A really easy way to catch them is with empty milk containers or laundry soap containers something along those lines. Then tie a piece of metal leader to it with a heavy duty hook. Let some chicken livers sit out in the sun for a while then bait the hook and toss them out in the middle of the pond. Pull them up the next day and more then not you will have snappers on there. My father use to catch ones the size of manhole covers like this all the time.