(Courtesy photo)

The booms and busts in the population of anchovies

California anchovies are almost exclusively sold abroad as food for fish farms and bait for tuna.

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‘Tis the season for Humpback whales in San Francisco Bay. From May through November, the Humpbacks visit our cooler, more temperate waters to feed on anchovies. This is good news for whale lovers, as well as local businesses that depend on abundance of local leviathans.

“On our first trip of the day we found whales several miles off of Muir Beach,” Allison Payne, a naturalist with San Francisco Whale Tours, said. “There were fishing vessels and birds around the whales who were also taking advantage of the anchovies.”

While whales make a big splash, spotting large populations of anchovies should also be exciting. The small fish are an important food source for many of San Francisco’s beloved wildlife species, including sea lions, salmon, Dungeness crabs and brown pelicans.

Unfortunately, anchovies also exhibits rapid cycles of booms and busts in their populations. When the population collapses, like it did between 2013 to 2016, the effects ripple across the ecosystem. Brown pelicans struggled to reproduce and those that did abandoned their chicks. Thousands of sea lion pups were found malnourished and dehydrated on California’s beaches.

These effects may be exacerbated by humans, especially when high fishing rates remain when stocks are in decline. California anchovies are almost exclusively sold abroad as food for fish farms and bait for tuna.

That’s why Oceana, a nonprofit dedicated to ocean conservation, filed suit this month. For years, the organization has pushed the National Marine Fisheries Service to set annual catch limits that account for anchovy boom and bust cycles. This May, the Service issued a final rule that didn’t provide for population drops. The agency has refused despite multiple court orders requiring that it revisit its catch limits based on the best available science on current population sizes. Then, this May, the Service issued a final rule that again didn’t provide for population drops.

“The Service’s rule is inconsistent with the best available science,” Dr. Geoff Shester, the California Campaign Director and Senior Scientist with Oceana, told me. “It’s a shame we’re spending millions of taxpayer dollars on elaborate ships that are coming up with world class population estimates, and managers refuse to use the data in estimating their standards.”

Over two decades ago, when the anchovy management regime was developed, it was harder to know how many of the small, silver fish were swimming along the Pacific Coast. Now, scientists have a much better idea. Researchers with the National Oceanic and Atmospheric Administration travel from Vancouver Island, Canada to the United States-Mexico border every summer to survey populations of anchovies, sardines and other fish.

Of course, not everyone believes these surveys present an accurate picture of anchovy populations. Fishing groups have asserted the surveys miss most of the anchovy in California state waters where virtually all young anchovy live. These groups have been working with the state Department of Fish and Wildlife to develop nearshore estimates.

“Not just fishermen, but also independent scientists said these surveys can not be used to estimate the anchovy population until they include an estimate of nearshore abundance,” Diane Pleschner-Steele, executive director of the California Wetfish Producers Association, told me.

“A growing body of independent science now finds that this small fishery has negligible impact on the ecosystem.

Pleschner-Steel is certainly right on one point: the anchovy fishery is small. This isn’t a case of environmentalists fighting powerful, wealthy corporate interests. The fishermen and women who provide us with the salty fish are working to support themselves and their families now that commercial sardine catches, on which they also rely, have been banned.

But there are many other men and women who are economically dependent on healthy anchovy populations. When the Service considered setting catch limits in 2015, Captain Kate Spencer of Fast Raft Ocean Safaris on Monterey Bay provided the agency with some calculations. According to her math, one humpback whale eats up to a ton of anchovies in 24 hours. While that ton could be caught and sold by fishermen for $100, it equates to between $1,000 to $3,000 per day for whale watchers.

“The socio-economic value of anchovy left in the water attracting whales is huge,” she wrote.

Setting catch limits for a fish that plays such a critical role in the environment and economy can’t be a simple task. But it’s hard to feel like Oceana is wrong for pushing to ensure catch limits reflect the best science. If we want to continue spending our summers eating salmon and watching Humpback whales, we’re going to need to carefully protect the ecosystem they need to survive.

Robyn Purchia is an environmental attorney, environmental blogger and environmental activist who hikes, gardens and tree hugs in her spare time. She is a guest opinion columnist and her point of view is not necessarily that of the Examiner. Check her out at robynpurchia.com

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