Well that's a interesting idea using a dog to tail them back to the den do you look for a track or something showing were a fox has passed or just let them in a good area let them found a track and see if they lead to a den also I have been thinking would you think a bait station would be a good place to cut a track and work it back also would you think they would have a good chance of flushing a coyote like you do a fox