They both pretty much eat the same thing, so your going to have to wade through the coyotes until you find a fox. I've called coyotes on fox distress and just about every call I can think of from the smallest mouse squeak to deer distress. Reds don't seem to be very prevolent in coyote country. I used to trap a lot of fox, when coyotes started showing up in the traps the red fox catch would drop off.