Fig 1.
von Mises probability density function.
The density is plotted for μ = 0 and different values of the concentration parameter κ.
Fig 2.
Thermal habitat suitability index as a function of water temperature.
Fig 3.
Evolution with age of the lower pivotal water temperatures T1 andT2, and the minimum tolerated temperature (Tmin) defined by GAL.
Fig 4.
Thermal habitat suitability index as a function of water temperature for leatherbacks of different ages.
Fig 5.
Normalized rate of food consumption F0(a)as a function of age.
Fig 6.
Simulated 18-year long trajectories of (a) passive and (b) active leatherbacks dispersing in the North Pacific.
Individuals are released offshore Jamursba-Medi nesting beach (white dot on the map). The color along each track evolves with the age of the simulated turtle.
Fig 7.
Maps of habitat suitability index.
Maps for 1- and 9-year-old leatherbacks during winter (January to March) and summer (July to September).
Fig 8.
Schematic map of surface currents in the North Pacific.
NECC: North Equatorial Countercurrent; NEC: North Equatorial Current; HE Halmahera Eddy; ME: Mindanao Eddy; KEC: Kuroshio Extension Current; NPC: North Pacific Current; NPTZ: North Pacific Transition Zone. Underlying current speeds are those of the G1 ocean reanalysis on October 1st, 2002.
Fig 9.
Cumulative cold-induced mortality in passive and active turtles.
Fig 10.
Spatial distribution of cold-induced death events in passive (a) and active (b) turtles.
Fig 11.
Link between cold-induced mortality and initial dispersal pathway.
Cold-induced mortality rate and mean age (±1 std) when reaching 30°N in active turtles pooled as a function of the easternmost longitude reached in the NECC (south of 10°N).
Fig 12.
Histogram of the North Pacific crossing times (PCT) for (a) passive and (b) active turtles.
Fig 13.
Mean latitude as a function of simulation time for groups of (a) passive and (b) active turtles with the same PCT.
A group with a crossing time of N years is actually made of all turtles having a crossing time between N years– 6 months and N years + 6 months.
Fig 14.
Circular histogram of the daily swimming velocities.
This histogram includes the daily swimming velocities of all active turtles found between 120°E and 140°W and north of 25°N. The color in each 10°-wide heading bin reflects the number of daily swimming velocities found in this bin. This number is normalized so that the most populated bin has an index of 100.
Fig 15.
Zonal variations in habitats and speeds.
Averaged longitudinal variations of (a) habitat suitability indices (h, hT, hF) and (b) zonal speeds (us, uc, ug) along the trajectories of active turtles crossing the North Pacific.
Fig 16.
Number of turtle days in 1°x1° boxes for (a) the passive and (b) the active dispersal simulations.
Fig 17.
Mean value of the NPP encountered by active turtles crossing the Pacific alive.
The food requirement curve F(a) is that of individuals born at the peak of the emergence period, that is on September 15 of the first simulated year. Tags with the mean longitude of the simulated turtles are inserted at various simulation times to establish the link between the position and simulation time.