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Denis Cuff, Bay Area News Group Reporter, is photographed for his Wordpress profile in Pleasanton, Calif., on Thursday, July 28, 2016. (Doug Duran/Bay Area News Group)
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Since 1959 the California Department of Fish and Wildlife (CDFW) has used a combination of scientific techniques to better understand fish populations and the general health of Northern California waterways. Examples include tagging sturgeon, trawling the Delta for smelt, and counting salmon carcasses. CDFW uses data from these strategies and others to help influence operations of the State Water Project and Central Valley Project, ultimately helping decision makers determine water flows. This short video highlights these operations along the Sacramento River and into the Delta, including a smelt survey conducted by Environmental Scientist Felipe la Luz.

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A tiny fish caught in California’s tug of war over water has become harder to find than ever, a state survey found, despite a very wet winter last year that had raised hopes for a bounce back after five years of drought.

Environmentalists say the record-low fall survey for the Delta smelt bolsters the case for sharper limits on water exported from the Sacramento San Joaquin River Delta to San Joaquin Valley farms and many cities in California.

Just last week, however, the Trump administration moved in the opposite direction, serving notice it is beginning a review of alternatives “to maximize” Delta water deliveries that have been restricted by protections for the endangered Delta smelt and other fish.

The 3-inch-long smelt sank to a new low when state crews netted only two fish from September though December in an annual fall survey aimed at gauging the relative abundance of the fish. It was the lowest count since the fall survey began in 1967.

Scientists said the low count was especially disappointing because they had hoped the struggling smelt population would rebound after last winter’s rains flushed more water through the rivers, sloughs and bays where the fish live.

Peter Moyle, a UC Davis professor emeritus, has said for years there may too few Delta smelt left to avert extinction of the once-abundant fish considered an indicator of the environmental health of the Delta. As goes the smelt, according to this analysis, so will follow the salmon and other wild fish.

“This should have been the year of recovery … no such luck,” said Moyle, who has studied the fish for decades. “Delta smelt may be so scarce that adults have a hard time finding one another to spawn, especially in a year with lots of water.”

Moyle said his own surveys in the Suisun Marsh found no smelt.

State officials said they believe the smelt reproduced in the spring, but the baby fish had problems surviving when an unusually hot summer warmed up Delta water too much in July and August.

“The fall survey was disappointing,” said Carl Wilcox, a state Department of Fish and Wildlife policy adviser. He added that he believes the high Delta water temperatures in summer hurt the fish.

Wilcox said that in a more encouraging result, six smelt were found in December in a different type of state survey that sampled for fish closer to the surface.

Wilcox also said that another troubled Delta fish, the Longfin smelt, rebounded well last year during the higher river flow conditions in spring and fall. “If temperature was a factor in the low Delta smelt abundance,” Wilcox said, “it isn’t for Longfin because they have moved into the bay, where water temperatures are influenced by marine conditions and tend to be cooler.”

Netting surveys are done to track relative abundance of smelt from year to year because it’s impossible to count the tiny fish spread out over hundreds of miles of waterways.

EBT-L-SMELT-0107-90Doug Obegi, senior attorney for the Natural Resouces Council, said the record-low smelt survey provides sobering evidence that the species is declining as too much water is exported out of the Delta during dry and wet years to serve cities.

“This is a bad sign,” Obegi said. “It’s a warning that other native fish species could face the same fate.”

When Donald Trump was a presidential candidate in 2016, he ridiculed protections for the Delta smelt that restricted water deliveries.

A representative of the Fresno-based Westlands Water District welcomed the new effort to help stabilize water supplies pumped from the Delta, and said the concerns about the smelt have been overstated.

Johnny Amaral, Westlands deputy general manager, said environmental regulators have focused too much on restricting water deliveries and not enough on fixing other problems for wild fish, such as predators, water pollution, invasive species and habitat damage.

The failure of smelt to recover after a wet winter strongly suggests that it’s unfair to blame lack of water as the only cause of the species’ decline, Amaral said. “We have to look at other stressors,” he said.

The state water board has a great deal of authority over Delta water shipments, and a 1992 federal law called the Central Valley Improvement Act bolsters the state authority over the federal dams, canals and pumps in California to follow state environmental laws.

President Trump, however, and California are fighting over many environmental issues, including climate change and offshore oil exploration.

Obegi said he thinks Trump will try to use his authority over federal water and wildlife agencies and sway with Congress to change rules to get more water for farmers. “He will try to pre-empt the state,” Obegi said. “I foresee a massive assault on California water and wildlife programs through a variety of administrative and legislative ways.”