New Mexico Ornithological Society - New Mexico Bird Finding Guide: Fourth EditionNew Mexico has the 4th highest bird diversity of any state in the U. S. with nearly 550 species documented within its borders including over 300 species known to breed. At a biological crossroad between east and west and north and south, the state's birdlife is influenced by the Rocky Mountains, Great Plains, Great Basin and Chihuahuan deserts, and the sierras of northwest Mexico. An elevational range from lowland desert and rivers below 3,000 feet to