Environmental effects of purchasing, consuming mislabeled fish
Arizona State University
Perhaps that sauteed snapper you enjoyed last evening at your neighborhood restaurant was not snapper at all. Perhaps it was Pacific Ocean perch, cloaked in a wine sauce to disguise its true identity. The same goes for that grouper you paid a handsome price for at your local fishmonger's and cooked up at home. Instead, you may have been feasting on a plateful of whitefin weakfish and been none the wiser.
Seafood is the world's most highly traded food commodity, and reports of seafood mislabeling have increased over the past decade. However, proof of the environmental effects of mislabeled seafood has been scant as has research.
So, Arizona State University
researcher Kailin Kroetz and her colleagues analyzed the impact of seafood
mislabeling on marine population health, fishery management effectiveness, and
habitats and ecosystems in the United States, the world's largest seafood
importer.
The results of the
study were published in the Proceedings of the National Academy of
Sciences.
The study found that approximately 190,000 to 250,000 tons of mislabeled seafood are sold in the United States each year, or 3.4% to 4.3% of consumed seafood. What's more, the substituted seafood was 28% more likely to be imported from other countries, which may have weaker environmental laws than the United States.
"In the United
States, we're actually very good at managing our fisheries," said Kroetz,
assistant professor in ASU's School of Sustainability. "We assess the
stock so we know what's out there. We set a catch limit. We have strong
monitoring and enforcement capabilities to support fishers adhering to the
limit. But many countries we import from do not have the same management
capacity."
The authors used the
Monterey Bay Aquarium Seafood Watch scores for wild-caught product pairs to
assess marine population health and fishery management effectiveness.
"Although we
would like to do a global assessment in the longer run, we focused on the U.S.
first because Seafood Watch assesses about 85% of U.S. seafood consumed,"
Kroetz explained. "The data we were able to access in the U.S. were much
more detailed than what we could access on the global scale."
The study found that
substitute species came from fisheries that performed worse in terms of
population impacts 86% of the time. The population impact metric accounted for
fish abundance, fishing mortality, bycatch and discards -- that is, fish thrown
back to sea after being caught. In addition, 78% of the time the substituted
seafood fared worse than the expected products listed on the label when it came
to fishery management effectiveness.
Prior studies have
focused on the rates at which specific seafood is mislabeled. But it's the
quantity of substituted fish consumed that is key to determining environmental
impacts.
"The rates
themselves don't tell us the full story about the impact of mislabeling,"
Kroetz said. That's because some fish that have high rates of substitution have
low levels of consumption and vice versa. In fact, the majority of pairs have
relatively low rates of substitution and low consumption.
Good examples are
shrimp and snapper. The researchers found that giant tiger prawns are
substituted for white leg shrimp more than any other seafood product -- and
Americans eat more shrimp than any other type of seafood, opening the door to
potentially substantial environmental impacts. Meanwhile, snapper has a higher
rate of mislabeling, but Americans consume much less of it than shrimp.
At the very minimum,
mislabeling fish undermines good population management, and in turn,
sustainable fisheries.
Mislabeling can shake
consumer confidence in their quest to eat only sustainable, local seafood.
That's because substituted fish is more likely to be imported and come from
poorly managed fisheries, thereby creating a market for fish that shouldn't be
liberally consumed.
For example, you might
think you're getting this wonderful local blue crab, supporting local
fisheries, and experiencing local cuisine, but in reality, you could be eating
something that was imported from Indonesia. Learning about mislabeling might
reduce the amount you'd pay for blue crab in the future or result in you not
consuming it at all.
"The expected
species is often really well managed," Kroetz said. "Consuming fish
from a fishery shouldn't have a negative impact in terms of the population now
or in the future if the management is good. But if you're consuming fish from
poorly managed fisheries, that's not sustainable."
This study was funded
by the Paul M. Angell Family Foundation and Resources for the Future. The work
was also supported by the National Socio-Environmental Synthesis Center under
funding received from the U.S. National Science Foundation.