Male and Females do differ

Another day, another walk, to the Deer Park (don't actually think this is its name but there are deers!) With a friend and her young son so we lingered over the ducks (literally as on the bridge) and spent a long time looking at the differences between the male and females and if we could tell the young ones from the older ones. Is it their beak colour?! Nice respite from end of year company accounts and the VAT quarter which was my day.