Orcas are systematically hunting great white sharks

in #nature7 years ago

I don't know about you, but I grew up thinking that killer whales - or orcas as they are otherwise known - were a kind of cool, stylish looking whale that didn't really harm anyone; a bit like Arsenal attacking the opposition's goal.

But then as I grew up and learnt more about them, it became apparent that the word 'killer' in the name wasn't a vague reference to their sleek skin colouring or size, but the fact that they are absolute savages. The apex predator. Even above great white sharks.

Indeed, long known to be one of the more cerebral members of the animal kingdom, it seems as though orcas have taken the step into brutal, underwater surgery.

In the last couple of years numerous great white sharks, ranging from 2.7-4.9 meters (9ft to 16ft) long have been washed up on the beaches of South Africa, dead. All have the same injury. A jagged incision, running down between the pectoral fins. Directly above the liver.

Which had been ripped out. In every circumstance.

It is believed that orcas have discovered that in place of the swim bladder, sharks instead have an oily liver, rich in the nutrient squalene. It is that they are believed to be after. The rest of the great white shark carcass has been discarded in every instance.

This in itself is a deeply impressive display of intellect in the animal kingdom, but there is more.

It transpires that the orcas have also realised that sharks are susceptible to tonic immobility: a phenomenon where, if tipped upside down, a shark enters into a type of natural paralysis, rendering them helpless against attack. The orcas have been ramming the sharks before flipping them over and holding them upside down in said state of paralysis, whilst another member(s) of the group slice into the shark and remove its liver.

It is almost difficult to conceive such a display of teamwork and synergy coming from mammals, however impressive their intellects are said to be.

I'm a little blown away in truth. What else could they be capable of?

if anyone else has any interesting stories of impressive animal behaviour please do write it in the comments below - I'd love to hear them!