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Adventure: Pinnipeds and Porpoises of the Salish Sea

Learn about harbor seals, sea lions, and harbor porpoises. Extra lucky days include dall's porpoise!

Guardians provides data on harbor porpoise and pinniped sightings to Pacific Mammal Research (PACMAM).  This data directly contributes to PACMAM's long-term study that provides a better understanding of life history, behavior, social structure and ecology.   It also helps the student participants build and cultivate a sense of stewardship, involvement and better understanding of the entire ecosystem in the Salish Sea. 

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Research: Pinniped & Harbor Porpoise Survey

Action: Stormwater & Water Quality

Water Quality: The foundation for all plants and animals that depend on the Salish Sea – from algae to fish to marine mammals.

The Salish Sea's ecosystem is reliant upon the quality of the water in which all of the life depends. Analysis of the water at set locations can help provide a better understanding of the source, cause, and location of any water quality degradation.

A variety of tools and equipment will be used by Guardians to measure and monitor water quality in the Salish Sea.  These are the same tools that local scientists and researchers are using, providing valuable experience with equipment and current research methods.

Water quality also affects people, at the beach, fishing, or digging clams, and indirectly when viewing the wildlife and scenery of the area.

The Salish Sea is unique in the lower 48 Unites States because of its fjord-like physiography, inland extent, wide range of depths, and urbanized watersheds and shorelines.

What is a pinniped? 


Pinniped means fin or flipper-footed and refers to the marine mammals that have front and rear flippers.


There are three families of pinnipeds: 

phocids "earless" (seals), 

otariids "eared" (sea lions),

and odobenids (walruses).

The following pinnipeds can be observed in the Salish Sea:

Phoca vitulina - Harbor Seal

Eumetopias jubatus - Steller Sea Lion

Zalophus californianus - California Sea Lion

Mirounga angustirostris - Northern Elephant Seal

What is a harbor porpoise?


The smallest of 22 cetaceans recorded in the Salish Sea. They are also probably one of the few that are year round residents.  

They weigh less than 100 kg (220 lbs) and are less than 2m (6 feet) long. Harbor porpoise will barely brush the water's surface as it comes up for air.

Photo courtesy of PACMAM

Degradation of water quality in the Salish Sea occurs through three primary mechanisms:

1. The first is through the introduction of toxic contaminants, primarily comprising manufactured synthetic chemicals, but also including compounds that occur naturally that are concentrated in the local environment to toxic levels via human activities.

2. The second is through human-caused changes in naturally occurring chemicals, compounds, or physical parameters (e.g., temperature, turbidity, nutrients, pH).

3. The third is through introduction of new diseases or pathogens, or through other activities that cause an unnatural increase in disease organisms.

Adapted from EPA's website on Marine Water Quality and the Encyclopedia of the Puget Sound.

Other interesting sources:
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