THE MEXICAN SCREECH OWL. 369 



On March 26, 1872, I found one of their nests in an old Woodpecker's hole 

 in a willow stump not more than 7 inches in diameter and about 6 feet from the 

 ground. The cavity was slightly over 2 feet deep, and the four eggs it con- 

 tained, which had been incubated for a few days, were lying on bits of rotten 

 wood and a few dead leaves, not sufficient to call a nest. The female was at 

 home and had to be taken out forcibly, protesting and uttering a hissing sound, 

 and, after being turned loose, snapping her mandibles rapidly together from her 

 perch on a small walnut tree, into which she had flown. I was in hopes she 

 might continue to use the same site again, but was disappointed in this. 



Mr. Herbert Brown, of Tucson, finds this race nesting frequently, in that 

 vicinity at least, in the sahuara cactus (Cereus giganteus), which are often used 

 as nesting sites by both the Grila Woodpecker (Melanerpes uropygialis), and 

 especially by the Gilded Flicker (Colaptes clirysoides), being easily excavated 

 and affording both roomy and secure homes in which to rear their families. 



1 believe such cavities are selected in preference to any others by the Mexican 

 Screech Owl, as well as the more numerous Elf Owls. In a recent letter 

 received from him, he writes me: "I have found the Mexican Screech Owl 

 nesting in holes of sahuaras within 4 feet from the ground, and from that 

 distance up to almost the extreme top of the plant. The sahuaras along the 

 river bottoms, and on the mesas bordering them, are their favorite nesting 

 grounds. At the head of the pass leading through the Tucson Mountains, about 



2 miles from the Santa Cruz River, there is a large forest of immense sahuaras, 

 some of them 60 feet high and both body and limbs bored full of Woodpeck- 

 ers' holes. As nearly all were too large to climb, I cut several down, but failed 

 to obtain a single Owl of either this subspecies or the more common Elf Owl, 

 and at the Quijota, 90 miles southwest of Tucson, I also cut down a num- 

 ber of these in a similar location some distance from water, with the same 

 result, and I have come to the conclusion that these Owls only occupy the 

 sahuaras growing in the lowlands and not those in the higher hills or out 

 in the deserts. 



"They are pugnacious and wicked little fellows, who will use their claws, 

 and bite as well, on the least provocation. Small birds, kangaroo rats, gophers, 

 different species of mice, lizards, scorpions, grasshoppers, and beetles are their 

 staple articles of diet. From the lateness of the season in which I have occa- 

 sionally found them nesting, I believe that two broods are sometimes raised 

 in a year; still I have no actual proof of this." 



In the oak regions of southern Arizona they nest in the natural cavities 

 of these trees, most of which are hollow. Mr. 0. C. Poling found two of their 

 nests in such trees, one on May 1, the other on May 5, 1890. 



Nidification begins occasionally in the last half of March, continuing 

 through April and the first week in May, according to altitude; birds breeding 

 in the hot valleys nesting fully a mouth earlier than those living in the moun- 

 tain regions. 



26957 Bull. 1 24 



