If you plan on eating the chickens and ducks, I'd give a lot of thought to purifying their water. I don't know how much "industry" is in New Mexico but traces of heavy metals, chemicals and other toxins can be found in rain water in industrialized areas (or down wind from those areas). I've seen plans for a home built purifier (layers of gravel, sand and charcoal) for rain water somewhere but don't recall where.