Main stem and off-channel habitat use by juvenile Chinook salmon in a sub-Arctic riverscape
January 4, 2019
- Poor growth and survival in freshwater and marine environments have been implicated as responsible for Chinook salmon (Oncorhynchus tshawytscha) declines across Alaska.
- Lateral connectivity of river main stems with off-channel habitats may play an integral role in sustaining Alaskan salmonid populations because off-channel habitats commonly provide greater growth opportunities than main stem habitats through greater macroinvertebrate productivity and warmer water temperatures. However, off-channel habitats may impose greater mortality risks to juvenile salmonids, as these habitats are typically more susceptible to drying and are often occupied by potential predators.
- We used a hierarchical Bayesian count model to describe juvenile Chinook salmon distributions throughout the Chena River, Alaska in main stem and off-channel habitats and employed diet, prey availability, and bioenergetic analyses to explain these habitat selection decisions from data collected in the summer of 2015.
- We found salmon to be most abundant in off-channel habitats as summer temperature increased, which suggested that salmon dispersed to off-channel habitats to take advantage of energetically favourable growth conditions as indicated by the higher prey biomass in benthic and diet samples collected within off-channel habitats.
- Our results could have significant implications for juvenile salmon under a warming Alaskan climate as access to productive off-channel habitats may be important to offset increased energetic costs as temperature warms.
Citation Information
| Publication Year | 2019 |
|---|---|
| Title | Main stem and off-channel habitat use by juvenile Chinook salmon in a sub-Arctic riverscape |
| DOI | 10.1111/fwb.13232 |
| Authors | Brock M. Huntsman, Jeffrey A. Falke |
| Publication Type | Article |
| Publication Subtype | Journal Article |
| Series Title | Freshwater Biology |
| Index ID | 70227788 |
| Record Source | USGS Publications Warehouse |
| USGS Organization | Coop Res Unit Seattle |