Well lucky for you, your coyotes are among the dumbest in the world, around here there is not way you would ever catch one in a havahart or any other box trap, the only possibility would be a pup just old enough to wander away from the den without the mother being that dumb to get into that trap. There is plenty of human scent here as well but there are also plenty of people hunting and trapping them so the get educated. The only way to catch them around here is leghold traps and you have to have well planned sets and make darn sure you don't leave any scent, rubber boots, hip boots or chest waders work best, some even lay down tarps in the areas they have to kneel and work in to set the traps, and even these traps are often busted. The only other good way beside leg traps is neck holds, which is basically a snare which has a stop on it so it doesn't allow for strangulation, but these have to have the right situation to work well and legally.