I had a female mallard with a limp, she kept up okay but it lasted a couple of weeks. We figured she hurt it and kept an eye on her but these ducks are very wary of humans. Last weekend we found her dead in their coop. My husband said her leg looked fine, she wasn't bleeding, just dead and healthy looking. So I thought maybe she had had a bone infection or something? Now one of our fawn and white runners is limping. I don't know if it's worse or if her body shape makes it look worse, but shes having a lot of trouble keeping up with the others. She also looks perfectly healthy besides the limp. I worry she will show up dead as well or that she'll get caught by an opportunistic predator because she is weak. What could be causing this and how can we help her? I will catch her if need be, but I don't want to chase her down and catch her if I don't even have a plan beyond that... Thanks in advance!