Effects of a novel fish transport system on the health of adult fall Chinook salmon

Movement past hydroelectric dams and related in-river structures has important implications for habitat connectivity and population persistence in migratory fish. A major problem is that many of these structures lack effective fish passage facilities, which can fragment spawning and rearing areas and negatively impact recruitment. While traditional fish passage facilities (e.g., ladders, trap and haul) can effectively enable fish to pass over barriers, their capital or operational costs can be significant. We evaluated the utility of a novel transport device that utilizes a flexible tube with differential internal air pressure to pass fish around in-river barriers. A total of N = 147 adult fall Chinook salmon (Oncorhynchus tshawytscha) nearing maturation were apportioned to three treatments and a control group. In two of the treatments, adult fall Chinook salmon were transported through the device via two lengths of tube (12 or 77 m) and their injury, stress, and immune system respon...