chickens. Grandpa wasn't very happy about it so he tied one of the dead chickens around the dog's neck and left it there the rest of the day.
The dog couldn't get it off and couldn't get away from that dead chicken. It was a miserable puppy that day, the chicken was half her size. She learned her lesson very well and from them on was afraid of chickens. Wouldn't go near them.
So you could try tying a dead duck around his neck for a day. Probably shouldn't let your neighbor see though because I doubt it is humane.