WHITNEY'S ELF OWL 439 



The type specimen was secured by Dr. J. G. Cooper on April 26, 

 1861, near Fort Mojave, on the Arizona side of the Colorado River; 

 it has since been taken on the California side of the river. The type 

 remained unique for 11 years until Major Bendire (1892) found it 

 near Tucson, Ariz., of which he says: "On April 20, 1872, while 

 pushing my way through a dense mass of willows in the Rillitto Creek 

 bottom, I saw one of them perched in the thicket and shot it. Al- 

 though I had made considerable noise, it allowed me to approach 

 quite close and did not seem to be disturbed by my intrusion into its 

 retreat. I took several others subsequently, most of them shortly 

 after sundown, by carefully watching for the point from which they 

 uttered their call notes. When they find themselves observed they 

 sit quite erect and perfectly motionless, and may in such a position 

 be easily mistaken for a part of the limb on which they are perched." 



The chief haunts of the elf owl are the low, hot, dry Lower Sonoran 

 plains of the river bottoms and the adjacent tablelands in southern 

 Arizona. Here, at least, is its center of abundance, where it is the 

 commonest owl and one of the commonest birds. These plains are 

 scantily covered with a low growth of mesquite and creosote bushes, 

 mixed with various small cacti and chollas, among which the towering 

 candelabra of the giant cactus, or saguaro (Cereus giganteus), stand like 

 picturesque sentinels widely scattered over the hard, stony ground. 

 But these tiny owls are not wholly confined to these plains, for they 

 have been found elsewhere in that vicinity. Berry Campbell (1934) 

 writes: "In the minds of most ornithologists, there is no use in looking 

 for these owls outside of the sahuaro cactus belt. This error had 

 probably delayed their discovery elsewhere. Surely it is a mistake 

 to believe that they are limited, for, as mentioned above, they are 

 the most abundant of the owls in the Pefia Blanca area. That they 

 nest here there can be no doubt, for number 2164 is a juvenile still 

 in down. As I was stalking it, the parent came up and fed it." He 

 had already referred to the Pefia Blanca area as "characterized 

 chiefly as Upper Sonoran grassland. Only in the favorable localities 

 such as in ravines and the larger canyons and on the north facing 

 slope are brush and trees to be found. However, as the country is 

 quite broken, these situations are common enough to make a fair 

 stand of live oak, walnut, and sycamore possible." 



We found the elf owl breeding quite commonly in the broken, 

 higher, country around Sabino Canyon, where we collected six sets of 

 eggs on May 23, 1922. The nests were all in the saguaros, which 

 were growing all over the slopes, as well as in the valleys among mes- 

 quites, creosote bushes, various chollas, and palo verdes. At that 

 season the desert colors were at their best ; the saguaros were crowned 

 with white blossoms, the palo verdes were great bouquets of yellow 

 flowers, a blaze of brilliant color, the ocotillos were tipped with ver- 



