargassum provides them with refuge. The turtles are brown, and they blend really well with that habitat, and there are a number of little organisms [crabs and fish] that turtles might eat."

Florida has some of the most important beaches in the world for loggerhead nesting. The state has worked for decades to document and protect their nests, and to minimize bright lights, which can disorient turtles' journey into the sea.

"So one of the questions is: 'OK, if a hatchling sees a light and goes the wrong way for a little while, how does that affect their incredible journey offshore?'" said Robbin Trindell, sea-turtle-program leader at the Florida Fish and Wildlife Conservation Commission.

"The more we understand about what they do offshore, the more we can understand how important it is to limit impacts to them during that short time we have them under our care on the beach," Trindell said.

Professor Mansfield and her colleagues got help from a manicurist with the project, who suggested using a nontoxic, acrylic coating because turtle shells are composed out of the same material as fingernails. With the coating as a foundation on the shell, researchers glued down a piece of old wetsuit as bedding for the device, which is attached with hair-extension glue because it is waterproof and flexible.

The trackers send a signal to satellites that include the turtle's location, temperature and how much power is being produced by solar chargers.

The turtles were followed from 27 to 220 days before the devices fell off the shells.

Researchers were then able to gain some insight into what are called the "lost years" of loggerhead turtles.

"We're getting a look at the toddler-to-teenage stage," Mansfield said.