20 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 123 



few individuals. Although large numbers do not appear until late 

 May, pale-footed shearwaters are known to arrive in the Arabian Sea 

 as early as mid-April (see Bailey, 1966) and, hence, records near the 

 Maldives would not be unexpected at this time. 



The status of the other dark shearwater in the Arabian Sea, the 

 wedge-tailed shearwater, is particularly hazy because of the ease of 

 confusion with Bulweria fallax. For years it was considered to be 

 the common dark petrel in the western Arabian Sea (Alexander, 1931 ; 

 Phillips, 1954) until these records were reexamined (Jouanin, 1957) 

 in light of the discovery of B. fallax, which is very similar in appear- 

 ance. Although a few specimens have been taken in the Arabian 

 Sea, wedge-tailed shearwaters certainly appear to be rare there, for 

 Bailey (1966) recorded none positively north of 10° N and I saw but 

 one. It seems necessary, therefore, to establish just how common 

 this species actually is in order to determine whether only occasional 

 stragglers are involved or whether there are enough to justify postu- 

 lations of either a local population or a migratory movement from 

 another part of the Indian Ocean. The latter possibilities have been 

 suggested (Bourne, 1960), and the idea of a local undiscovered breed- 

 ing population seems especially attractive in view of several recent 

 discoveries of small breeding populations of this species on tiny rock 

 offshore islets, for example near Madagascar (Appert, 1965), Reunion 

 (Jouanin, pers. comm.) and Roderigues (Vinson, 1965). In this 

 connection also, the Maldive Islands may harbor a population of 

 wedge-tailed shearwaters, thereby accounting for some of the shear- 

 waters seen at sea in that area. 



Just now being established is the regular occurrence in the equa- 

 torial regions of the Indian Ocean of two storm petrels from the Pacific, 

 Oceanodroma monorhis and 0. matsudairae. Although their num- 

 bers seem to be greatest during the northern summer (Bailey, in 

 prep.), my observations indicate that at least small numbers are 

 present throughout the year. One cannot help but wonder if there 

 are also undiscovered breeding populations of storm petrels in the 

 Indian Ocean, and again the Maldive or perhaps the Chagos Islands 

 seem likely locations. In addition to Oceanodroma species, Bulweria 

 bulweria, which has been recorded in the Indian Ocean (Phillips, 

 1959; Bourne, 1960; Jouanin, 1957), might also be sought. 



Perhaps the least understood seasonal change in the western Indian 

 Ocean are the movements of the sooty terns that breed in the 

 Seychelles and Amirante Islands in huge numbers from May to 

 October and that then disappear for the remainder of the year. 

 Whether they move to other island groups, such as the Aldabras, 

 Chagos, or perhaps Cargados Carajos Shoals, or spend these six 

 months at sea is unknown. In February I saw no sooty terns north 



