Keywords: Fishes, Salish Sea Currents magazine, Species of concern

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.    


It was during the second shark-fishing trip to Hammersley Inlet on July 7, 2022, that the shark researchers reeled in a five-foot shark with a sharper nose than a sevengill. This shark looked more streamlined; it was not spotted; and the dorsal fin on its back was much closer to its head than seen in the sevengills.

One member of the research team, Ethan Personius, another grad student at OSU’s Big Fish Lab, had been studying this very species —the soupfin shark — in Willapa Bay on Washington’s coast. Personius had heard that Connor Seifert may have been catching one or more soupfins nearby, so he was surprised, but not shocked, when the soupfin was caught.

“We had a slow start to that day, catching only three or four spiny dogfish before we got the Soupie,” Personius recalled. “Although we had talked about the possibility of a soupfin capture earlier that morning, we were a bit surprised to see one come up on the line. They have a large slender snout and an unmistakable caudal fin (the tail), so we were immediately sure that it was a Soupfin.

A soupfin shark captured in South Puget Sound (left). Researchers Kate Olson (WDFW),  Dayv Lowry (NOAA), and Ethan Personius (OSU) measure and sample the shark before returning it to the water (right). Photos: (Top left) Dayv Lowry/NOAA ; (bottom left) Maddie English/OSU; and (right) Jessica Schulte/OSU.

“There was quite a bit of excitement on the boat,” he continued, “as not more than a few months after the sevengill confirmation, we had just confirmed the presence of another (unknown) shark species in Puget Sound.”

Until that time, the closest official reports of soupfins came from the Strait of Georgia on the Canadian side of the border in the Salish Sea, where two of the sharks washed up dead in 2016. About that same time, a commercial fisherman in Canada also reported a single catch.

“Soupfins are kind of like the new kids on the block for the Salish Sea,” Personius noted. “They are pickier eaters and a lot harder to catch than sevengills.”

Personius grew up in Hawaii and became interested in marine science at a young age. As a student at The Evergreen State College in Olympia, he took an internship at Chapple’s Big Fish Lab and began studying broadnose sevengill sharks for his undergraduate thesis. After graduating from Evergreen in 2022, he became an OSU student and was officially part of the lab while pursuing a doctoral degree in fisheries science.

Although both sevengills and soupfins are considered opportunistic feeders, it is not clear if they are pursuing the same prey or if each species has its own priorities, Personius said.

“It would be nice to know if these two species have the same drivers (in the food web), but they could be very different,” he added.

Three people wearing safety gear on a boat examine a shark lying on a net.

From left, Lauren Horstmyer, Maddie English and Ethan Personius with the first soupfin shark documented in Puget Sound. Photo by Joshua Bowman/OSU. (CC BY-SA 2.0)

Along the West Coast of North America, sevengill sharks are generally larger than soupfins, with some of the larger sevengill males reaching eight feet and females approaching 10 feet. That compares to smaller soupfins at up to six feet for males and seven feet for females.

As with sevengill sharks, the perplexing question for soupfins is: Were these sharks living in South Puget Sound all along, somehow avoiding capture, or did they recently move in, perhaps to take advantage of changing environmental conditions? An initial discussion is provided in the new report by Personius and fellow researchers in the journal Frontiers in Marine Science.

As the paper states, “It is conceivable that our observations of the soupfin shark in South Puget Sound represents the initial detection of an established but cryptic population of this highly mobile species within the Salish Sea. However, we find this scenario unlikely.”

If present in Puget Sound, these sharks must have escaped capture for many years in sport and commercial fisheries that employed not only hook-and-line gear but also deep-water trawl nets and gillnets used in salmon fishing, the paper explains. Elsewhere in the world, these methods are used successfully to catch this species. Furthermore, soupfins were never seen on video recordings taken by submersible drones during extensive underwater surveys of the Salish Sea.

Consequently, the researchers are suggesting that soupfins probably moved into South Puget Sound as the result of changing conditions that led to warmer waters with observable alterations in the community of prey species.

“For example,” the authors say, “over the past century, the Salish Sea forage fish community has been dominated by Pacific herring, Pacific sand lance, surf smelt and other smelt species…” During this period, intermittent increases in water temperature have been known to create spikes in the abundance of anchovies, which also contribute to the food supply for larger species.

“The most recent significant spike in anchovy abundance in the Salish Sea began around 2014, aligning with a period of elevated sea surface temperatures in the region, simultaneous with the increase in anecdotal reports of soupfin sharks by recreational fishers, which prompted this investigation.”

Based on the latest genetic information, soupfins along the West Coast — ranging from British Columbia to Mexico — are considered a single, highly migratory population, somewhat separate from a South American population, ranging from Ecuador to Chile. Worldwide, other regional populations are Northeast Atlantic, including the Mediterranean Sea; southern Africa, from Namibia to South Africa; Southwest Atlantic, from southern Brazil to Patagonia; and the Tasman Sea, including Australia and New Zealand.

Looking back to the early 1900s, soupfins were prized for their meat and particularly liver oil, which is high in vitamin A. As a result, massive fishing operations dramatically reduced the global population, according to the International Union for Conservation of Nature (IUCN), which has placed the shark on its Red List as a “critically endangered” species. Stock assessments have shown that the overall population decreased by 88 percent over the past 80 years, with ongoing declines in most regions.

From 1937 to 1949, along the West Coast, an estimated 840,000 soupfin sharks were harvested commercially, which could have caused a collapse in the population, experts say. The annual West Coast harvest dropped from 4,000 soupfins in 1939 to 287 in 1944. In 1947, scientists learned to synthesize vitamin A in the lab, which helped to reduce the demand for sharks, but even now the status of the West Coast population remains uncertain.

Responding to a petition from the Center for Biological Diversity, the National Marine Fisheries Service (also known as NOAA Fisheries) is formally considering whether to protect the soupfin under the Endangered Species Act. The deadline for the yearlong review came and went on Feb. 15 of this year with a final report not yet completed. Lisa Manning, a marine ecologist in NOAA’s Office of Protected Resources, said she expects a decision by the end of this year.

Meanwhile, soupfins remain somewhat in limbo when it comes to Washington state fishing rules, which do not mention them by name or give them special consideration. Under current regulations, soupfins are classified as “groundfish,” in which the sport limit is no more than 15 fish per day in Puget Sound. All this could change, however, if soupfins are classified as threatened or endangered by the U.S. government.

Up next: Is Puget Sound a nursery for sixgill sharks?

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About the author: Christopher Dunagan is a senior writer at the Puget Sound Institute.

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