Page 26 - 2021PSF-ResilientCoastsForSalmon-NewLogo-Primer-Web

Photo by: Zac Gudakov on Unsplash

How Coastal Modification Impacts
Pacific Salmon
Coastal and estuarine areas, which are often
extensively developed with shoreline hardening Photo by: Shelter on Unsplash
and modifications in urban areas, are vital stop-over
habitats where young salmon grow, adjust and
prepare for their life at sea . Features such as
seawalls, riprap, docks, and piers, not only alter
how shorelines function, but they also affect
Pacific salmon during their coastal phase of life .
How well salmon grow during their time in coastal
areas is directly linked to their success out at sea,
and ultimately, whether they make it back to
spawn the next generation .
When Pacific salmon first migrate down to coastal
habitats, they preferentially use shallow areas
and shift along the depth gradient and between
habitats as they grow (Munsch et al . 2016) . Coastal
modifications, like seawalls that extend into the
lower subtidal zone, eliminate shallow areas and
complex habitat gradients . Shallow habitats are
particularly important for the smallest salmon as
they offer refuge from larger predators that cannot
access those areas . Without the shallow areas,
young salmon must occupy the same areas as
larger fish, leaving them more vulnerable .

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