Will the salmon be back in 2009?

Climate change may help explain the historic collapse of the species. Yet ocean experts see signs that idle fishermen can fire up their boats again.

Topics: Environment, Global Warming, Science

As winter chills the rivers and streams of California and Oregon, a beleaguered batch of chinook salmon has finally finished its long trip home from the Pacific Ocean. In the gravel of gentle rapids and shaded pools, eggs laid by a decimated group of females are growing, starting the next generation of chinook on their turbulent journey to the ocean and back.

For their part, Pacific fishermen can only hope for the best. After all, it would be tough for things to get worse. In 2008, both commercial and sport fishing for the salmon was completely shut down along the coast from Southern California to northern Oregon for the first time in history.

“This was the first time that I sat around San Francisco and wasn’t out there catching wild California king salmon,” says Larry Collins, one of roughly 1,500 commercial fishermen forced to spend summer on dry land.

Collins and his fellow anglers blame debased rivers for the collapse of one of the country’s prime salmon fisheries. An onslaught of dams and diversions that channel water to suburbs and subsidized crops has depleted fresh water for the fish. The Central Valley river system has historically produced one of the largest runs of chinook in the continental United States. Yet in 2008 roughly 90 percent fewer salmon returned to spawn than in 2004.

“The cities, farms and all the other users have over-drafted the river,” says Collins. “Every time you take another acre-foot out of the delta, you put another nail in the coffin of the commercial fishermen of California.”

For decades, fishermen and environmentalists have directed their ire at the degradation of rivers. But in the last year, marine biologists have focused on increasingly stressed oceans as the cause of the crash. Yet surprisingly, as 2009 dawns, salmon experts see signs that idle fishermen can start firing up their boats again in the coming year.

Bruce MacFarlane of the National Oceanic and Atmospheric Association (NOAA) Salmon Ecology Team in Santa Cruz explains that the historic 2008 crash begins with the fact “that ocean conditions weren’t good when the salmon went to sea.” Salmon need the right food in the right places to thrive to maturity in the ocean. Those needs weren’t met for 2008′s salmon run, whether the cause is global warming, as many scientists suggest, or simply the natural variability of the environment. And, of course, the rivers are still a major player. If the salmon population wasn’t already in a weakened state, there would have been more survivors left to spawn the next generation.



“A natural period of poor ocean conditions hurts the salmon more than it did historically,” says Peter Moyle, a fisheries biologist at the University of California Davis. “Under normal circumstances, you would have so many fish coming out that they could more or less overwhelm the poor ocean conditions.”

Yet the common thread in the failure of the salmon seems to be the sea. Coho and chinook salmon from up and down the coast — not just from one river or river system — all declined. “When you start looking at what they have in common, it is that they share the same ocean at the same time,” says MacFarlane.

The unfavorable conditions weren’t in 2008 and 2007 when adult salmon failed to return from the sea — but three years earlier, when the fish were only a few months old and the ocean’s food chain fell apart.

“Salmon went to sea expecting the usual bountiful harvest, and they found a desert instead,” says Bill Peterson, a NOAA fisheries biologist based at Oregon State University’s Hatfield Marine Science Center who has been studying the local oceans for 30 years. “I think they were dead within a couple of weeks.”

A signal of distress came in 2005, says Bill Sydeman, chief scientist with the Farallon Institute. The Cassin’s auklet, a seabird that feeds on the same prey that young salmon do, failed to produce a single chick on the ecologically vibrant Farallon Islands. Located nearly 30 miles off the coast of San Francisco, these rocky islands are a well-studied seabird sanctuary. Around the same time, fisherman also noticed the lack of krill — a favorite food source for juvenile chinook, and an important part of the oceanic food chain.

“There were a couple of years when we saw hardly any krill at all,” says veteran California fisherman Chuck Wise. “When there’s a lot around you’ll see big clouds of it on the surface. The water will almost be red and it will come up on your trolling wires.”

The ocean is vastly changeable — having ups and downs is par for the course. So what exactly went so terribly wrong in the last few years?

The Pacific Fishery Management Council, one of eight regional councils of federal and state officials whose task is to oversee conservation and management of marine fisheries in the country, developed a list of 64 different factors, such as wind direction and water temperature, that could have contributed to the collapse.

While marine biologists say the salmon crash can’t be blamed on any single factor — “That’s not how it works in ecology,” says Sydeman — the key problems stem from oceanic processes called “upwelling” and “retention.” Upwelling refers to the process in which winds from the north push water away from the coast every spring and summer. The warmer surface water is then replaced by cold water that comes up from the depths and carries abundant nutrients such as nitrates, phosphates and silicates.

These nutrients feed the plankton, which then bloom into massive populations. Because the process happens on a relatively regular schedule, many animals — such as salmon and Cassin’s auklets — have evolved to depend on these massive, seasonal influxes of food.

Juvenile fall-run chinook salmon migrate into the open ocean from the relative stability of their home streams and estuaries between April and June. They almost always find abundant food waiting for them, given that upwelling begins in March and April, and lasts all summer. But in 2005 and 2006, the ocean broke the rules. In 2006, upwelling started early — in February — and then it stopped, occurring only sporadically throughout the summer. In 2005, the upwelling simply didn’t start until mid-summer.

As a consequence, auklets and other marine life that depend on the same food as salmon simply starved to death. Scientists think the same thing happened to the chinook, says Brian Wells, a NOAA scientist based out of the Southwest Fisheries Science Center in Santa Cruz.

In addition to the sparse and ill-timed upwelling, intense winds pushed what little food there was far offshore, according to Wells, who has spent the past few years studying ocean conditions in the California Central Coast region. He modeled the production rates of krill, seabirds and rockfish for up to 30 years and correlated them with staggering quantities of data on environmental conditions, looking for a relationship with how the salmon population relates to changes in the ecosystem from year to year. He found that in 2005 and 2006, remarkably low amounts of food were retained near the shore.

“Just because food is out there doesn’t mean it’s accessible,” Sydeman says. “Predators such as salmon seem to do best when the krill are in very large patches, even if there are fewer patches. And they have to be in the right place.”

Some scientists — such as Peterson — also suggest that the vagaries of the Pacific Decadal Oscillation (PDO) correlate with the hardships confronted by the salmon. The PDO describes sea surface temperatures for a vast swath of the Pacific Ocean, north of Mexico. As a result of winds, the ocean will sometimes be warm near the coast and cold in the middle, and then flip-flop so water near the coast is cold instead. “When the ocean is in cold phase, salmon do really well, and when it’s in warm phase, salmon do horribly,” says Peterson. But in the last decade, he added, the PDO has “gotten all goofy.”

Based on more than 100 years of data, scientists say each PDO phase generally lasts for 20 or 30 years. Now, instead of multi-decadal cycles, the flip-flopping has been happening every few years. A 20-year warm phase ended in 1999, followed by three years of cold phase. From 2003 to 2006, during the time when the salmon were suffering, it was warm again. Since then, it has returned to a cold phase. Whether these changes indicate a temporary variation or a long-term trend won’t be known for years, says MacFarlane.

The warmer sea surface temperatures that are inherently an aspect of poor upwelling are also a problem for salmon. The fish need much more food to survive in warm waters, whether or not they are associated with the PDO, MacFarlane adds. Some say this is due to plankton, the tiny plants and animals that myriad sea creatures — including salmon, squid, seabirds and whales — rely on for food. Some eat the plant plankton directly; some eat the animal plankton, such as krill, that feed on the plant plankton; others eat the small fish that feed on the krill, and so on.

However, not all plankton are created equal. “The species in Alaska are like bears,” Peterson says. “They’re quite big and they pile on the fat so they can hibernate through the winter.” When local coastal waters are chilly, Alaska-type plankton thrive off the west coast of Oregon. Some researchers hypothesize that ocean currents carry both cold water and fatty plankton down from Alaska and this is what feeds the salmon.

When the ocean is warm, the plankton are skinny and so are the fish, Peterson says. Lean plankton frequently found in the tropics take the place of the fatty, northern variety. “They’re not going to be as strong, not as feisty and they won’t grow as much,” says Peterson. “For best salmon conditions, you have to have the right kind of water, with the right kind of plankton — and you also have to have some upwelling.”

Many scientists suggest that climate change is part of the problem. For over a decade, research has predicted that global warming could lead to upwelling that was strong, but occurring late — as well as less food retention along the coast. “They actually suggested we would see a trend like we have been seeing in the last few years,” says Wells.

“I’m confident that climate change is leading to changes in the environment, and starting to affect lots of food webs in a lot of different ways,” says Sydeman. He adds that 2002 saw the highest levels of both salmon and Cassin’s auklet reproduction on record, while the lowest rate for both came just a few years later in 2005. “Things are getting more and more variable, which is one of the predictions of global warming — that the systems are going to get less predictable,” he says.

Yet other scientists say there is not yet any clear evidence that upwelling, retention or the PDO are being affected by climate change. “We don’t have a long enough time series to see if there’s a relationship between oceanographic conditions and greenhouse gases,” explains MacFarlane. Predictive models disagree widely about how specific places in the ocean are going to fare in the future, he adds.

Whatever their cause, the ocean conditions triggering the 2008 crash have eased up — at least for now. Fortunately for fish and fishermen alike, conditions improved in 2007, and 2008 yielded abundant upwelling, cold waters and vibrant life in the sea. Krill were abundant; whales and porpoises fat and feeding; and seabird colonies thrived.

“The ocean looks in better condition now than I’ve seen in 25 years, except for the salmon,” Collins says. “There’s more rock cod, more marine mammal predators, and the sardines are back. The ocean is full of life.”

It looks like this is going to be “a great year to be a baby salmon,” says MacFarlane. “I hope that turns out to be true; we really need good ocean conditions and low predation to start rebuilding that stock.”

Still, say the scientists, the future of the salmon, and the seas, remains precarious. Oceans worldwide face the long-term problems of acidification, pollution and hypoxia. Freshwater rivers are increasingly stressed. And regions of the ocean that are still generally healthy, such as those off the California and Oregon coast, have proved how vulnerable they are to short-term variability.

“It’s kind of a cheat out to say that it’s all better, because I’m not sure that it is,” says Wells. “Just because 2008 was OK doesn’t mean that 2009 will be.”

Jacoba Charles is a freelance writer based in Point Reyes, California.

More Related Stories

Featured Slide Shows

  • Share on Twitter
  • Share on Facebook
  • 1 of 11
  • Close
  • Fullscreen
  • Thumbnails

    Ten spectacular graphic novels from 2014

    Beautiful Darkness by Fabien Vehlmann & Kerascoët
    Kerascoët's lovely, delicate pen-and-watercolor art -- all intricate botanicals, big eyes and flowing hair -- gives this fairy story a deceptively pretty finish. You find out quickly, however, that these are the heartless and heedless fairies of folk legend, not the sentimental sprites beloved by the Victorians and Disney fans. A host of tiny hominid creatures must learn to survive in the forest after fleeing their former home -- a little girl who lies dead in the woods. The main character, Aurora, tries to organize the group into a community, but most of her cohort is too capricious, lazy and selfish to participate for long. There's no real moral to this story, which is refreshing in itself, beyond the perpetual lessons that life is hard and you have to be careful whom you trust. Never has ugly truth been given a prettier face.

    Ten spectacular graphic novels from 2014

    Climate Changed: A Personal Journey Through the Science by Philippe Squarzoni
    Squarzoni is a French cartoonist who makes nonfiction graphic novels about contemporary issues and politics. While finishing up a book about France under Jacques Chirac, he realized that when it came to environmental policy, he didn't know what he was talking about. "Climate Changed" is the result of his efforts to understand what has been happening to the planet, a striking combination of memoir and data that ruminates on a notoriously elusive, difficult and even imponderable subject. Panels of talking heads dispensing information (or Squarzoni discussing the issues with his partner) are juxtaposed with detailed and meticulous yet lyrical scenes from the author's childhood, the countryside where he takes a holiday and a visit to New York. He uses his own unreachable past as a way to grasp the imminent transformation of the Earth. The result is both enlightening and unexpectedly moving.

    Ten spectacular graphic novels from 2014

    Here by Richard McGuire
    A six-page version of this innovative work by a regular contributor to the New Yorker first appeared in RAW magazine 25 years ago. Each two-page spread depicts a single place, sometimes occupied by a corner of a room, over the course of 4 billion years. The oldest image is a blur of pink and purple gases; others depict hazmat-suited explorers from 300 years in the future. Inset images show the changing decor and inhabitants of the house throughout its existence: family photos, quarrels, kids in Halloween costumes, a woman reading a book, a cat walking across the floor. The cumulative effect is serene and ravishing, an intimation of the immensity of time and the wonder embodied in the humblest things.

    Ten spectacular graphic novels from 2014

    Kill My Mother by Jules Feiffer
    The legendary Pulitzer Prize-winning cartoonist delivers his debut graphic novel at 85, a deliriously over-the-top blend of classic movie noir and melodrama that roams from chiaroscuro Bay City to Hollywood to a USO gig in the Pacific theater of World War II. There's a burnt-out drunk of a private eye, but the story is soon commandeered by a multigenerational collection of ferocious women, including a mysterious chanteuse who never speaks, a radio comedy writer who makes a childhood friend the butt of a hit series and a ruthless dame intent on making her whiny coward of a husband into a star. There are disguises, musical numbers and plenty of gunfights, but the drawing is the main attraction. Nobody convey's bodies in motion more thrillingly than Feiffer, whether they're dancing, running or duking it out. The kid has promise.

    Ten spectacular graphic novels from 2014

    The Motherless Oven by Rob Davis
    This is a weird one, but in the nervy surreal way that word-playful novels like "A Clockwork Orange" or "Ulysses" are weird. The main character, a teenage schoolboy named Scarper Lee, lives in a world where it rains knives and people make their own parents, contraptions that can be anything from a tiny figurine stashable in a pocket to biomorphic boiler-like entities that seem to have escaped from Dr. Seuss' nightmares. Their homes are crammed with gadgets they call gods and instead of TV they watch a hulu-hoop-size wheel of repeating images that changes with the day of the week. They also know their own "death day," and Scarper's is coming up fast. Maybe that's why he runs off with the new girl at school, a real troublemaker, and the obscurely dysfunctional Castro, whose mother is a cageful of talking parakeets. A solid towline of teenage angst holds this manically inventive vision together, and proves that some graphic novels can rival the text-only kind at their own game.

    Ten spectacular graphic novels from 2014

    NOBROW 9: It's Oh So Quiet
    For each issue, the anthology magazine put out by this adventurous U.K.-based publisher of independent graphic design, illustration and comics gives 45 artists a four-color palette and a theme. In the ninth issue, the theme is silence, and the results are magnificent and full of surprises. The comics, each told in images only, range from atmospheric to trippy to jokey to melancholy to epic to creepy. But the two-page illustrations are even more powerful, even if it's not always easy to see how they pertain to the overall concept of silence. Well, except perhaps for the fact that so many of them left me utterly dumbstruck with visual delight.

    Ten spectacular graphic novels from 2014

    Over Easy by Mimi Pond
    When Pond was a broke art student in the 1970s, she took a job at a neighborhood breakfast spot in Oakland, a place with good food, splendid coffee and an endlessly entertaining crew of short-order cooks, waitresses, dishwashers and regular customers. This graphic memoir, influenced by the work of Pond's friend, Alison Bechdel, captures the funky ethos of the time, when hippies, punks and disco aficionados mingled in a Bay Area at the height of its eccentricity. The staff of the Imperial Cafe were forever swapping wisecracks and hopping in and out of each other's beds, which makes them more or less like every restaurant team in history. There's an intoxicating esprit de corps to a well-run everyday joint like the Imperial Cafe, and never has the delight in being part of it been more winningly portrayed.

    Ten spectacular graphic novels from 2014

    The Shadow Hero by Gene Luen Yang and Sonny Liew
    You don't have to be a superhero fan to be utterly charmed by Yang and Liew's revival of a little-known character created in the 1940s by the cartoonist Chu Hing. This version of the Green Turtle, however, is rich in characterization, comedy and luscious period detail from the Chinatown of "San Incendio" (a ringer for San Francisco). Hank, son of a mild-mannered grocer, would like to follow in his father's footsteps, but his restless mother (the book's best character and drawn with masterful nuance by Liew) has other ideas after her thrilling encounter with a superhero. Yang's story effortlessly folds pathos into humor without stooping to either slapstick or cheap "darkness." This is that rare tribute that far surpasses the thing it celebrates.

    Ten spectacular graphic novels from 2014

    Shoplifter by Michael Cho
    Corinna Park, former English major, works, unhappily, in a Toronto advertising agency. When the dissatisfaction of the past five years begins to oppress her, she lets off steam by pilfering magazines from a local convenience store. Cho's moody character study is as much about city life as it is about Corinna. He depicts her falling asleep in front of the TV in her condo, brooding on the subway, roaming the crowded streets after a budding romance goes awry. Like a great short story, this is a simple tale of a young woman figuring out how to get her life back, but if feels as if it contains so much of contemporary existence -- its comforts, its loneliness, its self-deceptions -- suspended in wintery amber.

    Ten spectacular graphic novels from 2014

    Through the Woods by Emily Carroll
    This collection of archetypal horror, fairy and ghost stories, all about young girls, comes lushly decked in Carroll's inky black, snowy white and blood-scarlet art. A young bride hears her predecessor's bones singing from under the floorboards, two friends make the mistake of pretending to summon the spirits of the dead, a family of orphaned siblings disappears one by one into the winter nights. Carroll's color-saturated images can be jagged, ornate and gruesome, but she also knows how to chill with absence, shadows and a single staring eye. Literary readers who cherish the work of Kelly Link or the late Angela Carter's collection, "The Bloody Chamber," will adore the violent beauty on these pages.

  • Recent Slide Shows

Comments

0 Comments

Comment Preview

Your name will appear as username ( settings | log out )

You may use these HTML tags and attributes: <a href=""> <b> <em> <strong> <i> <blockquote>