COMMON ROCK WREN 285 



species as the horned lark and the song sparrow. One reason for this 

 is that its specialized habitat is remarkably uniform, as to sunshine 

 and shadow and as to aridity and humidity, throughout its \^ide range. 



An ornithologist is sometimes asked by a beginner where to look 

 for birds; the answer is simple, almost anywhere and everywhere, 

 for there are few places on this earth where we may not hope to find 

 some species of bird. There are, of course, more species of birds and 

 more individuals in fertile, well-watered temperate and tropical re- 

 gions, but the places that seem to us most forbidding are seldom 

 wholly birdless. The raven survives the long winter night on the 

 icy shores of Greenland; the pipit and the rosy finches retire to the 

 barren mountaintops to breed above timberline; the desert race of 

 the horned lark lives on the bare, sun-baked, sandy plains of the south- 

 western deserts, where not another living thing appears ; and the rock 

 wren makes a living in the hardly less inviting rocky barrens of the 

 badlands. Probably these birds have been crowded out of more fav- 

 orable environment where competition was too keen and have learned 

 to adapt themselves to new conditions and make a living where the 

 food supply is scanty but sufficient for their needs. 



During the breeding season, and largely at other times of the year, 

 rock wrens confine their activities to bare, open, wind-swept, sunny, 

 rocky surfaces, either steep or gently sloping, in valleys, foothills, 

 or wide canyons, where there are piles of broken rocks or scattered 

 boulders and generally little or no vegetation. On the open plains of 

 Cochise County, Ariz., we found them in the dry, rocky arroyos and 

 on the open slopes entirely destitute of rocks, where the clayey soil, 

 baker hard by the hot, glaring sun, had been cut into miniature can- 

 yons 6 to 10 feet deep by the heavy rushing torrents of the previous 

 rainy season. 



Limestone quarries are favorite resorts, and the cliffs and caves of 

 the deep>er canyons are sometimes invaded, close to the haunts of the 

 canyon wrens. Where suitable rocky environment can be found, they 

 range upward in the mountains to 8,000 or 10,000 feet. Fred Mallery 

 Packard tells me that, in the Kocky Mountain National Park, Colo., 

 rock wrens are fairly common summer residents, arriving "at the park 

 boundaries in mid-April, some continuing their migration to timber- 

 line nesting sites. They nest late in May and in June, the harsh song 

 continuing until mid-July, and occasionally it may be heard in August. 

 There may be some vertical wandering in summer, when a few have 

 been seen above timberline. The descent from the mountains begins 

 about August 20, and by the end of September they have left the 

 park." 



Mrs. Bailey (1902) draws the following pen picture of the rock 

 wren in its haunts: '■'■Salpinctes ! To the worker in the arid regions 

 of the west this name calls up most grateful memories. On the wind- 



