Most of the waterfowling in WY is in the agricultural country like on the east side of the state near Nebraska. Not exactly right in the mountains. Look into Bump Sullivan and Table Mountain on WGFD site for example. Decent hunting can be had all over the state on potholes, ponds, lakes and rivers- get a public land map or look at the online map on WGFD site. I do well enough hunting public access in the Laramie and Platte River valleys.