Crow: Nictitating Membrane

The membrane is more clearly visible in large ("L").

I visited Mount Pond this morning: the sun was out and the sky was blue with some light fluffy clouds! Wonderful.

I photographed the gulls swooping for bread, but have chosen to blip this photo since it is the least (easily) replicatable photograph that I took; I happened (through luck not judgement) to catch this crow with its nictitating membrane ("third eyelid") across its eye, making it reflect blue rather than seeing the dark brown of its eye. The nictitating membrane of birds is transparent or translucent and allows them to blink (to moisten or protect their eyes) whilst maintaining some level of visibility.

This crow had been bending down over the edge to drink from the pond; the colours reflected in the water are from the rides at a fair taking place on the common.