Sacramento River Spill Killed Aquatic Ecosystem : Environment: ‘This habitat is gone,’ a state biologist laments. Disaster looms for nearby wildlife.

Like a kick in the gut, the scope of the loss finally hit Mike Rode last Tuesday. The sparkling Sacramento River--his longtime laboratory, his workplace, his back yard--was dead, killed by a wily chemical demon that escaped from a wrecked train car.

Rode went diving that day--pulled on a wet suit, snorkel and mask and plunged into a deep river pool with some fellow fish experts. After days of anxious speculation, the biologists wanted to see the carnage close-up.

“It was like a cemetery down there, corpses everywhere,” Rode recalled later, describing the eerie mix of decaying algae and animal carcasses drifting beneath the river’s surface. “There was this huge feeling of emptiness. And it hit me that this whole aquatic ecosystem--every last living thing--was gone. It was all dead.”

There will be more death along the ravaged river, perhaps much more. The television cameras are gone, shifted on to fresher news. But left behind is a sterile stream--and a vast civilization of birds and animals robbed of their feeding trough.

The endangered bald eagle and the kingfisher, the otters and mink that burrow in the moist river banks will be getting hungry now. So too will the raccoons, the herons, the mergansers and the odd little ouzel, a gray bird that hops from rock to rock and gobbles bugs from the river floor.

There are no live fish in the waterway, no insects. And, for many river-dependent species, there are no alternatives.

“The public has the perception that these animals can just go next door and continue to survive,” David Smith, a wildlife biologist with the state Department of Fish and Game, said as he kneeled beside the foul-smelling river one recent afternoon. “It doesn’t work that way. This habitat is gone--it won’t be the same for years and years and years. . . . And there is nowhere else for them to go.”

It has been two weeks since a Southern Pacific tank car derailed and spewed its lethal cargo of pesticide into the Upper Sacramento, poisoning a 45-mile stretch from north of Dunsmuir down to Shasta Lake. As the toxic slick continues to dissipate in the reservoir, scientists summoned to the worst river disaster in California history are grimly taking stock, cataloguing the losses and mapping plans for what will be a long and difficult recovery.

The river will come back, but how quickly is anyone’s guess. The full extent of the devastation--the reach of the domino effect triggered when the poison fouled the water--is not yet clear. With no fish to eat, what will become of the osprey and their chicks peering down from treetop nests? Deprived of insects, how will the salamanders, frogs and other amphibians fare?

There are other mysteries as well. The long-term threats posed by the spilled chemical, a soil fumigant called metam-sodium, are unknown. It might disrupt the reproductive system of wildlife that ingested toxic vapors or fish contaminated by the chemical, jeopardizing future generations.

It could also ravage the river’s dense canopy of riparian plants, a vital jungle that stabilizes the stream banks and provides nesting habitat, food and shelter for many species. Already, many small willows have turned crisp and died, clumps of Indian rhubarb are brown and wilted, and towering alder and cottonwood trees are sagging, their leaves yellow.

“There are a lot of unknowns right now,” said Smith, who estimates that 250 species of birds, mammals and amphibians may be affected by the spill. What is certain “is that we’ve wiped out the entire ecological pyramid. If it had been one layer, say the top of the pyramid, it wouldn’t be so bad. But here, the whole foundation of the food chain has just been swept away.”

You can hear anguish and anger in the scientists’ voices as they walk the river, surveying the damage, making notes and theorizing about what may lie ahead. They wonder why Southern Pacific did not improve the notorious stretch of track where the train derailed. Why the pesticide wasn’t transported in a double-hulled car. Why railroad crews did not quickly pump some of the chemical out of the punctured tanker, stemming the toxic leakage.

James Nelson, a Fish and Game botanist, summed up the feeling this way: “We biologists went into this field because we like to study living things. What we’re doing here is writing an obituary.”

Mixed in with the sorrow, however, is a keen scientific curiosity: “I wish this disaster had never happened,” says Rode, who has studied the Upper Sacramento for Fish and Game for 13 years. “But scientifically speaking, we have a great, rare opportunity here to watch an entire ecosystem regenerate.”

Because of the Sacramento’s fame as an unparalleled fishing stream, public attention has focused on when the native fish will return. Hundreds of thousands of trout, sculpin and other fish were killed by the chemical plume, and some experts say it may take 10 years or more for their populations to rebuild.

But before the fishery can recover, the underpinnings of the aquatic food chain must first take root. At the very bottom is algae, the mossy green coating that makes the river’s stones slick.

The pesticide quickly killed off the nutrient-rich plant, turning it into a milky brown goo that now does little but consume oxygen as it decays. Gradually, spores of algae from tributaries and the 2-mile stretch of river above the spill will float into the sterile area and recolonize on the rocks. Assuming that there is no toxic residue in the stream, the algae may be fully re-established within a year, said Charles R. Goldman, director of the Institute of Ecology at UC Davis.

Once this fundamental food crop is thriving again, the next rung on the ladder--insect larvae--can begin to take hold. Adult insects on tributary streams will mate and lay their eggs on the river in the weeks and months to come. Their populations, however, can rebound only after the larvae’s nutritional source--the algae--is in place.

“There will be caddis flies, dragonflies, salmon flies, mayflies--all very important fish food,” Goldman said. “Some of the larvae will begin drifting into the river right away, but until the very base of the food pyramid is established, they will starve.”

Returning with the insect larvae will be tiny invertebrates like freshwater limpets and worms. Meanwhile, trout that survived in tributaries and above the derailment site will swim into the main river, looking to regain a foothold. Initially, they will find the waters an ecological desert and perish.

But ultimately--perhaps as early as next spring’s spawning season--there will be food to sustain some of them. Gradually, these pioneers will reproduce, and the fishery will expand. It will be five years or more, however, before any reach the hefty size that once drew anglers from across the state.

Once the fish return, the rehabilitation will slowly spiral upward through the pyramid, through the ranks of amphibians, small mammals and birds. Ultimately, Smith hopes, the 45-mile stretch will regain its “carrying capacity”--or its ability to sustain a diverse balance of animal life.

But no one knows when that will occur. And until it does, wildlife linked to the river are “in trouble,” Smith said. “We will lose populations. We don’t know the numbers, we don’t know how far the ripple will extend up the food chain. . . . But there will be long-term effects.”

In the hectic days since the derailment, scientists have focused on tallying the short-term losses and protecting those animals that survived. Worried that endangered bald eagles might gorge themselves on contaminated fish, crews worked feverishly to clean up carcasses that were attracting the birds.

Hoping to save osprey chicks in nests along the lifeless stretch, biologists constructed several “trout corrals” in the river, stocking them with hatchery fish. Because osprey feed only on live prey, the handout was considered essential to give the chicks a shot at reaching maturity.

Other acts of human intervention could follow. If the chemical claims large sections of greenery along the river banks, botanists might recommend replanting native vegetation--a tricky and possibly costly process.

“I can’t make any predictions yet, but in a worst-case scenario, we could lose an entire strip of vegetation--the whole canopy--and that would have many serious consequences,” Nelson said recently as he examined a shrub visibly suffering from vapors or poison taken up by its roots. “Look at this mountain mahogany. This is the hardiest plant I know--it can grow out of crevices on mountaintops. And it’s sick. It’s very sick.”

The dense layers of riparian plants not only serve as a nesting habitat for numerous birds, but provide shelter for small mammals and shade for heat-sensitive trout, Nelson said.

Moreover, loss of the vegetation would make the banks of the fast-flowing stream vulnerable to erosion, which could load the river with sediments and dramatically alter its course.

Local tourist-dependent communities are lobbying hard for the restocking of the river with fish raised in hatcheries. Without catchable fish in the prime local waterway, cities like Dunsmuir are without the main magnet drawing the vacationers who keep their economies afloat.

Restoration experts, however, strongly discourage any immediate stocking. The river’s brown and rainbow trout have their own distinct genetic makeup, they note; allowing artificially reared fish to invade and take hold could jeopardize the native population.

“It is important to do everything possible to protect the wild strain of trout in that stretch and to not introduce domestically bred hatchery fish that could contaminate the gene pool,” said John Berger, executive director of Restoring the Earth Inc., a Berkeley-based organization that promotes environmental restoration.

Rode, the biologist, agreed: “It would be easy for the interlopers to come in and compete and constitute a threat to the recovering wild population. The best practice is usually to watch carefully and leave things alone.”

Indeed, although they lament the ecological destruction and fret about the future, biologists also express great faith in nature’s capacity for rebirth.

“We’ve had some profound losses here, the food chain has been thrown out of whack, but the river will heal itself,” said Tom Hesseldenz, a Mt. Shasta biologist and regional manager of the conservation group California Trout. “The important thing is to treat the cause of this disaster, so we don’t have to go through this again.”

The Aftermath: Sacramento River Recovery

ASSESSMENT

In the two weeks since the upper Sacramento River was devastated by a toxic spill, scientists have been prowling the waterway and its banks to assess damage and inventory plant and animal life. Among the specific actions under way:

VEGETATION: Botanists are inspecting bushes, grasses and trees, looking for evidence of plant death or stress.

BIRDS: Ornithologists are checking nests to determine the fate of chicks and listening for bird calls to calculate the density of river-area species.

INSECTS: Entomologists are documenting losses and recording remaining populations that may be affected later.

WILDLIFE: Biologists are setting traps to capture mice, shrews, reptiles and other small mammals. The animals will be marked and released; their populations will be calculated and then monitored over time. Traps to help count and track larger mammals may also be used.

FISH: Experts are diving the river, surveying the extent of aquatic losses.

RECOVERY

Until the extent of damage is known, scientists are unsure how long it may take the affected 45-mile stretch of river to rebound. Here are several steps that could be taken to accelerate recovery:

REVEGETATION: If significant numbers of alders, willows, cottonwoods and Indian rhubarb die, replanting of the river banks may be undertaken to prevent erosion and provide shelter for wildlife.

ALGAE: Algae, which serve as a food source for insect larvae upon which many fish feed, will recolonize naturally as particles drift downstream from unaffected areas. But some suggest that placing algae-covered rocks in the sterile river might hasten the process.

INSECTS: Aquatic insects, critical to the survival of many fish, will gradually return as adults deposit eggs in the river. But the repopulation could be enhanced by the introduction of insects along the affected stretch.