Where the wild things are
First-of-its-kind report could provide a blueprint for saving state’s critters
Researchers from the Wildlife Health Center usually do hands-on work in the wild, like affixing radio collars to cheetahs and testing game birds for avian flu. But over the last two years, some of the UC Davis researchers have been studying the work of wildlife conservationists instead. The goal, according to project manager David Bunn, was to learn how to protect and preserve habitat for California’s threatened species. The end result is the state’s first-ever comprehensive report on all California species living in habitats shrinking yearly due to tremendous growth and development.
“This is the one-stop-shopping document for conservationists,” said Bunn.
In October, California submitted its wildlife action report to the U.S. Fish and Wildlife Service, as did every other state in the nation, as part of State Wildlife Grants, a federal program that provides California with $3 million a year for habitat preservation.
Supplemented by a comprehensive wild-animal matrix, the report has gone way beyond previous studies that focused on species preserved for fishing and hunting. While identifying all species of concern in California, the report also describes the multitude of stressors that threaten them and recommends a host of creative, sometimes radical, solutions for preserving what remains of California’s disappearing habitat.
Though SN&R obtained an early copy of the report, titled “California Wildlife: Conservation Challenges,” it will not be released officially until early 2006.
The UC Davis team, in association with the state Department of Fish and Game, divided California into nine regions. Each region is profiled with detailed maps that show conservationists which species live in which habitats.
For instance, the chapter on the Central Valley and the Bay-Delta region explains that there are “490 vertebrate species that inhabit the Central Valley and Bay-Delta Region … including 279 birds, 88 mammals, 40 reptiles, 18 amphibians, and 65 fish.” Over a quarter of the birds and reptiles, almost half the mammals, and a third of the amphibians and fish are considered species of concern by the Department of Fish and Game. Some of them, including the riparian brush rabbit, are only found in the Central Valley.
To explain the variety of stressors, the Central Valley chapter profiles three distinct species, including two that already are receiving attention from government and private conservationists. Researchers found that the spring-run chinook salmon only flourish when water-resource managers cooperate to remove barriers; the Swainson’s hawk prefers to breed on private lands like farms around Sacramento, Davis and Stockton, meaning that farmers are responsible for its habitat; and the Tulare grasshopper mouse, a little-understood animal, can survive only on undisturbed lands, meaning that one of its major threats is the constant development of open space.
In fact, the major stressor for all of California, “far and away,” said Bunn, “is growth and development.”
“In the Central Valley, 99.9 percent of the historic native grasslands, 99 percent of valley oak savanna, about 95 percent of wetlands, 89 percent of riparian woodland, 66 percent of vernal pools, and 67 percent of San Joaquin Valley shrublands are gone,” the report states.
But Bunn’s group also offers hope that by partnering with owners of both public and private land, California can reverse some of the damage caused by continuous population growth.
According to senior conservation biologist Marc Hoshovsky with the state Department of Fish and Game, there are multiple creative solutions already in practice in California. The trick is expanding their use.
One success story began more than 30 years ago on a farm in Winters.
Private farmers and ranchers own about half of California’s habitat, making them some of the state’s most promising conservation partners. John Anderson, owner of Hedgerow Farms, already cooperates with the Yolo County Resource Conservation District and grows native grass seed on lands once devoted to row crops like tomatoes and corn.
California has lost a lot of biodiversity, said Anderson. “We have great potential to put it back in on the edges.”
In 1979, said Anderson, his was the first local farm to intentionally add hedgerows—bushes and trees that form a hedge—around the boundaries of his farmland to provide habitat for game birds. He found that by increasing the size of the usual edges and easements around his crops, and growing native grasses and wildflowers on lands that are usually “sprayed naked” with pesticides, even private farms become habitat for game birds.
“One percent would not be farmed anyway,” he said. By increasing the easements to 2 percent, Anderson learned that pheasant and quail returned, as did beneficial insects, which make up for the small loss of income by cutting down on the need for pesticides.
Looking out his window at the migratory birds, Anderson said that in recent years he’s seen pheasants, doves, turkeys and a once-elusive California quail.
“We see snakes now,” said Anderson. “Deer also came back. … The insect populations are spectacular.”
By planting native trees and shrubs along canal banks, Anderson even helps improve the quality of the water. About 20 percent of the water in canals escapes through groundwater, said Anderson, which is drawn up by the deep roots of native trees and shrubs and cleansed by beneficial microorganisms.
Bunn sees this as evidence that it’s possible to increase habitat by making simple changes in public and private lands. Even recreation areas can become invaluable habitat if they’re well-designed, he said.
To mitigate further habitat loss, the team recommends setting back levees to give rivers room to meander and overflow their channels; building regional plans so that cooperation occurs between bioregions; and preparing for climate change, which could drastically add to the salience of California water.
Once water levels rise, and saltwater starts flowing into the Delta, said Bunn, we could lose the opportunity to make habitat preservation a priority.
Now that the report has been submitted, Bunn said he was surprised at the commonality between California regions, which vary from desert to forest. The team found that water-management issues and invasive species threaten wildlife statewide.
According to Hoshovsky of Fish and Game, the Central Valley used to be covered in native grasses, but with settlement by the Spanish, those grasses were overgrazed by horses and cattle, and invasive Mediterranean grasses were able to take over. Even today, he said, ships in the San Francisco Bay release ballast water that includes invertebrates from other ports. According to his research, a new species is introduced to the port every 14 weeks. “They’re able to survive and spread throughout,” he said.
The $3 million California receives annually in State Wildlife Grants is less than originally planned by Congress and too little to help California reverse the trend toward invasive species and ever-decreasing habitat. Bunn said that the federal government asked for wildlife action plans to ensure that if states receive more money, they’ll know how to use it.
Researchers already are dreaming about what California could do with more funds for preservation. Bunn said his first interest is preserving and improving riparian habitats like the canals on Anderson’s farm.
Hoshovsky wants to provide more support for programs already working in California.