Coho salmon is a recreationally and commercially valuable fish whose habitat has been impacted by water storage, logging, urban development, and more. Climate change is expected to further alter Coho Salmon habitats by making their travel from sea to stream, as part of their spawning process, even more challenging. Droughts are also projected to worsen in the region, which may make it harder for Northwest streams to support salmon and other stream-dwelling fish. To prepare for these ongoing changes, natural resource managers are increasing interested in species management options that could protect the endangered Coho salmon. “Fish rescue” programs where fish are captured during times of seasonal environmental stress and reared in captivity until habitat conditions improve and they can be released back to their stream, have the potential to help fish cope with seasonal drought in streams. A study funded by the Northwest CASC modeled different fish rescue scenarios that can be viewed via a new interactive web application that allows users to better understand the different possible effects of fish rescue on Coho Salmon populations. Results from the study indicate that, although dependent on various conditions, fish rescues may be beneficial in increasing the abundance of returning adult fish when young fish are held in captivity for a full year. This research can help managers better evaluate if and when implementing a fish rescue program for vulnerable Coho salmon may be appropriate.

Read the Hakai Magazine piece on this paper here, and explore the web application associated with the study, here.