The role of estuaries in the ecology of juvenile Pacific salmon and trout in Puget Sound
This overview describes the different ways that juvenile Pacific salmon and trout use estuaries, and why those differences are important for ecosystem recovery efforts. The report was commissioned by the University of Washington Puget Sound Institute with funding from the Environmental Protection Agency's National Estuary Program.
Summary
Each year, eight different species of salmon and trout migrate downstream and into Puget Sound and other parts of the Salish Sea. These species vary in their size and age upon entering Puget Sound, and their use of estuaries and other nearshore marine habitats also varies. These differences in use of estuaries are important parts of their basic ecology and they make some species more susceptible than others to natural and human-caused variation in habitat availability and quality. This review provides concise (but not exhaustive) information on the timing of downstream migration by the different salmon and trout species, how long they stay in estuaries, and how they use them. It provides 1) a conceptual background on variation in migration, 2) information on how we obtain information about the use of estuaries by fishes, and 3) the overall ecological role of estuaries for salmon of all species. After that introductory material, the body of the review is organized by species to facilitate access by readers to information that might be of special interest. It ends with concluding thoughts on the overall reliance of salmonids on estuaries as they have been altered and can be restored.
