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Case Summary for:
Submission No 262: Bulwer's Petrel Bulweria bulwerii; off Southport, Qld, 27th February 1999. Verdict: Not Accepted This case that relates to the sighting of a bird on a pelagic off Southport, Qld (28.05'S - 153.52'E) on the 27th February 1999. A number of observers were present, two of whom provided the notes which form the basis of this submission. The sighting was brief, but good views were obtained by those who managed to see the bird first. Although the descriptions lack precise detail, there is much to indicate that a small, all-dark Bulweria petrel was seen: an overall sooty-brown colour, dark bill, long-pointed tail, small size relative to accompanying Wedge-tailed Shearwaters Puffinus pacificus, and an erratic, twisting flight low to the water, all of which tend to support Bulwer's Petrel Bulweria bulwerii and aid in the elimination of the little known Jouanin's Petrel B. fallax. The latter should appear larger relative to the Wedge-tailed Shearwater and supposedly has a stronger and more arcing flight pattern, which recalls the larger gadfly petrels and, as pointed out in the submission, would be well out of range off the east coast of Australia. The long pointed tail suffices to rule out an all-dark Oceanodroma storm-petrel. The real difficulty remains in ruling out Macgillivray's Petrel Pseudobulweria macgillivrayi. Although known from only two definite records, it is believed that Macgillivray's Petrel does still exist in Fijian waters and may be more common than presently known. Consequently, the species should be regarded as a potential vagrant. It is close in size to Bulwer's Petrel and reportedly lacks the contrasting pale diagonal bar across the secondary upperwing coverts shown by Bulwer's Petrel (Harrison 1987). The fact that the observers failed to detect this pale bar, despite brief but close views (at one point down to only 10m), tends to suggest Macgillivray's rather than Bulwer's Petrel. Fig. 90c, plate 27 (Harrison 1983) depicts the all-dark appearance of a Bulwer's Petrel when seen at a distance, but there is no suggestion that the species ever lacks the pale bar altogether. Despite having many points in favour, with the apparent lack of a pale upperwing bar being the most important adverse feature, it was considered by Committee members that the description is not sufficiently detailed to resolve the identification. However, it was agreed that the record should be treated as highly likely and it will be documented as such.
References and Bibliography
Tony Palliser |