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Case Summary for:
Submission No 249: Franklin's Gull Larus pipixcan; Southbank, Brisbane, QLD, 18 June 1998. Submitted by: Stuart Pell and Robert East. Verdict: Accepted This case concerns the well-publicized sighting of a hooded gull on the banks of the Brisbane River between the 18 June 1998 to at least the 24-June 1998. The bird was first located at Hamilton on the Brisbane river prior its stay at Southbank, close to the Brisbane city centre. During its stay the individual was seen by many local and interstate observers. A rare bird report form was presented to the committee along with a series of excellent photographs and field notes that serve to validate the claim. The black hood, mid to dark-grey upperparts, small size, prominent eye-crescents, slender bill and the diagnostic upperwing pattern all serve to conclusively identify this bird as a Franklin's Gull safely eliminating the closely related Laughing Gull Larus atricilla and other hooded gulls. Ageing the bird is more difficult. The following characters as documented in the field notes or in the photographs are, in combination, diagnostic of a Franklin's Gull in second alternate or definitive alternate plumage; (1) smaller size relative to Silver Gull, (2) nearly full black hood marked with broken but rather thick prominent white eye crescents, (3) limited amount of mottling around the base of the bill and throat, (4) fine slender black bill with a scarlet tip, (5) dark red legs and feet, (6) mid to dark-grey upperparts with strongly contrasting and prominent white scapular and tertial crescents, (7) dark-grey upperwing with broad white trailing edge and, most importantly, the diagnostic primary pattern of black on wing tips clearly separated from grey on bases of same outer primaries by a narrow white bar, a ready distinction from all ages of Laughing Gull, (8) a short white tail appearing square-cut or gently rounded at the tip with a light grey wash on the central part of the tail (just visible in one of the photographs). The committee agreed unanimously with the observers that this bird was indeed a Franklin's Gull Larus pipixcan. And most likely (based on primary pattern) a bird moulting into its second alternate (second summer) plumage. This sighting representing the 9th confirmed record for Australia.
References and Bibliography
Tony Palliser |