You've heard of a red herring or a white elephant, but what about a purple heron?

Yes, honestly, a purple heron, a rare visitor to Britain, was spotted at the Carymoor Environmental Centre near Castle Cary over the Easter weekend.

This striking bird is closely related to the more familiar grey heron. But it has a dark grey back and reddish brown neck, appearing much darker in flight, a characteristic which drew attention to its presence on Good Friday afternoon.

Volunteers building a floating island for breeding water birds in the neighbouring Carymarsh wetland saw the bird fly up from one of the reed beds and it was identified by experienced birder Bruce Taylor. He was able to capture the bird's visit on his camera.

The heron roosted at Carymoor overnight and was seen again the next morning, but flew off in a southerly direction on Saturday evening.

Purple herons usually breed in southern Europe, but small numbers are seen in Britain each year, and one bred successfully on the Dungeness peninsular in Kent for the first time last year.

It is thought that as our climate gets warmer this species may set up home in Britain and start breeding in the same way that Little Egrets, once a rare species in Britain, did over a decade ago.