About the Puget Sound Institute

Habitats
Nearshore environments
Section author: Richard Strickland, University of Washington School of Oceanography
This document focuses on the physical and geological conditions in the nearshore environment
of Puget Sound. The nearshore environment extends from the head of tide and the upper edge of
coastal bluffs seaward to the offshore limit of the photic zone (Shipman 2008). The boundaries
described in this section represent the broader definition of the Puget Sound watershed,
including the Strait of Juan de Fuca or the San Juan Islands.
Puget Sound covers approximately 8,000 km 2 (2 million acres) and has 4,020
kilometers (2,500 miles) of shoreline (Gelfenbaum et al., 2006). It receives
runoff from a 36,000 km 2 (8.3 million acres) watershed that includes 16 major
rivers (Fresh et al., 2011; Cereghino et al., 2012).
The Puget Sound Nearshore Ecosystem Restoration Project (PSNERP), a major collaborative
effort, examined the extent and condition of several categories of shoreform (Shipman, 2008;
Fresh et al., 2011) in the Puget Sound nearshore environment: 1) rocky platform and pocket
beaches; 2) two beach types: bluff-backed beaches and barrier beaches; 3) four embayment
types: barrier estuaries, barrier lagoons, closed lagoons/marshes, and open coastal inlets; and 4)
large river deltas.
This report focuses on the value, extent, and condition of beach and embayment shoreforms.
Large river deltas are discussed in a separate report. Overall, Puget Sound’s shoreforms have
experienced a large degree of alteration since the mid-19 th century, the baseline for comparison.
1. The nearshore environment of Puget Sound provides habitat for 211 fish species, 100
species of sea birds, and 13 marine mammals (Cereghino et al., 2012).
a. It includes critical habitats such as coastal forests, spawning beaches for forage
fish (such as surf smelt), eelgrass beds, and salt marshes, all of which shape the
health of salmon populations (Johannessen & MacLennan, 2007).
2. The shoreline of Puget Sound has become shorter and simpler since the first surveys in
the last half of the 19 th Century, and the vast majority of the changes are due to human
alterations (Fresh et al., 2011).
a. The net decline in shoreline length over all of the Sound has been 694 km or
about 15% of the historical length of the shoreline (Fresh et al., 2011; Simenstad
et al., 2011; Schlenger et al., 2011).
b. More than 1,000 km of natural shoreline were lost and 368 km of artificial
shoreline were added (Fresh et al., 2011).
3. Forty percent of the shoreline of Puget Sound has been altered by (Fresh et al., 2011) one
or more of the following “stressors:” Armoring, nearshore fill, tidal barriers, marinas,
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