Greene, C., Beamer, E., Chamberlin, J., Hood, G., Davis, M., Larsen, K., Anderson, J., Henderson, R., Hall, J., Pouley, M., Zackey, T., Hodgson, S., Ellings, C. and Woo, I., 2020. Landscape, density-dependent, and bioenergetic influences upon Chinook salmon in tidal delta habitats: Comparison of four Puget Sound estuaries. Northwest Fisheries Science Center, Seattle, WA. pp. 136.

While it is well appreciated that juvenile
Chinook salmon rely on estuaries for rearing
during juvenile migration, several information
gaps hamper effective science-based restoration
and population recovery. To address these gaps,
biologists and managers have generally
proceeded in a geographically circumscribed
framework, with the common refrain that “this
is what Chinook do in our system.”
With the goal of developing general biological
principles characterizing rearing conditions for
natural-origin juvenile Chinook that apply to a
variety of estuaries, we examined fish-habitat
relationships in four representative tidal river
deltas of Puget Sound: the Nooksack, Skagit,
Snohomish, and Nisqually (Fig. 1). The selected
systems vary in landscape features and
outmigrant population attributes (e.g.,
proportion of natural-origin vs. hatchery-origin
juveniles), and thus represent the diverse
characteristics we might expect in estuarine
systems inhabited by juvenile Chinook across a
broad geographic range within and beyond
Puget Sound.
We address three issues: how does landscape structure affect juvenile Chinook salmon
distribution and abundance in tidal deltas, how common are habitat limitations (i.e., density
dependence), and under what conditions do fish experience growth variability and food
limitation in delta wetlands?