The Desertas Islands are a small group of uninhabited islets located off Madeira. Deserta Grande (10 km2) is the largest, followed by Ilhéu Chão (0.4 km2) and Bugio (3 km2). From afar, these long and narrow islands rise up like sharp ridges, whose impressive cliffs tower to over 400 m, reaching their maximum height on Deserta Grande at 479 m. The main geomorphological features are low-lying platforms at the foot of the cliffs. Most were formed by historical landslides, such as at Doca, the anchorage point on Deserta Grande, and the site of the only permanently inhabited buildings, a house for the keepers and the nature reserve visitors centre.
The declaration of the nature reserve in 1995 (although the Desertas had been legally protected since 1990) meant that fishing and other human activities were regulated. Today fishing is banned in a broad area that mainly corresponds to the current habitat of the Mediterranean monk seal (Monachus monachus), as this critically endangered species of pinniped needs calm conditions in which to breed and feed.
These islets were already known in the 14th century, but were not officially discovered until 1420, coinciding with the arrival of the discoverers in the rest of the archipelago of Madeira. Ownership passed through several hands, including those of an Englishman, a Mr Henry Carvely Hinton, until the Portuguese government took control in 1971. Although the Desertas were never inhabited on a permanent basis, several attempts at colonization were made and animals were introduced in the 15th century. Small numbers of a breed of goat, supposedly a descendant of the pre-Hispanic Canary Islands species, still survive today. Moreover, cereals were planted, and orchilla (lichens of the genus Roccella) and barilla or saltwort (annual plants of the genus Mesembryanthemum) were collected. Military surveillance posts, built in the Second World War, were used for sighting and subsequently hunting whales, and specimens of Cory’s shearwater (Calonectris diomedea borealis) were also caught. These activities disappeared completely when the Desertas were declared a protected area and after environmental awareness campaigns and strict surveillance. Today these islets are mainly used for scientific research, conservation of natural resources, and guided tours for education and tourism.