Grijze Alk bij de Bruine Bank

We report a sighting of a grey Razorbill, near the Brown Ridge in the Southern North Sea, on 26 January 2010. The bird flew by in a group of five, all of them, including the aberrantly coloured bird were in winter plumage. Plumage parts that are normally black in Razorbills were pale grey in this individual. This colour aberration, in which pigment concentrations are strongly reduced, is called ‘diluted’. Colour aberrations in Razorbills might be rare: we only found one earlier case, of an all-white bird shot in the Firth of Forth in 1836.