The human eye, in contrast, can adjust to differences in light intensity, but the types and distribution of pigments in our eyes don’t change as we descend into a darkened basement or even as we age. And we don’t experience anything like the other changes that occur during smoltification. As a fish is moving from freshwater to salt water, its gills and its excretory system have to be completely remodeled. The water and the salts in a solution each move from areas where they are at high concentration to areas of low concentration. In a lake or stream, water tends to move into a fish’s body across the gills and gut wall, and salts tend to move out. To cope, freshwater fish don’t drink. They also have to rid themselves of excess water by urinating large volumes, and their gills and gut are constantly pumping salts back into the body. But in the ocean, the situation flips: water tends to move out of the body and salts tend to move in. Marine fish have to drink to avoid dehydration and then pump salts out like mad to avoid electrolyte poisoning. When a young salmon leaves its home stream to head out into the wide world of the ocean, it has to be prepared.
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When we returned to Cassandra’s redd the next morning, she was gone. There was no sign of her, save for a gleaming mound of fresh gravel. This is how you spot redds as you walk along a salmon stream: by looking for clean mounds of gravel, especially near riffles. The freshly turned stones contrast with the unexcavated rocks nearby, which have been darkened by a year or more of bacterial and algal growth. Cassandra had worked through the night and finished her magnum opus.
Peter Bahls thinks that the coho and chum females in Tarboo Creek build a single nest, but research has shown that in some species and river systems, a female may build four or five redds with five hundred to a thousand eggs in each before she is spawned out. This represents a lot of digging. In streams with big runs of 60- and 70-pound Chinook salmon, the spawning females actually rework the streambed—collectively moving hundreds of tons of gravel. It’s like a giant sandbox filled with girls playing earnestly with toy excavators.
A biologist used historical records and recent data to conclude that on average, salmon in southwest Alaskan rivers dig up at least 30 percent of the total streambed each year. As they till the substrate, small particles are swept downstream and coarser pebbles and cobbles are left behind. As a result, the fish become part of the forces determining the stream’s shape and course, along with the floodwaters that carve banks and excavate new channels, the fallen trees that deflect the current and create swirling eddies, and the logjams that dam flows and create deep pools. Salmon are movers and shakers. They are ecosystem engineers.
We never did find Cassandra’s carcass, or the remains of Fabio, Tony Bennett, Red-cheeks, or the other salmon boys. But days later, Sean Gallagher fastened a length of yellow surveyor’s tape on an alder twig near Cassandra’s redd and marked it “Coho 11/28.” Sometimes I thought of it as a grave marker; at other times as the plastic bracelet around a newborn’s wrist.
Peter Bahls and other nwi staff do spawning surveys every fall—following the fish upstream much as the bald eagles and river otters do, tying yellow or orange streamers to twigs near redds, and recording the locations on a map. When the creek was first remeandered at our place and fresh gravel was everywhere, we had thirteen of those yellow streamers on our 1,500 feet of channel. We were thrilled, but it was nothing compared to what we’ve seen on a tributary of the Hoh River, in the pristine rainforests of Washington’s Pacific coast, when the Chinook are spawning. Biologists from Olympic National Park had been marking redds for weeks with yellow surveyor’s tape before one of our visits, and the nests were so dense that the tangle of vine maple branches looked like a Christmas tree covered with tinsel. And there were still fish everywhere: females digging new redds virtually on top of old redds; males chasing each other and being chased—by two river otters. The otters were so full of fish that their bellies bulged, but they couldn’t help swimming after another Chinook every few minutes. We saw one big male salmon fight back: he rammed one of the otters in the side and chased it out of the pool where his lady love was digging.
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Now that the creek at our place is a few years older and has had a chance to remake itself, we have fewer good sites for redds. Much of the gravel is buried in silt and organic debris now; some has been piled into ridges or transported downstream by floods. The gradient through our land is relatively gentle, so the water moves slowly enough that it provides better habitat for rearing than nesting. Most of the adult coho swim through our stretch of creek now, headed for a smaller, faster, and gravel-lined stretch of stream closer to the headwaters. But come March and April, we start to see coho fry in the slower, mud-lined, and shaded portions of our creek. They’ve floated down from the redd sites and will spend their days eating and avoiding being eaten. Their time in the newly remeandered stream will fuel the growth that allows them to head to the ocean about the time we’re celebrating their first birthday.
In the summer, we can sit at the edge of the stream and watch these small fry feed. The best place for this babysitting is a rock that Bob put on a creek corner. It’s where the new watercourse leaves the old ditch—just upstream from the spot where our sandbag dam diverted the flow. This little patch of creek is ideal rearing habitat because the water slows down before it hits the earth dam that Bob made to fill the ditch. And just below the big rock where we sit, the water fans out into a broad, shallow channel that Bob scraped out using an I-beam clenched between the teeth of the excavator’s bucket.
The water in this stretch of stream is shaded by foot-wide alders that used to line the ditch and now overhang the creek. The leaves and twigs they’ve dropped into the water have created a velvety lining of rich organic debris. The big logs that Bob poked in have trapped sediments brought in by winter floods and created downstream pools; the willow stakes that our boys and Sean and I pounded in have sprouted into 15-foot-tall bouquets.
So on an August afternoon, you can perch on Bob’s rock just above the water or straddle one of the big logs he angled into the pool upstream. Either way, the creek is flowing under and around you. In the early evening, the sunlight dances through the moving alder branches and turns the creek a golden brown. If you sit still long enough, the little coho emerge one by one from the shadows under the big logs. They start fanning their tails to maintain position in the gentle current, then dart here and there to pick an insect or bit of debris from the surface. After fifteen or twenty minutes of this, you stand up and continue your walk—feeling much better, thank you.
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Chum salmon fry move into the ocean almost immediately after hatching in March or April, but the coho babies stay in the creek all summer, not migrating down to the sea until just before the next generation of parents returns in late fall. Both species spend two years in the ocean, feeding and growing, and then return to Tarboo Creek to spawn. They’re resplendent in their nuptial coloration, and they’re big. Jeff Delia, an oyster grower who does catch-and-release fly casting when the salmon are schooling in Tarboo Bay, has hooked fish that were more than 2 feet long and weighed 15 pounds.
It’s natural to wonder why salmon move from salt water to freshwater to breed. The leading explanation for this anadromous lifestyle focuses on two factors: food and predation. Freshwater is a much safer place for a salmon egg or fry than the ocean—there are many fewer midsize fish around to eat them. At Tarboo, almost nothing digs up the eggs, and the major threats to fry are kingfishers, great blue herons, and cutthroat trout. So freshwater is a good place for a juvenile fish to live during the most vulnerable period of its life. But streams, lakes, and ponds don’t offer nearly as much food as the ocean does, making salt water a better place for young fish to grow to adult size. The populations of sockeye salmon called kokanee illustrate this second point. Kokanee don’t migrate to the ocean; instead, they stay in freshwater year-round. They never attain the size of the oceangoing sockeye and can’t compete with them for the best nesting sites
. Like the jacks that appear in many salmon species, kokanee are making a trade-off between higher survival and lower reproduction.
People also want to know why salmon breed only once before dying. It’s not that the to-and-fro life makes repeated breeding impossible: sturgeon spend most of the year in salt water and breed in freshwater, but they reproduce every few years of their adult lives and can outlive a human. Salmon appear to do better as big-bang reproducers because their odds of surviving to make another long-distance trip back to their natal stream, after a return to the ocean, are low. In addition, females that throw all of their resources into one reproductive event can produce larger eggs—which give their fry an important survival advantage—and more of them. Apparently, evolution has favored individuals that put all of their effort into a single bout of reproduction over fish that hold back but then lay fewer and smaller eggs and risk dying before the next breeding season arrives.
To a biologist, salmon offer a treasure trove of questions, and just enough answers to make the research effort rewarding. But even seasoned salmon researchers never fail to thrill at the sight of a spawning run in full swing—still feeling the excitement of that little boy in an upstairs bedroom near Tarboo Creek decades ago, listening to the sound of splashing in the night.
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Peter Bahls, Sean Gallagher, and other nwi staff and volunteers have been counting salmon in Tarboo Creek since 2002. In addition to mapping and marking each redd in spawning surveys conducted during the fall, they sometimes livetrap and tally juvenile coho during the summer.
The numbers go up and down over time. I’ve worked near the creek on days when I heard a coho splash by every five or ten minutes. I’ve seen hordes of chum, near the big Sitka spruce tree at the mouth of the creek, churn the water like an outboard motor—spawning in a frenzied tangle of bodies. We’ve also had autumns when we never see a fish and can find just one or two pink streamers marking redds in the upper portion of the watershed. They dangle in the wind like two lonely people in a hall that should be filled with revelers on New Year’s Eve.
Sometimes we don’t know why the numbers are low; sometimes we do. The coho and chum that spawn in Tarboo Creek usually come into Tarboo Bay from the open ocean by late September or early October. Two large sand spits separate Tarboo Bay from Dabob Bay and the broader waters of Hood Canal. Once the salmon swim around the spits and enter Tarboo Bay, they are virtually trapped there—constricted in terms of how far they can roam. They wait in the bay, biding their time until the fall rains arrive to swell the creek and trigger the run. The situation is good for salmon watching: on a bright day you can sit by the water and watch them break the stillness with flashing jumps, or try to count their shadowy silhouettes if they swim close to the shore. But we’ve also seen harbor seals take advantage of the geography by feeding on salmon penned in the bay. And one fall an nwi volunteer saw a fishing boat pull up, anchor a net on the beach, tow the line around the schooling fish, and scoop them up in a couple of sets. The crew came back the next day and did the same thing. The following year, it happened again. For two consecutive autumns, almost no fish made it up the creek to breed.
The nwi observer who watched the beach sets claimed that the single boat took more than six hundred fish in that two-day span. A neighbor who spent twenty-five seasons fishing for sockeye salmon in Bristol Bay, Alaska, estimates that the two-day catch was worth $3,600 at the most. In the whole scheme of things, this is a tiny amount of money. It’s nothing compared to the time and effort government agencies, tribes, and private citizens have spent restoring habitat in the Tarboo watershed.
One of the salient issues in play is that Hood Canal salmon are managed as an aggregate—meaning that managers don’t care if the salmon spawning in a particular stream are wiped out as long as the total number of fish returning to the region remains fairly constant. In addition, the state runs a hatchery for coho in Quilcene Bay, just to the west of Tarboo Bay, and some of the managers insist that the fish being taken in Tarboo Bay are—all evidence to the contrary—actually hatchery-bred individuals from the Quilcene River facility and not wild fish. There are virtually no restrictions on taking hatchery-raised salmon.
Because Tarboo Creek is so small, the extinction of its chum and coho wouldn’t register in the regional totals. According to the way the regulations for managing salmon in Hood Canal are currently written, it would be perfectly legal to fish the Tarboo Creek populations to extinction.
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Fishing salmon to extirpation is a story that started centuries ago; it was chronicled by scientist David Montgomery in a 2003 book titled King of Fish. Atlantic salmon, for example, were once abundant throughout Europe. The Roman legions ate salmon caught in downtown London; an 83-pound individual was harvested from the River Thames in 1821. A quarter million salmon used to swim up the Rhine each year, with some reaching 50 pounds. French rivers once teemed with them. Now, salmon are virtually extinct from Spain to Estonia. Only Iceland’s runs are holding up reasonably well.
Unlike the situation on Tarboo Creek, the extirpation wasn’t due to lack of regulation. In 1215, the Magna Carta called for the king’s salmon weirs to be dismantled in order to preserve fish for public use. Richard the Lionheart passed a statute requiring that weirs and other trapping devices avoid spanning rivers and streams—maintaining gaps so that some salmon could reach their spawning grounds. In 1424 Scotland’s James I banned weirs and traps entirely and established a period during each run that was closed to fishing.
But throughout Europe, enforcement was nonexistent. If the fish were there, people took them. After all, no one owned them.
Overharvesting was followed by pollution during industrialization, along with major public works projects to “improve” streams: cleaning rivers of the downed wood that creates fish habitat, straightening stream channels, and building levees to prevent floodwaters from wandering around. The combination of overfishing and habitat destruction was effective. It eliminated a key source of inexpensive protein, along with one of the continent’s last traces of wildness.
As harvests began to decline in western Europe, the industry turned to Atlantic salmon populations that bred in New England, the Maritime Provinces, and Quebec. Salmon were commercially harvested from rivers that emptied into the northwestern reaches of the Atlantic Ocean, ranging from Long Island Sound in the south to Hudson Bay in the north. These fish matured in the Labrador Sea and Davis Strait off Greenland’s west coast, side by side with the populations that bred in Europe. Conservative estimates put annual runs of the North American Atlantic salmon at 5 to 12 million fish annually. The Pilgrims ate salmon frequently; Captain John Smith and Henry Hudson both noted their abundance. In 1672, an angler in Nova Scotia reported that catching 3-foot-long salmon was routine and that 6 footers were possible. Even with a 40-percent fish-story discount, those were large animals.
Historically, fishing has been conducted in what biologists call a scramble competition: if no one owns a resource, whoever gets there first and takes the most wins the competition. Sociologists refer to the result as a tragedy of the commons, based on the history of publicly owned pastures in the American colonies: farmers who overstocked benefited, even though the quality of the pasture declined and depressed the total income realized by the community. The problem was that anyone who showed restraint lost out, even though everyone would have benefited if everyone had shown restraint.
A scramble competition for the Atlantic salmon of North America’s eastern seaboard played out over a century. Predictably, it ended in a commons that looks tragic. Runs are gone from many rivers. Commercially, Atlantic salmon are extinct in most of their former range.
The story continued when Europeans arrived in the Pacific Northwest. William Clark of the Corps of Discovery saw Columbia River salmon in 1805 and wrote: “The multitude of this fish is almost inconceivable.” Recent estimates suggest that 11 to 16 million fish once bred in that river’s watershed alone. An early white set
tler of south Puget Sound named Ezra Meeker reported that during the 1870s, two men in a boat could regularly catch 1,200 pounds of salmon a night in western Washington’s Puyallup River. In the same decade, the fishing industry was cranking out 630,000 cases of canned Columbia River salmon a year, with each case containing forty-eight 1-pound tins. Often, canneries along the Columbia and in Puget Sound couldn’t keep up with the catch, and half or more of the harvest would be wasted—the carcasses dumped.
The pressure continued through the 1970s to 1990s, when fishing interests regularly took 60 to 90 percent of the annual runs. By then, the Columbia and its tributaries had been dammed in more than sixty places; the human population had exploded, and streams and estuaries throughout the region were being ruined by helter-skelter development. Salmon returns in Pacific Northwest rivers are now estimated at less than 7 percent of historical levels.
If anything, the situation is even worse in Japan, where masu, chum, and pink salmon were once abundant. An estimated 98 percent of streams throughout Japan have been dammed or otherwise altered. Most of the remaining salmon runs are on the northernmost island of Hokkaido, and many of those populations are on life support, born and bred in hatcheries. In the Pacific, only salmon native to northeast Siberia and some regions of Alaska still have healthy populations.
Saving Tarboo Creek Page 6