C-WIN: Fisheries expert: Fish & Game Commission’s move to list white sturgeon is a red herring

The California Fish & Game Commission’s recent decision to initiate a listing process for white sturgeon under the state Endangered Species Act identified overfishing as a primary threat to the beleaguered species and included an immediate angling closure. But the real reason for the gigantic fish’s decline, said a fisheries biologist, is  excessive water diversions from the Sacramento-San Joaquin Delta.

Tom Cannon, a fisheries expert and a consultant for the California Water Impact Network, recently concluded a study of white sturgeon “recruitment” – the number of young fish produced each year.

“While the Fish and Game Commission cited overfishing as a primary concern, angling has had minimal impact on sturgeon,” Cannon said. “The real issue is the lack of freshwater flows through the Delta.”

Cannon noted the insufficient flows have had two deleterious effects on sturgeon. First, they’ve been implicated in massive die-offs of adult sturgeon in San Francisco Bay in recent years.

“What happens is the water in the Delta ‘cooks’ during low summer flows and reaches temperatures lethal to sturgeon,” said Cannon. “The water is nutrient laden and anoxic [low in oxygen]. At neap tide conditions, it empties into the bay, creating red tide conditions that kill adult fish outright.”

Even more disastrous for the species is the lack of recruitment, Cannon continued.

“Recruitment surveys for 2023 documented a record number of young fish,” Cannon said. “Why is that, given the trouble sturgeon are in? So then I analyzed records going back over the past decade. And in the last 10 years, there were only three years where there were any significant number of young sturgeon ­ – 2023, 2017 and 2011. All of those were very wet years.”

What that shows, said Cannon, is that sturgeon need adequate through-Delta flows to reproduce and survive. And until the Newsom Administration acknowledges that essential fact, any efforts to save the sturgeon – including ESA listings and fishing closures – are worthless.

“The closure is a distraction, a red herring, so to speak,” Cannon said of the Commission’s recent moves. “The state’s priority – maximum water deliveries to San Joaquin Valley corporate farms at the expense of the Delta and its fisheries – remains unchanged. It’s both an outrage and a tragedy.”