A CACTUS DESERT AND ITS BIRD-LIFE 



THE great cactus-covered deserts, so characteristic of the more 

 arid portions of Mexico, push a well-developed arm northward 

 into Arizona, forming too marked a feature of North i\merican 

 scenery to be omitted from any series of representations designed to 

 include at least the more pronounced types of our landscape. 



Since this region has no colonies of birds and no one bird of sufficient 

 size to be treated alone, it was decided to prepare a group which should 

 show its common l)irds as well as its commoner forms of vegetation. 



Tucson, in southern Arizona, was selected as a suitable locality for 

 our studies, throughout which we had the invaluable advice of Dr. 

 D. T. MacDougal, Director of the Desert Botanical Laboratory of the 

 Carnegie Institution, which is situated at this point. 



At the time {^Nlay 9-20, 1906) of our visit the desert vegetation was at 

 its best, and looking out over the variously colored blossoms it was 

 difficult to believe that we were not in a land of great fertility. 



The birds of this region, like its plants, are of Mexican origin. Along 

 the "washes," which after rains in the mountains are streams for a 

 brief period, mesquites and acacias grow abundantly, and here such 

 brighdy colored birds as Cardinals and Vermilion Flycatchers are found. 

 Where this irregular but natural type of irrigation is lacking, the vegeta- 

 tion is chiefly of cactus which, affording but litde shelter for birds of 

 bright colors, is inhabited chiefly by species of neutral-tinted plumage. 



Here Mockingbirds and Thrashers (chiefly Toxosioma curvirostre 

 pahneri), Cactus Wrens, Roadrunners, Gambel's and Scaled Quail, 

 Texas Nighthawks, Inca, W'hite-winged,^and Mourning Doves, Black- 

 throated Sparrows, Gilded Flickers and Crested Flycatchers {Mijiar- 

 chus) nested in the giant cacti. 



The making of the vegetation for this group called for unlimited 

 skill and patience on the part of the preparator. Every joint of cactus 

 shown is a facsimile reproduction of the original. Before making the 

 plaster molds, every one of the hundreds of spines was carefully re- 

 moved. After the casts had been taken from the mold (the Opuntia 

 in wax, the others in plaster) they were colored from field studies of 

 growing plants, and the original spines were then set in their proper 

 positions. 



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