The Salt Pond Puzzle: Restoring South San Francisco Bay

  • A California gull comes in for a landing on the gull-filled flats of the South San Francisco Bay salt ponds

    Michael Kern and the Gardens of Eden
  • A California gull, which eats gull eggs (shown here) as well as those of other species

    Michael Kern and the Gardens of Eden
  • USGS biologists in the California gull colony at Pond A6, part of the South Bay Salt Pond Restoration Project where the gulls are encouraged to nest.

    Judy Irving © Pelican Media
  • Sources: Google Maps/South Bay Salt Pond Restoration Project
  • Caitlin Robinson-Nilsen examines a snowy plover egg at the E Ponds in the South Bay.

    Michael Kern and the Gardens of Eden
  • Snowy plovers are tiny shorebirds, whose offspring can fall prey to larger birds like California gulls.

    Michael Kern and the Gardens of Eden
  • Panorama of Salt Pond A6, taken in 2010 before the area was breached as part of the South Bay Salt Pond Restoration Project. Today, the area has accumulated sediment and looks like a natural mudflat. The image was created by stitching together 12 wide-angle frames taken by a camera at 150 feet, suspended from a kite, and is part of the Hidden Ecologies Project, http://bit.ly/NYMgAq.

    Cris Benton
  • A pair of avocets chase a California gull that had snatched their baby from a nest at Don Edwards S. F. Bay National Wildlife Refuge.

    Ken Phenicie Jr.
 

FREMONT, CALIFORNIA

We were on patrol. Caitlin Robinson-Nilsen, a young biologist in shades and a ponytail, steered the 4WD Explorer along a muddy levee in Fremont, Calif., and I rode shotgun, staying vigilant. She surveys snowy plovers –– adorable, six-inch, two-ounce, skittering shorebirds, with black collars and eye-patches –– as the waterbird program director for the San Francisco Bay Bird Observatory. But we weren't after plovers that April day last spring. We were cruising the South Bay's vast salt pond system in search of something larger, more dangerous. Through the windshield was a strange land of water and sky, rimmed with office parks. They're out there. They'll steal your lunch.

We were looking for California gulls. Trash birds, some say -- but that's only a partial description of their diet. They also adeptly hunt and devour the eggs and chicks of waterbirds like plovers -- many with a tenuous hold on disappearing habitat. Now, on the metropolis' coattails, the Bay's California gull population is going gangbusters. To make matters worse, 23,000 of them -- roughly half the Bay's population -- were displaced from their nesting grounds when the levees of A6, a 330-acre salt pond, were breached in 2010, returning it to the tides as part of the South Bay Salt Pond Restoration Project.

The gulls were on the loose, hunting for new homes, and no one, least of all Robinson-Nilsen, wanted them settling near plovers. It was one of many unintended consequences of the largest wetlands restoration on the West Coast. Break down one barrier, others are likely to crumble. Restoration is seldom as simple as banishing exotics and promoting natives; it's a series of trade-offs, and the odds are that not every species will come out ahead. Nor is it easy to delineate which species actually belong in an ecosystem as radically transformed by people and invasive species as the South Bay. Still, this restoration, like most, is optimistic: It hopes we can all be winners.

Gulls are good at winning, and well-suited to human sprawl; snowy plovers, not so much. Charadrius nivosus is an undeniably endearing bird, found all over the world. But it's a nervous soul, unsettled by tall structures. Telephone poles? As scary as hills. Their subtle nest scrapes and camouflaged eggs are found only on beaches, gravel river bars and sand and salt flats, right where humans like to build high-rises and vacation homes, walk dogs and drive ATVs, activities that can disturb or destroy nests. As if that weren't enough, snowies also have to contend with European beachgrass and climate change swallowing up shoreline nesting grounds. And now, an explosion of gulls.

Two subspecies of snowies exist in North America, the Cuban along the Gulf Coast, and the western, which consists of distinct inland and coastal populations. The latter -- Robinson-Nilsen's charge -- ranges from southern Washington to the tip of Baja, but most reside in the Bay Area and southward. In 1978, both the inland and coastal western snowies became species of special concern in California, but only the coastal birds were listed as threatened under the Endangered Species Act, in 1993.

The first statewide survey between 1977 and 1980 found snowies missing from 33 of 53 known coastal breeding locations. In the Bay Area, 351 birds were counted. By 1991, there were only 176. The low -- 72 -- came in 2003. Since then, the numbers rose to about 250. But this year, just 147 were spotted. The Bay Area is thought to host 5 to 10 percent of the entire coastal breeding population, almost all of them in the salt ponds. It's primo habitat: light-colored expanses to blend in while nesting; wet edges for hunting brine flies, using the run-stop-peck approach; and blessedly few people, since it's mostly off-limits to the public.

April to May is peak migration, and western sandpipers dotted every shallows. They were innocent. We passed them by. Up to a million migrating waterbirds stop in the San Francisco Bay on their journeys to their Northern breeding grounds, but Robinson-Nilsen spends her entire field season here, turning circles. Originally from Vermont, she discovered her passion for threatened piping plovers on Long Island. She studied snowies for her master's at San Jose State, and it became her dream job: "Anything to do with nesting plovers." She listens to the wind or to NPR, seldom bored. But as we zigzagged, she confessed, "I end up talking to the birds a lot."

When we reached the levee between A22 and A23 -- A for Alviso, a marsh-side community in northern San Jose -- there they were: A flock of roosting gulls, insouciantly ruffling their feathers, and ours, in the breeze. They're pretty snowy themselves, with a black ring and red spot on their yellow bill, and a four-foot wingspan. She counted them through her open window, jotting "110" in the California gull column of her datasheet. "Quite a bit less," she said.

But even one was too many: This was one of the bird observatory's "no gull zones." Earlier in the month, an irksome 700 had loafed here, right between two ponds with a handful of nesting plovers. "We were like, 'Oh, my goodness, we'll never be able to keep them off,' " Robinson-Nilsen remembered. The bird observatory began hazing them twice daily, and when we arrived, things seemed under control. "Once they lay eggs, they're protected by the Migratory Bird Act," said Robinson-Nilsen. "So we're putting in a big effort now."

We drove onto the levee, spattered with whitewash, chicken and rib bones, like the mouth of an ogre's cave. Robinson-Nilsen pointed south. "That big 'mountain' is Newby Island Landfill," she said. "Hundreds, if not thousands, of gulls feed there everyday." To the north was another landfill, making this levee an ideal midway hangout. We parked, stared the gulls down. It wasn't high noon, but close enough. On Robinson-Nilsen's command, we swung our doors wide and sprang out. She blew a silver pea whistle bought in Chinatown, and the sound carried like a battle cry. I wielded my notebook. The gulls flinched, scattering with a few resentful mews. Small, sweet payback, I thought, for all those pilfered hotdogs.

High Country News Classifieds
  • LAND & CABIN ON CO/ UT LINE
    18 ac w/small solar ready cabin. Off grid, no well. Great RV location. Surrounded by state wildlife area and nat'l parks.
  • MANAGER PERMACULTURE LANDSCAPE CONTRACTOR
    Permaculture / Landscape Company Manager / Site Lead Red Ant Works, Inc. - 20+ year landscape construction and horticultural care company seeks manager and site...
  • CANYONLANDS FIELD INSTITUTE
    Field seminars for adults in natural and human history of the Colorado Plateau with lodge, river trip and base camp options. Small groups, guest experts.
  • COMMUNICATIONS MANAGER
    San Juan Citizens Alliance is looking for a passionate, dynamic, organized, and technology-savvy communications professional to help grow our membership and presence in the Four...
  • ENERGY AND CLIMATE PROGRAM ASSOCIATE
    San Juan Citizens Alliance seeks an Energy and Climate Program Associate to focus on public outreach, education and organizing to advance campaigns to mitigate climate...
  • REAL ESTATE SPECIALIST
    This position provides professional real estate services and is responsible for managing and completing real estate projects utilizing a project management database that is designed...
  • WILDFIRE MITIGATION SPECIALIST
    The Wildfire Mitigation Specialist is responsible for delivering wildfire risk mitigation information, recommendations and programmatic resources to wildland urban interface homeowners, community members and partners....
  • DEVELOPMENT POSITIONS
    Thorne Nature Experience is hiring for a Development Director and Senior Individual Giving Manager. Individuals will work collaboratively with Thorne's Executive Director to develop and...
  • SENIOR PROGRAM MANAGER, LANDSCAPE CONSERVATION & ENERGY
    The National Parks Conservation Association, a 100-year-old nonprofit advocacy organization and the nation's leading voice for national parks seeks a Senior Program Manager, Landscape Conservation...
  • BACKCOUNTRY AND FRONTCOUNTRY STEWARDSHIP CREW MEMBERS
    The San Juan Mountains Association (SJMA) is hiring a crew of ambassadors to work in partnership with the U.S. Forest Service to educate visitors on...
  • EXECUTIVE DIRECTOR, NATURAL HISTORY INSTITUTE
    The Executive Director is the chief executive officer of the Natural History Institute (NHI). The Executive Director has broad authority to lead and manage the...
  • EXECUTIVE DIRECTOR AT FRIENDS OF CEDAR MESA
    - The Land, History, and People of the Bears Ears Region - The Bears Ears and Cedar Mesa region is one of the most beautiful,...
  • SENIOR DEVELOPMENT ASSOCIATE
    Greater Yellowstone Coalition seeks a Senior Development Associate to coordinate the organization's individual giving program. The position description is available at http://greateryellowstone.org/careers Please email a...
  • TRAIL CREW TECHNICAL ADVISORS
    SEEKING TALENTED TRAIL CREWLEADERS The Pacific Crest Trail Association, headquartered in Sacramento, California ,is dedicated to protecting, preserving and promoting the Pacific Crest National Scenic...
  • ENDANGERED SPECIES POLICY ADVOCATE
    Are you a Guardian for wildlife, great and small, across the West? WildEarth Guardians (Guardians) seeks a full-time Endangered Species Policy Advocate (Advocate) for the...
  • WESTERN NATIVE SEED
    Native plant seeds for the Western US. Trees, shrubs, grasses, wildflowers and regional mixes. Call or email for free price list. 719-942-3935. [email protected]om or visit...
  • THE LAND DESK: A PUBLIC LANDS NEWSLETTER
    Western lands and communities--in context--delivered to your inbox 3x/week. From award-winning journalist and HCN contributor Jonathan P. Thompson. $6/month; $60/year.
  • CONSERVATIONIST? IRRIGABLE LAND?
    Stellar seed-saving NGO is available to serious partner. Package must include financial support. Details: http://seeds.ojaidigital.net.
  • HISTORIC LODGE AND RESTAURANT - FULLY EQUIPPED
    Built in 1901, The Crazy Mountain Inn has 11 guest rooms in a town-center building on 7 city lots (.58 acres). The inn and restaurant...
  • ONE WILL: THREE WIVES
    by Edith Tarbescu. "One Will: Three Wives" is packed with a large array of interesting suspects, all of whom could be a murderer ... a...