Riverine Habitat

Blitzen River

Rivers run through our history and folklore, and link us as a people. They nourish and refresh us and provide a home for dazzling varieties of fish and wildlife and trees and plants of every sort. We are a nation rich in rivers. 

~ Charles Kuralt

The major areas of riverine habitat on the Refuge are the Blitzen River and its tributaries (Mud and Bridge Creeks). Ideal riverine conditions exist when hydrologic floodplains are intact and when waterways support riparian communities that provide shade to maintain cooler water temperatures and are appropriate to stream channel type.

On the Refuge, the highest quality riverine habitat occurs at the south end of the Refuge in the unchannelized reaches of the Blitzen River and in the major tributary streams. A portion of lower Bridge Creek and 17.5 miles of the Blitzen River were channelized early in the 20th century prior to refuge acquisition, resulting in degraded riverine conditions through much of this portion of the Blitzen Valley. Although artificial, the East Canal from Page Dam to Bridge Creek provides attributes of riverine habitat and is in better condition than much of the Blitzen system. Below the confluence of Bridge Creek, where channelization begins, the river channel is deeply incised and does not support floodplain hydrology.

Within the past two decades, the Refuge has focused on improving fish passage through refuge dams and screening irrigation diversions to minimize loss of fish via irrigation diversion. Considerable effort has been applied to enhance stream-side riparian habitat in Bridge and Mud creeks and along the southern reach of the Blitzen River through plantings. Inverted weirs were installed in this reach of the river to raise the water table and increase habitat diversity in the natural channel.

Riverine habitats are prime habitat for redband trout, native suckers, sculpins, dace, whitefish, and native mollusks. This habitat is also important for Columbian spotted frogs, mergansers, belted kingfishers, river otters, and mink.