Well David I have a small pond about 1/5 of a acre and have natives and coppernose with catfish as well. I stocked the natives first out of a freinds pond using a minnow trap. Did about 50, also ordered some coppers to stock 50 as well. To help answer, just my opinion, There is no big differences at all. I stocked 2 years ago and both native and coppernose are about the same size. some of the coppernoses are maybe a 1/3 of an ounce bigger and thats not much. Average weight is 9-12 oz. I also have stocked some native out the same pond i got these at that were already 10 oz. They are over 1 pound 1 1/2 years later. I think it's all about controlling the population correctly for ANY type of species you deal with. Thats just my opinion though.