[ ll ] BIRDSOFOREGON 



Rogue Rivers in Oregon. Both these streams rise on the western slope of 

 the Cascades and flow through the Coast Range in narrow rocky canyons. 



At the northwest corner of the State is the mouth of the Columbia 

 River, which is itself a huge bay. South along the coast are Nehalem 

 Bay, at the mouth of the Nehalem River; Tillamook Bay, which receives 

 the waters of five rivers (Miami, Kilchis, Wilson, Trask, and Tillamook) 

 and which has about its shores one of the two large areas of agricultural 

 land on the coastal slope; Netarts Bay, just south of Tillamook Bay, 

 small but highly important for bird life; Siletz Bay, at the mouth of the 

 Siletz River; Yaquina Bay; Alsea Bay; Coos Bay, the largest bay in the 

 State, with hundreds of miles of inlets and channels extending in all 

 directions from its central body; and the small bay found at the mouth 

 of the Rogue River. 



Inland about 100 miles from the mouth of the Columbia, which forms 

 the northern boundary of the State except for a small section in the north- 

 eastern corner, the Willamette River empties into the mighty river. It 

 rises in the central part of the State (north and south), where several 

 branches that flow from the Coast and Cascade Ranges unite near Eugene 

 to form the river. The valley formed by this stream is the largest area of 

 agricultural land in the western part of the State. It is well watered and 

 can be successfully farmed without irrigation. As a consequence it was 

 the promised land of the early emigrants and is now the most heavily 

 populated section of the State. Flowing northward from Eugene, the 

 Willamette gathers up the many streams that flow from the western slope 

 of the Cascades and the eastern slope of the Coast Range, making a 

 regular network of small waterways that profoundly affect the bird 

 population of the district. 



Just south of Eugene the Calapooya Mountains, a low cross range 

 between the Cascade and Coast Ranges, separate the headwaters of the 

 Willamette from the drainage of the Umpqua River. This latter stream 

 and its tributaries drain the western slope of the central Cascades from 

 south of Diamond Peak to Diamond Lake. Many of the tributaries and 

 much of the Umpqua itself are in narrow rocky canyons, but the valleys 

 of the main branches widen out in the vicinity of Roseburg to form a 

 considerable area of rich bottom land. 



The western slope of the Cascades from Crater Lake National Park 

 southward to the California line is drained by the Rogue, which is sepa- 

 rated from the Umpqua on the north by the Umpqua Mountains and from 

 the Klamath on the south by the Siskiyou Mountains that lie along the 

 Oregon-California line between the two major north and south ranges. 

 The valley of the Rogue also widens for a considerable distance to form 

 an extensive area of flat land and rolling foothills, which, because of its 

 similarity to California topography, furnishes many puzzling problems of 

 distribution between northern and southern geographical forms. 



