10/5/11: Nature Doesn’t Cooperate with Judge’s Delta Smelt Ruling

Two months ago, a federal court in Fresno prohibited releasing sufficient flows to protect the delta smelt – the Bay-Delta estuary’s most endangered fish – despite the fact that 2011 is one of the wettest years in recent memory. Sadly, it looked like a rare opportunity to help the species rebound was going to be lost. But nature isn’t cooperating with the judge, and the good flow conditions are supporting the highest numbers of delta smelt found since 2003. While the population is still only a fraction of its former abundance, this recent increase represents a ray of hope for a species on the brink of extinction.

On August 31, Judge Oliver Wanger (in one of his last decisions before returning to private practice) enjoined the U.S. government from fully implementing the fall outflow provision of the biological opinion for delta smelt, claiming scientific uncertainty and finding that his ruling would enable the export of an additional 200,000 acre-feet of water to San Joaquin Valley agribusiness and Southern California cities. (The giant Delta export facilities pump 5 – 6 million acre-feet on average each year).

The biological opinion spells out the minimally protective steps necessary to control operation of the Delta export pumps in order to prevent extinction of delta smelt, which is listed under the Endangered Species Act. The U.S. Fish and Wildlife Service included the requirement to increase freshwater outflow from the Delta to San Francisco Bay during the fall of wetter years because of the strong relationship between the distribution of delta smelt and fall outflow (the proposed outflows are designed to make sufficient smelt habitat accessible to the species). This and other protections were won after The Bay Institute and its allies successfully challenged the old, grossly inadequate regulations and identified the actions necessary to save the species from extinction.

Most scientists working on delta smelt protection – with the exception of consultants working for the exporters –support actions that improve fall outflow. Scientists from the major state and federal resource and water agencies working in the Delta – and this same judge – have previously stated that the basis for this action is strong. And an independent scientific review concluded earlier this year that implementing the fall outflow requirement in the wet conditions of 2011 represents “an unusual opportunity for a quantum leap in our fundamental understanding” of delta smelt biology and management.

Happily, this year’s improved snowpack and the recent rains mean that the biological opinion’s fall outflows are occurring – albeit courtesy of nature and not of Judge Wanger. The fall midwater trawl index for September and October was 104 – a mere fraction of the high index numbers experienced in past decades but a marked improvement over the index values of the last few years (44 in 2004; 12 in 2005; 36 in 2006; 13 in 2007; 7 in 2008; 4 in 2009; and 18 in 2010). You can learn more about the issue by reading expert testimony by The Bay Institute’s scientists about the scientific basis for improving fall outflow (note testimony on pages 27-37).