When we began our research, nobody expected us to find very many sea turtles inside Golfo Dulce — most sea turtle activity was thought to occur on the Pacific side of the Osa Peninsula. It turned out that chelonids were the most frequently seen family of animals, accounting for 38 percent of our total sightings. Discovering such significant numbers of sea turtles was one of our most important findings. Sadly, fishermen with many years of experience in Golfo Dulce say the sea turtles there have declined at least 30 percent in recent years.
Jorge and I documented three species: Pacific Black sea turtles, still commonly referred to as “Greens” (Chelonia mydas agassizii), Olive Ridley sea turtles (Lepidochelys olivacea) and Hawksbill sea turtles (Eretmochelys imbricata). Locals also reported seeing near-extinct Pacific Leatherback sea turtles (Dermochelys coriacea) inside Golfo Dulce. That’s four endangered species of sea turtles utilizing the embayment. Amazing!
Our biseasonal data show Golfo Dulce to be a year-round feeding and breeding area for endangered Green sea turtles. We logged over a hundred sightings of them between both surveys. This species, by far the most common, was usually observed in the upper regions of the gulf resting at the sea surface. But we also documented Green sea turtles mating in all four quadrants of the inlet, so their use of the fiord waters appears widespread.