What triggers this mass nesting is still a mystery, but the importance of this spot has been recognized by all the major global environmental organizations. The peak season is from May to November during the new moon, however on any given night throughout the year you can still see turtles in fewer numbers.

The female will dig a hole large enough to encompass 70 - 150 "ping-pong ball" sized eggs. The whole process for each turtle -from the water and back- takes approximately an hour and a half. After about six weeks, little miniature turtle struggle out of the sand, and it's not uncommon to have their head pop up next to you while you're sitting on the beach. After surfacing, the race to the ocean is on. Scientists believe the species produce and over abundance of eggs to promote their survival. The more there are allows for a greater survival rate, however most of the eggs don't hatch, and most of the hatchlings never reach maturity.

Through a managed conservation plan, the residents of Ostional are allowed to harvest the eggs from the early stages of the nesting. Most turtles return to the beach several times and the earlier eggs tend to damaged by other turtles as the nesting progresses.

The giant leatherback turtles, as well as the rare and endangered green turtle also nests here, but in much smaller numbers. Ostional is decidedly a special place in the planet and deserving of the most dedicated conservation efforts.

If the surf is good at Guiones it can be better at Ostional. However, beware of the strong currents and hidden rock forms. Additionally, because of the turtle nesting, many underwater predators abound i.e. sharks. Add this to the strong rip currents and the hot black sand beaches and you're left with "user-unfriendly" swimming and surfing conditions.