352 BIRDS OF NEW MEXICO 
(Barrell), where the first had been seen the previous spring on the early date of 
February 25. 
It probably does not winter regularly in-the State though it was found at Hachita 
as late as December 15, 1889 (Anthony). 
In spring, it arrived March 22, 1913, at 6,600 feet on the East Gila River (Ligon). 
The northern part of the State is not usually reached until early April. _ W. W. 
Cooke. 
Nest. In crevices of rock in cliffs, caves, quarries, or ruinsj made principally of 
feathers instead of twigs, glued together with other soft materials and also glued to 
the rocks. Eggs: 4 to 6, white. 
Food.— Winged ants and other hymenoptera, bugs, flies, dung beetles, engraver 
beetles, clover root weevils, leaf hoppers, etc. 
General Habits. Besides the El Moro National Monument 
many of the loftiest cliffs and deepest canyons of New Mexico are 
associated with the white-patched forms of the White-throated Swifts, 
which, clean cut as arrowheads, dart through the sky at incredible 
speed, their peculiar, sharp, vibrant note filling the air. At Juan 
Tafoya they were seen around sandstone cliffs near an old cliff dwelling; 
later, around the vertical walls of the Enchanted Mesa and at Acoma 
numbers of them were flying across the face of the cliffs, appearing 
and disappearing in the long seams of the rock that doubtless furnish 
thein with homes for their young. 
At Lake Burford early in June, 1918, when Doctor Wetmore found 
them apparently stopping during their northward migration, they were 
seen circling high in the air and feeding over the flats. Near his cabin 
they joined a band of \ iolet-green Swallows that were coursing back and 
forth above the sagebrush, feeding on the swarms of chironomids 
driven in by the wind (1920a, p. 400). 
In the fall migration we were stirred by the sight of a flock of 
the aeronauts, their rocky fastnesses left behind, high above a lake, 
winging their way across the sky to their distant southern homes. 
In the Carlsbad cave region, Mr. Bailey often saw them passing 
over the entrance to the main cave, hurtling by “with lightning-like 
speed,” perhaps on their way to Slaughter Canyon about fifteen miles 
to the west, where there was a smaller cave which a colony of Swifts 
had long shared with big-horned mountain sheep. The age of the 
colony was demonstrated by the amount of Swift guano accumulated, 
three car loads having been taken out, packed down the trail on burros, 
and shipped to California as fertilizer. A great crack in the roof some 
seventy-five feet above the floor seemed to offer safe nesting sites, but 
owls and ring-tailed cats, both common in the cave, had preyed upon 
them extensively, judging by the number of their bones found in owl 
pellets on the floor and “wing feathers with quills clearly cut by the 
teeth of some carnivore” (1928a, p. 149). 
