Striped Bass Attack

by Alastair Bland, March 31, 2010

Striped bass came under direct attack in early March when a Bakersfield Republican introduced legislation that would eliminate all striped bass regula­tions, protection and habitat improvement with the goal of knocking the nonnative species into regional extinction. The bill comes from Assemblymember Jean Fuller under the premise that Chinook salmon numbers have dwindled due to in large part to preda­tion by striped bass. Assembly Bill 2336, assures Fuller, is an effort to bring the Sacramento’s salmon back from the edge.

But striped bass and Chinook salmon thrived side by side for much of the 20th century, say critics of Fuller’s legislation, including biologists and fishing groups. They believe AB 2336 is an attempt to distract the public from what they say is the foremost reason that the Delta’s fisheries are collapsing: water pumps in the Delta that deliver river flows to farmers in the San Joaquin Valley.

John Beuttler, conservation director with the Cali­fornia Sportfishing Protection Alliance considers the bill merely a political tactic.

“This attack is simply another way to misdirect the government away from the real impacts associated with the development and export of the Delta water supplies,” Beuttler wrote in a statement dated March 8.

Biologists who have studied the Delta’s ecosystem for years also say the bill is based on false presump­tions. Dr. Peter Moyle, a fisheries biologist at UC Davis, says there is no evidence indicating that striped bass do or ever did in recent decades pose a serious threat to fishes native to the Bay-Delta system.

“Even when the smelt were abundant, striped bass weren’t eating them,” says Moyle, who has analyzed stomach contents of many striped bass taken from waters populated by salmon and smelt. “They do sometimes eat salmon, but they mostly get hatchery fish. No biologist who understands the Delta system would argue that (predation by stripers on Chinook salmon and Delta smelt) is a valid point.”

But Doug Demko does. As a biologist with the fish­eries consulting firm FishBio working for water districts in the San Joaquin Valley, Demko says that scientists who fail to find salmon in the stomachs of striped bass just aren’t sampling bass from the right places. He says that at Clifton Court Forebay, for example, an average of 85% of salmon that pass by the state water pumps are eaten by striped bass.

“Fish are getting killed by other fish, not the pumps,” says Demko, though he acknowledges that the pumps themselves can draw juvenile salmon where they otherwise wouldn’t go, like backwaters inhabited by striped bass, and he calls the water delivery system in the southern Delta “partially culpable” for the decline of the Chinook salmon.

AB 2336 is a near-replicate of a bill introduced by Fuller 12 months ago with the same stated objective: to eradicate striped bass and help save the Chinook salmon. Demko spoke publicly in support of that bill, which was ultimately rejected by the Assembly’s Committee on Water, Parks and Wildlife, which will review Fuller’s new legislation sometime in April. Other supporters of last year’s bill included the Kern County Water Agency, the Modesto Irrigation Dis­trict, the Metropolitan Water District of Southern California, the Friant Water Authority and the East­ern Municipal Water District. These San Joaquin Valley water users are now backing Assembly Bill 2336.

Skeptics are suspicious.

“In my opinion, this bill is a public diversion to gain more water for corporate agriculture at the expense of the public and the environment of California,” says Dr. David Ostrach, a research scien­tist and striped bass expert who worked until last spring at UC Davis.

A March 11 statement from Fuller’s office con­ceded that water pumping has played a role in the Delta’s environmental problems but stressed that promotion of nonnative predators as valued game fish has contributed to fisheries’ declines. But Chinook salmon and Delta smelt aren’t the only species in the river system now failing, Dr. Ostrach points out; numbers of striped bass themselves have plummeted.

“In fact, the best indicator of a healthy ecosystem would be to have a healthy striped bass population,” said Ostrach. “With them crashing, it indicates that we have serious problems in the Delta ecosystem.”

Moyle doubts that lifting all regulations on striped bass would lead to the species’ disappearance, anyway, and he also feels that encouraging the consumption of a fish known to contain high levels of mercury is irre­sponsible and becomes “a social justice issue.”

“But these people are willing to say anything except that the pumps are the big problem,” says Moyle. “This bill is a ploy.” ¥¥

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