18 



PACIFIC COAST AVIFAUNA 



No. 14 



and mountain lakt'S. the Spotted Sandpiper, is atrain sure to be ])resent. The 

 true mountain stream has ))ut one eharaeteristie l)ird, the Dipper, and that hird 

 is souH'tiiiies absent if the stream is not clear. A second species i'ound iu this 

 association in a few k)calities is the Harlequin Duck. 



Cat-tail and tule nuirshesare not strictly water associations alone as they 

 take their character from the vegetation that grows in ihe water. Cat-tails and 

 tules really form two separate associations, but from the standpoint of bird distri- 

 i)ution they are about alike. These associations are marshes where the water is 

 fi'om a few inches to a foot deep, grown with either cat-tails or tules standing in 

 the water. The one most characteristic bird is the Red-winged Blaci\l)ird. Many 

 other species are also found in this association, though they are mon' or less local 

 in distribution. Grebes, the Black Tern, a few species of dnck's. th" Coot, Sora, 

 Uittt-rn. Marsh llawk, Ycllow-lieadcd P>la<'l<bird and Marsh Wren arc all liable 



Fig. 4. On thk Sux Rivkk, Lkwis a.nu Ci.akk Cou.my; Ji lv, 1!)12. A 



MOUNTAIN STKKAM AND SI'RUCl': FOKEST OF TIIK CANADIAN ZONE 1\ 

 THE FOREGROUND AND MOUNTAINS KXTKXDlNd TO THE HUDSONIAN 

 ZONE IN THE DISTANCE. 



to be I'ound nesting amid such surroundings. As far as my observations go, it 

 has appeared thai the Rrd-wiuged Blackbird prefers cat-tails, and the Yellow- 

 headed, tules. l'erhai)s two associations should be recognized on account of this 

 l)i-eference on the pai't of Two characteristic species; but until more definite ob- 

 servations are madf it would be better to keep them together. 



Rock associations ()ccui)y compai'atively suudl areas, but, they definitely de- 

 termine the disti-il)ution of a few species. These associations differ eonsideral)ly 

 iu different parts of tiie state, and a1 different elevations in the mountains, rang- 

 ing from the badlands in the eastern prairies to glacial moraines lud i)recipitons 

 mountain sides in the Alpine-Arctic /one. (See fig. 0.) But the distinctions 



