Supermarket Science: How Consumer Choices Could Affect Ocean Biodiversity

Image Credit: AntTree, CC-BY-NC-ND 2.0
Can you help ease the global biodiversity crisis through the choices you make at your local fish market? A recent report by US-based nonprofit Eating with the Ecosystem suggests that the answer is a resounding “Yes!”
By now, you may have heard all about the recent UN report on biodiversity, a massive international effort which concluded that one million species worldwide are threatened with extinction. This is alarming news; humanity depends on biodiversity in countless ways, from energy production to security from severe weather to the food that we eat. Consider the fishing industry: the UN estimates that 17% of the world relies on fish as a primary protein source and that one in ten people worldwide depend on fisheries for their livelihood. Given the importance of fisheries, it’s critical that the global fishing industry manages the world’s marine resources in a sustainable way, which requires preservation of the intricate food webs and ecological connections in our oceans.
Are there really always more fish in the sea?
Commercial fishing is extensively regulated to ensure that fish populations can sustain themselves into the future. But even with the best available data, management mistakes have been made—and these mistakes are often devastating. In the early 1990s, for example, the population of Atlantic cod off the coast of the northeastern United States and Canada fell to a mere 1% of its previous levels, devastating the regional fishing industry. More recently, a 2015 report indicated a decrease of 74% in important food fishes such as mackerel and tuna between 1970 and 2010.
Fisheries crashes are damaging for many reasons. First, there are negative ecological impacts of nearly eliminating a major component of the marine food chain. Fisheries crashes don’t just harm the species targeted by commercial fishing; they have ripple effects that can destabilize the entire marine ecosystem, making recovery a slow, tenuous process. Second, the loss of an important food source can have serious consequences for consumers that rely on fish as a protein source. And finally, fisheries crashes can spell economic disaster for the fishing industry, which is often heavily reliant on a small number of species.
While the challenge of making commercial fisheries sustainable is complex, there is one clear action that can be taken immediately: bring the diversity of the open ocean into the market! Currently, most commercial fisheries are highly selective for a small number of popular fish species, due in large part to consumer preferences. This “all eggs in one basket” approach leaves both the ecosystem and the fishing industry at risk. A better approach would be to distribute the fishing pressure among a more diverse selection of species, making food sources and fishing economies more resilient.

Science in the supermarket
This leaves us with a big question: how to convince consumers—you and me!—to buy, cook, and eat a much wider variety of fish? The selectivity of the commercial fishing industry, remember, is driven by consumer demand; if consumers show that they are willing to purchase a more diverse selection of fish, then an industry and market will more than likely follow.
Recently, scientists at Eating with the Ecosystem got creative with some ecological research methods for tackling this issue. They started out by comparing the fish species present along the coast of New England, USA, with the species found in New England grocery stores. To do this they used the Shannon-Wiener Diversity Index, a common way of measuring biodiversity in an ecosystem. In this case, the ecosystem of interest was a selection of local grocery stores.
They found that only five of 52 fish species that are common in the waters off the New England coast could be found in local grocery stores with any regularity: these species were available at least 50% of the time that consumers visited a store to look for them. In contrast, 20 of the 52 species were nearly impossible to find in the market: these 20 fish were found on fewer than 5% of grocery trips! Unsurprisingly, market diversity was a bit higher closer to the coastline than it was farther inland, but the difference was small. The main conclusion was that fish markets offer a pretty disappointing selection of fish when compared with the natural diversity just off the coast.

Voting with your dollar (and dinner plate!)
Eating with the Ecosystem didn’t stop at describing the problem, though. They carried on with their research to try and find some solutions. For six months, they engaged 86 community scientists in a weekly research mission entitled Eat Like a Fish. Each week, volunteers were randomly assigned a set of fish species to track through the entire consumer process—shopping, purchasing, cooking, and eating. Eating with the Ecosystem compiled data on barriers that might be stopping consumers from seeking out—and creating market demand—for more unusual species.
They found that simple adjustments can make a big difference in consumers’ willingness to try a new fish species. For example, fish sellers could display recipes near more unusual products, grocery stores could offer brief cooking demonstrations, and fishmongers could put up information making it clear to consumers that they’re happy to engage in conversations about their products. Once consumers got over any initial hesitation, most of them were pleased with their purchase of a new species and reported that they’d happily buy it again.
Are you starting to feel the urge to visit your grocery store and check out their fish counter for a new-to-you species? Go for it! Eating with the Ecosystem’s main advice to you is to not be afraid. Ask your fishmonger for recipe advice, google the species name, and enjoy the experience of trying something new. If enough of us follow this advice, we can make a real difference in supporting more resilient ecosystems and fisheries—not to mention, we’ll eat some delicious seafood in the process.
Want to learn more? You can read the whole Eat Like a Fish report here.