Migration Info The details of the spring migration of this species are poorly known. One source of confusion is the fact that the females of this species are virtually identical to those of the closely related Allen's Hummingbird, which precede them up the U.S. west coast. The first Rufous males reach the southern part of their breeding range in central Oregon as early as late February, while other individuals are still moving through the vicinity of Jalisco, Mexico. The bulk of the Allen's population moves through central California in mid-April. The return migration in fall is primarily to the east, through the Sierra Nevada, the Great Basin, and the highest portions of the Rockies, timed to coincide with the bloom of high-elevation nectar sources.