Bird migration as they ride the "roaring forties" outside the breeding season. The tubenoses spread widely over large areas of open ocean, but congregate when food becomes available. Many are also among the longest-distance migrants; sooty shearwaters "Puffinus griseus" nesting on the Falkland Islands migrate between the breeding colony and the North Atlantic Ocean off Norway. Some Manx shearwaters "Puffinus puffinus" do this same journey in reverse. As they are long-lived birds, they may cover enormous distances during their lives; one record-breaking Manx shearwater is calculated to have flown 8 million km (5 million miles) during its over-50 year lifespan. Some large
Chagos Archipelago fuscata"), brown and lesser noddies ("Anous stolidus" and "Anous tenuirostris") wedge-tailed shearwaters ("Puffinus pacificus") and red-footed boobies ("Sula sula"). Land bird fauna is poor and consists of introduced species and recent natural colonisers. Red fody had been introduced and now widespread. Environments of Chagos Archipelago provides rich biodiversity and support varieties of cetacean species within the vicinity, such as three populations of blue whales and toothed whales (sperm, pilot, orca, pseudo-orca, risso's and other dolphins such as spinners, and so on). Dugongs, being locally extinct today, once thrived in the archipelago and the Sea Cow Island was named after the