Emergency Petition for Change in Federal Listing as Smelt Population Collapses
San Francisco, CA (March 8, 2005) -- The Center for Biological Diversity, the Bay Institute, and the Natural Resources Defense Council (NRDC) today submitted a 42-page petition to the U.S. Fish and Wildlife Service (USFWS) requesting emergency listing of the delta smelt (Hypomesus transpacificus) as an endangered species under the Endangered Species Act (ESA).
The delta smelt is a small, nearly translucent fish found only in the upper San Francisco Bay and Sacramento-San Joaquin Delta. It was once one of the most common and abundant of the Delta's open water fishes, but in the 1980s its population declined by more than 80 percent. The species was listed as threatened under the ESA in 1993. In recent years the delta smelt population has collapsed again: in 2005, the second consecutive year of record low numbers, its abundance was only 2.4 percent of that measured in 1993.
Delta smelt spend their entire lives in the Delta, the west coast's largest estuary, swimming in shallow open waters at the interface of inflowing fresh water from the Sacramento and San Joaquin Rivers and salt water from the ocean. In 1993 USFWS identified multiple threats to the species, including export of fresh water from the Delta, loss of habitat, impaired water quality from pesticides and other pollutants, and competition and predation from introduced species.
Just two years ago, when USFWS completed a status review of the species, the agency concluded that most of these threats remained, and in some cases had worsened. New analyses since then show that recent record-high Delta water exports are related to the delta smelt population decline. Recently published population viability analyses indicate that the species has a 50 percent probability of going extinct in the next 20 years. However, despite this new information and the current record-low population numbers, neither USFWS nor other agencies charged with protecting the smelt and its habitat have taken major actions to reverse the decline.
"The science is clear and compelling. Delta smelt, one of the best indicators of environmental conditions in the estuary, is in critical condition and for the most part we know the reasons why," said Dr. Tina Swanson, Senior Scientist for the Bay Institute. "It's time for the state and federal resource agencies to apply this information to protect this species and its habitat--before it's too late."
The delta smelt is not the only fish species at risk of extinction in the Delta. Since 2002 scientists have also documented catastrophic declines of longfin smelt, threadfin shad and striped bass, and numbers of white and green sturgeon in the Bay and Sacramento River have fallen to alarmingly low levels. The declines are thought to be due to the combined effects of Delta water management and exports, pollution from toxic chemicals and impacts of introduced species on the Delta's planktonic food web, the same factors identified by USFWS as threats to the smelt.
"Delta smelt are on a rapid trajectory toward extinction and clearly need increased federal protections," said Jeff Miller of the Center for Biological Diversity. "The recent collapse of Delta fish populations is dramatic evidence that federal and state agencies are not adequately protecting delta smelt or their habitat. Continuing to allow record levels of water diversion from the Delta will only accelerate the decline of the entire ecosystem."
The Delta, an essential part of the delta smelt's habitat, is a major hub for California's water system. The State Water Project, federal Central Valley Project and thousands of private water diversions take as much as 65 percent of the Delta's total freshwater inflow, killing both spawning adult delta smelt and their young in pumps and diversions. At times, pumping levels are so high they reverse flow in the San Joaquin River, confusing and delaying adult fish migrating upstream, impairing downstream transport of larval and juvenile delta smelt from the upper estuary to their brackish water rearing habitat, and drawing water and fish into the pumps. Hydraulic models indicate that when water export rates are high, virtually all young smelt in the southern Delta are sucked into the pumps. The recent decline of Delta fish species coincides with significant increases in water exports by the state and federal water projects (seasonal exports in the 2000s are up to 48 percent higher than in the early 1990s) and higher mortality of smelt at the pumps. The four highest years of water exports from the Delta have occurred since 2000.
"The delta smelt is a canary in the coal mine, and its plummeting numbers show that the Delta is on the verge of collapse," said Kate Poole, senior attorney with NRDC. "Urgent action is needed to protect Delta habitat and water quality, for the benefit of the smelt and the 20 million Californians who depend on the Delta for clean drinking water."
Despite crashing Delta fish populations, state and federal agencies are in the process of approving increased water diversion and storage projects that will exacerbate current conditions for delta smelt, likely increase mortality of smelt and further alter their habitat. The proposed "South Delta Improvements Program" will increase Delta water exports and install permanent tidal barriers, modifying Delta flow patterns and degrading smelt habitat. The CALFED Bay-Delta Program, promoted as a solution to reducing the negative impacts of the federal and state water projects on fish and wildlife, has proven ineffective and now has largely collapsed.
In September 2005, just before scientists announced that Delta fisheries were declining precipitously, Rep. Dick Pombo (R-CA), Chairman of the House Resources Committee, passed H.R. 3824, a bill that would gut the Endangered Species Act by systematically removing every proven recovery tool for imperiled species--including a provision to eliminate protected "critical habitat." Pombo's bill would make it more difficult to recover and restore the Delta ecosystem and its fisheries.
More information regarding the delta smelt is available on the CBD web site.