DNA From Endangered Sharks Found in Cat and Dog Food

Vague labeling results in people unwittingly serving their pets vulnerable species.

Sand tiger sharks are among the vulnerable species whose DNA was found in pet food.Stefan Sauer/Zuma Press

This story was originally published by the Guardian and is reproduced here as part of the Climate Desk collaboration.

Pet food containing endangered sharks is being fed to cats and dogs by unwitting owners, a study has revealed.

Scientists found that several brands contained endangered species but listed only vague ingredients such as “ocean fish,” meaning that consumers are often oblivious.

“The majority of pet owners are likely lovers of nature, and we think most would be alarmed to discover that they could be unknowingly contributing to the overfishing of shark populations,” said the study authors, Ben Wainwright and Ian French, of Yale-NUS College, Singapore.

Shark populations are overfished throughout the world, with declines of more than 70 percent in the past 50 years. As apex predators they are crucial for the balance of the ocean food chain, and the loss of sharks has had knock-on effects on seagrass beds and coral reefs.

The sale of shark fins has been widely publicized. But a silent contributor, the authors say, is the use of shark products in everyday items such as pet food and cosmetics.

Using DNA barcoding, the scientists tested 45 pet food products from 16 brands in Singapore. Most products used generic terms such as “fish,” “ocean fish,” “white bait,” or “white fish” in the ingredients list to describe their contents, with some specifically listing tuna or salmon. Others did not indicate fish at all.

Of the 144 samples sequenced, 45—roughly one-third—contained shark DNA. The most frequently identified species were blue shark, silky shark, and whitetip reef shark. The silky shark and the whitetip reef shark are listed as “vulnerable” in the International Union for Conservation of Nature (IUCN) Red List.

Products containing DNA of the sicklefin weasel shark, the Caribbean sharpnose shark, and the sand tiger shark—all vulnerable species—were also identified.

The authors suggest the meat could be taken from shark carcasses that would be discarded after the valuable fins are removed, or could reflect a growing shark meat trade. They are calling for more accurate ingredients labelling so that people know what they are feeding to their pets and where it came from.

Dr Andrew Griffiths, an ecologist at the University of Exeter, said the latest work followed research by his team and others revealing the presence of shark DNA in food products for human consumption, including the sale of spiny dogfish and hammerhead shark meat in fish and chip shops.

For pet foods, he said, the lack of rules on specific labelling meant a wide variety of vulnerable species could be legally included. “There aren’t any specific rules against it,” he said. “You could be unwittingly getting just about any fish.”

Besides the lucrative trade in shark fins, shark meat is generally quite low value, Griffiths said, and could be a cheap source of protein. “Lots of people don’t want to eat it,” he said. “So you can’t necessarily sell it through other supply chains. It surprises people that these things can turn up on their pet’s plate.”

The findings are published in the journal Frontiers in Marine Science.

More Mother Jones reporting on Climate Desk

WE'LL BE BLUNT.

We have a considerable $390,000 gap in our online fundraising budget that we have to close by June 30. There is no wiggle room, we've already cut everything we can, and we urgently need more readers to pitch in—especially from this specific blurb you're reading right now.

We'll also be quite transparent and level-headed with you about this.

In "News Never Pays," our fearless CEO, Monika Bauerlein, connects the dots on several concerning media trends that, taken together, expose the fallacy behind the tragic state of journalism right now: That the marketplace will take care of providing the free and independent press citizens in a democracy need, and the Next New Thing to invest millions in will fix the problem. Bottom line: Journalism that serves the people needs the support of the people. That's the Next New Thing.

And it's what MoJo and our community of readers have been doing for 47 years now.

But staying afloat is harder than ever.

In "This Is Not a Crisis. It's The New Normal," we explain, as matter-of-factly as we can, what exactly our finances look like, why this moment is particularly urgent, and how we can best communicate that without screaming OMG PLEASE HELP over and over. We also touch on our history and how our nonprofit model makes Mother Jones different than most of the news out there: Letting us go deep, focus on underreported beats, and bring unique perspectives to the day's news.

You're here for reporting like that, not fundraising, but one cannot exist without the other, and it's vitally important that we hit our intimidating $390,000 number in online donations by June 30.

And we hope you might consider pitching in before moving on to whatever it is you're about to do next. It's going to be a nail-biter, and we really need to see donations from this specific ask coming in strong if we're going to get there.

payment methods

WE'LL BE BLUNT.

We have a considerable $390,000 gap in our online fundraising budget that we have to close by June 30. There is no wiggle room, we've already cut everything we can, and we urgently need more readers to pitch in—especially from this specific blurb you're reading right now.

We'll also be quite transparent and level-headed with you about this.

In "News Never Pays," our fearless CEO, Monika Bauerlein, connects the dots on several concerning media trends that, taken together, expose the fallacy behind the tragic state of journalism right now: That the marketplace will take care of providing the free and independent press citizens in a democracy need, and the Next New Thing to invest millions in will fix the problem. Bottom line: Journalism that serves the people needs the support of the people. That's the Next New Thing.

And it's what MoJo and our community of readers have been doing for 47 years now.

But staying afloat is harder than ever.

In "This Is Not a Crisis. It's The New Normal," we explain, as matter-of-factly as we can, what exactly our finances look like, why this moment is particularly urgent, and how we can best communicate that without screaming OMG PLEASE HELP over and over. We also touch on our history and how our nonprofit model makes Mother Jones different than most of the news out there: Letting us go deep, focus on underreported beats, and bring unique perspectives to the day's news.

You're here for reporting like that, not fundraising, but one cannot exist without the other, and it's vitally important that we hit our intimidating $390,000 number in online donations by June 30.

And we hope you might consider pitching in before moving on to whatever it is you're about to do next. It's going to be a nail-biter, and we really need to see donations from this specific ask coming in strong if we're going to get there.

payment methods

We Recommend

Latest

Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate