>>55598Making traps selective can be tough. Traps in general are indiscriminate if not used carefully. If you are targeting a specific species, it's your job to learn all you can about its habits to pinpoint your catch.
For coons and possums, a dog proof trap, or DP can be used (pic related). Only animals with dexterous paws can reach in the tube and pull the trigger.
If you don't have access to these, using sweet as opposed to meat baits will make you almost coon specific. Use fish, old meat, or beef and you will catch the occasional dog or cat. Use molasses, sweet cereal, syrup, or marshmallows and you will get coons.
As far as fox and coyote traps not being visited by dogs, I can only suggest not canine trapping in proximity of dogs. Coyotes, fox, and dogs are pretty close on the family tree biologically despite how behaviorally different they are today. They respond to the same kinds of things, so any coyote set is highly likely to entice Fido as well.
As far as being selective goes, traps help, bait helps, but nothing takes the place of a little common sense in picking a location.
Biggest rule of thumb, a 16 dollar raccoon is not worth mangling up someone's 2000 hound. If you have any, ANY doubt whether or not it is safe to set there, don't.