Pap I use a jack russel for tracks which are'nt much more than 2 to 3 hours old.He's found three for me already.Two of them still alive stopping them,with him buzzing around the deer like a bumble bee.No prior training whatsoever.Gotta put him on it with a dog lead though,It's pot luck when you turn him loose.He's a part of my family that's for sure.He earns his keep like the rest.