It is a strange sensation to be woken by the shrieking of seagulls –
more so because I am a good hour’s drive from the coast. The sound of the gulls
takes me back to childhood holidays in Cornwall and Devon, where the birds were
part of the holiday experience and something that sat alongside fish and chips
and ice cream in a cone. That the gulls have now become part of my inland
soundscape has everything to do with a change in their behaviour.
We have seen a huge increase in the numbers of inland-breeding gulls and
a good number of our cities now support breeding colonies of lesser
black-backed and herring gulls. While numbers are increasing over much of the
UK, there have been declines in the gull colonies of northern Britain and
Ireland. The birds here in Thetford are lesser black-backed gulls and this is a
species for which we have seen a significant increase in the use of man-made
structures, particularly rooftops, for nesting. I suspect that some of the
large, flat-roofed, industrial units on the edge of town are being used by
these birds.
The numbers of gulls present inland during winter has also increased and
mixed flocks, often in the company of black-headed gulls, can be seen on fields
and around the many piggeries that have become a feature of the Breckland
landscape. On occasion, there are even lesser black-backs in with the
black-headed gulls on the river at Thetford.
It is thought that these increases, both in winter and during the
breeding season, are linked to a change in the feeding opportunities available
to the gulls, coupled with a reduction in the levels of persecution. Increasing
quantities of food waste seem to litter our streets and our landfill sites now
contain vast quantities of organic waste and kitchen discards, all of which provide
access to food throughout the year for these opportunistic birds. During the
winter months other gulls may join the local birds from further afield, with
some arriving from elsewhere in Europe to winter here. At the same time, some
of our birds leave Britain to winter elsewhere: a few lesser black-backed gulls
winter as far south as West Africa, underlining just how mobile these birds can
be.
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