World’s largest omnivore is a fish

by Danielle Koopman, Australian Institute of Marine Science
July 25, 2022

Marine scientists have discovered that whale sharks eat plants, making the iconic fish the world’s largest omnivore.

Whale sharks are filter feeders and have long been observed eating krill at Western Australia’s Ningaloo Reef.

But when researchers analysed biopsy samples from whale sharks at the reef, they discovered the animals were actually eating a lot of plant material.

“This causes us to rethink everything we thought we knew about what whale sharks eat,” said Australian Institute of Marine Science fish biologist Dr Mark Meekan. “And, in fact, what they’re doing out in the open ocean.”

The finding makes whale sharks—which have been reported up to 18m long—the world’s largest omnivore.

Keep reading: https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecy.3818

Read the Ecology paper: https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecy.3818