The mysterious decline of Puget Sound herring
Rick Wood and a deck load of Norton Sound herring Credit: Credit: Eleanor Saren
Pacific herring might be the most popular dish in Puget Sound. The small silvery swimmers are called “forage fish” not because they’re rummaging for food, but because just about everything wants to eat them.
They fill the bellies of Puget Sound sea life, from giant sea lions to the iconic chinook salmon to tiny jellyfish, which means that they’re key players in the local marine ecosystem. That makes herring fundamentally important – and it makes their shrinking numbers alarming.
“They have been pushed way down and people think they are stable,” said Wayne Landis, director of the Institute of Environmental Toxicology at Western Washington University. From year-to-year, there is some fluctuation in the approximately 20 herring stocks that spawn in Puget Sound, but that misses the big picture.
“They are going on a long-term trend downward,” Landis said.
Now there’s debate over whether a proposal to build a deep-water shipping terminal at Cherry Point could nudge what was once Washington’s largest herring stock into oblivion.
Scientists are unsure what havoc the herrings’ disappearance could wreak. Some worry about the stress that fewer herring will cause chinook, which in turn are the main food for the celebrated local orcas. But there’s already evidence that the herrings’ decline can fray the local web of sea life. The first victim: An elegant black and white bird that eats the fish.
“There’s a strong connection to the Western grebe decline in the Bellingham area [and the waning Cherry Point herring]," said Joe Gaydos, chief scientist with the SeaDoc Society, a nonprofit focused on local marine health.
And what really worries those trying to save the herring is the mysterious nature of their decline. Cherry Point was once the spawning grounds for more than half of Puget Sound’s herring population. Then something strange happened.
In 1973, an estimated 15,000 tons of fish spawned on the Cherry Point eelgrass — just south of Washington’s Canadian border in the Strait of Georgia. Then the numbers began sliding, and kept sliding. The herring population dwindled more than 92 percent between the early 70s and 2012, according to population studies by the Washington Department of Fish and Wildlife (WDFW).
Herring were a popular commercial fishery dating back to the late 19th century, but state officials put the Cherry Point fish off limits temporarily in the 1980s and again in the 1990s. Today it is still off-limits, though fishing in south and central Puget Sound is still allowed.
However, even after the fishing stopped, the Cherry Point stock didn’t rebound. It made folks wonder: What is wrong with these fish?
The first of Cherry Point’s oil refineries was built in the early 1950s, followed by an aluminum smelter in 1966, and Washington’s largest oil refinery in 1971. In addition to their upland facilities, the plants have piers and release waste water into the strait.
The proximity of the beleaguered Cherry Point herring to this industrial activity has caused some people to blame industrial pollutants for their problems. After all, local herring deposit their sticky eggs on ribbony strands of eelgrass found in the sandy nearshore, and the deadly effect of petroleum pollutants on herring eggs is well documented, from Prince William Sound to San Francisco Bay.
The Cherry Point fish are notorious for their particularly sickly offspring, which have smaller amounts of yolk, lower hatching weights, shorter bodies, and a greater percentage of skeletal deformities compared to local stocks. In adult fish, a range of toxic chemicals can weaken their immune system and make them more vulnerable to disease, alter their metabolism and jumble key hormones.
So is pollution the smoking gun?
Marine toxics gurus at WDFW and the Northwest Fisheries Science Center measured pollutants in herring caught in Puget Sound and the Strait of Georgia, including Cherry Point. The Puget Sound herring were deemed to be “significantly contaminated with PCBs, and to a lesser degree DDTs…” according to research published in 2008. The Strait of Georgia fish were polluted too, but at noticeably lower levels.
A 2005 study by federal, state and university scientists tried to unravel the cause of the terrible mutations found in the newly hatched Cherry Point herring. The researchers incubated Cherry Point eggs in water from elsewhere in the Sound, and took eggs from other stocks and raised them in Cherry Point water.
They found that the Cherry Point herring were abnormal no matter what they were raised in, again muddying the picture and suggesting that pollutants specific to Cherry Point were not to blame.
But what if those early doses of pollution from the refineries and smelter, plus a little-known oil spill that fouled the area’s waters around the same time, messed up the stock for good, and what we’re seeing are the lasting repercussions? Again, there’s no simple solution.
Landis is a numbers junkie. When the WWU professor took a recent crack at the Cherry Point mystery, he pulled together decades’ worth of state data on that stock and others in Puget Sound. He crunched it, combed it and concluded that not only were the Cherry Point herring becoming rarer, they were also getting younger. And they weren’t alone.
In a paper published in 2010, Landis reported that in the 70s many of the Puget Sound herring used to live 8 or 9 years. But over the decades they kept getting younger and now most live only to age 2 or 3. The younger fish have fewer, smaller, weaker offspring, reducing their survival.
Not all of the Puget Sound stocks are on life support. WDFW rates 47 percent of the region’s herring stocks as healthy or moderately healthy, while the Cherry Point stock is considered “critical” and another stock has vanished.
But in Landis’s research, he found that the collapse in life expectancy was occurring in populations from the southernmost reaches of the Sound to the northernmost. That’s important to unraveling the herring riddle.
“Whatever hypothesis you come up with,” he said, “you have to describe a Puget Sound phenomenon and not just Cherry Point.”
While Cherry Point has a relatively high concentration of industrial activity, pollution in Washington’s inland sea is widespread.
Everything from sewage treatment plants to dairies to shipyards have permits to dump their waste into the Sound. Add to that the massive slug of toxic chemicals that pour into the sea with stormwater runoff from roofs, roadways, lawns and parking lots. The state estimates that at least 8 million pounds of petroleum pollutants are slopped into Puget Sound each year along with stormwater runoff.
While the pollution alone is troubling, the toxic chemicals have accomplices.
For some of the Puget Sound stocks, more than half of the herring are infected with the parasite Ichthyophonus hoferi, which creates lesions on the heart and liver, possibly making the fish less fit and unable to out-swim predators.
Scientists also point to the disruptions caused by climate change and variability patterns (like El Nino), whose detrimental effects can include a boost in herring predators and warmer water temperatures.
And Washington’s shorelines have been transformed in recent decades. Miles of beaches are armored like castle fortresses with walls of boulders and concrete, choking the flow of upland sand to the beaches and the growth of shoreline vegetation. Docks shade and kill aquatic plants. Shadows from docks can make it harder for some fish to catch their prey, while others become more vulnerable. Shoreline development can turn lapping waves into pounding surf as the water bounces off these hard surfaces.
Add to this the lights and activity on docks and piers, trains rumbling across beachside tracks and noisy ships crisscrossing Puget Sound.
Despite the uncertainty around the herrings’ decline, champions of Cherry Point’s proposed shipping terminal are “confident that the Gateway Pacific Terminal will not have any impact on the Pacific herring population using Cherry Point,” according to a written statement provided by Joe Ritzman of SSA Marine.
Pacific International Terminals, a subsidiary of SSA Marine, wants to build a shipping hub designed to transfer up to 54 million metric tons of dry goods — mainly coal — from trains to ships. The wharf would be nearly 3,000 feet long, more than 100 feet wide and have space to dock three massive ships at once. It would be connected to land by a trestle 1,100 feet long and 50 feet wide. Three enclosed conveyors on the trestle would move the coal.
The project design would leave the shoreline bluff intact, “to preserve the natural processes in the intertidal area,” proponents say, and not require dredging. Vessels would exchange their “ballast water” – the seawater taken onboard to stabilize the ship – well offshore to reduce the risk of hitchhiking invasive species. Parts of the trestle would be built from steel deck grating to limit shading.
“The wharf has been located to minimize shading in the intertidal zone and disruption to waves, and to avoid disruption of herring spawning,” states the project’s website.
Marine scientists are leery. Charles “Si” Simenstad, a University of Washington research professor who has published numerous reports about the nearshore, says there is not sufficient data explaining how to effectively minimize shoreline harm.
“There is still very poor documentation, particularly with things like shading and loss of light and noise,” Simenstad said. Supporters of the project say it could be altered to address environmental concerns. Government agencies are working on an Environmental Impact Statement to scrutinize the effect the project could have on human health and marine ecosystems.
Additionally, Pacific International Terminals currently plans to study the Cherry Point herring in collaboration with state agencies, Ritzman said. The planned research is the result of a 1999 settlement agreement.
But the question remains: Can the terminal be built and operated in a way that doesn’t hasten the confounding disappearance of the Cherry Point herring?
“You have a declining population,” said Landis. “The most important thing for a declining population is the spawning habitat.”