Restoration of Patterson Big Springs Creek: A Lesson in Habitat Connectivity for Chinook Salmon (Oncorhynchus tshawytscha) in the Upper Salmon River Basin of Idaho

The Upper Salmon River Basin is designated as critical habitat for Snake River spring / summer Chinook salmon (Oncorhynchus tshawytscha) and historically supported excellent spawning and rearing habitat for anadromous salmonids. However, over the past century Chinook salmon access to spawning and rearing habitat has been severely limited due to anthropogenic barriers and low flows during irrigation season.  Conservation efforts have focused on improving egg to smolt survival by addressing fish entrainment into irrigation ditches, eliminating fish passage barriers, and restoring instream flows.  Patterson Big Springs Creek is an example where barrier removal has provided access into historically utilized Chinook salmon spawning and early rearing habitat.  Adult Chinook salmon were observed upstream of the former barrier the first year it was removed and juvenile Chinook were documented the following summer.  In 2014, a total of 117 adult Chinook salmon redds were documented utilizing the newly accessible habitat yielding an estimated 20.9 redds per km. The story of restoration of Chinook salmon in this creek is still being told. The ongoing effort is largely due to the collaborative efforts of private landowners, Idaho Department of Fish and Game’s (IDFG) Anadromous Fish Screens, Passage, and Habitat Program, and multiple conservation partners.