In recent weeks, sardines have been a hot news topic again. Environmental groups like Oceana complain that the sardine population is collapsing just like it did in the mid-1940s. They blame “overfishing” as the reason and maintain that the fishery should be shut down completely.
Today, in truth, Pacific sardines are perhaps the best-managed fishery in the world — the poster fish for effective ecosystem-based management. The current harvest control rule — established in 2000 and updated last year with more accurate science — sets a strict harvest guideline that considers ocean conditions and automatically reduces the catch limit as the biomass declines.
If the temperature is cold — which hampers sardine recruitment — the harvest rate is low. And if the population size decreases, both the harvest rate and the allowable catch automatically decrease.
Current management sets aside a 150,000 metric ton reserve off the top of the stock assessment and automatically closes the directed fishery when the biomass estimate falls below that level, which it did in the latest stock assessment, after four years of abnormally cold La Niña ocean conditions.
In fact, the truth is much more complicated than environmentalists would lead you to believe. It’s inaccurate and disingenuous to compare today’s fishery management with the historic sardine fishery collapse that devastated Monterey’s Cannery Row.
In the 1940s and ‘50s, the fishery harvest averaged more than 43 percent of the standing sardine stock. Plus, there was little regulatory oversight and no limit on the annual catch.
Today, based on the latest stock assessment, the U.S. exploitation rate has averaged about 11 percent, ranging as low as 6 percent, since the return of federal management in 2000.
Here’s where complications begin because scientists recognize two stocks on the West Coast: the northern or “cold” stock ranges from northern Baja California to Canada during warm-water oceanic cycles and retracts during cold-water cycles.
A southern or “temperate” stock ranges from southern Baja to San Pedro, in Southern California. The federal Pacific Fishery Management Council manages only the northern stock.
Doing the math, our current fishery harvest is less than one-quarter of the rate observed during the historical sardine collapse.
In fact, the current sardine harvest rule is actually more precautionary than the original rule it replaced. It does this by producing an average long-term population size at 75 percent of the unfished size, leaving even more fish in the water, vs. 67 percent in the original rule. The original harvest rule reduced the minimum harvest rate to 5 percent during cold periods. The present has a minimum rate of 0 percent during cold periods.
The so-called “sardine crash due to overfishing” mantra now peddled by Oceana isn’t anything of the sort. It’s simply natural fluctuations in biomass that follow the changing conditions of the ocean, reflected in part by sea temperature.
In April, the council will discuss the most recent sardine assessment report and decide on future management measures. It is important to understand that the sardine stock assessment is a conservative estimate based on acoustic surveys that miss sardines in the upper 10 meters of the water column, above the down-looking acoustic transducer, and in shallow near-shore waters where survey vessels cannot go. It’s really a question of scale, fishermen say. While they acknowledge sardines’ downward trend, fishermen question the accuracy of the total number of sardines that the stock assessment estimates.
California’s wetfish industry relies on a complex of coastal pelagic species including mackerels, anchovy and market squid as well as sardines. Sardines typically school with all these species, so a small allowance of sardine caught incidentally in these other fisheries will be necessary to keep wetfish boats fishing and processors’ doors open.
Sardines are critically important to California’s historic wetfish industry as well as the Golden State. This industry produces on average 80 percent of total fishery landings, and close to 40 percent of dockside value. A total prohibition on sardine landings could curtail the wetfish industry and seriously harm California’s fishing economy.
D.B. Pleschner is executive director of the California Wetfish Producers Association, a nonprofit dedicated to research and to promote sustainable wetfish resources.
Posted in http://www.montereyherald.com 04/04/15