Monday, 27 April 2009

A spring passage of LIttle Gulls

It is easy to see why the lake at Livermere is such a magnet for visiting waterfowl and waders. Situated in an open expanse of agricultural land it is an obvious feature for any bird passing over the borderlands of west Suffolk. The lake can be particularly productive during April and May and has already turned up trumps this spring, with a sizeable passage of Little Gulls noted on April 6th.

Varying numbers of Little Gulls had been reported from other inland waterbodies that morning, including the nearby lakes at Lackford, and I was certain that I would see some at Livermere. What did surprise me, however, was the number of individuals present, with several dozen birds passing through en route to breeding grounds in Finland, northern Russia and the Baltic States.

Almost immediately upon arriving at the lake I raised my binoculars and picked out the delicate dancing forms of the Little Gulls, swooping and darting about in a tern-like fashion to pick food from the water’s surface. By comparison, the more familiar Black-headed Gulls that were also present seemed almost cumbersome in their movements, less agile on the wing and with a greater tendency to bicker among themselves. Some of the older Little Gulls showed a dark underwing, a character that becomes more prominent with age and which can usefully be used when picking the birds out from among other gulls. In with the second-year and adult plumaged birds were a number of first-years, sporting a black tail band and bold black ‘W’ pattern extending across the wings and back. This is another useful feature that can be used in the field. Mind you, the general feel of these birds is very different from other gull species and they are pretty easy to spot once you know what you are looking for. Little Gulls are dainty birds. With a wingspan some 20-30% shorter than seen in Black-headed Gull, they are the smallest of the World’s gulls. This goes some way to explaining their tern-like jizz and the light, almost dancing, flight. Unlike terns, however, they show quite rounded wings, a feature that is further accentuated by the pale tips to the longest of their flight feathers.

An inland movement of this size is unusual but not unprecedented and, since 1994, there has been a tendency for increased numbers to pass through our region on spring passage. Individuals also appear on the coast at this time of the year, and Titchwell is a favoured site a little later into Spring, regularly attracting a couple of dozen birds. In 2007, Little Gulls made a nesting attempt at Titchwell, only the fifth British record. Who knows what might happen this year?

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