SAN LUCAS CACTUS WREN 233 



HELEODYTES BRUNNEICAPILLUS AFFINIS (Xantiis) 



SAN LUCAS CACTUS WREN 



HABITS 



Although this wren was originally described from the Cape region 

 of Baja California, its range is now extended northward over more 

 than half of the peninsula, to about latitude 29° ; it apparently inter- 

 grades with hryanti somewhere south of San Fernando. 



Kidgway (1904) gives the best description of it as follows: "Most 

 like n. h. 'bryanti but much paler, with under parts less heavily and 

 more sparsely marked with black; color of pileum and hindneck more 

 reddish brown (mummy brown to chestnut-brown), the feathers often 

 with paler terminal small spots or streaks; all the rectrices, except 

 middle pair, with distinct white bars on both webs; under parts more 

 purely white (distinctly tinged with buff posteriorly only in fresh 

 autumnal plumage), the black markings on lower parts of body 

 broadly guttate, those on throat and chest but little larger (never 

 large and confluent as is often the case in other subspecies), but of 

 different (irregular and variable) form." 



William Brewster (1902) says of its haunts: "In the Cape Kegion 

 proper the St. Lucas Cactus Wren is everywhere a common resident 

 excepting on the higher mountains, where it appears to be wholly 

 wanting. Its favorite haunts are the arid, cactus-grown plains near 

 the coast and the almost equally barren and waterless foot-hills, but 

 at San Jose del Cabo Mr. Frazar found it abundant in gardens and 

 among shrubbery near or even directly over water." 



Grilling Bancroft (1930) says of its distribution in the central por- 

 tion of the peninsula: "These wrens, while common, are not nearly 

 so abundant as experience elsewhere would lead one to expect. It is 

 not easy to define their range because, in exceptional cases, they breed 

 among the palms of the oases as well as on the lava mesas. But in 

 general they limit themselves to areas of intermediate fertility, shun- 

 ning alike heavy undergrowth and associations of scant vegetation. 

 That leaves them the less rocky valley floors and most of the stream 

 beds as well as the narrowing canons and the lateral branches running 

 into the hills. The birds are appreciably more plentiful at the higher 

 altitudes." 



Nesting. — The same observer says of the nesting habits : 



In their choice of nesting sites the Cactus Wrens indulge in a wide I'ange of 

 individual preference. The most popular selection is the upper part of a cholla 

 or the center of a palo verde, but nests are not at all unusual in any low cactus, 

 in mesquite or other trees, in heavy mistletoe, in the crotches of sahuaros, or 

 within woodpecker holes. A formidable list could be made of unusual locations. 

 There is, with the exception of the lining, a marked uniformity in the construction 

 of the nests. Long fine grass stems are used as the basic material. These are 

 woven into gourd shaped structures fifteen to eighteen inches long with the 



