About the Revillagigedo Archipelago
The Revillagigedo Archipelago consists of four volcanic islands that are located 250 miles due south of Cabo San Lucas in Baja California Sur and 370 miles west-southwest of Cape Corrientes in Jalisco. They are administered by Mexico and in 1994 were classified as a Nature Protected Area under the denomination of Biosphere Reserve by UNESCO (United Nations Educational, Scientific and Cultural Organization).
In 2002 the Mexican government outlawed commercial fishing in the area. The four islands are Socorro, San Benedicto, Roca Partida and Clarion. Socorro is the largest island. San Benedicto is 40 miles north of Socorro and Clarion is 250 miles west. Roca Partida, the smallest island, is 60 miles west of Socorro.
The first evidence of human habitation on the Revillagigedos Islands is from Spanish explorers in 1533 when they discovered Socorro and named it Santo Tome and four days later discovered San Benedicto and named it Inocentes. Clarion and Roca Partida
were discovered in 1779. There are no facilities on the islands as they have no reliable sources of potable water, however, the Mexican Navy established a naval base on Socorro in 1957 and there is a small outpost on Clarion.
The islands are on the northern end of a submarine ridge where, approximately 3.5 million years ago, there was an expansion of the ocean floor. Their continuing volcanic activity also makes the Reserve a geologically important site. The latest eruption was
on San Benedicto in 1952.
The marine fauna of the Biosphere is known for its high diversity of invertebrates, particularly crustaceans, mollusks, echinoderms and corals and for its high level of endemism. There are 22 species of hermatypic (reef building) corals, of which more
than half are found only near oceanic islands of the Eastern Pacific, and near to one third is found only at the Archipelago of Revillagigedo. There are also 156 species of mollusks on the islands, 99 species of echinoderms, 92 species of crustaceans, three of
which are endemic. The fish fauna of the archipelago also presents a high degree of species richness with at least 321 species, including 20 species of shark and five species of ray. The waters surrounding the Revillagigedo Archipelago represent an
important feeding, breeding and transit area for cetaceans of the Mexican Pacific, in particular the Humpback whale. Sixteen species of whales and dolphins have been registered in the area. There are also four species of sea turtle that feed, nest and develop in the area.
Thirty years ago the Revillagigedo Islands were one of the richest archipelagos in the Eastern Pacific. They have been called the Mexican Galapagos and are as fragile and diverse but less well known as their namesake. World famous for the abundance of apex predators like hammerhead sharks, giant pacific mantas, and yellowfin tuna, these islands have been decimated by over-exploitation. What remains is greatly threatened. According to 2003 survey reports and fisherman interviews wahoo populations have decreased 70-80% since the 1970s. Sharks have decreased 50-60% and fish such as Blue Jack, Rainbow Runners and Leather Bass have decreased 30-40%. The primary threat to the underwater populations is commercial fishing. A single longliner can greatly impact marine populations for many years. Unfortunately, due to their distance from the mainland and the separation of the islands enforcing the fishing ban that the Mexican government imposed in March 2002 is problematic at best. This is the gap that the Socorro Conservation Fund wishes to fill by providing aerial surveillance in the biosphere. You can help. Not only are you protecting many important species and a unique ecosystem, your generous donation is tax deductible.