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A red boathouse extends from a wooden pier over calm, misty waters with forested shorelines under an overcast sky.

Researchers zero in on low-oxygen areas of concern in Puget Sound

Low dissolved oxygen levels put aquatic life in Puget Sound at risk – but not everywhere. A combination of careful monitoring efforts and powerful computer models are now enabling scientists to identify which areas of our regional waters are most prone to low oxygen levels, when, and why. This article is part of a series of reports funded by King County about the quest to define healthy oxygen

A researcher in red clothing aboard a "CETACEAN RESEARCH & RESPONSE" boat monitoring an orca swimming nearby in sparkling blue waters with forested coastline in the background.

Research and whale watching enhanced with artificial intelligence to identify individual orcas

Artificial intelligence is emerging as a powerful new tool for whale identification. New software can be adapted and used to identify any animal with a dorsal fin on its back.

: A beaver emerges from a wire trap cage surrounded by tall reeds and wetland vegetation.

The secret legacy of tidal beavers

Beavers are typically associated with freshwater environments, but scientists have learned that they also survive and thrive in the shoreline marshes of the Salish Sea. New research is shedding light on the vital connection between tidal beavers and salmon.

Aerial view of an algal bloom in Puget Sound.

'Natural conditions' are at the center of disputes over dissolved oxygen standards

Oxygen is indisputably essential to aquatic life, but conflicts are brewing over water quality standards mandated in state regulations. This article is part of a series of reports funded by King County about the quest to define healthy oxygen levels in Puget Sound. By some estimates, those definitions could affect billions of dollars in state and local spending. [Editor's note: King County is

Underwater view of many fish swimming in one direction.

Abundance of pink salmon may be harming orcas

Pink salmon now comprise nearly 80 percent of all adult salmon in the North Pacific. This record abundance is coming at a cost to other salmon species such as threatened Chinook, which compete with pinks for spawning territory. A new study shows that the ecological toll may extend all the way to endangered southern resident killer whales.

River otters on a dock in Puget Sound

Marine-foraging river otters in the Salish Sea

While not true marine mammals, river otters do use and rely on marine resources. The expansion of their populations since the early 1900s is a true conservation success story. Ecosystem recovery efforts and river otter reintroductions restored otter populations to much of their historic range. River otters often live in small social groups that include mother and offspring or other unrelated

The image shows an orca swimming near a sailboat. The whale's black and white coloration and large dorsal fin are visible as it surfaces from the water. In the background, a sailboat with passengers can be seen.

New buffer zones could help orcas hear their dinner

Just last year, scientists published the first direct evidence that noise interferes with orca feeding behavior. Officials hope a new law establishing a larger buffer zone between boats and endangered southern resident orcas will mean quieter seas and healthier whales.

Two dolphins leaping out of the ocean water. Their streamlined grey and white bodies are clearly visible as they break through the blue, wave-patterned surface.

Common dolphins in the Salish Sea

The appropriately named common dolphin is probably the most abundant cetacean on the planet. Common dolphins occur in most of the world’s tropical and temperate waters. Historically, they have not been common in inshore waters in Puget Sound and the Salish Sea but they are becoming more frequent as water temperatures warm.

A minke whale with its mouth open as it surfaces.

Minke whales in the Salish Sea

Minke whales are the most abundant baleen whale species worldwide. In the waters of the west coast of North America, their populations have remained small, but stable over time. They are hunted by transient killer whales due to their relatively small size compared with other baleen whales. Sighting rates for minke whales in the Salish Sea are highest during the summer, however, little is known

Two people kayaking during sunset over a calm body of water, with driftwood scattered on the beach in the foreground and the sillouette of land in the distance.

Puget Sound Marine Waters 2023 Overview

Each year, the Puget Sound Ecosystem Monitoring Program releases the annual Puget Sound Marine Waters Overview report. The latest report combines a wealth of data from comprehensive monitoring programs and provides a concise summary of what was happening in Puget Sound’s marine waters during 2023. The report represents the collective effort of 67 contributors from federal, tribal, state, and local