Northwest sea lions teach humans the folly of fighting Mother Nature

by Craig Welch

THE MUSCLE-BOUND beasts sprawling across the wet wood were males, all of them, big-whiskered, furry fellows in their prime, the nourishing fat beneath their skin thick enough to measure in inches. The beasts — four California and two Steller sea lions — were lounging on two bedroom-size floating traps that, ringed with chain-link fencing, bobbed on the water like a pair of giant bird cages.

Biologists had just started using these pens to capture some of the sea lions — the ones most responsible for wolfing down imperiled salmon and steelhead below Bonneville Dam, 145 miles from the mouth of the Columbia River. The traps were simple affairs that mimicked the sea lions' simple needs. Every day, a few passing animals would launch their rippling bellies onto the platforms through open cage doors. While they lolled about in the spring air as if the platforms were any other handy haulout, authorities with binoculars compared their markings to a wanted list of known fish-gobblers. If offenders were aboard, biologists would trip the cage doors shut, trapping the predators until they could be hauled off and shipped out.

As dawn broke on Sunday May 4, the six sea lions aboard the platforms were moving freely, wriggling about like squirrely children on an unfamiliar mattress. But when Robin Brown, a marine-mammal biologist with Oregon's Department of Fish and Wildlife, got to them six hours later, the trap doors were shut and the squirming had ceased. All six sea lions were dead.

Authorities immediately suspected an assassin. Sea lions are known for thieving chinook from anglers' lines; perhaps a vigilante fisherman had taken revenge. Certainly the circumstantial evidence was convincing. Two sea lions had metal fragments in their necks. A metal slug was lodged in the blubber of a third. Rangers the day before had found three elephant-seal carcasses in California, each with gunshot wounds to the head. Federal authorities quickly announced what they presumed had happened: Someone had shot and killed these creatures. Another endangered-species conflict had been settled with a gun.

To those who grasp the West's cultural DNA, it seemed an obvious end to another chapter in the story of man vs. nature. We build dams and locks and re-engineer rivers to suit our needs, each time generating unexpected problems. In trying to fix the problems, we inevitably generate new ones. Resolutions remain illusive.

Truth, it turns out, isn't easy to pin down. In the case of the sea lions, the facts that emerged created more questions than answers: The bodies yielded no bullets. The slug and bits of metal biologists found had been stuck in the animals for years. The actual cause of death did little to clear things up: Something had agitated these sea lions. They died gnawing at each other. Stress made their blood vessels ooze like soaker hoses, filling their lungs and livers with fluids. Their tissue and internal organs actually started cooking, the burn so intense the heat still radiated hours later. On a chill, sunless morning, these animals had boiled to death.

"There's just no telling what got them so worked up," says Peregrine Wolff, an Oregon Fish and Wildlife veterinarian who helped perform autopsies on them. "In other cases where we've trapped sea lions, they're laid back, even though they're out of the water way longer. This is truly a mystery, one we'll probably never solve."

In the Pacific Northwest we've gone head to head with these fin-footed tricksters for decades. Yet even in death, sea lions can outsmart us.

SEA LIONS — the ones called California sea lions in particular — are sophisticated creatures that can learn and adapt, a sort of water varmint that humans find both amusing and frustrating. Pat Gearin, a sea-lion expert with National Oceanic and Atmospheric Administration Fisheries in Seattle, keeps a few photographs of some of their greatest hits: a sea lion that wiggled itself onto the back of a police car; one staring at a sign as if questioning the words; a dozen sea lions napping on the back of a Navy submarine. But when things get more serious and we war with these mammals, it's almost always about fish. Gearin has seen sea lions cruise net lines and bypass low-grade pink salmon and chum for the tastier sockeye that humans prize, too. Brown, with the state of Oregon, says sea lions have been known to track boatloads of weekend-warrior anglers. "When the fishermen jump up with their pole and go 'Hey, I got one, I got one,' the sea lion will see that and come over and try to find the fish on that hook."

As far back as the 1870s, business leaders complained to The New York Times that sea lions were driving fish from San Francisco Bay. A century later in Seattle, government agents went after steelhead-snarfing sea lions at the Ballard Locks, trying to harass, scare and ultimately truck them away.

The latest front in this battle is the eighth-of-a-mile stretch of the Columbia below Bonneville Dam. Foraging sea lions travel in roving gangs, scarfing almost anything, from herring and squid to perch, pollock, flatfish, hake and lamprey eels. Of the quarter-million California and 31,000 Steller sea lions roaming the West Coast, nearly 2,000 spend the majority of their time wolfing at the buffet line of the Columbia River estuary.

As the sea lions have moved upriver to the dam, the Californias have been slurping up threatened steelhead and salmon while the Stellers dined on 30-year-old sturgeon, the breeding-age fish that keep those dinosaurs of the deep thriving. And every day each spring, squadrons of men and women have taken up arms to hold off the assault.

These daily missions, organized with militaristic precision, often come off like aquatic Wile E. Coyote episodes. Dawn to dusk, scouts with binoculars and hand-held radios squat on walkways at the dam, eyeing slack water just downstream of its fish ladders. They are hunting for the flutter of gathering seagulls, a sign that something huge is ripping apart fishy flesh. If they're lucky, they may even see a sea lion's snout.

When these observers spy predators around the fish, they can call in air strikes, radioing marksmen from Wildlife Services, the U.S. Department of Agriculture's animal-control specialists. From an arsenal more suited to a child's toy box, these expert gunmen choose weapons intended to make sea lions turn and flee: firecrackers and noisemakers shot from starter pistols; projectile beanbags and rubber bullets fired from shotguns; acoustic bombs that create underwater "noise barriers."

With people-shy Stellers it often works. California sea lions, though, aren't much for cooperation.

The Californias hoist themselves onto flat concrete sections of the dam to stare down on passing fish. They chase salmon so far up the fish ladders that their furry bodies fill public-display windows, threatening to turn tourists' salmon-viewing into a dismemberment scene worthy of the Nature Channel. (The Army Corps of Engineers recently put up jail-style crossbars to keep the mammals from the fishway.) Even dropped "pingers" — highly engineered underwater sound bombs honed to a frequency designed to aggravate sea lions — have proved ineffective. The animals just swim by with their heads above water.

Often the dam unit has been forced to call for help from a marine platoon. Armed tribal crews or state and federal wildlife technicians cruise in boats, working the river like Wildlife Services hunters work the dam's face.

But the animals are quick; their powerful fins capable of sending them plunging hundreds of feet in minutes, far more than necessary to escape a few pop guns. They can swim 100 miles in a day and hold their breath for 15 minutes. When the water is choppy, the boatmen are lucky to even see the animal through the spray.

"Some animals just won't leave the vicinity of the dam," says Brad Cady, a Washington Department of Fish and Wildlife sturgeon researcher who hazed sea lions along this stretch from December 2007 to this past May. "They'll swim under the boat, swim around the boat, swim back toward the dam; they just won't leave."

ON A DRIZZLY day this past spring, Robin Brown, who oversees Oregon's role in this adventure, stood on an island in the river below the dam to showcase his predicament.

Two small California sea lions, one with its scraggly-whiskered chin on the other's back, lazed below on a concrete slab. Four snouts popped up together and hovered off a pebbly beach. A pale Steller sea lion floated by like a lost raft, its tiny head out of place on its cedar-trunk-thick body. Bullet noses and glassy coal eyes pierced the surface like periscopes, only to be quickly withdrawn.

In this small corridor Brown spied 15 or more sea lions. "They're all over the place," he said, turning his ear to the cacophony floating up from the water. While Stellers grunt and bellow like grizzlies, California sea lions issue throaty barks, a sound like muted bursts from a fluegelhorn. Brown has worked so long around sea lions that when a loud bickering pair interrupted him, he cupped both hands to his mouth and loudly barked right back. Just as abruptly he returned to what he was saying. "See, there're four or five of them swimming around right here. There's a branded one over there. And farther up around the corner there's some lying on this wall."

Before 2001, it was rare for sea lions to come this far. No one is entirely sure what changed, but biologists presume many factors played a role. Before the Civil War, sea lions were machine-gunned from ships for sport or for their hides and oil, their whiskers sold abroad to be used as pipe cleaners. Their numbers declined with commercial hunting until the middle of the 20th century. After Congress passed the Marine Mammal Protection Act in 1972, a rebound turned to an explosion. By the 1990s, hungry sea lions were chasing smelt into the Lower Columbia. As the smelt runs tapered off each March, a few more of the burly mammals ventured farther upstream in search of fish.

Then in March 2001 a tempting smorgasbord arrived: the river's single-largest run of spring chinook since the completion of the dam in 1938. Smelt to a California sea lion is as common as hamburger, but chinook are the equivalent of prime Kobe beef, and suddenly they were zipping by like snack platters at a cocktail party. "The sea lions just flooded upriver on fishing excursions," Brown says. "Ultimately, a few of them figured out salmon fishing was pretty good."

Fish tend to slow or hesitate before maneuvering past obstacles such as dams. Ever-inventive, sea lions positioned themselves to snare fish with minimal effort. "Intelligence is a term that people developed to measure humans," Brown says. "What I say about sea lions is they are extremely good learners. And they're very, very adaptable." Each year more came back until as many as 150 now tuck in to meals of two to six fish a day. "I have seen an animal take eight or 10 fish, just one after the other, in a period of four or five hours," Brown says. "But that may mean he'll haul out for a day and a half and not eat anything else."

The amount of fish consumed increased each year. In 2001 sea lions ate a half-percent of all returning adult fish at Bonneville. By 2007 the sea lions ate more than 4 percent — about 3,900 fish. And those counts include only what observers witnessed from their perches, not fish that were taken from elsewhere downriver. Monitors also estimated that one-third of the fish passing through the dams had scars from near-misses with sea lions.

In deciding what to do, Brown and his colleagues looked backward. There they found mistakes to avoid.

WHO COULD forget Herschel and Hondo? Longtime Northwesterners may recall we have been here before, at the Hiram M. Chittenden Locks in Ballard, just north of downtown Seattle. In the late 1970s, fishermen began noticing sea lions at the Locks. At first the phenomenon was merely curious. By the 1980s, the curiosity was a crisis.

Steelhead returning to Lake Washington numbered 3,000 fish a year. A few sea lions could eat hundreds in a season. Forbidden by law from moving or hurting the animals, government biologists tried nearly everything else — much of it in front of crowds and cameras. The biologists fired metal pellets from slingshots, shot rubber-tipped arrows from crossbows and tossed the sea lions fish pumped full of lithium chloride, a sort of ipecac intended to nauseate them. The feds dropped firecrackers that exploded under water, piped in killer-whale sounds to make the predators feel like prey, and even tried to scare the animals with a plastic orca. The sea lions moved and then came right back. "What they realized was, it didn't hurt, and they were missing out on a good thing. They decided it was worth the risk," said Joe Scordino, a retired marine biologist with NOAA Fisheries.

For awhile, the biologists simply chased the animals around, but the sea lions learned to avoid the men in the boats and orange survival suits. "You could watch them, and as soon as they saw anyone wearing orange they would move away," Scordino said. "They were clearly learning." Pretty soon the sea lions even set up territories like basketball players working a zone. When workers put in a barrier net, a sea lion quickly breached it. Suddenly the animal was trapped with all the fish between the net and the Locks.

Finally after getting permission to trap and move a few animals, fisheries agents captured some of the sea lions and dumped them off the Washington coast. The sea lions returned to the Locks less than two weeks later. "It seemed like they were back quicker than the trucks that took them there," Scordino said.

The next year the animals were set free off the Channel Islands in California. They were back at the Locks for steelhead season that winter. In the mid-1990s, biologists even moved the 800-pound Hondo to an empty fish-rearing bin at a steelhead hatchery.

After getting permission, biologists finally hauled the worst offenders to Sea World in Florida. The problem was resolved. Of course by then the annual steelhead run had dipped to 70 fish, making the Locks a significantly less attractive spot for lunch.

"No one," Scordino said, "ever thought it would be as bad as it was."

WHEN WE DEAL with nature, few things go as planned.

The advice from Scordino and other biologists for the Columbia was simple: Remove the problem animals before they bring their friends. But the Marine Mammal Protection Act required biologists to detail which animals caused the problems. That took years of collecting data.

Last spring the federal government agreed Oregon and Washington could remove 85 animals a year, though biologists suspected they only needed to move about 30. Those with a track record of killing salmon would be targeted. Only if no zoo could take them would the states kill the sea lions. Reactions were decidedly mixed. The Humane Society of the United States sued, arguing that the sea lions weren't a problem: fishermen caught three times more salmon than the sea lions ate. Fishermen supported the plan, but called it a diversion. "Dams take many, many, many more fish than sea lions," said Glenn Spain, with the Pacific Coast Federation of Fishermen. "Dams are the elephant dancing on the table."

Beginning in late April, biologists trapped seven sea lions. One died during a health exam and the others were flown to Sea World. Then on May 4, the two Stellers and four Californias showed up dead in Brown's traps, leaving all the scientists scratching their heads.

Brown remains convinced that humans influenced the deaths. Something — or someone — had to shut the doors on both traps at once, an unlikely coincidence.

Others viewed the deaths as a reminder of how much we don't know. It's really only been about 20 years since the government starting capturing sea lions at the Locks, says Gearin of NOAA. "Before that there were no real techniques for handling these wild animals." Of the 1,600 animals biologists have trapped and tagged in Puget Sound, only one, Gearin says, has died in the process.

Still, Peregrine Wolff, the veterinarian, says the possible explanations seem endless. The animals could have fought one another, or been aroused by sea lion play outside the traps. The animals also could have suffered "capture myopathy," a poorly understood phenomenon in which animals die from the stress of being caught. "When we capture wildlife or chase them by truck or helicopter, there's a certain threshold beyond which they just can't take the stress," she says.

Either way, trapping — but not hazing — has been suspended until March 1, 2009. By then a federal appeals court is expected to have ruled on the Humane Society of the United States' appeal. The states are expected to have installed new lights and remote-operated cameras around the traps.

By then, another season of sea-lion wars will be in full swing.

Craig Welch is a Seattle Times reporter on leave until February.