International Whale Shark Day: Shark-Cams Reveal the Secret Feeding Lives of Ocean Giants
To celebrate International Whale Shark Day, new research is giving us a fascinating shark’s-eye view of how the world’s largest fish finds its food
Scientists from the Australian Institute of Marine Science (AIMS) and Murdoch University fitted cameras and movement sensors to juvenile whale sharks gathering at Ningaloo Reef in Western Australia, allowing researchers to follow the animals beneath the surface and see behaviours that would normally remain hidden.
Combined with a review of more than 100 scientific papers, the footage helped researchers identify 36 distinct whale shark behaviours – including 12 associated with feeding. Six of these feeding behaviours had never previously been documented.
Among the discoveries was ‘gliding slow feeding’, where a whale shark effectively sinks through the water with its mouth open, collecting prey as it goes. Researchers also recorded ‘dive feeding’, with sharks swimming towards the seabed while continuing to feed.
The cameras revealed that feeding wasn’t restricted to the surface either. Whale sharks were seen using different feeding strategies throughout the water column and along the seabed, at depths of up to 70 metres.
Most of their time was spent using low-effort feeding techniques, effectively ‘snacking’ on small amounts of prey until they encountered something more substantial, such as a swarm of krill, when they switched to more active feeding.
Researchers believe this remarkable flexibility may help explain how whale sharks thrive in tropical waters where food can be scarce and patchily distributed.
The findings also highlight the importance of Ningaloo Reef as a protected feeding ground for these endangered ocean giants.
So, on International Whale Shark Day, it seems there’s still plenty to discover about the biggest fish in the sea – including the fact that whale sharks may just be the ultimate underwater snackers.
