Solvin Zankl / Mature female Olive ridley sea turtles (Lepidochelys olivacea) arriving on the beach of Ostional, Costa Rica, Pacific coast, during an arribada / mass nesting event, November

Solvin Zankl / The arrival of many Olive ridley sea turtles (Lepidochelys olivacea) at the beach of Ostional, Costa Rica, Pacific coast, at the beginning of an arribada (mass nesting event) November ^^^ Thousands an...

Solvin Zankl / Female Olive ridley sea turtle (Lepidochelys olivacea) swimming from the open ocean towards the beach of Ostional, Costa Rica, Pacific Ocean to lay its eggs in the warm sand, November

Solvin Zankl / A Costa Rican researcher monitors the temperature in the developing sea turtle nests at Ostional beach, Costa Rica, November 2009. ^^^ Sea turtles have, like many other reptiles, temperature-dependent...

Solvin Zankl / These hatchlings of an Olive ridley sea turtle (Lepidochelys olivacea) should be buried and protected under 40 cm of warm sand, but a domestic dog dug them out at Ostional beach in Costa Rica. Novembe...

Solvin Zankl / After an incubation period of 45 to 55 days and several days long ascent through the sand the hatchling Olive ridley turtles (Lepidochelys olivacea) emerge all together. Ostional Beach, Costa Rica, No...

Greg Basco/ BIA / Olive Ridley Sea Turtle (Lepidochelys olivacea) female coming ashore to lay eggs, Ostional Beach, Costa Rica

Greg Basco/ BIA / Olive Ridley Sea Turtle (Lepidochelys olivacea) female returning to sea after laying eggs, Ostional Beach, Costa Rica

Ingo Arndt / Black vulture (Coragyps atratus) feeding on Olive ridley sea turtle egg (Lepidochelys olivacea) on beach, Pacific Coast, Ostional, Costa Rica.

Ingo Arndt / Olive ridley sea turtle (Lepidochelys olivacea) swimming in open ocean not far from the nesting beach, Pacific Coast, Ostional, Costa Rica.

Ingo Arndt / Olive ridley sea turtle (Lepidochelys olivacea) female digging nest on beach for laying eggs, Pacific Coast, Ostional, Costa Rica.

Ingo Arndt / The villagers of Ostional clean the beach of driftwood after a heavy storm, that the Olive ridley sea turtles (Lepidochelys olivacea) can lay their eggs during the next arribada (mass nesting event) u...