Monday, 13 October 2008

Riding out the storm

The onshore gales that are a feature of October bring with them birds more often encountered on the open ocean. If you are brave enough, and well prepared with several layers of windproof clothing, then you can spend a profitable morning seawatching, scanning the horizon for passing birds with your telescope. Many remain distant and difficult to identify as they are repeatedly picked-up and then lost from view, rising and falling in flight to dip below the crests of growing waves. In amongst the more commonly encountered species may be scarce birds like Great and Sooty Shearwaters; it is for these birds that many seawatchers brave the elements, hunkered down out of the worst of the wind.

However, for me it is the more common Gannets that tend to catch my eye. These striking birds, with their dazzling white adult plumage and black-tipped wings, have always fascinated me. I have been fortunate enough to see them on one of their breeding islands and to marvel at their two metre wingspans close-up. The breeding colonies themselves are boisterous affairs, as neighbouring pairs squabble, and the associated noise gives rise to the feeling that you are in the middle of a troublesome football crowd. Grounded, Gannets are somewhat ungainly but when on the wing they exude the grace and power of a heavyweight plunge diver.

Many of the Gannets passing east along the North Norfolk coast in autumn are young birds, fledged from one of our northern breeding colonies and now following the impulse to migrate south. Gannet chicks invariably leave the nest carrying extra fat reserves and so, having made the first short flight down from their island colonies, they land on the sea and find themselves too heavy to take off again. As such, their journey south begins with the bird swimming. Once some of the fat reserves have been used up, the youngster is able to take to the wing and begin its journey proper, passing down either the Atlantic or North Sea coasts and into the Bay of Biscay. These young birds show the strongest migratory urge and many migrate as far south as Senegal or beyond. Although Gannets typically do not breed until their fifth or sixth year, many do return at least some distance north the following spring. In fact, as the birds get older more of them return to the breeding colony, such that by the fourth year many males will set up a small nest site and attempt to recruit a mate. The Gannets that are passing our shores now are a mixture of ages (and plumages) and well-worth seeing. While you may see one on a still day, it is the rough ones that boost the numbers passing close inshore.

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