Mallard - 5

I tried to get a picture of a shoveller today but it spent all the time swimming round in circles with its head under water so no luck there. I will try again next time I am at Christleton pond as I have seen it there several times.

The picture nicely shows the mallard's third eyelid, a feature which is apparently quite common on birds, reptiles and animals. The nictitating membrane moves horizontally across the eye rather than up and down. It is translucent and not only protects the eye but moistens and cleans it.