Feb 15 2011

Sardine collapse due to multiple causes

This commentary was originally published in the Monterey County Herald.

Guest commentary

On Jan. 30 The Herald published an excerpt, headlined “Overfishing triggered ruin of the sardine,” from a book by authors Steve Palumbi and Carolyn Sotka.

But there’s just one problem. The story is not entirely true.

“Ruin” is a harsh – and incorrect – headline to describe the storied sardine decline in the 1940s.   While the fish exodus may have ruined the canneries that once crowded Cannery Row, the sardines did return. And so has Monterey’s wetfish industry – so named because these species were canned ‘wet from the sea’ with little preprocessing.

In their column, Palumbi and Sotka actually allude to the fact that there is much more to the story than simple overfishing.  They note that, “Ed [Ricketts] also somehow knew that part of the problem was not overfishing, but a change in the ocean.”

In the 1960s, two decades after Ed Ricketts, scientists studying anaerobic sediments in the Santa Barbara Basin in Southern California discovered a natural historic record of pelagic fish populations, including sardine and anchovy.  These initial findings were the first step in proving Ed Ricketts’ earlier theories about ocean cycles.

In fact, analysis of the scale-deposition series showed that sardines and anchovies both tended to vary, layered in the deep mud, over a period of approximately 60 years, with the average time for sardine recovery about 30 years.

What’s more, the scale-deposition record counted nine major recoveries and subsequent collapses of the sardine population over a 1,700 year period.  Scientists Soutar, Isaacs, Baumgartner and others found the current recovery was not unlike those of the past in its rate or magnitude. Sardines were fated to decline with or without fishing pressure:  warm-water cycles favor sardines, and cold-water cycles favor anchovies.

Sardine recoveries and collapses

The sardine decline spurred the creation of the California Cooperative Fisheries Investigations (CalCOFI), a consortium composed of the National Marine Fisheries Service (NMFS), Scripps Institution of Oceanography and California Department of Fish and Game (DFG), whose focus was to study the sardine and other coastal pelagic species in the California Current System. California’s wetfish industry contributed funding and manpower to advance the research.

The DFG curtailed sardine harvest beginning in the late 1960s, and lifted the moratorium to allow a 1,000-ton harvest nearly 20 years later, after estimating a biomass of at least 20,000 tons.  The sardine resource expanded at an estimated 30 percent per year in the 1980s, stretching its boundaries from Southern California to the Pacific Northwest and Canada by the late 1990s.  New research and scientific models estimated the population at more than one million metric tons in 1999, when management authority transferred to the federal NMFS, which declared the population fully recovered.

Currently there’s a shift to a cold-water Pacific decadal oceanic cycle; the sardine population may again be entering another natural decline.  But now California’s sardine industry is limited to only 65 permitted vessels (63 active), restricted by a capacity goal and landing limits.   The sardine fishery is regulated under the federal Magnuson Act, with strict overfishing limits and annual catch limits to prevent overfishing.

The harvest control rule deducts 150,000 metric tons off the top of the biomass estimate (all fishing would be curtailed below that level) to provide forage for other marine life, as well as ensure a sustainable base population.  In addition, the allowed harvest rate is only 15 percent (net 10-11 percent after subtracting the 150,000 mt ‘cutoff’), far lower than other fishery exploitation rates.

Today the wetfish industry in Monterey is a traditional industry with a contemporary outlook.

Fishermen and markets actively engage in collaborative research on sardine and also market squid. The sons of the fathers and grandfathers before them who now harvest and process the wetfish complex– sardines, anchovies and market squid, all dynamic resources with natural cycles of abundance – still form the foundation of Monterey’s storied fishing community – culturally and economically.

These fishing families hope to carry on; and they should – wetfish resources are among the most sustainable marine life species in California, especially under today’s precautionary fishery management.

With 30 years of fishing industry experience, D.B. Pleschner is the executive director of the non-profit California Wetfish Producers Association, whose mission is to protect wetfish resources and the historic industry.  She’s a former contributing editor of Pacific Fishing magazine, and manager of the California Seafood Council.

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