WHITE-RUMPED SHRIKE 155 



LANIUS LUDOVICIANUS EXCUBITORIDES Swainson 

 WHITE-RUMPED SHRIKE 

 HABITS 



This is the paler race of tlie species that is found in the western 

 plains of Canada and the United States, from the eastern border of 

 the Great Plains to the western edge of the Great Basin, and from 

 the plains of the Saskatchewan in Canada to the southwestern desert 

 regions and northern Mexico. 



Ridgway (1904) describes it as "similar to L. I. migr'ans^ but gray of 

 upper parts decidedly paler (between slate-gray and no. 6 gray), 

 changing abruptly to white on upper tail-coverts ; white of scapulars 

 more extended (occupying practically the whole of scapular region) 

 and more abruptly contrasted with gray of back; forehead and supra- 

 loral region paler gray than crown, sometimes whitish; under parts 

 purer white ; size averaging slightly larger." 

 Dr. Miller (1931) saj^s of its haunts in general : 



This race is found chiefly in arid, short grass or desert savanna, plains areas. 

 In these regions the original terrane is rarely modified by small farms. In the 

 north the range of this race includes some areas of more luxuriant grassland. 

 The birds forage out over the plains but usually they are to be found near the 

 timber, principally cottonwoods, along water courses. * * * in Texas the 

 race is found irregularly in regions where scattered oaks and mesquites occur. 

 Throughout its summer habitat excubitorides encounters comparatively arid con- 

 ditions with the exception of some northern parts of its range in Canada. 

 Life-zones occupied are Upper and Lower Sonoran, locally Transition in the 

 north. 



Between Quill Lake and Prince Albert, in northern Saskatchewan, I 

 saw a few white-rumped shrikes near the northern limit of their 

 summer range; the country here w\as rolling, largely open grassland, 

 but with scattered ponds, bogs, and muskegs in the hollows, and with 

 many groves of poplars or aspens on the highlands ; it was only thinly 

 settled with villages and small farms. 



I have no record of having seen it in southwestern Saskatchewan, 

 though it doubtless occurs there. 



Nesting. — In southern Arizona we found the white-rumped shrike to 

 be a very common bird and saw a number of their nests, as we drove 

 along the roads ; most of the nests were easily seen in the thorny bushes 

 by the roadside, usually not much more than 4 or 5 feet from the 

 ground. Along the road leading to the Chiricahua INIountains we 

 saw several nests in the soapweed yuccas ; one of these was a very pretty 

 nest, made of whitish weed stems with white cottony blossoms, giving 

 the nest a soft fluffy appearance; the six eggs in it were so heavily 

 incubated on April 26, 1922, that we did not collect it. But the next 

 day, near the Dragoon Mountains, we took a set of six perfectly fresh 



