Scuba Diver Australasia + Ocean Planet
COCOS ISLAND
Between hammerhead schools and hundreds of reef sharks – the remote national park island off Costa Rica is a guarantee for spectacular shark dives. Together with the well-known Galápagos Islands and the Malpelo dwarf archipelago, Cocos represents the third point of the “Hai” triangle in the Eastern Pacific. Nowhere else will you have a better chance of encountering large hammerhead schools and vast numbers of whitetip reef, Galápagos, silky, and even tiger sharks.
Marine biologist Dr. Randall Arauz discovered that some tiger sharks spend up to nine months in Cocos Island before they disappear again in the vast ocean. These hikers have been known to travel for thousands of kilometres, but are capable of staying in one place for months if they like it. As pronounced omnivores, they will eat any prey that comes their way, and as a result, Cocos Island has seen fewer eagle rays and turtles, either from being preyed on or as a safety measure.
On the other hand, hammerhead sharks have been tracked patrolling around the three islands – Galápagos, Malpelo and Cocos. Remarkably, they can cover the 800 kilometres between Cocos and Galápagos within two days! However, these animals have also been found swimming outside the protected areas to feed and mate, particularly along the mainland coast between Guatemala and northern Peru where some marked animals have been caught. The shallow water is host to dense mangrove populations that provide refuge for young hammerhead sharks in their first year. Large numbers of hammerhead sharks have also been caught in the Eastern Pacific, which has led to the question: Is the national park actually effective in protecting these voyaging sharks?
MUST-SEE
BAJO ALCYONE – Famous for its incredible seamount that starts at 25 metres and extends down to 40 metres, Bajo Alcyone is a conglomeration of hammerhead sharks, manta rays and mobula rays. Due to the strong currents, only advanced divers are allowed to attempt the site.
DIRTY ROCK – More accessible to new divers, Dirty Rock is a similar dive featuring pinnacles and boulders that create a protected channel. The rock, covered in barberfish, breaks the surface and drops down to 35 metres. But the main attraction is the incredible number of hammerhead sharks that greet you as soon as you enter the water.
WHEN
1978
WHERE
Costa Rica
WHAT National Park and UNESCO
World Heritage Site