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Your cat or dog couldn't beat a shark in a fight, but they're still a threat to the sharp-toothed marine predators.
According to recent research, several brands of pet food contain shark, but label the ingredients simply as "ocean fish," or something similar. Consumers don't know it, and many undoubtedly wouldn't like it, especially considering that the global abundance of sharks has declined by 70% in the past 50 years.
“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 researchers Ben Wainwright and Ian French of Singapore's Yale-NUS College, who oversaw the study that arrived at these unsettling results.
In an evaluation of 45 pet food products from 16 different brands, 144 samples were sequenced. The researchers found that approximately one-third of the samples contained shark DNA, including some species listed as "vulnerable" on the International Union for Conservation of Nature (IUCN) Red List, such as the silky shark and the whitetip reef shark. One ecologist explained that a lack of strict labeling makes it easy for pet food manufacturers to include pretty much any type of ocean fish in their products, without regard for international regulations.
- Sharks are made of cartilaginous tissues, which means they don't have bones.
- Scientists estimate that sharks have existed for about 455 million years.
- The world's biggest fish is the whale shark, which can weigh 40 tons and reach 40 feet (12.2 m) in length.