There is nowhere else on earth like the atoll of Aldabra. It is the finest surviving tropical atoll ecosystem on earth.
The Aldabra Group consists of the islands of Assumption, Cosmoledo, Astove and Aldabra itself.
Located 1,150 km south west of Victoria, 408 km north west of Madagascar and 640 km north east of the Tanzania-Mozambique border (the nearest point of land on the African continent, Aldabra Atoll is the worlds largest raised coral atoll, separated into 4 islands by narrow channels of water. Picard and Polymnie are the 2 smallest, followed by Malabar, then Grande Terre or ’South Island‘ the largest, infact Grande Terre is the second largest island of Seychelles (larger than the combined areas of the next three largest, Praslin, La Digue and Silhouette. The island of Mahe, which is the largest granitic island, can fit comfortably in the Aldabra lagoon.
Declared a UNESCO world heritage site in 1982, Aldabra is home to many species of plants and animals. There is little soil, practically no fresh water, no guano, no phosphate and no deep-water anchorage. The jagged coral can quickly tear shoes and feet to ribbons.
The Aldabra Rail is the largest flightless bird in Seychelles, because it had no natural enemies it had no need of its flying abilities. Other species of seabirds include 10,000 pairs of frigate birds breeding in one of the worlds largest colonies.
Aldabra is also home to the worlds largest giant tortoise population with 100,000 animals. Each year, several thousand green turtles come to the island to breed as do a smaller number of hawksbill turtle.
Dugong dugong was thought to be extinct from Seychelles, due to mass hunting in the early days of settlement, but they have been sighted in the Aldabra lagoon, especially in the recent years.
Cosmoledo Atoll lies 1,045 km west of Mahe island. It is a raised coral atoll. It stands on the same volcanic foundation as Astove. Some 19 islands form the Cosmoledo Atoll, namely Pagode, Grande Ile (or Wizard) and Menai. The atoll was inhabited as a fishing and Turtling station until 1992 when it was abandoned. Menai and wizard are both named after british vessels that visited in July 1822. Cosmoledo is an important Bird Area. There is a globally important population of masked booby, red-footed booby and sooty tern (reaching 1 million pairs, this is the largest colony in Seychelles). There are tall mangroves on Cosmoledo, as on Aldabra but coconut palms are common only on Menai where they were planted.
Astove Atoll lies 1,045 km southwest of Mahe and stands on the same volcanic foundation as Cosmoledo. Treasures have been found on Astove consisting of silver coins, forks and spoons. Today the island is uninhabited. Astove is renowned for its butterflies including large numbers of species such as eyed pansy. Giant tortoises were reintroduced on Astove from Aldabra. The Astove Day gecko is also an endemic species to Astove.
Assumption Atoll lies 1,140 km south west of Mahe. It is the largest outer island after Aldabra. Discovered by Captain Nicholas Morphey on 14th August 1756, the island was given its name after the religious feast of the Assumption the following day. The Abotts Booby, one of the rarest seabirds in the world, was found on Assumption, but it is today extinct as much of the vegetation the seabirds depended on was destroyed. The only indigenous animal on the island is the insectivorous Mauritian Tomb Bat.
Assumption is one of the most devastated islands of Seychelles, guano was scraped off the island by the thousand of tonnes, trees were eradicated and in consequence many of the endemic flora and fauna died out. However with an already existing Airstrip, tourism may flourish on Assumption in the future, notably the island has one of the most pristine beaches in Seychelles and the coral reef life is dazzling. Much of Jacques Cousteau‘s famous underwater film The Silent World was shot around Assumption and Aldabra.