Saving Seafood

Anchovy Dominated Diets off the West Coast Pose New Dangers for Salmon

June 26, 2025 — A vitamin deficiency likely killed as many as half of newly hatched fry of endangered winter-run Chinook salmon in the Sacramento River in 2020 and 2021. These new findings were published in the Proceedings of the National Academy of Sciences.

The deficiency of thiamine, or Vitamin B1, is linked to large-scale shifts in the ocean ecosystem. These shifts changed the prey adult salmon consume before they return to West Coast rivers to spawn, scientists reported. They said the longtime loss of habitat and water has already weakened many California salmon populations. Further declines from thiamine deficiency or other impacts may lead to their extinction.

The deficiency syndrome can also affect salmon runs like the Central Valley’s fall-run that once supported valuable commercial fisheries across California. They have since dwindled to the point that commercial ocean salmon fishing in California has been closed for the last 3 years.

Read the full article at NOAA Fisheries

Study Proposes New Explanation for California Anchovy Booms and Busts

December 21, 2023 — New research from Scripps and NOAA scientists has discovered ecological correlations that could help explain the booms and busts of California’s anchovy population. If the correlations hold up to further research, they could one day help inform management of California’s anchovy fishery and improve conservation.

The Northern Anchovy (Engraulis mordax) is a crucial food source for much of California’s most conspicuous marine life—including droves of sea lions, pods of dolphins, lucrative tuna fisheries, and throngs of whales. But one of the hallmarks of the anchovy population off California is the cycle of booms and busts that can last for more than a decade. These ups and downs reverberate through the entire marine ecosystem, with busts at times contributing to starving sea lion pups or leading brown pelicans to abandon their chicks.

Exactly what drives these booms and busts has remained elusive despite decades of scientific study, notably by the CalCOFI research program which is cooperatively run by UC San Diego’s Scripps Institution of Oceanography, the National Oceanic and Atmospheric Administration (NOAA), and the California Department of Fish and Wildlife. The program surveys marine ecosystems up and down the California coast and is one of the largest and longest ocean monitoring programs in the world.

The study, published in Nature Communications and funded by NOAA and the National Science Foundation, points to the marine ecosystem surrounding newly hatched anchovies known as larvae. The researchers analyzed 45 years-worth of anchovy larvae collected during CalCOFI surveys and found that the length of the food chain supporting the larvae strongly correlates with anchovy population booms and busts. Specifically, shorter food chains preceded booms and longer ones preceded busts. Shorter larval food chains have fewer steps of one animal eating another between the photosynthetic phytoplankton harvesting the sun’s energy at the base of the food chain and the larvae, which eat mostly zooplankton.

Read the full article at ECO Magazine

Judge rules for Oceana in California anchovy dispute

June 20, 2018 — Just how many anchovies are there off the northern coast of California and are there enough to fish commercially?

Environmental activist group Oceana and the National Marine Fisheries Service (NMFS) have different answers to those questions, and a federal judge’s ruling recently favored Oceana’s view, reducing opportunities for California fishermen.

At issue is the science that NMFS relied on in reaching a 2016 decision to set the total allowable catch (TAC) for northern California anchovy at 25,000 metric tons. The agency set that limit — even though landings typically only total less than a third of that, 7,300t — judging the stock’s maximum sustainable yield to be 123,000t, and calculating an acceptable biological catch of 100,000t. The TAC was set, conservatively, the agency said, at a fourth of that level.

However, after the 2016 rule was adopted, Oceana sued NMFS in federal court arguing that the rule violated principles established in the the Magnuson-Stevens Act because the agency failed “to articulate the scientific basis for this catch limit”.

Read the full story at Undercurrent News