Delta still ailing despite wetter year


By Mike Taugher
CONTRA COSTA TIMES
Wednesday, August 30, 2006


Despite an unusually wet year, the Delta's health continued its decline with the population of young striped bass hitting a new low, records show.

Taken with survey results released in early July that showed Delta smelt also at extremely low levels, the final summer figures show that the Delta is not responding to favorable weather patterns.

The Delta's faltering health is alarming environmentalists and anglers and threatens water supplies from the Bay Area to Southern California because of conflict between the state's dependence on Delta water and environmental needs.

With the cause of the four-year-old crisis still unclear, the state has ideas but no plan to reverse the decline.

Instead, state water officials are preparing a report for release Oct. 1 that is expected to suggest steps that could be taken.

Among the proposals that might be included are growing more algae to boost the Delta food supply, raising fish in hatcheries or temporarily increasing the flow of water through the Delta.

None of those ideas appears likely to do much, and critics are growing impatient.

"I'm extremely concerned about (the summer survey numbers), but I'm much more concerned about the lack of action on the (Schwarzenegger) administration's part," said Assemblywoman Lois Wolk, D-Davis, who is chairwoman of the assembly Committee on Water, Parks and Wildlife. "The Delta is in crisis and there doesn't seem to be any sense of crisis on their part."

Since about 2002, the open-water fish species of the Delta have been in severe decline. The crash was discovered last year by scientists who, three years into it, had enough data to confirm the trend and rule out known explanations.

With abundant rain this spring, some water officials held out hope that summer fish surveys would bring a glimmer of good news. They did not.

"They're very discouraging," said Barbara McDonnell, chief of the Department of Water Resources environmental services division. "We had hoped with a good water year that we would have seen some kind of improvement."

Recently posted final figures for this summer show the young-of-the-year striped bass index at 0.5, down from 0.9 last year. The Delta smelt index hit 0.4, up just a tick from 0.3 last year.

Those figures do not translate into Delta fish population estimates, but they do offer a way to compare the health of fish populations over the years. And they show the Delta's fish populations are extremely low.

"It was a great spring. Ten years ago, I would expect us to be up to our armpits in fish," said Bruce Herbold, a fisheries biologist at the U.S. Environmental Protection Agency. "It's really disturbing that the wet year didn't buy us some time. ... The add-water-and-get-fish recipe isn't working."

The decline has been a long one for young striped bass. The index exceeded 100 a couple of times in the 1960s and only rarely dipped into the single digits until the late 1980s. It sank below 1.0 for the first time in 2004.

Anglers have grown deeply concerned about the lack of young fish, though the adult striped bass population has not suffered the same nose-dive.

"That's a wake-up call to us," said Gene Buchholz, owner of the Hook, Line and Sinker tackle shop in Oakley. Although it is unclear whether the adult striped bass population is in decline, some anglers say it is.

"This time (of year) five, 10, 20 years ago, you'd be able to catch stripers all over. They're not doing it now," Buchholz said

The Delta forms a triangle the size of Yosemite National Park with points at Antioch in the west, Tracy in the south and Sacramento in the north.

The state's largest rivers carry snowmelt and rain into the Delta, where pumps send water to canals supplying farms and cities from Concord to San Diego. Two-in-three Californians get at least some of their tap water from the Delta.

Environmentalists and anglers contend that excessive pumping is the root of the Delta's environmental problems. Water not sent south flows through the Delta into San Francisco Bay.

"I don't know where the edge of no return is, but if we're not there, we're soon approaching" it, said Bill Jennings, executive director of the California Sportfishing Protection Alliance.

Scientists believe the collapse is a result of some combination of toxic pollution, water exports and invasive species.

One leading theory developed by the Contra Costa Water District holds that a shift in the timing of water deliveries through the Delta about a decade ago has contributed to increased salinity in the fall, creating beneficial conditions for an invasive clam that arrived during the 1980s. The clam appears to be consuming much of the plankton that the fish need for food.

If the Contra Costa Water District's theory is correct, it might make sense to increase the flow of water through the Delta in the fall to push back brackish water from San Francisco Bay, reduce salinity and possibly shrink the clam beds.

But salinity is already expected to be relatively low this fall because of the wet year. Further reducing salinity might require an impossibly large amount of water, according to the water resources department.

"I'm looking at how much water it would take to affect the clams," said McDonnell. "Even if you throw 1 million acre-feet at it, could you even see a difference? It appears it would be an awful lot of water."

Still, increasing fall flows is one of the options that could be included in the department's report to lawmakers that is expected on Oct. 1.

Other ideas under consideration at the water resources department include increasing algae production to boost the food supply. But there is concern that doing so could merely provide more food for harmful clams rather than the starving fish.

Hatchery production, programs to prevent more invasive species from entering the Delta, habitat improvements, altering the timing of water exports and other proposals are also being weighed.

So far, a wholesale reduction of water sent south is not on the list, McDonnell said.

 

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