20211008 Baltic Gull ID plate
Baltic Gulls pending, comments from BBRC and NRC.
Top left to centre image: 8th Oct 2021 Cley Marshes pre-roost. Foreground adult Baltic Gull Larus fuscus fuscus, in retained breeding plumage as 3rd summer and older. Showing smaller domed head and thinner bill than congeners. Thin but obvious mirror on P10 and primary tips worn. Brownish tint to black upperparts. Full breeding plumage retained on this well built individual. Centre bird adult winter Lesser Black-back, L fuscus intermedius. Extensive head and neck striking in October and blueish dark grey upperparts, appraoching blackish... Single wide mirror on P10 and well tipped primaries. Rear bird adult winter Yellow-legged Gull, L michahellis. Minimal Head streaking in this species winter plumage and mid bluish grey upperparts. Large squarer head and heavey bill.
Bottom left image: 5th June 2018 Titchwell Freshmarsh. 2nd summer Baltic Gull. Near adult plumage with browner tones in wing coverts. Long primary projection beyond tail gives an extremley attenuated rear end of Baltic Gull. Mirrors could not be detected in this birds primaries. Domed head and thinner high contrast bill on which a hint of a dark sub-terminal band could be seen.
Bottom right image: 20th August 2016 Cley Marshes. Remains of black band on bill agan. Its worth waiting for a full body stretch with any suspect Gull such as this to reveal remnants of a black band in tail and to check moult progression in remiges. Single small mirror on P10 without any white tips as in adult plumage, although P1-P3 look new with unwarn wide tips.
The potential for pure L f fuscus vagrants is still on the cards following some concern over there status. See Dominics Mitchells article 'identity crisis' Birdguides and British Birds 111: 499-511.
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