It has been an exceptionally good year for whale watching in California. In past seasons, sightseers off Monterey typically spotted two or three humpbacks on a single afternoon at sea. This past September, October, November, and December, whale watchers were treated to more than 50 at a time. Dozens of killer whales frolicked in the same area throughout the fall. In December, a total of 364 gray whales were counted migrating south past Palos Verdes—double the 182 spotted there in December 2012.
California has witnessed a veritable explosion of sea life over the past six months, and whales aren't the only ones making waves. Environmental scientists said in December that they were seeing "unprecedented" numbers of brown pelicans in the San Francisco Bay Area. It's been "a months-long carnival of lunging humpback whales, bird clouds, dolphin wizardry, frenzied sea lions, playful killer whales and even visits from marine royalty — blue whales," wrote the Santa Cruz Sentinel. To borrow a line from Melville: Surely all this is not without meaning.
And meaning there is in this tale of Pacific ecology and American history. The increased activity of marine megafauna is being attributed to an anchovy boom: The tiny fish have crowded the coast, densely packed, like so many slivers of silver in schools miles across and fathoms deep, sparking an ongoing feeding frenzy. The flip side of the great anchovy upwelling, though, is the great sardine crash of 2013, which scientists expect to reverberate throughout the ecosystem for decades to come. Cetaceans, sea lions, and pelicans in Monterey may be feasting on anchovies now, but they'll eventually be hurt by sardine scarcity, according to some biologists. An epidemic of sick sea lion pups in Southern California is already being blamed on the decline of sardines.
The last time Pacific sardines declined this steeply was around 1950, shortly after John Steinbeck so exquisitely captured the heyday of the sardine canning industry in his novel Cannery Row.
Atlantic editor Corby Kummer described the fishery's oscillation, and its significance, in a 2007 article titled "The Rise of the Sardine." In the decades before Steinbeck wrote his novel, the sardine industry was feeding millions of soldiers in both world wars and sustaining thousands of foreign-born workers—the canners and fishermen of Cannery Row—during the Great Depression. But the largest fishery in the Western hemisphere began to mysteriously decline even while it was being immortalized in literature. By the mid-1950s, it had collapsed entirely.
The canneries shut down and Monterey started losing its smell. From 1967 to 1986 there were severe restrictions on sardine fishing, and Cannery Row "turned into Skid Row," in Kummer's words. Then it went to the tourists: an abandoned cannery was transformed into the Monterey Bay Aquarium, a bronze bust of Steinbeck went up a few blocks away; now "Historic Cannery Row is Monterey's premiere destination for great hotels, shopping, dining, family fun and nightlife."
The sardines came back after a couple of decades, and the stock climbed steadily into the new millennium—hence Kummer's argument, in 2007, that sardines were ready for a culinary revival. But now the population has crashed again.
In the 1950s, the collapse of the sardine industry was blamed on overfishing. It's tempting to blame the current decline on global warming. Neither of those factors deserve single-handed responsibility, though. Oceanographers have known for a little while, now, that there's a natural ocean cycle—albeit, a long one that's not fully understood—that governs the rise and fall of sardine and anchovy stocks in the Pacific.
In 2003, scientists at the Monterey Bay Aquarium Research Institute (MBARI) combed through decades of data on physical oceanography, marine biology, and meteorology in the Pacific Ocean in search of longterm cycles governing sardine and anchovy populations. They concluded that sardine and anchovy stocks fluctuate according to a roughly 50-year "boom-and-bust" cycle. "A naturally occurring climate pattern that works its way across the Pacific," also known as the Pacific Decadal Oscillation, brings warmer temperatures to the California coast approximately every 25 years, prompting a switch-off between anchovies and sardines.
These findings implied that a sardine crash has less to do with overfishing than natural environmental patterns. But to say that overfishing has nothing to do with it, or that it's a completely natural phenomenon, would be an egregious oversimplification.