Sept., 1922 163 
CACTUS WRENS’ NESTS IN SOUTHERN ARIZONA 
By FLORENCE MERRIAM BATLEY 
T the north base of the Santa Rita Mountains between 4000 feet at Mc- 
A Cleary ’s, now Nicholson’s (where we camped during the winter of 1920- 
21), and Continental at 2900 feet on the Tucson-Mexico spur of the South- 
ern Pacific, throughout both the mesquite and catsclaw slopes leading down 
from the mountains and the cholla cactus flats of the lower terraces, nests of 
the Cactus Wrens (Heleodytes brunneicapilus cowest) were the most conspic- 
uous ornithological features of the landscape. 
Near 4000 feet a well-populated patch of mesquite, catsclaw, and zizy- 
phus, which was conveniently located on the Continental road and bordered 
above by the fence of the cattle ranch and below by the telephone line from 
Madera (White House) Canyon, included approximately fifty-three acres and 
was utilized for an intensive study of Cactus Wren nests. 
Thirty-seven nests of sufficiently recent use to show in which direction 
they faced were found here. . Seven of these were certainly disused, and three 
apparently so, the remaining twenty-seven, in January or February, showing 
fresh entrance material or other signs of readiness for occupation. 
WINTER ROOSTS 
About the middle of December, when a flurry of snow whitened the Santa 
Rita peaks and a number of cold nights made warm nests especially desirable, 
I surprised two Cactus Wrens busily carrying warm lining materials to a nest 
in a ball of mistletoe. Remembering Mr. Anthony’s notes in Zoe (11, 2, pp. 
133-134) on the remodelling of New Mexico Cactus Wrens’ nests for winter 
roosts, I looked forward to seeing more of the interesting process. But his 
dates, which I had forgotten, showed that the work of rebuilding was going on 
during pleasant weather from October 24, and about the first of December 
‘‘all of the nests of the vicinity were so thoroughly repaired that they had 
every appearance of new nests.’’ In the Nidiologist he recorded finding the 
wrens ‘hidden in their nests during a snowstorm in November.’’ 
Unfortunately | did not begin taking the census of the fifty-three acres 
until January 12, and no other Cactus Wrens were seen carrying material until 
spring. By January 18, when I had listed and tagged thirty-one of the thirty- 
seven nests, the structural part of the remodelling was all too evidently fin- 
ished, although a few straws and many feathers were added to some of the 
nests still later. From January 13 to February 15, twenty-three of the twenty- 
seven good nests on the fifty-three acres were found occupied at sunset, which 
by repeated experiment was proved to be the retiring hour. Among the mis- 
cellaneous nests outside the fifty-three acres (also examined at sunset) on 
February 2 and 11 seven more were found occupied, making a total of thirty 
nests found used as winter roosts. Much to our surprise, on our twilight 
rounds a Bewick Wren was twice flushed from one of the Cactus Wren nests. 
A cholla cactus nest of the Cactus Wren in the giant cactus belt below, had - 
also been used as a roost by a bird of another species, the mouth of the nest 
being carpeted with the ordure of a large bird. 
