Can Man Replace Nature? Environmentalists Say No

Out along the backwaters of the Santa Margarita River near Fallbrook, a chain-link fence surrounds a four-acre parcel covered with weeds and wildflowers swaying in the breeze.

It may not look like much, but this plot and a smaller parcel a mile upstream may represent a brave new world of environmental technology.

Sprouting amid the weeds are hundreds of tiny, hand-planted sprigs of willows and sycamores, oaks and cottonwoods. Little more than sticks with a few paltry leaves, these saplings are part of a dogged attempt by local water officials to prove that they can replicate Mother Nature by nurturing the sort of riparian vegetation that thrives along the Santa Margarita.

The success of the project is critical if the Fallbrook Public Utility District is to win approval of a controversial plan to build a 200-foot-tall concrete dam on the Santa Margarita, a $45-million project that comes more than six decades after residents first began talking about taming the scenic waterway.

Perhaps the chief obstacle to the dam is the least Bell’s vireo, a tiny, gray songbird that is on the federal endangered species list. The bird, which currently numbers only about 300 pairs nationwide, makes its home in the thick canopy of willows and underbrush that line wild rivers such as the Santa Margarita.

Growing a Habitat

That is where those yearling trees behind the chain-link fence come in. If water officials are to get a green light to erect the dam and inundate a stretch of the river considered part of the bird’s territory, they will first need to grow habitat elsewhere along the river that proves alluring to the least Bell’s vireo.

At best, the test plots represent a difficult venture. While any backyard gardener can grow a willow or sycamore, federal officials say mankind has never successfully replicated the natural mosaic of vegetation that provides a habitat for the vireo, which nests in low-lying bushes beneath a shield of taller river-bank trees.

But if successful, the experiment could prove a boon for more than 50 other public works projects in the planning stages throughout Southern California that, like the Fallbrook dam, have been stalled because of their potential impact on the fragile vireo population.

Despite all the fanfare, environmentalists are dubious at best. They consider the Fallbrook project highly experimental and suggest that efforts to reproduce vireo habitat will take upwards of a decade, an estimate that makes Fallbrook water officials wince.

“Their main goal is to build a dam, not to help save the vireo,” said Evelyn Ashton, president of Friends of the Santa Margarita River. “Their goals are counterproductive to preservation of the vireo in the upper watershed of the river.”

Known for its spectacular song, the least Bell’s vireo is a migratory bird that at one time roamed from Northern California to Mexico. Its numbers dwindled, however, as its stream-side habitat has been destroyed and brown-headed cowbirds, which displace eggs in vireos’ nests, have invaded its territory.

Even if vireo habitat can be re-created, Ashton and other environmentalists contend that the dam should not be built since it would dramatically alter the natural characteristics of the Santa Margarita, one of the last free-running rivers in Southern California.

“This is the only river in this area that hasn’t been degraded beyond recognition,” Ashton said. “I think we need to save something for our future generations.”

Moreover, Ashton maintains that the dam simply is not needed. She said water officials should look to tap some of the rich water deposits in the massive underground aquifer that lies beneath Rancho California, northeast of Fallbrook in Riverside County.

If built, the dam also would prove a problem for the utility district’s customers, Ashton argued. Characteristically, flows on the Santa Margarita are very low, meaning it could take decades for a reservoir to fill up if there were no torrential rainstorms, Ashton said.

Imported Water

“It seems kind of obvious that Rancho California would be a good alternative,” Ashton said. “And we think the river would have a better use in its natural state. We’ve done this sort of thing to our environment for too many years. We’re at the point now where we have to be very careful.”

Fallbrook Public Utility District officials say they are trying to show such care by exploring how to best re-create the vireo’s nesting grounds. Moreover, district officials contend that a dam is vitally needed to free residents from the reliance on water imported from outside Southern California.

Gordon Tinker, general manager of the utility district, said he understands the hopes of Ashton and other environmentalists, but disagrees on the facts. He said the river flows sufficiently to keep a 50,000-acre-foot reservoir filled in all but the driest of years, noting that the Santa Margarita roared with more than 200,000 acre-feet of water during the wet winter of 1980.

While the Rancho California aquifer does represent a vast source of water, Tinker said water officials there do not yet know the yield of the underground pool. Until they do, he said, “for their board of directors to give some away would be for them to ask to be recalled” by voters.

With few other choices, Tinker said Fallbrook water authorities must press forward with plans for the dam. And to get it built, they must first tackle the question of how to re-create new habitat for the least Bell’s vireo.

Tinker said the test plots, which were planned and established with $40,000 in district funds, are intended primarily to identify and refine the techniques that will be used in the future to create a new home for the vireo. The project was supervised by Portland, Ore.-based Beak Consultants Inc.

Mortality Rates

As the vegetation, which was planted in the first week of April, begins to take root, officials will be able to determine the mortality rates of plants and put a dollar value on future mitigation efforts, Tinker said. To help the trees grow during the first year, the district installed a sprinkler system at both test plots and erected the chain-link fence to keep out dirt bikers.

Ranging from seedlings in one-gallon containers to some relatively mature trees transplanted from 15-gallon pots, the plants will be studied until the spring of 1989. By then, district officials hope to have enough evidence to prove to federal wildlife authorities that the vireo habitat can be re-created, although many biologists contend such proof will take far longer.

“We want to show not only some good faith, but that there are some techniques available,” Tinker said. “We don’t want to have to agree to some lengthy wait while we see if the critters have moved in.”

As currently envisioned, the water district likely would begin trying to re-create vireo habitat upstream from the dam and along a creek that runs through the nearby Camp Pendleton Marine Corps base, which shares water yielded by the Santa Margarita.

On the upstream portion, a series of 10-foot-high rock check dams are being considered as a way to silt up the river, creating a broad flood plane in which willows and other trees could be grown.

Such an approach would produce a more expansive habitat for the vireo than the narrow strip of brush on river banks that currently exists along the portion of the river slated to be under water. Tinker said the larger area would, if anything, prove more inviting to the vireo because the bird prefers a buffer zone between its nesting area and civilization.

“You get into these narrow corridors of riparian and you don’t find the vireo,” Tinker said. “It would appear that the kind of habitat we’re talking about will be better than what we have along the river now.”

While federal wildlife officials commend the Fallbrook Utility District for undertaking the experimental plots, they note that the task of replicating habitat for the bird will likely prove tedious. In particular, regulatory agencies will take a close look at the Fallbrook dam proposal since the Santa Margarita plays host to the largest single least Bell’s vireo population in the country.

Rulea Are Tougher

“It was a wise move for the utility district to begin looking at these test plots,” said Nancy Kaufman, U.S. Fish and Wildlife Service Southern California region supervisor. “Certainly the service is going to be conservative in its analysis of a project that stands to have a large negative impact on an endangered species.”

Since the bird is federally listed as endangered, rules affecting public works projects proposed in its territory are far tougher than traditional mitigation measures, Kaufman said. Generally, proof is required that an endangered species has occupied the replacement habitat before a construction project can proceed.

“The endangered species act won’t be stopping projects,” Kaufman said. “It may involve alternatives and may take time to indeed prove that habitat can be created. But the alternative would be extinction for the endangered species.”

While Kaufman and many other experts say no man-made riparian habitat has yet proved hospitable for the least Bell’s vireo, some biologists contend it is only a matter of time.

John Rieger, California Department of Transportation San Diego district biologist, said a 6-acre tract his office has nurtured for five years along the San Diego River upstream from Interstate 15 has the just the right mix of vegetation for the vireo, although no birds nest in the area currently.

Federal wildlife officials have “not taken the time to study our site in the context of the least Bell’s vireo,” Rieger said, adding that he is eager to have vireos released in the area to see if a satellite population would form, proving the man-made habitat is acceptable to the birds.

Such an event would provide a significant push for the proposed Fallbrook dam and other public works projects impacted by the vireo. Water district officials in Fallbrook realize that resolution of questions about the bird’s habitat will go a long way toward getting work started on a dam.

“We’ve tried to prove to the project opponents we’re serious about objections they raise,” said the utility district’s Tinker. “They keep saying we don’t really give a damn about the environment and, well, it’s not really true.”

But environmentalists such as Ashton remain unimpressed. They simply want to see the Santa Margarita remain unspoiled.

“If we’re going to have solid, wall-to-wall civilization from Santa Barbara to Mexico, our green spaces will be a lot more valuable,” Ashton said. “Future generations will appreciate those who have had the foresight to preserve something that can’t be replaced.”