Hi everyone. I'm new and live in England in the UK. I came across this site looking for answers about mallards. So I've joined. What I want to know is when does a mallard duckling finally develop his green markings. We have a wild duck who walked into our garden (would you call this a backyard?) and led her 20 ducklings into our small, natural pond. I feed everything that enters our property because we like wildlife so started feeding her and her brood. They stayed for about 90 days, by which time mum had gone and they were practising flying and landing on the pond. Then one day they all took off together, flew over the house and were gone. Their wings sounded like a small motor. A week later Mum waddled back with another 15 and they are still here. The first brood all looked like females to me, even at 90 days. So I want to know if they develop later than that.