get an e collar, or you can take him to a pro trainer and he'll probably use one, there a very vaulable tool, any good dog or any dog at all, can use one without ruining the dog, it's the user that will ruin the dog, just as long as you condition him to it first, he'll be fine, you can use a check cord also, whenever one of my dogs doesn't come straight back, or doesn't come back fast enough, I use just a light nic and they know what it means, but if I were to light em up and make there eyes glow, they'd probably never pick up another duck, I'd look into one and get a book. there a invaulable training tool.