Hey, so this is a two year old thread, and I only stumbled into it because I'm looking for whether or not a 4-H dad would really want to buy ducklings from me, but I've got an argument for pinioning or dewing.
So, first, let's define what pinioning is so I don't back up something I can't condone:
I only pinion my muscovies. Pinioning is removal of the wing after the last joint during the first seven to ten days of life. During this time the duckling's body is funneling everything into body growth. The wing tip is only cartilage and skin at this point. It's less traumatic than getting your ears pierced and the duckling seems more upset at being picked up and restrained than the brief fraction of a second it takes to remove the end of his wing (about 1/4 inch of it). There's usually only a few drops of blood, and the duckling is back to normal usually in 12 hours or less. With Muscovies, they can still fly, but only four or five feet into the air when they really get scared or excited. Usually it's just about two feet in the air once they become adults. If you want no flight, you'd have to take all their wings off and that would be TERRIBLY BLOODY AND PAINFUL. The cartilage will already be calcified there so the body will be funneling blood and resources there to support it. The thought just makes me wince so I'm going to move on.
Now my argument: I have a totally fenced in acre. My birds free range all day unless I see hawks or foxes around or I'm integrating chicks or something, then I keep them penned, but most of the time they're free in the swamp to run around and be ducks and chickens with each other. They get to have a blast all day, and let me tell you, they all fly, but only about as much as you'd expect a chicken to fly. I have three muscovy ducks that aren't pinioned and I haven't been late on the female, but last year I wanted to try leaving my favorite drake, a big, heavy, multiple year, friendly guy unclipped and about a week after his molt finished he flew super high, from one end of the yard to the other in one try so I rounded him up and duck rodeoed him and he was mad at me for like a week after. Basically he could have been over my house and then anywhere in no time at all if I hadn't intervened. The problem is, I live by a major interstate and several main roads with a bunch of aggressive and bad drivers. They'd either hit my duck as soon as look at him on the main roads, and/or he'd cause a collision with his 12-15 lbs body on the interstate that at 70+ (more if speeding taken into account, that's the local limit) could kill someone. I'm also not allowed to keep birds if they leave my property where I live. If I wanted to keep my muscovies in unpinioned I'd have to be hyper vigilant about clipping as soon as the blood receded in those flight feathers, but that's hard enough with only three unaltered animals, or keep them in a covered, and therefore more than likely smaller than an acre pen, which would be no fun and they wouldn't be able to do their mosquito control duty that I got them to do. And I love my birds. Keeping them penned all the time would break my heart and theirs and make me not want to keep them at all. Several people I know have lost ducks and guineas and chickens to cars in the country but if they'd pinioned the flying ones as chicks and fenced them in, the bird would still be alive and they'd never have to worry about watching for molts or catching them and it only takes a second! I also don't think it would actually increase egg yield because it shouldn't be the whole wing, just the last part but it is good for staying friends with your flying ducks and keeping them safely in your yard.
Now a pinion job done wrong, that would be terrible, so not everyone should do it and I'm not saying people should pinion everything on a whim, but when it comes to species that are hard to catch and maintain clipped it might be best to withhold judgment or even consider it. Living, well fed, safe, and free ranging ducks are happy ducks, limited flight ability or no.
But hey, to each his own. Just keep all birds off the (75 mph rural speed limit) roads, especially in Michigan where the DOT is trying to kill everyone without the birds' help, lol. They've got potholes and deer for that.