We just discovered that runner duck has one eye closed and is a bit off. The feathers around that eye look to be a bit matted, so there's probably discharge, although I can't see what the discharge actually is. I gave her a big bowl of water to dunk her head in, but from her standoffish behavior, I don't think it's just an eye problem, but a sign of possible sickness. She's hiding herself behind some bushes, so that's an extra clue that I think she is sick. Does anyone have advice?