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There’s something fishy about that pet food…

Written by Atiya Henry (Commissioning Editor)

If you look at a label for pet food ingredients, you may see vague terms such as “ocean fish,” “white fish,” and “white bait.” But what exactly are these ingredients?

A team from Yale-NUS College (Singapore) has used DNA barcoding technology to analyze different pet food products. They revealed that pet foods purchased in Singapore may contain endangered shark species.

The authors, Ben Wainwright and Ian French, sought to build on a previous study conducted in the US in 2019, which detected shark in 78 pet food samples. In the current study, the team used DNA barcoding to analyze 45 different pet food products from 16 different brands in Singapore. They found that 31% of the 144 samples contained shark.

The blue shark (Prionace glauca) was the most identified shark, followed by the silky shark (Carcharhinus falciformis), and the whitetip reef shark (Triaenodon obesus).


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Importantly, both the silky shark and the whitetip reef shark are classed as ‘vulnerable’ on the International Union for Conservation of Nature Red List. In addition, the silky shark is also listed in the Convention on International Trade in Endangered Species of Wild Fauna and Flora Appendix II, to protect it against overconsumption incompatible with its survival.

Sharks play a crucial role at the top of the oceanic food chain and the dwindling number of sharks has caused instability in marine ecosystems. These latest results highlight the pressure placed on sharks by manmade factors, such as the shark fin and meat trade.

Contributing further to shark decline, other everyday products, such as cosmetics, may use shark-derived squalene as opposed to plant-derived squalene.

“Shark populations are overfished throughout the world, with declines of more than 70% in the last 50 years documented. This is indicative of the current lack of regard in which we hold our oceans,” observed Wainwright and French.

To maintain the survival of sharks, careful resource use and the reduction of unsustainable fishing are vital. Along these lines, the authors urge the need for global standards for pet food labels, and the use of clearer ingredient terms to allow pet owners to make more informed choices.

“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,” the authors concluded.