Lookout Slough, a 3,400-acre wetland on the edge of the Sacramento-San Joaquin Delta in central California, is ringed with aquatic plants, pulsing with tides from San Francisco Bay, and home to dozens of species of fish, amphibians, reptiles and birds. Until two years ago, it was parched former farmland, cut off from the Sacramento River’s floodplain by a 26-foot-tall levee.
This transformation, the delta’s largest tidal restoration project, was prompted by the decline of the Delta smelt, a fish barely as long as an index finger. Adapted to the delta’s brackish tides over thousands of years, the smelt is considered a strong indicator of ecological health. No smelt means there’s not enough phytoplankton or zooplankton in the water to sustain the species, and therefore less food for birds and larger fish.
Charlotte Biggs, program manager for the California Department of Water Resources (DWR), compared the smelt’s role in the delta’s wetlands to the blood tests that tell humans about “bigger things that may be going on in your body.” The question now is whether restoring wetlands like Lookout Slough can revive the Delta smelt.
Source: High Country News