What a difference a month makes! Well, actually, not quite a month – my first photo below was taken on 21 December, the other two today, 15 January.

Two juvenile drake Greater scaup (Aythya marila) have been over-wintering in my local area, some days on the lakes at Cosmeston, some days in Cardiff Bay, either at the wetlands reserve or on the opposite side of the bay, near Ferry Court, always in the company of the flocks of Tufted ducks.

When they were first sighted, it was difficult to tell them apart from the female Tufties, so brown were they in appearance. But, as you can see in these photos, they are gradually acquiring more grey feathers on their backs and white on their lower bodies.

In February and March, scaup begin to migrate to the Arctic in preparation for breeding, though, according to my bird guide, some immature birds remain in their wintering grounds over the summer months. It will be interesting to see what these two decide to do.