These remarkable images show an extremely rare form of blue-tit, which has black and brown plummage instead of the more commonly seen pale blue feathers.

The bird has been drawing a stream of visitors to its home in Whisby Nature Reserve, in Lincolnshire, where the more widely known pale blue-tit appears in abundance.

One visitor who was keen to see what all the fuss was about and who made who made a special trip to seek out the unique bird, was 47 year old photographer Lee Smith.