Waterfowl training dog collars are always waterproof and submersible, going a step further than the field trainers. These dog collars are for dogs who will be primarily working with hunters pursuing waterfowl, and hopefully your dogs are good swimmers! These training systems are expandable, covering multiple dogs, as well as having a consistent range of up to a mile or so. Tri-Tronics and SportDOG make a very good waterfowl dog training collar. The SportDOG Wetland Hunter, for example, is camouflage-colored and can accommodate up to six dogs in one system and has a 1 mile range, an ideal range when it comes to hunting waterfowl.