Federal Report: Poor Ocean and River Conditions Spurred Salmon Collapse

Federal Report: Poor Ocean and River Conditions Spurred Sacramento Salmon Collapse

by Dan Bacher

The collapse of the Sacramento River fall Chinook salmon population is the result of a combination of both poor ocean and river conditions, according to a report released by the National Marine Fisheries Service (NMFS) on Wednesday.

This conclusion amounts to a nuanced break with the contention by state and federal government officials last year that “ocean conditions” were the “likely culprit” behind the unprecedented salmon decline, in an obvious attempt to underplay the destructive role that Central Valley dam operations and Delta water exports have on the run.

Although representatives of fishing and environmental groups were encouraged that the report acknowledged the impact of adverse freshwater conditions on salmon, they were critical of the scientists’ apparent refusal to fully investigate the key role of water exports and decline in water quality resulting from Central Valley dam operations in the report. Steve Lindley, the lead author and a research ecologist at National Oceanic and Atmospheric Administration, and 25 other scientists contributed to the report.

The report still points to ocean conditions being the immediate cause of the collapse. “The likely cause of the SRFC collapse lies at the intersection of an unusually large drop in abundance and poor environmental conditions,” the report stated. “Using this framework, all of the evidence that we could find points to ocean conditions as being the proximate cause of the poor performance of the 2004 and 2005 broods of SRFC.”

At the same time, the scientists acknowledge the role of the degradation of Central Valley rivers and California Delta in the collapse. “The rapid and likely temporary deterioration in ocean conditions is acting on top of a long-term, steady degradation of the freshwater and estuarine environment,” according to the study.

The report was released as the Pacific Fishery Management Council (PFMC) is reviewing its very limited options for ocean salmon seasons this year. Last year commercial and recreational Chinook salmon fisheries was completely closed in California ocean waters and most of Oregon, since the spawning escapement of SRFC in 2007 was estimated at only 88,000 fish. The Sacramento River fall Chinook is the driver of West Coast salmon fisheries.

The situation was even more catastrophic in 2008, when a record low number of 66,000 spawners returned to the Central Valley rivers and fish hatcheries. This is well below the PFMC’s escapement conservation goal of 122,000-180,000 fish. It is expected that all recreational and commercial fishing will be closed this year, with the possible exception of a token 10-day season for Klamath River Chinook off California’s North Coast and Southern Oregon.

The report says that a “broad body of evidence” suggests that “anomalous conditions” in the coastal ocean in 2005 and 2006 resulted in unusually poor survival of the 2004 and 2005 broods of the fall run Chinook.

“Both broods entered the ocean during periods of weak upwelling, warm sea surface temperatures, and low densities of prey items,” according to the report. “Individuals from the 2004 brood sampled in the Gulf of the Farallones were in poor physical condition, indicating that feeding conditions were poor in the spring of 2005 (unfortunately, comparable data do not exist for the 2005 brood)."

Unfortunately, while admitting that poor ocean and fresh water conditions led to the collapse, the report incongruously claims that freshwater conditions were “not unusual” in 2005 and 2006!

“The evidence pointed to ocean conditions as the proximate cause because conditions in freshwater were not unusual, and a measure of abundance at the entrance to the estuary showed that, up until that point, these broods were at or near normal levels of abundance,” the report stated. “At some time and place between this point and recruitment to the fishery at age two, unusually large fractions of these broods perished.”

This statement isn’t backed up by an actual review of the Department of Water Resources data documenting record water exports out of the estuary the same years that juvenile salmon were migrating through the Delta. In fact, the hydrology of the estuary was completely altered in the years that naturally spawned Chinook salmon went to sea.

Record water export levels of 6.3 million acre-feet (MAF) occurred in 2003, 2004 (6.1 MAF), 2005 (6.5 MAF) and 2006 (6.3 MAF). Exports averaged 4.6 MAF annually between 1990 and 1999 and increased to an average of 6 MAF between 2000 and 2007, a rise of almost 30 percent, according to Bill Jennings, executive director of the California Sportfishing Protection Alliance (CSPA).

The scientists also admitted that the cessation of net-pen acclimatization of hatchery salmon in San Pablo Bay in 2006 “may have contributed to the especially poor estuarine and marine survival of the 2005 brood fish.” Assemblyman Jared Huffman (D-San Rafael), Water for Fish, CSPA and other groups were instrumental in spurring the DFG to put the acclimation pen program back in operation in 2007 and 2008.

The scientists also said that fishery management played a role in the low numbers of returning salmon – “escapement”- in 2007. The PFMC forecast an escapement of 265,000 SRFC adults in 2007 when the actual escapement was only 87,900.

“Had the pre-season ocean abundance forecast been more accurate and fishing opportunity further constrained by management regulation, the escapement goal could have been met in 2007,” the report stated.

In addition, the study noted that the “long-standing and ongoing degradation of freshwater and estuarine habitats and the subsequent heavy reliance on hatchery production were also likely contributors to the collapse of the stock."

Representatives of fishing and environmental groups were dismayed that the report didn't include more discussion of the need to maintain freshwater flows in the river and Delta to recover salmon populations.

“I’m pretty disappointed by the report,” responded Zeke Grader, executive director of the Pacific Coast Federation of Fisherman’s Association after reviewing the document. “I don’t think that the agency looked in depth at the impact of diversions and water exports upon the destruction of Sacramento River salmon population. They didn’t review the historical data that shows a direct correlation between water diversions out of the estuary and salmon declines.”

Grader said the agency also failed to explore the relationship between the declines of California Delta pelagic species – delta smelt, longfin smelt, juvenile striped bass and threadfin shad – and Sacramento River Chinook salmon. Nor did they look at the impact of increasingly bad water quality, spurred by the refusal of the state of California to impose water pollution standards upon agriculture, or two recent reports written by NMFS that implicate water exports and pesticides as major factors in the salmon collapse.

The recently rewritten draft “biological opinion” by NMFS, ordered by a federal judge, concludes that increases in freshwater exports out of the California Delta and the operation of Shasta Dam and other reservoirs have led to the collapse of Central Valley spring run and winter run salmon, Central Valley steelhead, green sturgeon and the southern resident orca population. The killer whales, now estimated to number less than 90 individuals, feed heavily upon Sacramento Chinooks and other runs of salmon.

That study reveals that only 8% of the juvenile salmon (smolts) make it to the West Delta - when the Sacramento River salmon survival of 20% is combined with the Delta survival of 40%.

“The main deficiency of the recent report is that the agency is still not talking about what needs to be done to restore salmon,” said Tina Swanson, a fishery scientist and executive director of the Bay Institute. She criticized the agency’s “lack of will” in taking actions to recover salmon, including changes in the operation of state and federal projects.

Nonetheless, the report, in spite of its many flaws shows how river and ocean conditions teamed up to create a "Perfect Storm" that resulted in the collapse of Central Valley Chinooks. “The report demonstrates how dam operations and loss of habitat have brought Sacramento River fall Chinooks to the point where bad ocean conditions could precipitate a collapse,” said Bill Jennings. “If it wasn’t for the dams, diversions and water exports, the salmon fisheries could easily rebound within a year or two.”

To read the report, “What caused the Sacramento River fall Chinook stock collapse?” go to: http://swr.nmfs.noaa.gov/media/SalmonDeclineReport.pdf

For more information about what you can do to save Sacramento salmon, southern resident killer whales and the Delta, go to http://www.calsport.org or http://www.water4fish.org.