My best dog was “Riggs” a Chesapeake bay retriever. Big and strong and not supposed to be a great upland dog but he and I got all but one species of upland bird available in my state and several species elsewhere and that’s before you start on the waterfowl list. He lacked only ptarmigan which we found later but he did pick up band tailed pigeon lost in black pine forest. Don’t discount the heavy retrievers!