April 1, 2012 – The smallest fish in the sea are more than twice as valuable when they’re eaten by bigger fish than when they’re caught by humans, according to a report released Sunday by a scientific task force.
The 120-page analysis by the Lenfest Forage Fish Task Force — a group of 13 scientists specializing in everything from fish ecology to marine mammals and seabirds — underscores the growing concern researchers have about the fate of forage fish, including anchovies, mehaden, herring and sardines that serve as food for bigger fish, sea birds and marine mammals.
Forage fish account for 37 percent of the world’s commercial fish catch, with an annual value of $5.6 billion. (Only 10 percent of forage fish caught are eaten by humans; the remaining 90 percent are processed into fish meal and fish oil, which feed livestock and farmed fish.)
But the team of scientists, who worked for three years on their analysis, concluded that forage fish support $11.3 billion worth of commercial fish by serving as their prey. In the North Sea, for example, sand eels help sustain cod, and tuna in the eastern tropical Pacific Ocean feed on sardines.
The issue has become increasingly important for fishery managers in the mid-Atlantic, who voted in November to cut the amount of menhaden that can be harvested annually from 183,000 metric tons to 174,000, out of concern that the fish have been depleted.
One company, Omega Protein, took 160,000 metric tons of menhaden — 80 percent of about 450 million fish harvested in 2010 — off the coast of Virginia, which is the only state that allows industrial fishing of menhaden.
Edward D. Houde, a task force member and a professor at the University of Maryland’s Center for Environmental Science at the Chesapeake Biological Laboratory, said the task force concluded that fishery managers should leave at least 40 percent of adult forage fish in the sea. Menhaden support a range of species in the Chesapeake Bay and Atlantic Ocean, including striped bass, osprey, bald eagles and brown pelicans.
Read the full article at the Washington Post.
Analysis: The Task Force recommends signifcant reductions in commercial harvesting for forage fish. It argues that such reductions are necessary to avoid "pull[ing] the rug out from under the ecosystem." However, the the available evidence on one of the forage fish mentioned, Atlantic menhaden, suggests that reducing the commercial harvest might not significantly impact the growth of the menhaden population.
In its 2010 stock assessment, the Atlantic States Marine Fisheries Commission (ASMFC) wrote, “past performance of the Atlantic menhaden suggests it has gone from periods of low recruitment [the number of menhaden that spawn] and fecundity [the number of eggs produced by the stock] to periods with high recruitment and fecundity, while sustaining moderate to high landings.” It further notes that recent landings that are low by historical standards do not seem to correlate with recruitment levels. It concludes that these trends may indicate that fluctuations in the menhaden population may be “almost entirely driven by non-fishery sources.”
In addition to evidence that suggests reducing the commercial menhaden catch may not be an efficient way to increase stock size, there is also evidence that providing adaquete forage for predatory fish and birds might not currently be as large of a concern in the Chesapeke Bay area. As mentioned in the Lenfest report, the Chesapeake has seen its striped bass population, as well as the populations of piscivorous birds like ospreys have rebounded in recent years. Since all of these species feed on menhaden, among several other species of fish, there recovery does not suggest a lack of forage.