All fish may eat the leaches, I have no idea, do a google search on them for fish bait, you might be surprised at what you find out. This is just like using salamanders, beter known as spring lizards or water dogs, they are the best smallmouth bait around, some people use them if they can find them. When I was a kid I used wasp larve out of wasp nests that I tore down, that is the best brem bait to be found anywhere and they are free if you can find a nest. Don't rule out any bait.