Jurassic shark: Scientists find ancient species in Puget Sound

Scientists have documented two species of shark in Puget Sound for the first time.

The two discoveries, each newly published in the journal "Frontiers in Marine Science," began when a recreational fisherman posted a selfie with a shark he had caught in 2021.

Wildlife officials saw his photo and thought at first it was a sixgill shark, one of the world’s most widespread shark species, though rare and illegal to catch in Washington waters. A closer look revealed it was a species that had never been documented in Puget Sound: a broadnose sevengill shark.

Sevengills are among the most ancient of sharks, dating back to the Jurassic Period nearly 200 million years ago. Most sharks evolved more recently and have just five gills.

Sevengill sharks cruise along the sea floor to hunt octopuses, fishes, and other sharks and have been seen hunting seals in packs, according to the Monterey Bay Aquarium. They have speckled backs and creamy bellies and grow up to 10 feet long.

Scientists knew they swim the outer coasts of Washington and Oregon, but not Puget Sound.

“They were around back when the dinosaurs were around,” said Oregon State University graduate student Jess Schulte, who studies sevengill sharks in Washington’s Willapa Bay. “They're virtually unchanged since then, so they're a pretty cool animal.”

The fisherman claimed to have caught 10 sevengills in the previous two years in South Puget Sound.

Shark researchers decided to look for themselves.

A team of scientists headed out to Hammersley Inlet, near Shelton and the far southern end of Puget Sound, nearly a 200-mile swim from the outer coast.

“We really didn't expect to find much,” Schulte said. “And then on the very first day, we caught multiple sevengill sharks. So we were incredibly surprised.”

Schulte said the team, angling from a research vessel, has hooked 13 sevengills over the past three years, each of them examined alongside the boat so water would keep flowing over their gills. Researchers tagged each animal at the base of the dorsal fin with a brightly colored plastic tag shaped like a piece of spaghetti, then set the shark free.

“It's basically like an ear piercing on the outside of the shark,” Schulte said.

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Later that summer, the researchers returned to Hammersley Inlet and were stunned to find another unexpected species: a 5-foot-long adult male with an unfortunate common name—the soupfin shark, also known as the tope shark.

The International Union for Conservation of Nature lists the species as "critically endangered."

“They're incredibly rare to find basically anywhere on the Pacific coast,” Schulte said.

Or so researchers thought.

They contacted the sevengill shark fisherman, and he said he’d caught and eaten at least six of the soupfin sharks in Hammersley Inlet since 2021.

Soupfin shark livers contain the highest concentration of Vitamin A of any fish on the West Coast, according to Canada’s Committee on the Status of Endangered Wildlife in Canada.

A brief but aggressive fishery from 1937 through the 1940s—when supplies of cod liver oil from Europe were cut off—killed 800,000 of the soupfins, badly depleting their populations from California to Canada.

In 2022, activists with the Center for Biological Diversity petitioned the U.S. government to protect the soupfin shark under the Endangered Species Act.

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In June 2024, the center sued the National Oceanic and Atmospheric Administration after the agency missed its deadline for taking action on the soupfin shark petition.

While some people might not relish news of more sharks in Puget Sound, Schulte said they are key parts of a functioning ecosystem.

“Shark interactions of any sort are incredibly rare, and so no one needs to be worried about having any,” Schulte said.

Why these sharks have only recently turned up in South Puget Sound is unknown. They could reflect and, as top predators, shape a changing roster of species beneath the surface.

Schulte says warmer waters or growing populations of harbor seals might have lured the sharks to new feeding grounds.

The recent findings bring the number of known shark species in Puget Sound to 11.

“Sharks have been in Puget Sound for millions of years. They are a sustained presence and a sign of a healthy ecosystem there,” Schulte said.