When it comes to the number of sardines off the West Coast right now, only one thing is not in dispute: They are at the lowest level scientists have seen in decades.
On April 8, the Pacific Fishery Management Council – a body of appointed officials that regulates fisheries off the West Coast – will be presented with the draft assessment of the sardine population from roughly southern California to Canada. The news it brings is neither good for fishermen nor the local marine ecosystem: The estimated number of sardines in July 2018 – which dictates policy for the 2018-19 fishing year – is 52,065 metric tons, an approximately 97-percent drop from 2006, the most recent peak.
The cutoff for when sardine fishing can occur is when the estimated population is at least 150,000 metric tons, which means the fishery will be closed for the fourth consecutive year.
What is in dispute: the accuracy of the population assessment, and how we got here. On one side, conservation nonprofit Oceana believes the assessment could be too high, and that sardines were pushed to this point due to overfishing when the numbers were low.
On the other side, advocates for fishermen believe there are far more sardines in the water than estimated, and that the estimates are not using the best available methods to make projections.
Currently, the method employed by scientists from the National Oceanic and Atmospheric Administration is to do months-long acoustic surveys off the coastline to measure sardine biomass.
Diane Pleschner-Steele, executive director of the California Wetfish Producers Association, believes that method is flawed and doesn’t accurately capture the sardines close to the shore – NOAA uses large boats that can’t come in too close.
“It doesn’t pass the straight-face test,” she says. “There’s way more than [52,000]. That’s a joke, a very painful joke.”
Geoff Shester, a senior scientist with Oceana, also believes the numbers are painful, but for altogether different reasons. “It’s our worst fears unfolding in front of us, and coming true,” he says, adding that he thinks fishing as late as 2014 drove sardines – an important food source for marine mammals and some sea birds – to the brink.
Even in the absence of fishing, the population of sardines fluctuates wildly based on environmental conditions. Until recently, it was thought ocean temperature was the key determining factor, but even that has been thrown into question: Sardines were believed to favor warmer water, but they continued to plummet despite recent warming.
Also a question is whether sardines were overfished before the fishery closed in 2015. In advance of a PFMC meeting in 2013, Kristen Koch, then-deputy director of NOAA’s Southwest Fisheries Science Center, wrote a letter to the council informing them that in NOAA’s opinion, the sardine fishery “is not currently in a state of imminent collapse,” despite a 2012 paper co-authored by a NOAA scientist, David Demer, arguing that it was.
Demer, it’s turned out, was right.
Shester believes fishing when numbers were declining expedited that collapse, but Kevin Hill, a NOAA biologist who helped author the population estimate, says that’s speculative. He’s confident the population will rebound.