image: This shows the North Atlantic tracking routes of 17 juvenile loggerhead sea turtles. view more
Credit: Jiangang Luo - turtle track imagery Jim Abernethy - turtle photo
MIAMI – A new study satellite tracked 17 young loggerhead turtles in the Atlantic Ocean to better understand sea turtle nursery grounds and early habitat use during the 'lost years.' The study, conducted by a collaborative research team, including scientists from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, was the first long-term satellite tracking study of young turtles at sea.
"This is the first time we were able to show the maiden voyage of young turtles after they left the beach," said Rosenstiel School scientist Jiangang Luo and co-author of the study. "It's like you want to know how your baby is doing when you drop him or her off at the daycare for the first time."
The turtles' at-sea movements were remotely tracked for 27-220 days in the open ocean to better understand their movements, habitat preferences and thermal niche during this early-life stage. The turtles traveled between 200 km to 4300 km (124 - 2672 miles), mainly traveling off of the continental shelf region and occupying oceanic surface waters, where young turtles likely "receive thermal benefits from solar absorption," according to the study's authors. The study also showed that young sea turtles rarely travel into continental shelf waters and frequently leave the currents of the Gulf Stream and North Atlantic Current within the North Atlantic Subtropical Gyre.
The turtle started by riding in the strongest currents in the Ocean, the Gulf Stream, then, the North Atlantic Current. But many of the turtles took a short cut via eddies which span off from the currents to the Sargassum Sea at the center of the North Atlantic Subtropical Gyre, which provide protection, thermal and food habitat for the young turtles.
The 17 loggerhead turtles were collected from nests along the southeast coast of Florida and reared in Florida Atlantic University's turtle laboratory before being released between 3-9 months of age into the Gulf Stream, offshore of their natal beaches. Prior to being released, solar-powered satellite tags were affixed to the turtles' carapace.
"What is exciting is that we provide the first look at the early behavior and movements of young sea turtles in the wild," said University of Central Florida biologist and Rosenstiel School alumna Kate Mansfield, who led the team. "Before this study, most of the scientific information about the early life history of sea turtles was inferred through genetics studies, opportunistic sightings offshore, or laboratory-based studies. With real observations of turtles in their natural environment, we are able to examine and reevaluate existing hypotheses about the turtles' early life history. This knowledge may help managers provide better protection for these threatened and endangered species."
Once young turtles leave their nesting beaches they spend an unknown number of years at sea. Called the sea turtles 'lost years,' little is known about the migration and habitat use of young sea turtles during this period before they return to near-shore habitats as larger juveniles.
The study, titled "First satellite tracks of neonate sea turtles redefine the 'lost years' oceanic niche" was published in the DATE issue of the journal Proceedings of the Royal Academy B. The paper's co-authors include Kate Mansfield of the University of Central Florida and the National Marine Fisheries Service, Luo, Jeanette Wyneken of Florida Atlantic University and Warren P. Porter of the University of Wisconsin.
About the University of Miami's Rosenstiel School The University of Miami is one of the largest private research institutions in the southeastern United States. The University's mission is to provide quality education, attract and retain outstanding students, support the faculty and their research, and build an endowment for University initiatives. Founded in the 1940's, the Rosenstiel School of Marine & Atmospheric Science has grown into one of the world's premier marine and atmospheric research institutions. Offering dynamic interdisciplinary academics, the Rosenstiel School is dedicated to helping communities to better understand the planet, participating in the establishment of environmental policies, and aiding in the improvement of society and quality of life.
For more information, please visit: http://www.rsmas.miami.edu.