The tropical shearwater is found in the tropical parts of the western Indian Ocean from East Africa to southern India and in similar regions of the Pacific from just to the southeast of JapantoFrench Polynesia.[3][4]
The total population has not been definitively quantified. Aride IslandinSeychelles has the world's largest population on a single island with an estimated 26,118 pairs.[5] Smaller numbers of the subspecies P. b. bailloni breed on the nearby islands of Cousin, Cousine, Recif, and a few other small rat-free islands.[6] Subspecies P. b. dichrous is estimated to number 1,000–10,000 pairs on the Line Islands and 10,000–100,000 pairs on the Phoenix Islands, with the nominate subspecies thought to number 3,000–5,000 pairs on Réunion and fewer than 100 individuals on Europa (reviewed by Brooke 2004), though it is thought there are many more breeding colonies on other islands in the Pacific. The population seems to be stable.[1]
^ Aride Island Special Reserve Annual Report April 2021 – March 2022. Island Conservation Society, Island Conservation Society, Seychelles, 2022, p. 11
^Skerrett, A.; Disley, T. (2011). Birds of Seychelles. Christopher Helm. ISBN978-1408151518.
