NMFS-PIFSC Turtle Tracking

These data together with environmental data from satellite remote sensing are used to describe the oceanic habitat used by these turtles. The results indicate that loggerheads travel westward, move seasonally north and south primarily through the region 28-40 deg N, and occupy sea surface temperatures (SST) of 15-25 deg C. Their dive depth distribution indicated that they spend 40% of their time at the surface and 90% of their time at depths <40 m.

Loggerheads are found in association with fronts, eddies, and geostrophic currents. Specifically, the Transition Zone Chlorophyll Front (TZCF) and the southern edge of the Kuroshio Extension Current (KEC) appear to be important forage and migration habitats for loggerheads. In contrast, olive ridleys were found primarily south of loggerhead habitat in the region 8-31 deg N latitude, occupying warmer water with SSTs of 23- 28 deg C. They have a deeper dive pattern than loggerheads, spending only 20% of their time at the surface and 60% shallower than 40 m.