These two Little Gulls (Hydrocoleus minutus) were at Chew Valley Lake this afternoon. Usually, when Little Gulls turn up at Chew, they feed over the centre of the lake, way beyond camera range, but for some reason, these two birds chose to frequent Herriott’s Pool, the small body of water separated from the main lake by the A368.
These two are a non-breeding-plumaged adult (left) and a juvenile (right). Little Gull is the world’s smallest gull, much smaller than a Black-headed Gull (Chroicocephalus ridibundus). Adults have deep dark grey underwings, and the pale grey upperwings lack the finger of white along the front edge that Black-headed Gull shows. In breeding plumage they have black hoods and pink-washed underparts. Juveniles have a contrasting pattern of black, grey and white, lacking the gingery-brown tones of juvenile Black-headed Gulls. The black stretches from wing-tip to wing-tip across the back (the bird in the picture above has its wings fully outstretched; when the wings are in normal beating mode, the black forms a ‘W’ shape). Juveniles moult into first-winter plumage later in the autumn, replacing the black on the upperparts with pale grey, but the black on the wings remains, so the W is a good feature throughout the winter (note that juvenile and first-winter Kittiwakes have a similar pattern, but as long as you have a Black-headed Gull nearby for a size comparison you shouldn’t get the two confused).
Little Gulls do not regularly breed in Britain. Their main breeding colonies lie to the east of us, in marshes from eastern Europe and Scandinavia into Russia. They mainly occur in Britain on migration, in April and May, and then again from August to October. Flocks at Chew Valley Lake are usually of single-figures, or occasionally into double-figures. These numbers are typical for large wetland sites in Britain. There are two areas in Britain which regularly attract much large numbers, however: the Mersey coast, and the east Yorkshire coast. The former often attracts hundreds, and the latter has been known to host thousands. Small numbers of (usually first-summer) birds oversummer in Britain, mainly on the east coast, and occasionally make nesting attempts, although so far these have all been unsuccessful. Interestingly, breeding Little Gulls have successfully colonised the east coast of North America in the last hundred years, so the establishment of a British colony may be a possibility one day.
For more information on birds at Chew Valley Lake, Rich Andrews’ CVL Birding website is highly recommended.