Scientists claim that they have identified the first known omnivorous shark species and 60 per cent of its diet consists of seagrass. These findings were published recently in the journal Proceedings of the Royal Society B. It overturns the idea that all the sharks are exclusive meat-eaters. Researchers from the University of California, Irvine have found that bonnethead sharks graze upon seagrass happily, in addition to eating crabs, bony fish, snails and shrimp.
Omnivores actually feed on a variety of food of both animal and plant origin. The bonnethead shark is found abundantly in the shallow waters of the Western Atlantic as well as the Gulf of Mexico. Though, bonnethead shark is small by shark standards, adult females — the larger of the two sexes — can still reach a five feet long which is quite impressive. The researchers also analysed the sharks’ dietary habits after reading reports of the fish chomping on seagrass. Seagrass is the flowering marine plant that forms subsea meadows in some coastal waters.
The researchers retrieved some sea grass from Florida Bay. They hauled it back to the lab and re-planted it. The researchers added some sodium bicarbonate powder made with a special carbon isotope to the water as the seagrass took root. This was then taken up by the seagrass, which gave it a distinctive chemical signature. The team of researchers also included a few researchers from the Florida International University in the US. They next caught five bonnethead sharks and brought them to their laboratory.
The five bonnethead sharks were given only seagrass and squid for a period of three weeks. The scientists then ran a number of tests on these sharks. These were able to find out that they successfully digested the seagrass with enzymes. These enzymes helped in breaking down the components of the plants, such as cellulose and starch.
Researchers said that the shark may have to rely just on strong stomach acids to weaken the plants’ cells so the enzymes can have their digestive effects as they lack the kind of teeth which are best suited for mastication.
Well, to many just getting to know what do sharks eat might not be a big thing. However, scientists have put in a lot of efforts to identify the first known omnivorous shark species and the Scoop Cube team appreciates and applauds these efforts.