Meeting Abstract
P2.18 Wednesday, Jan. 5 The First Long Term Oceanic Tracks of Neonate Loggerhead Sea Turtles MANSFIELD, K.L.; WYNEKEN, J.*; Florida Atlantic University; Florida Atlantic University jwyneken@fau.edu
Neonate sea turtles undergo an oceanic migration that eventually takes them to distant nursery grounds, but how small turtles accomplish these journeys is unknown. Until recently, it has been impossible to track the movements of small sea turtles. Here we describe the movements of 7 neonate loggerhead turtles (Caretta caretta), tracked for 38 – 172 d, using small solar-powered satellite transmitters attached to each turtle’s carapace. All neonates were initially lab-reared for 127-281 d, and were 13-18 cm at release. Each had an acclimation period with the tag attached and then was released in the Gulf Stream Current, 18.5 km offshore from SE Florida. Tags transmitted for 38-172 d. The majority of Argos location class codes (LC) received from the tags were of high location accuracy, (>65% LC 1-3), likely reflecting the surface-based behavior of the young turtles. The turtles usually remained within or in close proximity to the Gulf Stream as they moved northward up to 13° in latitude and westward up to 20° in longitude. One turtle departed from the Gulf Stream, moving to the waters adjacent to Bermuda where it remained for 2 mo before traveling toward the Gulf Stream. The turtles associated with frontal systems, including the Gulf Stream’s western and eastern boundaries, and with meso-scale eddies. Satellite sea surface data indicate our turtles selected surface waters > 17° C; tag sensor data indicated warming ±2-3° above available sea temperatures, suggesting the turtles were basking or surface dwelling. Turtles varied in movements, even when released on the same day. The turtles did not select the fastest routes to nursery areas in the eastern Atlantic but may have selected routes that exposed them to the richest resources. This study provides the first field evidence that neonate turtles are more than passive drifters.
