Tuesday, April 20, 2010

Gulls and Doves

While the migration has been keeping us busy, local birds have been getting on with the business of breeding. Two species have benefited from their association with humans and our habitats and they would not have featured prominently, or at all, in the bird lists of the 19th Century naturalists who explored these parts. The Yellow-legged Gull is hardly mentioned yet today a massive colony breeds on the Rock of Gibraltar, their numbers having built up since the 1970s.

These birds are now sitting on eggs, three being the usual clutch size. We will monitor their progress through the spring.

These birds are now highly aggresive and do not tolerate an approach to the nest. They will get even more aggressive once the young hatch.

The other bird certainly did not feature at all in the 19th Century accounts. The Collared Dove (above) established itself in south-east Europe around 1900. They gradually spread west across Europe and the first pair bred in Britain, in Norfolk, in 1955. They spread south into Iberia somewhat later and spread rapidly in the 1990s. The European population has been estimated at 7 million breeding pairs! It should not be confused with its close relative the Turtle Dove (below) which is a summer visitor, wintering in sub-Saharan Africa that occupies open countryside and rarely ventures into towns.

Collared Doves are ahead of the gulls! The first fledged youngsters are now flying about the gardens in the town, like these by the Gibraltar Museum this morning

adult for comparison

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