The Grey Heron as a Predator of Mallard Chicks

This morning, Zoe and I saw this grey heron making several attempts to catch the mallard chick shown in this photograph.  The male mallard would chase the heron off whenever it came near, but the female and the chick seemed to have no sense of danger and repeatedly swam past the heron as if they didn't notice it.  I can now quite understand how initial broods of 11 or more chicks can be whittled down to one or two within just a few days.  The Egyptian geese are much better parents: they still have all 9 of their goslings.

Photo taken in by the large lake, Reading University grounds, Reading, UK, on 2009-04-19.