Bigger isn't necessarily better when it comes to catching, selling and eating fish.
For certain snappers, in fact, a market preference for plate-size whole fillets is driving fishermen to target smaller fish. For some wild fish populations, this is a recipe for collapse.
"The preferred size of a fillet in the U.S. market corresponds to juvenile fish that haven't had a chance to reproduce," says conservation biologist Peter Mous, director of the Nature Conservancy's Indonesia Fisheries Conservation Program. "A lot of species here are heavily overfished, and this demand for small fillets is making things worse."
Of particular concern for conservationists are such species as Malabar snapper. Mous says this fish becomes sexually mature at four pounds and can grow as large as 29 pounds — but global restaurant and retail markets prefer to buy it at two pounds and as small as one pound.
"For a large species like giant ruby snapper, the differences are even more extreme," Mous wrote in an email. "The trade buys them at 1 lb., but they only become adults at 9 lbs., while [they] can grow to 73 lbs."
The Indonesian snapper fishery, which Mous has been studying since the late 1990s, focuses on numerous species in several genera. The reproductive patterns and growth rates of these fish vary widely, but with virtually all species, the market prefers what are essentially baby fish. He says many snapper species have already been depleted to an estimated 10 percent of their unfished biomass — a term that refers to a population's total mass, rather than the number of individuals.
Mous' organization is trying to change the industry by encouraging seafood buyers and exporters to commit to purchasing only fish greater than a certain minimum size. This would motivate fishermen to catch bigger snappers and leave the juveniles in the water, allowing the fish to eventually reproduce and help replenish their population.
The campaign is gaining some traction. Norpac Fisheries Export, which sells to Safeway, Costco and other companies, signed on to the campaign in January, and a few weeks later, Netuno USA, the largest importer of frozen snapper in the U.S., followed suit. Rachel Winters, associate director of media relations for the Nature Conservancy, says eight more distributors have since announced their commitment to the fishery plan, including five that made the pledge on Sunday, March 17, in Boston, on the first day of Seafood Expo North America.
The demand for smaller fish seems to be coming mainly from the American retail and restaurant market, where many chefs and large-scale caterers tend to prefer not only whole intact fillets, but fillets that, on their own, perfectly constitute a single portion.
"Chefs prefer fish where the fillet size is ready to serve," explains Christian Monchâtre, a Paris-born chef who has worked for more than 20 years at restaurants in Europe, Mexico and California. "It's cost-effective — you don't have extra scraps where you have to develop other recipes in order to use them." Monchâtre says chefs who wind up with larger-than-optimal fillets "lose money with every serving."
While whole fillets are a visually appealing and very popular serving style, so is a whole fish, says Andre Brugger, the sustainability compliance and quality assurance manager at Netuno USA.
"A lot of places serve a whole snapper, and to fit in on the plate and for it to serve two people, it can't be a huge fish," Brugger says.
Brugger says the demand for small and uniform fish fillets is strongest in situations in which a chef or restaurant is serving large numbers of people, as on cruise lines or in hotel restaurants.
"It's more efficient for them," he says.
Not everyone in the seafood industry sees this pattern. Kenny Belov, co-owner of, a San Francisco fish company, says most clients he works with — including large tech companies like Airbnb and SurveyMonkey — don't care if fillets must be cut into irregular pieces to create the perfect serving size.
"They'll say, 'We want 700 two-ounce portions,' " he says, noting that such a request will not "change the size of the fish I start with."
What's more, Belov says his buyers favor bigger fish. "I could show you a year's worth of restaurant orders, and on every one they specify they want the largest fish possible."
This, he explains, is because with many species of fish, the bigger each animal is, the more meat and fat it contains as a percentage of its total body weight. This makes it more profitable for him to buy the largest fish he can get from fishermen.
And Monchâtre notes that it can be just as cost-effective to process and serve very large fish as it is small fish. Large fillets can be readily cut into multiple hand-size portions that are more or less equal in size and quality, and the scrap meat from the belly and from the filleted carcasses may be sufficient to make into a batch of ceviche or poke. It's the midsize fish, he says — such as barely mature snapper — where chefs lose money.
But the discussion of what fish size is optimal and most sustainable can go the other way too. A paper published in the journal Sustainabilityin 2011 found that farmed channel catfish, rainbow trout and sablefish converted feed into body mass more efficiently when they were of younger age. The larger these fish got, the less efficiently they utilized feed, making it more profitable to sell them small, the authors, led by Michael Tlusty, reported.
This works out well for both fish farmers and buyers who want smaller fish. Monchâtre says farms that raise branzino in Greece, for example, make it "very easy to get fish of all the same size."
But where Monchâtre sees branzino farms as a solution for buyers interested in a uniformly sized product,, author of the book Four Fish, believes these farms could be helping to fuel the demand.
"What's the chicken, and what's the egg?" he says. "Because this uniform product is now presenting itself in aquaculture, it may be imposing those same demands on wild fisheries."
In his 2010 book, Greenberg wrote that "Greece sends nearly a hundred million of those exactly plate-size fish to diners throughout Europe, the United States, and beyond every single year."
Today, he says, branzino, also known as Mediterranean sea bass, remains a major export product from southern Europe and Turkey. Nearly all the fish are harvested at about a pound in weight, Greenberg says.
In addition to the ready availability of evenly sized fish from farms, Greenberg also suspects that changes in how and where Americans eat could be affecting how and what fishermen catch. Shifting "to a service economy rather than a cooking-at-home economy," he says — as well as the growing popularity of ready-to-cook meal kits — is likely creating a greater demand for ingredients of homogeneous size and shape, as chefs face the challenge of feeding more people as efficiently as possible.
Yukiko Krontira, marketing director for a Greek finfish farm called Kefalonia Fisheries, explained in an email that Mediterranean sea bass weighing between roughly 12 and 20 ounces "fall right into the consumer's comfort zone," while medium to large fish "do not have the same demand as portion sized fish."
While sustainable fish-farming operations may be able to meet the demand for portion-size fish and fillets, Belov says expecting such uniformity from wild populations will drive unsustainable fishing.
"If you want only fillets of a single size, there are very few fish that we consume globally that provide you with that option," he says, noting that salmon, halibut and tuna, among others, are too big to be eaten this way but are still valued.
Thomas Kraft, founder of Norpac Fisheries Export, says "standardization makes industries more cost-effective." But, he says, in the case of wild fish, breaking away from industry norms could be critical for sustaining the Indonesian snapper industry. Kraft expects that chefs, acting as role models and even celebrities, will be pivotal in changing the market and, eventually, motivating fishermen to try to catch more mature snappers.
"This needs to come down from the top," he says.
Brugger, of Netuno USA, sees the same path forward. Eventually, a shift in demand from chefs and retailers will reach the water level, and fishermen, he says, will respond.
"They'll go somewhere else to catch bigger fish," he says.
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