A  living  laboratory:
Picture
December 27, 2000
Willamette River assessed in dozens of studies, from temperature to population growth
By LANCE ROBERTSON
©The Register-Guard - Used with permission

GARY YEAGER IS knee-deep in a fish-holding pen just below Dexter Dam southeast of Eugene, leading the annual capture of salmon that must be hauled upstream to the Oakridge hatchery he manages for the state Department of Fish & Wildlife.

Yeager reaches into the holding pen, grabbing large chinook as fast as he can. Knocked out by harmless carbon dioxide gas, each fish is pushed across a stainless steel table to waiting volunteers who hoist the salmon into a tanker truck.

Yeager suddenly stops, leans his head down and uses his teeth to grab a small electronic tag implanted near a salmon's dorsal fin. He pulls it out and hands it to a woman who records the number on the tag on a clipboard.

Over the summer, Yeager and his crew move more than 9,000 chinook around the dam, which has no fish ladder. But none of those fish are as important as those that have the tags.

The tags were implanted two months earlier at Willamette Falls, about 200 miles downstream, as part of a landmark study of how many wild salmon - now protected by the federal Endangered Species Act - survive being caught by fishermen and released back into the wild.

"This has never been done before in Oregon," says Bob Lindsay, the Oregon State University professor and state fish biologist who heads the study.

Lindsay isn't the only researcher who's doing ground-breaking work on the Willamette River. From Waldo Lake to the contaminated Portland harbor, scientists and researchers are examining the river as never before.

Declining salmon runs are the focus of much of the work, but concerns over pesticides in the water, the loss of streamside vegetation, warmer-than-normal water temperatures and the impact of the Willamette Valley's rapid population growth are the subject of dozens of ongoing studies.

The Willamette is becoming a living laboratory, much like the region's old growth forests were in the 1970s. Researchers are studying everything from why so many deformed fish are showing up in the river to what impact another 1.9 million people over the next 50 years will have on the entire valley.

"Some of the work that we're doing now on the river will be the most important research ever done," says Andy Reasoner, another state fish biologist. "It's cutting edge."

Gee-whiz research

Scientists studying the Willamette employ some of the most advanced gadgetry available, such as sophisticated satellite-positioning systems for creating maps and ultra-sensitive infrared cameras - mounted on helicopters - to pinpoint slight variations in the temperature of the river and its tributaries.

The research isn't just academic. Fish biologists, river ecologists and other scientists say the work they're doing will help the governor, state and federal agencies and the Legislature make important decisions during the coming year about how to protect and restore the river, either through cooperative efforts or by government regulation.

Lindsay's fish-mortality study is a prime example.

Biologists have always wondered how many fish survive after anglers catch and release them. Fishermen must throw back wild salmon and steelhead because they are protected under the Endangered Species Act. They can keep hatchery-raised fish, which are marked by a clipped fin.

But how many of the released fish live? And if too many die, some biologists wonder, should we further limit or end sport fishing in the river?

Each spring for the past two years, biologists have anchored just below Willamette Falls at Oregon City.

There, they catch up to 150 fish, tag them, and then let them swim up the fish ladder at the falls.

They try to track the fish, largely by using tags turned in by fishermen who catch them later upriver, or by scouring streams for tagged salmon that died after spawning. Many make it all the way to Dexter Dam.

"We want our study to be a realistic representation of actual fishing," says Lindsay, the OSU professor in charge of the study.

Reading the river

On a cool spring day, another study is under way on the Willamette. A fish wheel spinning in the river near Harrisburg methodically captures young salmon as they head downstream to the ocean.

State biologists catch the fish there and on the nearby McKenzie River - the Willamette's sole remaining healthy spawning ground for wild chinook salmon - then implant electrical tags about the size of two grains of rice.

Later, scientists recapture the fish at Willamette Falls, more than 150 miles downstream near Portland, where they pass a hand-held bar-code scanner over each fish to get a readout telling them when and where it was tagged.

Because so much of the river's original side channels and other habitat have been destroyed, scientists want to know if fish are now using the main stem to feed and rest in, or if they just high-tail it downstream once they leave the tributary where they were born.

The juvenile fish study may prove to be a crucial missing link in understanding the Willamette River and the life cycles of its endangered salmon.

The results also will give scientists and decision-makers a clearer picture of which sections of the river they should target for restoration to help keep the salmon - which have declined in numbers to around 3,000 wild fish from about 300,000 a century ago - from going extinct.

"We're trying to get a feel for how fast these fish are moving down the system," says Reasoner, a state fish biologist working on the two-year project. "We're trying to get a handle on which parts of the river they're using."

Attracting the best

Stan Gregory has come out of the hills and onto the flatlands. As one of the nation's premier river ecologists, he has spent most of his career in the woods, studying how old growth forests and streams interact.

One of his long-term studies tracks how wood moves around in streams and affects habitat for fish, salamanders and other river wildlife.

But much of his time these days is spent on the main stem of the Willamette, often near his home and office in Corvallis, where he's a professor at OSU.

Gregory has embarked on a study to figure out how much natural river is left. Human development since 1850 has turned a complex series of "braided" stream channels between Eugene and Portland into a hemmed-in river with a single course, diminishing the amount of slower side channels where fish like to feed.

Gregory's research - which involves using aerial or satellite images as well as plain old hoofing it along the river - so far indicates that almost two-thirds of the river's natural flow and more than 85 percent of its historical riverside vegetation have been destroyed.

He's also taking the research a step further: He's trying to identify areas most in need of restoration that also may be the easiest, economically, to restore.

For example, restoring a section of river in downtown Portland has economic costs that are so high it's not worth it to try, he says. But a portion that runs through farmland has a low economic cost for restoration, making it a prime candidate.

"We're not trying to turn the river back to what it was like in 1850," Gregory says. "We're just saying there's potential to restore some of it."



Willamette `a high priority'

Doug Cushman throttles back the twin 65-horsepower engines and idles his 16-foot boat near the Hawthorne Bridge in downtown Portland. A depth-finder tells him how much line to let out as a 100-pound weight takes a Teflon-coated container to 2 feet above the bottom of the Willamette.

It takes only a minute for the container to fill. A hydraulic winch brings it back up.

In the back of the boat, crewman Clyde Doyle carefully puts the sample in a glass carboy and labels it. He wears surgical gloves so he doesn't contaminate the sample.

Cushman and Doyle are part of a U.S. Geological Survey team that samples the river several times each week during the summer. The water goes to the federal agency's lab, where it is tested for toxic chemicals, pesticides, heavy metals and sediment.

"The Willamette is a high priority for us," Cushman says.

Probably no government agency has studied the river as intensely in recent years as the U.S. Geological Survey, an Interior Department agency that has been gathering data for the past decade on two dozen of the nation's largest rivers.

Since 1991, the USGS has combed the Willamette Valley from Goshen to the Columbia River, looking for pollution, erosion and other problems.

And it found a lot: 50 pesticides in the water; herbicides and toxic chemicals in the groundwater; mercury and heavy metals in the river; and dioxin - a byproduct of the paper bleaching process - in the water, fish and riverbed sediment.

But scientists still don't know exactly where the pesticides are coming from, says Dennis Wentz, the Willamette project manager for the USGS. Although pesticide levels were higher in streams that run through agricultural land, no one can say for sure which fields the chemicals ran off of during a rainstorm.

The data is proving useful, however, to decision-makers and government agencies in charge of enforcing environmental laws. For example, biologists working for the National Marine Fisheries Service, the agency in charge of protecting salmon, are using the pesticide data to determine whether even low levels of chemicals in the water are affecting the species' reproductive cycle.

Early, inconclusive results indicate that pesticides may disrupt thesalmon's natural homing instinct, which tells the fish where to spawn.

The state Department of Environmental Quality and state agriculture officials can use the information to help them write water-quality plans that will be the basis for bringing 1,550 miles of streams and rivers in the Willamette Valley back to good health.

Chauncey Anderson, a USGS scientist who has done many of the federal agency's studies, says a lot of the pollution, such as DDT and dioxin in riverbed sediment, probably has been there a long time, even before former Gov. Tom McCall led the last Willamette River cleanup in the late 1960s. Many tests then weren't sophisticated enough to find a lot of the pollutants that are showing up now, he says.

Paul Risser, the OSU president who has led several task forces studying the Willamette, says the information being gathered by scientists and researchers is essential if we are to clean up the river and address the environmental problems posed by a rapidly growing population.

"Data collection and reporting will drive state and federal actions," Risser says.

"It may be the most powerful step we're taking."

Print