I saw this mallard for the first time at the local lake tonight. I've never seen a head so plucked apart before. Any idea what's going on here? Is he just an unwelcome guest or is something else going on?
Axel, I wondered that but also wondered if it wasn't an aggression thing since mating/nesting just finished up? I've only seen mites this bad one other time and that was on a bald headed cardinal.
Could be ectoparasites like mites, or harassment from other ducks for one reason or another. Under-feathers over head are still there but these could be replacement feathers. Male ducks moult their bright plumage in mid-summer and transition to an "eclipse" plumage for a while. They look like females at this time. I don't think this is what we are looking at here.