Remaking California’s Central Valley wetlands was a complicated project that took much of the 20th century. Resurrected from degraded farmland and cash-strapped gun clubs, assembled by bulldozer and backhoe, the current patchwork of national wildlife refuges, state wildlife areas, and county preserves is much diminished from the four million acres of primeval wetlands that spanned the Central Valley before it was farmed. Nevertheless, these habitats are ecologically significant on a hemispheric level, serving 60 percent of migratory waterfowl on the Pacific Flyway, including three million ducks, two million geese, and a half million shorebirds. Their restoration has lured hungry birds away from agricultural fields, created wilderness access for rural communities, and returned endangered species to viable numbers. Decades before the spread of concepts like the Anthropocene and reconciliation ecology, refuge managers were devising ways to sustain ecological systems that had been dramatically altered.
Decades before the spread of concepts like the Anthropocene, refuge managers were devising ways to sustain ecological systems that had been dramatically altered.
Today there are about 206,000 acres of actively managed wetlands in the Central Valley, a third of which are publicly owned. Some, like the Sacramento and San Luis National Wildlife Refuges, are popular with urban tourists, featuring visitor centers, well-maintained auto tours, and interpretive signage; others, like the state-run Mendota and Volta Wildlife Areas, are managed for hunting rather than wildlife observation. Roadside wilderness zones, irrigation canals, and levees along the refuge boundaries provide opportunities for unsanctioned recreation and foraging.
Maintaining functional wetlands in a 21st-century landscape dominated by agriculture and cities requires a host of hard and soft infrastructures. Canals, pumps, and sluice gates provide critical life support, and the lands are irrigated and tilled in seasonal cycles to essentially farm wildlife. Reams of laws and regulations scaffold the system. The federal Central Valley Project Improvement Act (1992) — perhaps the most critical of these laws — establishes a minimum water supply for nineteen valley refuges, though this water can be unaffordable, undeliverable, and politically contested.
The videos published here record seasonal shifts at thirteen managed wetlands in the valley’s major drain basins — the verdurous Sacramento River Valley, the extensively re-engineered San Joaquin River floodplain, and the agro-industrial Tulare Basin. My ongoing documentary project Cultivated Ecologies observes interactions between humans, wildlife, and infrastructure in these novel ecosystems.
The Tulare Basin
Cynthia Hooper, Cultivated Ecologies: The Tulare Basin, 2018.
California’s largest expanse of primeval wetlands was found in the Tulare Basin. Once enormous Tulare Lake anchored these wetlands and episodically flooded northward to the San Joaquin River on its way to the ocean. Tulare Lake was drained by the turn of the 20th century, but sections of its now-leveed footprint can still rise from the dead during periods of exceptional rainfall. Industrial agriculture completely dominates this basin, enabled by the California Aqueduct along the west side, the Friant-Kern Canal on the east, and copious groundwater pumping. The Tulare Basin now has no natural outlet and more than 99 percent of its wetlands are gone.
The Kern National Wildlife Refuge features seasonal wetlands that are flooded each winter with CVPIA water, as well as grassland, scrubland, and alkali playa that rely mostly on scarce rainfall. Plenty of birds find a home here, including up to 6,000 nesting White-faced Ibis that commandeer the place each spring. Like much of the Tulare Basin, parts of this refuge suffer from surface and groundwater contamination by salt from extensive irrigation. Kern also sits uncomfortably close to more than 3,000 acres of toxic evaporation ponds that many birds find appealing — particularly migratory shorebirds like Black-necked Stilts and American Avocets. Tactics for keeping the birds away include maintaining a 300-acre compensation habitat for alternative nesting and foraging. This extremely subtle wilderness, near the original north shore of Tulare Lake, almost invisibly blends into the row crops that surround it.
The Tulare Basin’s other significant wetlands include the Mendota Wildlife Area, a state refuge managed for hunting and for growing irrigated crops of safflower and watergrass to feed its huge population of birds; and the isolated Pixley National Wildlife Refuge, surrounded by dairies and field crops and dependent on a single source of management water from a CVPIA-funded well. Pixley’s seasonal wetlands, moist soil units, and upland habitat support a dedicated flock of up to 7,000 Sandhill cranes.