Salish Sea ecosystem health

One of PBI’s focal areas has been monitoring species population status and ecosystem health in the marine environment of the Pacific Northwest of North America.

The Salish Sea ecosystem is one of the greatest natural assets of Washington State and neighboring British Columbia.  The health of the Salish Sea is integral to the health of the regional economy and to the coastal communities around its perimeter.  

Three hundred years ago, the Salish Sea was brimming with life and was one of the most productive and diverse marine ecosystems in the world. It sustained indigenous people at a higher population density than most other parts of North America.  

Overfishing, by-catch, pollution, dredging, and coastal development have significantly altered this ecosystem over the last 200 years.  Efforts to reduce these stressors in the last few decades have shown some positive results. But the additional stress of warming oceans and ocean acidification by high levels of anthropogenic CO2 emissions now create perhaps the most severe long-term threat to the Salish Sea ecosystem.  The effects of climate change and ocean acidification on marine biodiversity are complex and hard to predict.

Early warning systems for biodiversity

PBI’s research contributes to the growing body of knowledge of the effects of anthropogenic stressors on the Salish Sea. We have demonstrated that the harbor porpoise Phocoena phocoena is a useful and easily observed sentinel species for Salish Sea ecosystem health.  Together with partner organizations and volunteer citizen scientists, we’re considering how to develop an “early warning system for biodiversity” with more indicators of marine ecosystem health, to track the health of the Salish Sea.

Our citizen science observation network may expand to include work on other marine mammals, sea and shore birds, and forage fish. Birds will include: great blue heron, marbled murrelet, several grebe species, gulls, kingfishers, and bald eagles. The forage fish species include herring, sand lance and smelt.

PBI will use our long-term sight observations and underwater acoustic information on the harbor porpoise to explore links to changes in greenhouse gas concentrations, marine pH, increasing thermal stress, and other factors such as noise, fishing, and habitat alteration. An early warning system will help us respond intelligently to mitigate the impacts of environmental threats to the Salish Sea ecosystem.

PBI’s highly successful Harbor Porpoise Project has changed a species that was “too difficult to monitor,” to one recognized as a sentinel species for Salish Sea ecosystem health. We did this by using two metrics: land-based observations and acoustic detection. Our strong citizen science program trains volunteers to work with scientists to collect observation data, and six underwater monitor buoys collect continuous acoustic data. These two metrics independently demonstrated that harbor porpoises have declined significantly at our primary research site in only four years.

The Salish Sea ecosystem is complex and interrelated. We will work with a wide variety of partners to better understand the complex interrelationships critical to ecosystem health.

For more information about the Harbor Porpoise Project, our research results, methods and volunteer resources, visit our Harbor Porpoise page. Click here for current events and activities. Please support our work in the Salish Sea via the Donate button!