A Bi-Monthly Magazine o yt | 
N54: 
e t 2 \ & 
Western Ornithology onal Mv 
Volume XXIII November-December, 1921 Number 6 
[Issued November 19, 1921] 
HOME LIFE OF THE BLACK-TAILED GNATCATCHER 
By ROBERT S. WOODS 
WITH SEVEN PHOTOS ON FOUR BLOCKS 
States is the Black-tailed Gnateatcher (Polioptila californica), which is 
found in certain arid, brushy sections of the Pacific slope of southern 
and Lower California. The observations set down herewith were all made on 
the San Gabriel Wash at Azusa, in Los Angeles County. 
The habits of this species differ somewhat from those of the Western 
Gnateatcher, and the name ‘‘gnateatcher’’ does not appear to be so appropri- 
ate to it. Baird, Brewer and Ridgway (North American Birds, 1874) state 
that ‘‘at times it will dart about in the air in pursuit of small insects’’; but 
after watching these birds many times at all seasons of the year the writer 
has found this to be a decidedly rare occurrence, although they sometimes do 
hover momentarily to pick something off a branch; and an occasional snap of 
the bill at other times suggests flycatching activities even if one does not act- 
ually see the birds. In the locality mentioned, at least, the food is practically 
all obtained by search through the branches of shrubs. The birds do not seem 
to care for water, either for drinking or bathing. 
The Black-tailed Gnatcatchers do not wander much during the course of 
a year, and ordinarily it is possible to locate a pair at almost any time within 
an area of a few acres. They also confine themselves rather strictly to the 
brush, only casually visiting adjacent orchards or gardens. The eall-note varies 
considerably, but may be distinguished from that of the Western Gnatcatcher 
by a certain querulous tone and it is very thin and plaintive in character. 
The nest is deeply cup-shaped, sometimes slightly constricted at the top, 
and is compactly and neatly constructed of small pieces of grass, bark, fiber, 
paper, cloth, string, etc., and lined with small feathers, rabbit fur and soft 
cottony material. The interior measurements of three nests were 114 inches in 
diameter, by 114 inches in depth. 
The nest shown in figure 29a, into whose construction small bits of news- 
paper had entered largely, was found on June 25, 1920, just as the young were 
ready to leave. The four young birds were arranged in two layers, and of one 
of those in the lower layer only the beak was visible; yet on leaving the nest 
all seemed equally vigorous and well developed. One of the bottom ones, how- 
Cys of the most restricted in distribution of all the birds in the United 
