The importance of Sky Islands in the annual cycle of the Western (Cordilleran) Flycatcher Empidonax occidentalis
For more than a century and a half the Madrean sky islands, a group of 55 mountain ranges that occur from the middle of Arizona to the southern end of Sonora Mexico and rise from the desert floor to 3,000-10,000 feet elevation, have been a Mecca for ornithologists and natural historians. The ornithological literature of the late 19th early 20th centuries is filled with the wonderfully detailed and colorful accounts of expeditions and discoveries by Charles Bendire, Elliott Coues, William Brewster, William Earl Dodge Scott, Harry S. Swarth, and Herbert Brandt, to name but a few. The Huachuca, Santa Rita, and Chiricahua Sky Islands in particular, received a great deal of attention, being renowned for producing rare Mexican strays --- Recent sightings of The Red Warbler and Brown Flycatcher at Rose Canyon on Mt Lemmon attest to the continued northward movement of species that are usually only seen in Mexico. Throughout the 20th century, ornithologists such as Russell P. Balda, Steven M. Russell, James T. Marshall Jr., and J. David Ligon produced a wealth of natural history information, while long-term studies, such as that of Jerry and Esther Brown on Mexican Jays in the Chiricahuas, made substantial and lasting contributions to our knowledge and understanding of birds.