EAC 8, Argo, January-March 1967
Page 8
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Transcription
7. Countercurrent. One bird was seen outside of this area at 12°18'S - 126°W. All those individuals seen closely were referable to this race. Tahiti Petrel (Pterodroma rostrata) Phoenix Petrel (Pterodroma alba) Separation of these two species in the field is still rather difficult. The best character at close range is the white line on the underwing of the Phoenix Petrel but this is very hard to see. To me the Tahiti Petrel is larger, and browner with longer, broader wings. I am positive that I saw Tahiti Petrels, but not so sure about the Phoenix Petrel. This group was found mainly in the region of the Countercurrent. Kermadec Petrel (Pterodroma neglecta) Eight Kermadec Petrels (3 intermediate phase, 2 dark phase, and 3 light phase) were seen north of the South Equatorial Current. This species was not restricted to the Countercurrent region as many of the other shearwater-petrels were. Herald Petrel (Pterodroma arminjoniana heraldica) Four Herald Petrels were seen south of 10°12'S, undoubtedly from the breeding colonies in the Pitcairn Islands or French Polynesia. At close range there is no trouble telling this species from the preceding one. A white line extends through the center of the Herald Petrel's underwing, which is not present in the Kermadec Petrel. The effect of this line is to give the Herald Petrel the appearance of a white underwing while the Kermadec only appears to have a white patch towards the end of the wing. This species also appears to be smaller than the Kermadec Petrel.