Okay I am only guessing but you have dogs so you probably know they can have sepration anxiety and other emotional problems, I am wondering if Pete isn't having something like this? you said you took Pete to live at your boy friend parents house because they have chickens? I'm sure that was trmatic for Pete, he was separated from you and his dog friend, and now he has 2 new ducks that he has to get use to, plus he really isn't sure what he is a duck or a dog. so I'd say Pete is having suffering from PTSD, don't laugh it is probably true. I had a dachshund that when he got stressed out would lick his foot till he had it raw and bleeding. animals suffer stress. Think back to when all this started and see if you can draw any conclusions from this. I'm not blaming you for this but just think about all Pete has had to deal with lately. Ducks like Routine and calm quiet atmosphere, maybe his life has been a little to hectic lately. Just guessing though. I'd still get him some Nutri Drench and add it to his water, if he is having stress issues he needs so vitamins to help him through