The Desventuradas Islands, a remote archipelago in the Pacific Ocean, offer a glimpse into isolated ecosystems. Their uninhabited nature and distance from continental influences make them a unique area for scientific interest. This isolation has shaped distinct biological communities, leading to ongoing exploration and conservation efforts.
Geographical Characteristics
The Desventuradas Islands are located approximately 850 kilometers (530 miles) off the coast of Chile, northwest of Santiago. This small group consists of four main islands and islets: San Félix, San Ambrosio, Gonzáles, and Roca Catedral.
These islands are of volcanic origin, featuring rugged terrain with dramatic cliffs. Their combined land area is around 5.36 square kilometers (2.07 square miles). San Ambrosio is the highest, reaching 479 meters (1,572 feet). The semi-arid climate is influenced by the cool, nutrient-rich Humboldt Current, which moderates temperatures but results in limited rainfall.
Historical Context
The discovery of the Desventuradas Islands is often attributed to Ferdinand Magellan. However, the first confirmed sighting was by the Spanish navigator Juan Fernández on November 6, 1574, during a voyage from Callao to Valparaíso.
The name “Desventuradas,” meaning “Unfortunate Islands,” was given due to their uninhabited and barren nature. Historical records indicate the islands were later named after Saint Felix and Saint Ambor, with “Ambor” eventually becoming “San Ambrosio.” There is no evidence of prehistoric human activity on these islands.
Ecological Significance
The isolation of the Desventuradas Islands has fostered significant ecological diversity, making them a biodiversity hotspot. This isolation has led to distinct evolutionary pathways, resulting in a high degree of endemism for both terrestrial and marine species. For instance, the flora includes 22 species, with 19 being endemic. Notable endemic plants include the shrub Thamnoseris lacerata, which can form small trees, and Suaeda nesophila.
The islands serve as important nesting grounds for seabirds like petrels and boobies, whose guano contributes to the terrestrial ecosystem. The surrounding marine environment is distinct, influenced by the Humboldt Current, supporting a unique mix of tropical, subtropical, and temperate species. Marine expeditions have revealed high levels of endemism among fish species, with over 70% of observed fish species found only in this ecoregion. The waters also host the Juan Fernández fur seal, which is endemic to this archipelago and the nearby Juan Fernández Islands.
Conservation and Accessibility
The Desventuradas Islands are largely uninhabited, with only a small detachment of the Chilean Navy stationed on Isla San Félix, which also features an airport. In 2015, the Chilean government established the Nazca-Desventuradas Marine Park, encompassing approximately 300,000 square kilometers (115,844 square miles) of ocean surrounding San Ambrosio and San Félix. This designation made it one of the largest marine protected areas in the Americas.
The marine park implements a no-take policy, prohibiting fishing and other extractive activities within its boundaries, although some areas allow for continued sustainable lobster fishing by the Juan Fernández community. The Chilean Navy assists in enforcing these regulations. Access to the islands is highly restricted, primarily limited to scientific research and conservation efforts. This limited accessibility helps protect their unique and sensitive ecosystems from human disturbance, preserving their distinct biodiversity.