Waterfowl `Rest Stop' Endangered California's Dwindling Wetlands Areas Struggle against Water Shortages and Urban Creep
Michael Hodgson, Monitor, The Christian Science Monitor
SITUATED in the Central Valley of California, wetlands shelter more than 30 percent of the Pacific Flyway's wintering populations of duck and geese. Yet, if you are a duck, flying into this rest stop is like flying into a nightmare - habitat without enough water, a dwindling food supply, poisonous runoffs, and increasing urban encroachment.
For migrating waterfowl, one of the primary wetlands in the Central Valley is the Grasslands. Managed by the Grasslands Resource Conservation District and the Grasslands Water District (GWD), the area is a patchwork quilt of private duck clubs and state and federal refuges, accounting for more than 75,000 acres of habitat - approximately 25 percent of the freshwater habitat in California.
This public/private partnership is responsible for saving much of California's meager remaining wetlands. Yet, the Grasslands can't get enough water to flood fields, grow wild food, or fill its pools, even in the best of times.
By contract, the water district receives 50,000 acre feet of water annually from the Central Valley Project, a federal agency that owns and manages water rights in the Valley. Until recently, the water district - like many other wetland areas - relied on return flows from agriculture to supplement the contract water, up to 100,000 acre feet. That was until selenium salt contamination was discovered in 1983.
The agricultural drain water used to flood the Kesterson National Wildlife Refuge was found to be loaded with selenium. Wildlife biologists linked selenium to massive die-offs, deformities, and infertility in waterfowl. Drain water could no longer be used to irrigate and flood the wetlands, and no other water was available to replace it.
With the loss of two-thirds of the water supply, the Grasslands cannot continue to support the migratory bird population and the wildlife that inhabit it.
"Each year it has gotten more difficult to obtain needed water. Unless we can find additional water sources this year, we run the very real risk of drying up by February and being unable to provide habitat for late-winter residents or irrigate for food production," says Don Marciochi, the water district's general manager.
Conservationists see this as a near disaster for the thousands of birds and several endangered wildlife species, among them the San Joaquin kit fox and the peregrine falcon, that use the Grasslands year round.
"The Bureau of Reclamation's Refuge Water Supply Investigation recommended 180,000 acre feet (of water) per year for optimum management of the wetlands," says Tim Poole, wildlife biologist for the Grasslands conservation district. "This year, we have managed to scrape together just 67,000 acre feet."
Gary Zahm, United States Fish and Wildlife Service federal refuges manager, says that, "Because of the lack of guaranteed water, they (GWD) are forced to take the water when they can get it, in one lump delivery, which is about the very worst way to manage a wetlands resource."
Further complicating the situation is that the federal contract to deliver water is subject to reduction in drought years. In a long line demanding water deliveries, privately managed wetlands and refuges wait at the end. As high-priority agribusiness users absorb the contractual supplies, the wetlands and refuges dry up, according to Poole.
"Our water supply is a tenuous one," says Mr. Marciochi. "When we receive less than 50,000 acre feet from the government, as we did this year, we are forced to go begging for any available surplus water from sources like the Bureau of Reclamation and other water and irrigation districts."
The problem has worsened through four years of California drought. From the air, vast areas of the Grasslands, once a natural flood plain, consist of brown vegetation and dry alkali flats - certainly no welcome mat for migrating waterfowl. …