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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

Close-up of a shark partially submerged in water, showcasing its dorsal fin and textured, spotted skin.

Puget Sound researchers uncover shark secrets, but new questions arise

Recent discoveries of two new shark species in Puget Sound have sparked public interest and may encourage greater conservation efforts. In this seven-part series, Christopher Dunagan provides an overview of sharks in Puget Sound and some of the recent work among scientists to protect these often misunderstood creatures.

View of a shark swimming underwater above rocks.

Discovery of soupfin shark surprises researchers

Soupfin sharks were not known to occur in Puget Sound until one was hooked by a fisherman in 2022. Scientists say warming oceans from a changing climate may be bringing more of the species into local waters. Our series on the sharks of Puget Sound continues with a closer look at soupfins and why they are being considered for inclusion on the Endangered Species List.

A large grey shark swimming against a dark background above seapens attached to a rock.

Is Puget Sound a nursery for sixgill sharks?

Bluntnose sixgill sharks are among the largest sharks in the world, reaching lengths of almost 16 feet. Research shows that Puget Sound may be an important place for sixgills to give birth and raise their young. We continue with part three of our series on Puget Sound's sharks.