Bonnethead shark “the first known omnivorous species of shark,” says researcher Samantha Leigh, co-author of the new study. This omnivorous shark is said the hammerhead relative, a lover of seagrass.
The Guardian reported that up to 60% of the bonnethead shark’s diet is seagrass. These are found in coastal waters around the Americas, with the rest being bony fish, crabs, snails, and shrimp, living.
Initially, researchers knew of bonnethead sharks eating up the marine plant but “it has been assumed by most that this consumption was incidental and that it provided no nutritional value,” says Leigh. After a series of tests, it is known that’s their feed.
Researchers captured five bonnetheads which are five feet long for the tests and put them through a three-week diet of squid as well as seagrass. They’ve got a distinctive chemical signature.
The chemical signatures from the sharks included enzymes to break down starch and cellulose, strong stomach acids might also be at play. The sharks digested more than half of the organic material in the grass.
They were better at digesting plant material than pandas as per Mashable and “on a par with young green sea turtles,” per the Guardian.
The sharks’ blood and liver tissue are tested and a carbon isotope added to the seagrass was also found indicating the plant does serve a nutritional purpose for the sharks.
However, the ecological implications of 4.9 million bonnethead sharks eating up on seagrass are not yet fully understood.