The calliope hummingbird is the smallest bird in all of the U.S., averaging around only 2.5 grams, or .005 pounds, according to Birds of the World. 

These tiny hummingbirds spend their winters in southern Mexico and their summers in the Pacific Northwest, making them the “smallest long-distance avian migrant in the world,” according to Birds of the World.

Each spring, calliope hummingbirds make their return to the Palouse region. Starting in mid-April, the hummingbirds arrive in their “usual” spots, such as the Pullman Community Garden at Koppel Farm. They make tiny, cup-shaped nests in the trees surrounding the gardens and, by the end of May, are feeding their young with nectar and bugs from the nearby flowers.