 By comparison, the 13-inch-long Arctic tern makes a one-way flight of about 11,185 miles, or 51,430,000 body lengths, just 65% of the body displacement during migration by rufous hummingbirds.The northward migration of rufous hummingbirds occurs along the Pacific flyway and may be time-coordinated with flower and tree leaf emergence in spring in early March, and also with availability of insects as food.Arrival at breeding grounds before nectar availability from mature flowers may jeopardize breeding opportunities.