Friday, December 15, 2006

Off to roost

click photo to enlarge
Winter is a great time for watching birds. The trees are bare, and birds are much more visible in woodlands and gardens. Winter migrants have taken the place of summer visitors, and a number of resident birds have their populations swollen by an influx of continental birds fleeing the colder weather. Moreover, even the least interested in our feathered friends cannot fail to notice that in winter many bird species go around in very big flocks.

Each evening large, dipping and swirling clouds of starlings fly over my house. These flocks, many thousands strong, are made up of smaller groups that have spent the day foraging over fields and woods, gardens and villages. They are heading for a large roost on a seaside pier where up to thirty thousand congregate nightly. These small birds keep low on their evening flight, but higher up are gulls, also heading for their favoured nightime roost. Some prefer a freshwater lake, others congregate in particular fields, whilst many prefer a coastal sandbank or island. Surveys have shown that about two and a half million gulls cluster in roosts across Britain each night.

If I walk down to the seashore in winter great swarms of knot, looking like swirls of smoke, can be seen flying offshore as the tides drive them from one feeding place to another. And on the edge of the water, looking, at a distance, like dark stranded weed, stand multitudes of oystercatchers and turnstones. To see these birds take to the air, twisting and turning together as one, perhaps startled by a peregrine as it dives into the panicked flock, is a wonderful sight. So, why do birds gather in this way? Well, experts tell us that it's partly to more effectively find food, partly to pass on species characteristics to younger birds, but also for protection from predators - many eyes have a better chance of seeing the enemy early, before it is upon them! Whatever the reasons, these winter displays make a marvellous spectacle for those who care to look.

My photograph shows gulls heading for a roost as the sun sets over the roofs of Fleetwood, Lancashire. The full image didn't have enough detail across the frame to tie the composition together, so I've cropped a vertical section from it. I took the shot without a tripod, but with the camera firmly pressed against an upright post. I used a long zoom lens at 300mm (35mm equivalent), with the camera set to Aperture Priority (f6.3 at 1/160 sec), ISO 100 with 0EV.
photograph & text (c) T. Boughen