Easter Island (Rapa Nui) and Sala y Gómez Island are Chile's only subtropical marine environments supporting reef-building corals. The depauperate coral communities of Easter Island, one of the world's most isolated marine outposts, form topographically complex and aesthetically appealing subtidal seascapes. Little is known of the coral fauna and coral communities of Sala y Gómez Island. Information on Easter Island's coral fauna has increased slowly, from sporadic taxonomic studies in the early to late 1900s to a comprehensive reconnaissance of subtidal communities published in 1988. Ecological/geological studies from 1998 to 2000 (and continuing) are now adding rapidly to our knowledge of Easter Island coral community structure and reef growth potential. Eleven species of zooxanthellate corals are currently recognized and only two of these, Pocillopora verrucosa and Porites lobata, contribute significantly to live substrate cover. Easter Island's position near the western arm of the South Pacific subtropical gyre explains its moderately warm marine climate, with seasonal mean monthly sea surface temperatures ranging from about 19° to 25°C. Low nutrient concentrations in the euphotic zone dictate low phytoplankton production and generally clear waters with high visibility (−20–40 meters). Coral communities are prevalent around most island exposures, best developed from about 5 to 50 m depth, except for the southeastern shore which is frequently subject to strong wave assault. Live coral cover is often near 40% and reaches 80 to 90% in some areas. Incipient reef frameworks of P. lobata, 2–5 m in vertical relief, are present at some sites along the northeast coast. While some relatively minor coral mortality has been noted, due to the muricid gastropod Coralliophila and unidentified sources, coral bleaching and mortality resulting from anomalous high sea temperatures in the year 2000 represent the most serious recognized disturbance. Man's current utilization of coral communities at Easter Island is for harvesting organisms for local food consumption or harvesting corals and invertebrates to be sold to tourists. Unfortunately, little information is available for any resource species. Official statistics or estimates of population size, fishing effort or pressure have not been kept at the same pace as on mainland Chile because many of the harvested species are locally consumed and have not been declared fished resources. Corals themselves are either sold as whole bleached colonies or as carved statues, jewelry and parts of other curios. Pocillopora spp. are the primary targets of the curio trade, with Pocillopora verrucosa constituting 90% of coral items for sale in local markets. No permits are required to extract corals and there are no enforced limits on the numbers or sizes of corals or fishes taken. Despite the lack of basic information and formulation of a management plan, the Chilean government has realized the importance of protecting these coral communities that contain a high percentage of endemic species. With the recent (2000) establishment of Chile's first three submarine parks at Easter Island, this new level of governmental sanction, with increased public awareness and support, should help sustain the biodiversity and vitality of the island's unique coral communities.

Mesophotic “mentions”
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Classification
* Focused on 'mesophotic' depth range
* Focused on 'mesophotic coral ecosystem'

Fields
Community structure
Disturbances
Oceanography

Focusgroups
Scleractinia (Hard Corals)

Locations
Chile - Easter Island