This month, I ventured to ask the man behind the counter at a Whole Foods Market what kind of shrimp he was selling. "I don't know," he replied. "I think they're just normal shrimp." I glanced at the sustainable seafood guide on my phone. There were 80 entries for shrimp, none of them listed "normal."What about the cod? Was it Atlantic or Pacific? Atlantic. How was it caught? I asked. "I'm not sure," he said, looking doubtfully at a creamy fish slab. "With nets, I think. Not with harpoons."The shrimp had a blue sticker shaped like a fish on it, which appeared to be some type of official approval. Plus, they were on sale. I bought half a pound.I was using the Monterey Bay Aquarium's Seafood Watch app, one of a handful of sustainable seafood guides which base their recommendations of sustainable seafood on a range of factors, including where the fish came from, how it was caught or farmed and how the local environment was affected. Spend an hour trying to make sense of these guides, and you may feel more confused than when you started — and guilty about putting an unsuspecting grocery employee on the spot.These conundrums extend to restaurants as well. "The guide may tell you which species or fishing region is safest to eat, but if the restaurant menu just says, 'salmon,' you have to send someone to the kitchen to ask," says Alena Van Arendonk, an animal trainer in Indianapolis, who tries to use Seafood Watch to find environmentally friendly seafood that is not overfished. "Often [restaurants] don't know where the fish came from."And even if you do find out where the fish came from, you might get conflicting advice from two different guides: Are summer flounder populations improving or is it irresponsible to eat the fish? A consumer is often left to puzzle over which advice to follow.After years of feeling overwhelmed trying to pick the right seafood, I finally decided to find out why and how sustainable seafood guides vary, and how customers might sort through them to make the most environmentally friendly choices.All reputable seafood guides are based on science. Take these three for example – Seafood Watch, the Safina Center at Stony Brook University's seafood ratings guide, and the Environmental Defense Fund's Seafood Selector. All three use scientific data from the Monterey Bay Aquarium, which relies on a team of more than 20 scientists who weigh factors like fish population, harm to habitat, harm to other species, and management practices to determine the sustainability of a fishery. These factors produce ratings of green (best), yellow (good alternative), or red (avoid). Despite this shared source of data, the guides offer similar but different advice.Take, for example, Atlantic cod, a poster-fish for the woes of historical overfishing. The Monterey Bay Aquarium labels only farmed cod as a "best choice." But cod caught by handline in the U.S. Georges Bank and the U.S. Gulf of Maine are good alternatives. The 11 other permutations of geography and fishing method are all off the table. The Safina Center, on the other hand, splits the fish into three groups, makes no reference to farmed cod, and calls handline methods anywhere in the U.S. a good alternative. As for EDF, it refers to all Atlantic cod with a special indicator called "improving."So, what gives?"A personal take I've learned along the way," says Shelley Dearhart, the program director for sustainable seafood at the Safina Center, "is that for sustainable fisheries, so much of it comes down to personal values."That personal value for EDF is "fishery reform," says Timothy Fitzgerald, the fund's Director of Impact. The Monterey Bay Aquarium is more of an independent assessor, he says. "Whereas we are much more advocates trying to improve fisheries." That means that if a fishing group is collaborating with EDF to make its methods more sustainable, EDF will label the seafood as "improving," to avoid blacklisting fishers making a good faith effort to change."Atlantic cod are an iconic example of this caveat," says Fitzgerald. Atlantic cod populations are so small and quotas so low that no fisher can focus solely on cod to earn a living, so they catch other "groundfish" as well: fish with white, flaky meat like pollock and haddock. These fisheries have moved away from seasons limited by the number of days — a traditional practice that encouraged intensive overfishing in a short period of time — to a system that designates the amount of fish different fishers can catch. EDF considers the change a move toward sustainability, hence the "improving" rating. So if you buy Atlantic cod from say Gulf of Maine fishers, you help support more environmentally conscious fishing practices. (EDF also promotes more environmentally conscious fishers through a separate campaign called Eat These Fish, which encourages people to eat some lesser known, but plentiful fish species caught locally off U.S. shores, like West Coast rockfish.)The Monterey Bay Aquarium on the other hand, is more present-minded, according to Ryan Bigelow, who manages program engagement for Seafood Watch. "Our recommendation is a snapshot in time," he says. Because cod populations are still low, only cod farming gets the nod of approval.The Safina Center takes a similar approach, but focuses on fishing, rather than farming, according to Dearhart. The center's suggestions follow Monterey Bay's, but lack references to farmed cod (so there's no "best" Atlantic cod option in Safina Center ratings).Why the varying levels of detail? "I don't want to say we offer a simplified message, but we want to break it down, because fisheries are so ridiculously complicated," says Dearhart of the Safina Center's approach, which consists of a color rating and information bullet point for each fish. Seafood Watch is more detailed, Bigelow says, because detail is necessary to partner with large-scale retailers like super markets and restaurants, which must make big decisions about sourcing shrimp, cod, and everything in between. In the interest of transparency, the guide puts all of its information in the guide.Which guide is best for a user, these experts say, depends on value judgments, like whether changes auguring future improvements are enough reason to support a fishery. Consumers might also care about factors not considered by any of the guides, like the carbon footprint of transporting seafood to their area. These consumers might opt to eat more local seafood.The experts I talked to admitted it can be difficult for consumers to get enough information from businesses about their seafood to make a good choice. That's one of the reasons Seafood Watch has added a feature that allows users to locate its business partners, so one can know seafood is sustainable without asking questions. For example, Safina Center and Seafood Watch work with Whole Foods to avoid unsustainable seafood. That's good news for my shrimp.If you're like me, though, you can't afford Whole Foods for most of your shopping. In this case, the experts say it's best to overcome fears of being "that person" and just ask whether a business's seafood is sustainable. If the person behind the counter doesn't know, then at least you've shown demand for more information.Or, one could take the approach of wine specialist Andrew Dunaway of Jackson, Miss. He calls Seafood Watch a Pandora's Box because so few of the restaurants in his area meet the guide's sustainability standards. But Dunaway hasn't dismissed the guide completely – he just found a way to make it work for his purposes, by familiarizing himself with information about a couple types of seafood he eats frequently and by relying on domestic sources."It's ingrained in the mentality in this part of the country to eat only Louisiana crawfish. So there's never any worry about the poorly raised Chinese crawfish that are in the freezer case," says Dunaway. The same goes for local catfish, a family favorite. "American farm-raised catfish is a good source," he says. "I've only had to check the guide once to see that."
Natalie Jacewicz is a science writer living in New York City.
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