Two new shark species are moving into Puget Sound: ‘They’re not supposed to be here’

SEATTLE – There’s a new pair of apex predators in Puget Sound.

Two species of shark, one of which is critically endangered in some places, have been found in South Puget Sound, sparking a bit of mystery surrounding the region’s marine habitat, scientists with Oregon State University said.

What brought them to these waters? Have some of them been here all along? Could climate change be a factor?

Everything started with a single social media post.

Sharks already live in Puget Sound (and shark attacks are exceptionally rare), said Jessica Schulte and Ethan Personius, scientists with Oregon State. Spiny dogfish and sixgill sharks are well documented throughout the waters. The latter are heavily protected by state officials and cannot be harvested.

So, several years ago, when one man in South Puget Sound posted a photograph of himself holding a shark appearing to be a sixgill, officials investigated, Schulte said. As it so happened, though, the man was not holding a sixgill, but actually a broadnose sevengill shark.

“That was crazy,” Schulte said. “Because they’re not supposed to be here.”

Schulte, Personius and officials from the National Oceanic and Atmospheric Administration and the Washington Department of Fish and Wildlife banded together for a fact-finding mission.

Sevengill sharks earned their moniker because they have more gill slits – seven instead of five – than most other species and they can grow to nearly 10 feet. Only one of the species had been confirmed in the area, Schulte said, and that capture took place decades ago, nearly 200 miles away near Point Roberts, off the Canadian border.

These species can be found off the Washington coast, Schulte said, but finding them in Puget Sound, particularly in the southern region, is remarkable.

The fisherman behind the social media post told scientists he had been catching sevengills for a couple of years, Schulte said. Lo and behold, on their first outing to confirm his claims, they found several of them as well.

Last year and in 2022, the scientists caught nine sevengills in South Puget Sound, near Olympia, Schulte said. Eight of them were male, measuring under 7 feet and the female was about 4½ feet long.

The fisherman also showed them photos of another species of shark he had caught, one that Personius identified as a soupfin shark.

Soupfin sharks were once quite numerous on coastal waters, Personius said. They were highly prized for their fins – used in the eponymous shark fin soup – and for their livers.

Because they were so valuable, the soupfins sparked a type of “gold rush,” Personius said. And they were fished to near extinction in the coastal waters.

Not only have the waters of Puget Sound been heavily fished over the generations but they’ve also been heavily studied, Personius said. And never before had a soupfin shark been documented within the Sound.

One day, as the scientists searched the South Sound for a sevengill shark, the conversation turned to the elusive soupfin, Personius said. As luck would have it, that day they happened to pull one out of the water.

It was a male, measuring just more than 5 feet.

Not only is finding a new species in Puget Sound notable, Personius said but it’s also a reason to figure out why they might be in the area.

One reason could be rising marine temperatures, he said.

Soupfin sharks often feed on anchovies, Personius said. Anchovies are becoming more common in the Salish Sea, with their populations particularly spiking after the 2014 and 2015 marine heat wave colloquially known as the Blob.

But there could be other reasons why these sharks moved into the area or why they hadn’t been documented before, he said.

As the scientists pulled the sharks out of the Sound, they tagged them with locators to try to track their movements, Schulte said. They can recapture them at different times and flush their stomachs to see what they’re eating to learn more.

“It’s quite smelly, but it’s quite rewarding,” Schulte said.

Marine heat waves are predicted to become more common and severe as climate change worsens. The Blob caused massive die-offs of coastal birds and crabs, among other species. The warming ocean temperatures also pose a threat to salmon.

Other species, however, flourish in the warmer aquatic temperatures.

Additional research into the appearance of the sevengill and soupfin sharks is needed to find out whether new suitable habitat is being created in which they might live and thrive, Personius said. And if the species are becoming more common here, fisheries should take precautions.