Harmful algal blooms

In July, the recent trends of warm, dry conditions lessened; however, river flows remain low. Extensive macroalgae drifted through South and Central Sound and washed up on beaches. Macroalgae growth is fueled by excessive nutrients and sunshine. When it washes onto the beach, it is called beach wrack, and it can be a health risk to beachgoers because of bacteria it can harbor. From our aerial photography, we saw that Southern Hood Canal looks tropical because of a bloom of coccolithophores coloring the water turquoise. Schools of fish congregate in South Sound and southern Hood Canal. Jellyfish are abundant in Quartermaster Harbor.

A 2019 paper in the Journal of Geophysical Research: Oceans outlines how the Salish Sea Model describes the impacts of climate change, sea level rise and nutrient loads on the region's nearshore environment.

LiveOcean is a computer model simulating ocean water properties in Puget Sound and the Pacific Northwest. It is produced by the University of Washington Ocean Modeling Group and makes three-day forecasts of currents, temperature, salinity and many biogeochemical fields including harmful algal blooms.

Chemicals, disease and other stressors can increase a salmon's chance of being eaten or reduce its ability to catch food. We wrap up our series on the Salish Sea Marine Survival Project with a look at some of the lesser-known, but still significant factors contributing to salmon declines in the Salish Sea.

As the region's population grows, scientists say we can expect to see increasing amounts of nitrogen and other elements flowing into Puget Sound. Known as “nutrients” these elements are naturally occurring and even necessary for life, but officials worry that nutrients from wastewater and other human sources are tipping the balance. That could mean big problems for fish and other marine life, gradually depleting the water of oxygen and altering the food web.

A regional sewage-treatment system in Thurston County has helped contain  low-oxygen problems in Budd Inlet as the population continues to grow. The system cleans up some of the effluent for replenishing groundwater supplies.