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July-September 2007
Ear to the Ground
News from the Community and the Natural World
By Aleta George
At the Moss Landing Marina halfway between Santa Cruz and Monterey, I slip into a kayak and paddle toward Elkhorn Slough, one of California's largest tidal salt marshes. Just beyond the mouth of the slough, Monterey Canyon reaches seaward for 95 miles, plunging as deep as the Grand Canyon. Upwelling of cold, nutrient-rich waters here drives the food chain that sustains the birds and mammals I hope to see.
I am not disappointed. There are birds and harbor seals all around, but the stars of the show are the southern sea otters. They float on their backs with paws out and flippers flexed to retain their body heat. (Otters don't have an insulating layer of fat like seals.) Using their bellies as tables, they dine on clams and fat innkeeper worms, eating a quarter of their weight daily. They groom their faces and bodies to keep air bubbles trapped in their fur. (With up to a million hairs per square inch, sea otter fur is the thickest of any animal.)
The otter population at Elkhorn Slough has fluctuated through the years, but numbers are currently on the high side, according to the Pacific Cetacean Group (PCG), which has studied population trends here for over a decade. The average maximum of 52 otters in 1998 dropped to 27 in 2001 and continued falling for several years. In 2005, the population began to climb again, and in November 2006, PCG counted 98 otters and one pup. With a few exceptions, the otters here are non-territorial males, says Michelle Staedler, sea otter research coordinator at the Monterey Bay Aquarium.
The southern sea otter's range extends from Half Moon Bay south to Gaviota, near Santa Barbara. By the 1930s, the otter was thought extinct from over-hunting, so biologists had reason to celebrate when a small population was seen near Big Sur. Those 30 or so otters seeded the current population of around 3,000. The population is now growing by three to five percent over any three-year period, but Staedler says that isn't enough to ensure survival.
An average of 250 dead otters are found washed up on beaches every year, the victims of pollution, shark predation, starvation, toxic algae blooms, waterborne pathogens, and run-ins with fishing boats and gear. According to the Sea Otter Alliance, a group of scientists studying otter deaths, 17 percent of dead sea otters test positively for Toxoplasma gondii, a parasite found in cat waste. A bill passed in California last year requires that cat litter packages warn owners of the danger to otters when litter gets dumped in the toilet.
To learn about sea otters, go to Monterey Bay Aquarium or Sea Otter Alliance. For information about Elkhorn Slough, visit www.elkhornslough.org.
A favorite food of the southern sea otter is black abalone, a marine mollusk that has historically put down roots in rocky intertidal zones from Southern Oregon to Baja. This once-abundant creature—one of seven abalone species found off California—is nearing extinction and has moved one step closer to protection under the Endangered Species Act. The nonprofit Center for Biological Diversity (CBD), which filed the 2006 petition for listing, says the species has declined by as much as 99 percent over most of its range.
In the 1980s, black abalone off the Channel Islands suffered a massive die-off from an insidious disease known as withering syndrome, which causes severe weight loss, detachment of the animal from its rocky substrate, and eventually death. The syndrome was thought to occur only in Southern California, but the National Marine Fisheries Services reports that mortality patterns along the Central California coast suggest that withering syndrome is moving north. "Because the disease is more virulent in warm water," says CBD's Brendan Cummings, "as the sea temperatures off California and Oregon rise due to global warming, the deadly symptoms of withering syndrome are likely to spread [north]."
The National Marine Fisheries Service is scheduled to make a decision regarding listing by the end of 2007. If listed, the black abalone will be one of just four marine invertebrates protected by the Endangered Species Act.
In late spring, a thumb-size least tern chick emerges from its egg on Alameda Point. The chick's eyes are open at birth, and it can walk soon after hatching. Its parents, who shared incubation, also take turns caring for the chick. But this chick, like the others born on this abandoned runway at the shuttered Alameda Naval Air Station, has more than its parents watching out for it. It has a village. Every month (except in summer, when the terns are in residence), volunteers with Golden Gate Audubon's Friends of Alameda Wildlife Refuge help staff from the U.S. Fish & Wildlife Service (FWS) pull weeds, rake the oyster-shell ground cover, and maintain electric fences that deter predators. According to FWS, nearly the entire California least tern population is "conservation reliant." And that has been its saving grace.
Conservation measures implemented in the last 30 years have made enough of a difference for the terns that FWS's five-year review, issued last year, recommends reclassifying the species as threatened rather than endangered, since the number of tern pairs is nearly six times greater than the threshold for down-listing.
California least terns were on the first endangered species list when the act was implemented in 1970. In their breeding range from the Bay Area to Baja, scientists counted a low of 600 pairs in the 1970s, with the decline due primarily to coastal development. However, from 1995 to 2005, protection efforts helped the breeding population grow to about 7,100 pairs. Some are celebrating the population rebound, but others say that could be premature.
"We are concerned about the proposal for down-listing," says Elizabeth Murdock, Golden Gate Audubon's executive director. "There is some question whether the current reproductive rates are sustainable for the species." Although the population continues to rise, the FWS reports that the "level of fledged young per pair has declined and continues on a downward spiral."
The colony at the proposed Alameda National Wildlife Refuge is essential for the tern's eventual recovery, says Murdock. It's among the terns' most productive breeding sites, and the northernmost colony (except for two small new ones near Grizzly Island and in Pittsburg). But the status of the Alameda refuge has remained in limbo for over a decade while the Navy and FWS negotiate long-term contamination clean-up. Recently, the Veteran's Administration proposed to build on the site and Golden Gate Audubon is watching the proposal closely. They have future brooding chicks to protect. For more information or to volunteer, go to the Friends of the Alameda Wildlife Refuge.
Two grinding rocks once used by the native Patwin people at Lynch Canyon Open Space in Solano County are perfectly situated. There are strong winds for winnowing the skin from the acorns, a small creek for flushing the bitter tannins, and plenty of flat areas for drying acorns in the sun. I imagine the Patwin women singing, telling stories, and gossiping while they worked.
The grinding rocks, along with the rest of Lynch Canyon (just off Interstate 80 between Vallejo and Fairfield), were destined to be a garbage dump, "the Shangri-la of dumps," as Solano Land Trust board president Bob Berman once put it. But with the residents of nearby Cordelia taking the lead, voters rejected the dump. Now, ten years after the land trust purchased the land, the 1,039-acre ranch is open to the public.
On the day of the grand opening, I walked on the Reservoir Trail along Lynch Creek. I spooked a large bird, and hoped it was a golden eagle—a docent reported flushing one here recently. I wasn't disappointed, however, when a female barn owl whooshed directly over my head.
For hikers accustomed to acres of open space in Marin and the East Bay, it may be hard to imagine what a coup this preserve is for Solano County. Although the county is replete with oak-studded hills, picturesque rangeland, and sprawling marshes, very little of it is publicly accessible. For over 20 years, the Tri-City and County Cooperative Planning Group has been working to protect 10,000 acres of open space between Vallejo, Fairfield, and Benicia. Lynch Canyon is part of that greater vision, called the Sky Valley Cordelia Hills Open Space. The 2005 acquisition of the King-Swett Ranches marked the halfway point toward that goal.
The movement to make more land accessible to Solano County residents seems to be gaining momentum. Solano County and the Solano Land Trust have formed a partnership at Lynch to open the land to the public. Speaking at the opening ceremony, Assemblywoman Lois Wolk said, "I hope that this is a first step toward an open space and park district in Solano County." Solano is now the only county in the Bay Area that lacks one, following voter approval of a Napa district in November 2006. For Lynch Canyon directions and hours, go to www.solanolandtrust.org.
Across San Pablo Bay, Contra Costa County is also trying to manage growth wisely. The population here is expected to increase by 127,000 within 20 years, and housing for those newcomers will be built somewhere. The trouble is, developers are eyeing open space that's already home to about 150 rare species, including California red-legged frogs, western burrowing owls, San Joaquin kit foxes, and vernal pool fairy shrimp.
In 1998, the U.S. Fish & Wildlife Service and the California Department of Fish & Game encouraged Contra Costa County to develop a habitat conservation plan (HCP). According to the county's principal planner, John Kopchik, wildlife agencies worried that a project-by-project approach to development could harm those rare species. After years of work by government agencies, private developers, environmentalists, and ranchers, the East Contra Costa County Habitat Conservation Plan/Natural Community Con-servation Plan has been approved by all participating local agencies. Pending final state and federal approval and permits, the plan will be the first large-scale HCP in the Bay Area.
"The idea is to sacrifice low-priority habitats for higher-priority habitats," says Kopchik. "It's a compromise between meeting the needs of development while protecting our resources."
Under the plan, areas declared critical for conservation—such as those with vernal pools, native grasslands, oak woodland, or streams—will be purchased from willing sellers. The plan emphasizes the expansion of existing protected areas such as Mount Diablo State Park and Black Diamond Mines and Morgan Territory regional preserves. Wildlife corridors will be protected, as will the habitat of species such as the threatened Alameda whipsnake.
"An HCP allows us to look beyond protecting postage-stamp parcels to preserving landscapes," says Lech Naumovich, conservation analyst for the California Native Plant Society's East Bay chapter. The county planning department has already raised $8 million for land purchases under the HCP.
And why are developers on board? They'll be given fast-track permits for up to 11,853 acres of urban development. In exchange, they will have to purchase land for, or contribute cash to, the HCP agency. These mitigation funds will be used for the acquisition of between 23,800 to 30,300 acres of protected lands. Land acquisition will account for two-thirds of the $350 million estimated cost of the program over its 30-year term.
"Local development has regional impacts, so it makes sense to have an overarching plan," says Elizabeth Stampe of Greenbelt Alliance, a group that supported the HCP. "Now we'll see how the implementation goes." To learn more go to the East Contra Costa County Habitat Conservation Plan Association (HCPA).
California native Aleta George writes for numerous publications, including the Los Angeles Times and the San Francisco Chronicle.
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