Article: Warner, Kimberly, Beth Lowell, Carlos Disla, Kate Ortenzi, Jacqueline Savitz, and Michael Hirshfield. “Oceana Reveals Mislabeling of Iconic Chesapeake Blue Crab.” (2015). Oceana (**see disclaimer below**)
Locally Caught Maryland Crab Cakes for Sale!
I currently live on the Eastern Shore of Maryland. Every day, I pass at least three “Maryland Crab Cakes!” and “Best Stop You’ll Ever Make!” type of seafood huts. It is clear that blue crabs are not only a foundation of the fishery business but also the ultimate Maryland icon. Blue crabs give Maryland residents, and local restaurants, a sense of identity. In fact, you could argue that there is nothing more Chesapeake than ordering a locally caught crab cake.
Blue crabs, a type of Atlantic swimming crab found from Nova Scotia to Argentina, have declined in Chesapeake Bay due to many causes including harsh winters, habitat loss, and over-fishing. This decline has caused some businesses to import blue crabs from non-Chesapeake regions and even import other swimming crab species from Indonesia. So, many restaurants proudly boast “Locally caught blue crab” to ensure you—the consumer—are getting the true Maryland experience.
Another bonus of getting a locally caught blue crab: it was very likely caught sustainably! The Monterey Bay Aquarium Seafood Watch has classified crabs caught by a crab pot as “good alternative” and trotline as “best choice.” These are the two most common crabbing practices in Chesapeake Bay. However, crabs caught in regions like South America and the Indo-Pacific can be caught unsustainably and even illegally by “pirate fishing”.
Herein lies the premise for this study: are these locally caught blue crab cakes actually made from blue crabs caught in our backyards? Oceana set out to discover: What is in your crab cake?
The approach: DNA testing crab cakes
Throughout the 2014 crab cake season (April to September), Oceana purchased 90 crab cakes from 86 establishments throughout Maryland and Washington D.C. (Table 1).
Unfortunately, these researchers did not get to eat the crab cakes, instead they sent them out to a lab for a DNA investigation. The DNA testing can detect whether a blue crab was (or was not) the crab ingredient in each sample. However, this test could not detect where that crab came from. Therefore, this study could not differentiate a locally caught blue crab from a blue crab caught outside of Chesapeake Bay.
Under the FDA guidelines, only Callinectes sapidus can be labeled as blue crab. Thus, if a menu claimed “blue crab” as the ingredient, and the DNA test uncovered it was not Callinectes sapidus, the crab cake was considered mislabeled.
What did they find?
The DNA test revealed that 34 out of the 90 crab cakes, or 38%, where mislabeled according to FDA guidelines (Figure 3). These crab cakes were sold as blue crab but were made from a different species of swimming crab. The regions with the highest percent of mislabeled crab cakes were Annapolis (47%) and Baltimore (46%); loosely speaking, if you bought a locally caught crab cake in Annapolis in 2014, there was a 50/50 chance you ate a crab species not from the Chesapeake.
The most common crab species “substituted” for blue crab was Portunus pelagicus, a blue crab species from the Indo-Pacific (Figure 4). In total, there were 8 crab species other than Maryland blue crab detected by the DNA analysis….and 3 of those species were not even listed by the FDA!
Oceana hypothesized that the Portunus crab species were most likely mislabeled as blue crab before they were imported to the United States. “Locally caught” blue crab sells for more money than imported crab; in 2014, a non-Maryland crab cake sold for ~$16.21 while a Maryland blue crab cake was pricier at $18.33. This means that restaurants with mislabeled crab cakes, whether they know it or not, upcharged their product.
Seafood fraud and mislabeling hurts the casual diner hoping for a Maryland experience. These practices inflate crab cake prices and can cheapen the “locally caught” advertisement. Additionally, crab fishing outside of the United States often involves unsustainable methods that could have negative ecological effects. This report uncovered that the United States imported some Callinectes spp. from Asian countries where this crab species does not even live, which seems fishy.
Are you surprised that 38% of Maryland crab cakes were mislabeled? How does that affect your thoughts on locally caught crab cakes?
Disclaimer: reports versus peer-reviewed articles
When reading a science article, a reader must know what kind of article they are reading. There are many types of science reports, from peer-reviewed journal articles to stories in magazines like National Geographic to white paper reports from non-profit groups like Oceana.
In science, peer-reviewed articles are often held in the highest regard since these papers undergo an intense critical review from third party experts in that field. Anything published in a peer-reviewed journal (such as Nature) has been rigorously scrutinized before acceptance for publication. In other words, there should be little bias or misleading information in that manuscript, otherwise it would have been rejected.
With that said, the Oceana report summarized above is not a peer reviewed-report. So one must pay careful attention to the methods used and how and why they came to each conclusion. However, reports are increasingly more common in science (most NOAA findings are internally reviewed reports) and do provide cutting edge and important findings!