Le parc national de l'île Cocos, situé à 550 km au large de la côte pacifique du Costa Rica, est la seule île du Pacifique tropical oriental possédant une forêt tropicale humide. Son emplacement – au premier point de contact avec le contre-courant nord-équatorial – et la myriade d'interactions entre l'île et l'écosystème marin environnant font de ce parc un laboratoire idéal pour l'étude des processus biologiques. Le monde sous-marin du parc national est devenu célèbre et de nombreux plongeurs le considèrent comme le meilleur endroit au monde pour observer les grandes espèces pélagiques comme les requins, les raies, les thons et les dauphins.
Parc national de l'île Cocos
Le Comité a inscrit le Parc national de l'Ile Cocos au titre des critères naturels (ix) et (x) car il fournit un habitat d'importance critique pour la faune marine, y compris de grandes espèces pélagiques, en particulier les requins.
[Uniquement en anglais]
Cocos Island National Park, located 550 km off the Pacific coast of Costa Rica, includes the entire Isla del Coco and the marine ecosystems up to a distance of 15 km around the island. Is the only island in the tropical Eastern Pacific with a tropical rainforest. Its position as the first point of contact with the northern equatorial counter-current, and the myriad interactions between the island and the surrounding marine ecosystem, make the area an ideal laboratory for the study of biological processes. The underwater world of the national park has become famous due to the attraction it holds for divers, who rate it as one of the best places in the world to view large pelagic species such as sharks, rays, tuna and dolphins.
The island is of volcanic origin consisting of basaltic rock which presents a rugged relief characterized by an irregular coastline with cliffs rising almost vertically from a narrow shore to heights of 200m. There are two bays (Bahía Wafer and Bahía Chatham) with sandy beaches. Inland, the terrain is mountainous with numerous rivers and streams, many of which plunge over the peripheral cliffs in spectacular waterfalls.
The underwater profile of the island consists of stepwise shelves with almost no intertidal zone and a shallow submerged fringing reef, culminating in sand and Porites rubble at the edge of a several hundred metres deep trench. The most important reefs are located in Punta María, Punta Presidio, Punta Pacheco and some areas of the Iglesias, Chatham and Wafer Bays. The southern and south-western sectors show the greatest bathymetric variation in the area, with emergent small islands (such as Dos Amigos, Rafael and Juan Bautista), and a great number of submerged rocks.
As other oceanic islands, Isla del Coco presents an impoverished flora with respect to that of the continent, but with a high number of endemic species (at least 70 species of vascular plant). The vegetation is exuberant and owes its lushness to the heavy rainfalls and rugged relief, which favours condensation.
There is a rather low diversity of terrestrial fauna. Some 87 bird species have been recorded in the nominated site including three endemics: Cocos Island cuckoo; Cocos Island flycatcher and Cocos Island finch. Red-footed booby and brown booby, great frigate bird, white tern, and common noddy form breeding colonies on the surrounding small islands and rocks. Two species of endemic reptiles have also been identified, anolis lizard and gecko. Except for introduced pigs, goats and cats, there are no terrestrial mammals on the island.
Marine mammals include bottlenose dolphin and California sea lion. Hawksbill, green and olive ridley turtles inhabit the surrounding waters and use the beaches occasionally. The fish fauna is exceptionally rich and is moderately diverse, 300 fish species having been recorded. Vast migrations of hammerhead shark, and white-tip shark and fish pass close to the island. Whale shark and manta ray are also abundant.
There is no evidence indicating that Isla del Coco was occupied during pre-Columbian times. The island has been known to mariners and cartographers since the first half of the 16th century. However, its position was vaguely indicated and therefore, could only be located by experienced sailors. Fishermen, pirates, commercial sailors and scientific expeditions arrived at the island searching for fresh water and shelter. Source : UNESCO/CLT/WHC