16 PACIFIC COAST AVIFAUNA No. 14 



oi-dinary meadows, witli many species of sedges (Carer) taking the ]ilaec of tiie 

 true grasses. In these areas the Savannah Sparrow, Chestnut-enllared Long- 

 spur and Sprague Pipit are cliaraeteristic. Where these areas l)()nl( !■ poiuls and 

 become somewhat marshy in character, the Wilson Phalarojie and scvei-al species 

 of ducks are liable to be found breeding. 



Benches (see fig. 2) are much dryer areas, chiefly found in the jirairie re- 

 gion but also to some extent in the mountain region at low elevations. While 

 these areas are mostly comprised in the flat-topped benches, they may be found 

 on rolling prairie lands or sides of hills, the dry soil and character of the vegeta- 

 tion being the factors that influence bird distribution rather than the flatness of 

 the ground. The grass on these areas is short, such species as gramma grass 

 {Boutcloua) predominating. The one definite, characteristic species of this asso- 

 ciation, throughout the state, is the Horned Lark. In the praine region the 

 McCown Longspur is also abundant in it, and in thinly settled regions the Up- 

 land Plover and Long-billed Curlew. 



Foothills occur mainly along the lower spurs of the mountains, in the Trans- 

 ition zone, and extend up to the limits of this zone on south slopes. The soil is 

 more moist than that of the benches, and the grasses are of taller species, such 

 as wheat grass (Agropyron) and bunch-grass (Aristicla). Many species of wild 

 flowers grow in this association, the most abundant and widel.y distributed being 

 blue lupine (Lupitius). The two most widely distributed and characteristic 

 breeding birds of this association are the Meadowlark and Vesper Sparrow. 



Water associations are peciiliar in that a large number of the species de 

 pendent on them are rare or local in distribution, and very few can definitely 

 be said to be found regularly in any given association. Five water associations 

 are easily recognizable, as found tiiroughout large parts of the state. They vary 

 considerably locall.y, but the general conditions of each one are about the same. 

 These five are prairie lakes, mountain lakes, rivers, mountain streams, and cat- 

 tail or tule marshes. 



Prairie lakes (see fig. 2) differ from mountain lakes not only in location but 

 also in the more significant fact that their borders are grass grown and without 

 trees. They are found mainly in the prairie region of the state and are most 

 abundant along the northei-n border. A large area of them in the southern part 

 of the state is comprised in the lake basin region near Billings. Th(!y are found 

 to some extent in the mountain region, even west of the divide, there being many 

 of them on the Flathead Indian Reservation in northern Jlissoula County. The 

 shores of these lakes form the breeding ground of large numbers of water birds, 

 such as grebes, gulls, ducks and avocets. Perhaps the only species that is widely 

 and universally enough distributed over the entire state to be thoroiighly charac- 

 teristic of this association is the Mallard. 



Mountain lakes are bodies of water in the Transition or Canadian zone of 

 the mountains, whose shores are bordered by evergreen foi'ests. These lakes are 

 also liable to have patches of willow thicket bordering their shores at the inlet 

 or outlet. They are generally glacial in origin and often very deep. They vary 

 greatly in size, Flathead Lake, the largest, being about thirty by fifteen miles 

 in extent, while small lakes of the same general character mav often he found 



