Friday, 23 July 2010


In the UK I am used to seeing the graellsi form of Lesser Black-backed Gull (LBBG). This is the palest race of LBBG which breeds in the UK, Ireland and the Faeroes. Then there is the slightly darker intermedius form which breeds in western Europe (this is the main race breeding in Denmark). Further east there is the darkest of them all - fuscus - which breeds in eastern Sweden, Finland and possibly on the northern coast along the Norwegain/Russian border.

Yesterday at Damhussøen, in between watching the Caspian and Yellow-legged Gulls, I noticed the few intermedius LBBGs on site. I took three photos, only seconds apart so in the same light and with the same camera settings, illustrating the subtle variation in this species. The first is at the paler end of 'intermedius', similar to a 'graellsi' LBBG, the second a classic 'intermedius' and the third is at the darker end of 'intermedius', close to the tone of 'fuscus'. Note also the difference in the size of the white 'mirrors' on the primary tips. (I recommend clicking on the photos to big them up..).

The darker bird was wearing a Swedish metal ring. I managed to read the number and have reported it, so hopefully I'll soon know the history and origin of this bird.

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