This year’s herring spawn events in Puget Sound were the largest in decades

Puget Sound Partnership
Puget Sound Partnership
10 min readMay 14, 2020
A whitewater Pacific herring spawning event in Agate Pass, by Brainbridge Island. Photo credit: Brian Whitlock.

Throughout the Sound in March and April, Pacific herring were spawning in large numbers. In Quilcene Bay and Dabob Bay, in Port Orchard and Port Madison, in Henderson Bay, and near West Seattle, and possibly in Discovery Bay, Holmes Harbor, and elsewhere. There’s uncertainty about the precise extent and the size of the spawning due to stay-at-home restrictions limiting observation and measurement, but it’s clear that this has been a big year for herring. Pacific herring and other forage fish play an important role in the food web of the Salish Sea, and their spawning biomass is tracked as one of the Puget Sound Vital Signs.

“Our Sound-wide total for 2019 was just under eight thousand metric tonnes,” said Adam Lindquist, a biologist at the Washington State Department of Fish and Wildlife (WDFW). “If you take what happened at Quilcene and the Port Orchard-Port Madison stock, this year is going to beat the total that we had for all of Puget Sound last year.” Lindquist said that the total spawning herring biomass estimate this year is the highest WDFW has documented since 1983, and if you include the agency’s best guess at what has been missed due to the lockdown, it would probably be the highest since 1980. He added that, although the numbers are impressive, there are a few caveats to keep in mind: WDFW is now surveying more areas than they were in the 1980s, and most herring stocks have been surveyed every year since 1996, with the exception of the three newly discovered stocks — Wollochet Bay in 2000, Purdy in 2008, and Elliott Bay in 2012.

In early March, community members like Kirie Pedersen — who lives on Dabob Bay, near Brinnon — started noticing increased feeding activity from sea mammals and birds. Pedersen said she saw sea lions, harbor seals, bald eagles, and shore birds all feeding by the water near her house. A few days later, the activity was even more pronounced. “During this period, hundreds of birds appeared along with more eagles, harbor seals, sea lions, and even transient orca, no doubt to feast on the seals, all this feeding activity accompanied by twenty-four-hour-a-day vocalization,” she said.

Pedersen, who had received an email from the Coastal Watershed Institute (CWI) a few days before asking that locals keep an eye out for herring spawning activity, notified the institute and Dr. Anne Shaffer, CWI’s executive director and lead scientist. Shaffer and David Parks, a longtime CWI collaborator, documented the spawning event from Whitney Point south to Wawa Point.

Photo of Pacific herring eggs in Hood Canal. Photo credit: Anne Shaffer and the Coastal Watershed Institute.
Photo of Pacific herring eggs in Hood Canal. Photo credit: Anne Shaffer and the Coastal Watershed Institute.

Shaffer and Parks recorded the spawning event through aerial and underwater photos and videos over the course of multiple days. “There does seem to be an increase in the spawn intensity and also in the geographic extent, or where they’re spawning, throughout the Salish Sea,” Shaffer said.

Around the same time, Jon Oleyar, marine fish biologist with the Suquamish Tribe, started hearing about extraordinary numbers of sea lions and seals in Port Madison Bay. “Although we do have some seals and some sea lions out there, the activity was just off the charts,” said Oleyar. “And then I started getting reports of huge schools of silver fish going right by the dock in downtown Suquamish and all over.”

Photo of Pacific herring eggs coating eelgrass near Port Madison. Photo credit: Tom Ostrom
Photo of Pacific herring eggs coating eelgrass near Port Madison. Photo credit: Tom Ostrom, ecosystem recovery manager with the Suquamish Tribe.

Steve Todd, salmon recovery biologist with the Suquamish Tribe, reported hearing about similar activity. “When we get these big herring spawn events, you get a lot of other animals following them around for food. So the whole food web is in action and it’s kind of a big spectacle.”

Oleyar said he almost did a double take when a fisherman called him up to say that he’d gone out and caught a thousand pounds of herring. “I’ve been with the Suquamish Tribe for about 25 years or so, and that’s the very first time I’ve ever had a fisherman go out and catch herring,” Oleyar said. “That was a big deal.” Most of the Suquamish tribal elders Oleyar spoke to about the herring spawn said they hadn’t seen anything like it in 50 or 60 years, and he reported that the younger members of the tribe had only heard about the herring fishery from their parents or grandparents. Oleyar provided some anecdotal information on the Port Orchard-Port Madison herring stock: “When I first started with the Suquamish tribe back in the late nineties, I used to accompany the Fish and Wildlife folks to do herring surveys. And back then there actually weren’t many eelgrass beds around the reservation. So as you can imagine, our findings were on the low side or none at all, just traces of herring spawn because there really weren’t any.”

Bainbridge Island has been the center of much of the herring spawn activity. As Todd and Oleyar explained, the March spawning event was centered on the north and northeast parts of the island. Brian Whitlock, who lives on Bainbridge near Agate Pass, could tell something was happening in the water near his home because of all the sea lion and eagle activity. But he wasn’t sure what he was seeing until he heard from others about the herring. “Turns out I was seeing the white water [spawning] event from my backyard,” he said. “I’d encourage others to notice the observable above-water changes in sea lion and eagle behavior as a key indicator of an event below the surface of the water.”

Photo of bald eagle preying on spawning Pacific herring in Agate Pass. Photo credit: Brian Whitlock.
Photo of bald eagle preying on spawning Pacific herring in Agate Pass. Photo credit: Brian Whitlock.

Later, at the beginning of April, herring were spawning along the east side of Bainbridge Island as well. Dylan Tomine, Bainbridge Island resident and author, spoke about what he saw. “It was a spectacular event, lasting several days and through many tides,” he said. “Seagulls, terns, eagles, sea lions, porpoises all gathering for the feast. At the end, there was — and still is — piles of herring eggs on the eelgrass and mounds of unattached eggs nearly a foot deep on parts of the beach. A truly uplifting experience at a time when we could all use some good news. I’ve been living on and fishing the Sound for years, and I’ve never seen this much visible life happening.” The event that Tomine witnessed stretched from Point Monroe to the south end of Fay Bainbridge Park, he said. Todd mentioned that he’d heard the spawning continued south down to Murden Cove too.

In mid-April, CWI received word from Martha Kongsgaard, former chair of the Puget Sound Partnership Leadership Council, about a spawn event by West Seattle, near Me-Kwa-Mooks Park. Laura James, diver and photographer, took drone photos of the event and documented it on video as well.

Photo of whitewater herring spawning event near West Seattle. Photo credit: Laura James, Beneath the Looking Glass, LLC.
Photo of whitewater herring spawning event near West Seattle. Photo credit: Laura James, Beneath the Looking Glass, LLC.

In addition to those areas, Lindquist mentioned that the herring spawning in Henderson Bay — what’s referred to as the Purdy Stock — had seen an increase this year as well. “We discovered that one in 2008 and it’s been trending downward the last few years,” he said. “We had just over 100 tonnes last year, and it’s been under 100 tonnes in the previous five years, but this year’s total will be at least 800 tonnes. So once again, that’s good to see, especially since that stock is in Southern Puget Sound and we’ve been concerned about stocks down there trending downward the last five or 10 years.”

Why is this year different?

No one can say for sure why this year’s herring spawning might be different, since there’s no way to get good data right now. Both Shaffer and Todd mentioned that ocean conditions may have played a part in the health of the herring and the increase in spawning activity, but there are a number of other hypotheses too.

“My intuition is, it’s probably a combination of factors,” Shaffer said. “And I also have a pretty strong feeling that the combined effort of an entire generation of restoration work is helping as well.”

Oleyar echoed Shaffer’s opinion. “The tribe has been really involved, along with private landowners, and Fish and Wildlife, trying to bolster a lot of the eelgrass beds in Puget Sound,” he said. “I think when you do something remarkable to the habitat, or put habitat in place where it wasn’t before, sometimes those organisms really respond to that.”

Photo of hatching herring larvae near Wawa Point in Hood Canal. Photo credit: Dave Parks and Coastal Watershed Institute.
Photo of hatching herring larvae near Wawa Point in Hood Canal. Photo credit: Dave Parks and Coastal Watershed Institute.

Lindquist says that, under normal circumstances, WDFW would be able to do more research to try to determine why the herring spawn activity this year has increased — they would take samples to check how old the fish are, to see whether something happened three or four years ago that contributed to this year’s abundance; perform genetic analysis on the fish to see if there are any clues about where they came from; and maybe analyze their contaminant load to determine where the fish have been. Lindquist said there’s also a possibility that predator distraction has led to the increase in the spawning herring population. “Since the Blob [the warm water ocean event of 2013–15], we’ve seen an increased number of anchovy in the Sound, which to some people might be seen as a competitor, but they could also be distracting predators from herring when they’re spawning,” he said. “So maybe we got a good strong class a couple years ago when the predators were distracted, and now we’re reaping the benefits a few years later when those fish come back to spawn. There could also be something to those anchovy spawning and providing more zooplankton in the water column for the herring to eat.”

Oleyar also offered a philosophical take on why this has been such a big year for herring. “Every once in a while when something bounces back and we can’t put a substantive reason on why, or why now, it kind of makes me smile a little bit. Because, you know, we don’t have all the answers. But sometimes nature can heal herself, and we can’t take all the credit — or any credit.”

Herring and the food web

Pacific herring are an important prey species for Chinook salmon and other fish, birds, and mammals, and they play an important role in the Puget Sound ecosystem food web. As Shaffer explained, “The entire food web of the Salish sea is closely linked to herring spawning. The annual herring spawning is a dramatic event, when large groups of adult herring shoal off the shore, then come to the shore in mass. The female herring lay eggs heavily on the vegetation, and the males fertilize the eggs with clouds of milt, generating white water plumes that settle within hours. Each spawning event sets up a ‘herring cascade’ that feeds our entire coastal system. After hatching, larval herring fill the Salish Sea with zooplankton that feed the system. Baby herring migrating off their nursery grounds are prevalent in the nearshore exactly when the juvenile salmon are coming out of their watersheds. And it’s a critical nexus for our salmon. If those forage fish weren’t there, and herring in particular weren’t there, we’d see a great loss in our salmon community.”

Both Todd and Oleyar spoke about how the herring population can affect salmon, and, in turn, orcas. Todd said, “I think it’s generally really encouraging to see this and herring is a key forage fish species, and not just for the salmon, but as you can watch from shoreline, they’re important for a lot of different creatures in Puget Sound, all the way up. Potentially, if they are affecting salmon, that may cascade up to the Southern resident orca. It’s great to see this, and whether this is an outlier and we don’t really see this kind of thing for many years or decades again is another question. Or is this a harbinger for more consistently abundant herring spawn events in the future?”

Oleyar said that he thinks it’s important for folks to take notice of what’s happening in the natural world — like the herring spawning — and focus their attention so they can better appreciate everything that surrounds us. “Don’t take it for granted. Help in any way we can. Like, say, plant eelgrass or take out a bulkhead on the beach. So I encourage everybody to take a second or two, stop and look around, and notice what’s there. A lot of times, things are right in front of our eyes and we’re so busy trying to get from here to there that we don’t even notice.”

Learn more through the Puget Sound Vital Signs

Graphic of a colored wheel depicting the different components of the Puget Sound Vital Signs.

The Puget Sound Vital Signs are measures of ecosystem health and progress toward Puget Sound recovery goals. Thanks to a strong network of monitoring programs and committed scientists and environmental program managers in the Puget Sound Ecosystem Monitoring Program, the status and trends of indicators and progress toward recovery goals are regularly updated throughout the Puget Sound Info website.

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