The archipelago is home to a diverse breeding seabird community, with more than 175,000 pairs of birds visiting each year.
Ten of the islands that make up the archipelago have been designated as Important Bird Areas by Birdlife International. Eighteen different types of breeding seabirds can be found nesting among these huge colonies, and restoring and conserving these habitats is a key aim of the Chagos Conservation Trust.
Among the most notable species that call these islands home are the sooty terns (Sterna fuscata), the brown and lesser noddies (Anous stolidus and A. tenuirostris), the wedge-tailed shearwaters (Puffinus pacificus) and the red-footed boobies (Sula sula).
The red-footed booby is the smallest of its family, with a fully-developed wingspan of around four and a half feet. It can be found nesting on the atolls in the summer months, and spends its winters out at sea. It can be recognised by its bright red feet, and while it lays only one egg a year, it lives for more than 20 years.
Threats to these species include loss of habitats, and the depletion of prey caused by over-fishing. Introduced rat colonies on the island also affect many ground-nesting species.
The protection of these islands, the removal of rats and the re-establishment of native forest are allowing seabird numbers to increase.