By Charlotte Owen
You might look at a black-headed gull at this time of year and wonder how on earth it got its name, since there is just a hint of a dark smudge behind each eye. The black head, which is really more of a dark face mask, is worn exclusively for the summer breeding season when it is used in courtship and territorial displays. Although it looks black from a distance, the true colour is a deep, chocolatey brown. Outside the breeding season the ‘black’ heads are bare, and you’ll need to look out for alternative identifying features including their dark red legs and bill, and black tips to the primary feathers.
While the common name is a bit unhelpful, the scientific name means ‘coloured-headed and laughing abundantly’ – which is far more accurate. These highly sociable birds gather together in noisy, squawking flocks, constantly uttering a rasping ‘kree-arr’ cackle as if enjoying a joke with a punchline that only they understand. But it’s not just their laughter that’s abundant, and this is the UK’s most numerous gull species. Numbers peak in winter, when the resident population is bolstered by an influx of birds escaping the cold of continental Europe and further afield. In some years the Sussex population has exceeded 80,000 (of around 2 million across the whole of Britain) and individual flocks can be impressively large too, particularly in stormy weather. Groups of up to 10,000 birds have been seen roosting together on inland lakes and reservoirs at night, before heading out the next day to feed. They are bold and opportunistic foragers, happily gobbling whatever they can get hold of, and you’ll see them trailing behind tractors or following fishing boats to take advantage of an easy meal. In the water, they feed while swimming by seizing prey from the surface or dipping their head underwater, while on the coast they will probe for shrimps and marine worms - or catch thrown chips on the wing with ease. There is always plenty of squabbling and they will readily steal food from each other and from other birds, always laughing as they go.
black-headed gull, summer plumage © Dave Kilbey