Traces of endangered shark DNA have been found in pet food sold in Singapore, and referenced to several brands. This is the result of research conducted at Yale NUS College in Singapore and published in the journal Frontiers in Marine Science.
The research team analyzed 45 pet food products from 16 brands purchased in Singapore. For each sample, DNA was analyzed to understand which meat was really inside them. Out of 144 sequenced samples, 45 contained blue shark, silk shark, and white tip shark DNA.
Research authors said, "None of the products specifically listed shark as an ingredient, listing only generic terms, such as ocean fish, white fish, and white bait. The vague terminology used to describe pet food ingredients and, in some Incorrect content labeling prevents consumers, in this case pet owners, from making informed and environmentally friendly decisions.
As a result, pet owners and animal lovers may unknowingly contribute to fishing excessive use of endangered sharks. Shark populations have declined by more than 70% in the past 50 years, mostly due to fishing, three-quarters of all ocean shark species are at risk of extinction.
These declines were largely attributed to increased fishing efforts. Despite increased public awareness of shark conservation, three-quarters of all ocean shark species are currently considered endangered."
The blue shark is an oceanic and epipelagic shark found worldwide in temperate and tropical waters from the surface to depths of 350 meters.
In temperate seas they approach the coast where they can be observed by divers, while in tropical waters they inhabit deep waters. The range extends north to Norway and south to Chile. We therefore find them off the coast of all continents, except Antarctica.
In the Pacific Ocean, most inhabit the strip between the twentieth and fiftieth parallel north, even if there are seasonal shifts. In the tropical belt they are uniformly spread between the twentieth north parallel and the twentieth south parallel.
They prefer waters at temperatures between 7 and 16 ° C, but also tolerate temperatures above 21. Observations in the Atlantic have identified clockwise migratory cycles that follow the main currents. It was quite common to find them in the Mediterranean Sea, especially in the Adriatic Sea, but always far offshore, while today their number is decreasing.
It prefers colder temperatures, and can migrate across long distances, such as from New England to South America. Although they are generally lethargic animals, they can move very quickly when needed. They are livebearers and are known to give birth to more than 100 fry at a time.
They feed mainly on fish and squid, although they can catch larger prey. They often move in schools divided by size and sex. The maximum life span is unknown, but it is estimated that they can reach an age of around 20 years.