At the turn of the millennium, the origin of leatherback turtles in California waters was unproven. Many assumed they originated from nesting beaches in Mexico or Costa Rica; few could have imagined the extent of their travels across the entire Pacific Ocean. We know now that West Pacific leatherbacks only make their epic trans-Pacific migration about every three to five years. Unfortunately, the batteries on early satellite tags didn’t last long enough to track their whole migration.
The Arrival
Arribada roughly translates to “arrival”, but in so many ways, it’s an understatement. Turtle nesting on Ostional Beach occurs year-round, but hits a peak in the rainy season between August and November. Each month on the last quarter of the full moon, olive ridley sea turtles gather off the coast of Ostional and prepare to lay their eggs en masse. The mass nesting of the arribada corresponds with the evening high tide, and for a few nights each month hundreds to thousands of sea turtles emerge from the sea to lay their eggs.