Home Biologist The “serial” killer whales strike again

The “serial” killer whales strike again

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The normally blue-black eyes were void of all life as a wave lapped lazily against them, gently swaying the animal to which they belonged. Once a feared predator, this great white shark succumbed to an injury caused by an even more frightening enemy: killer whales.

This ongoing battle between great white sharks (Carcharodon carcharias) and orcs (Orcinus orc) has been underway off South Africa for years. Between February and June 2017, five white shark carcasses washed up on Gansbaai Beach in the Western Cape Province. A recent article published in the African Journal of Marine Science concluded that the same pair of killer whales had killed eight great white sharks since 2017 in the same area. Targeting the insides of sharks (primarily their livers, though some sharks have also had their hearts removed), black-and-white predators always leave a calling card: a large, clean hole in the center of the shark’s chest. “It’s very precise. [wound]Alison Towner, senior white shark biologist at Rhodes University in Makhanda, told 9news.com.au. “Orcas work together to tear apart sharks.”

It is thought that the killer whales responsible for these killings may belong to a rare shark-eating body type. Named port and starboard, these adult male killer whales are known to love feasting on high-energy shark livers. Until recently, scientists only saw the bloody consequences of the battle between two giants of the oceans. However, drone footage shown as part of this year’s ‘Shark Week’ on the Discovery Channel captured a pod of killer whales killing a great white shark in a highly coordinated attack in Mossel Bay. Streamed around the world, the video shows one of the killer whales ripping out the shark’s liver and eating it.

But this last murder? It was something new. Towner shared photos of a freshly killed subadult female great white shark. Found at Hartenbos (Mossel Bay) – the first time a killer whale-killed great white has been found in the area – it was dumped at sea after photos and measurements were taken. “The killer whales seem to be more focused on this site now,” she said, adding that she believed the same two killer whales were responsible for the killing. “These are injuries identical to those of other sharks killed.”

Why the killer whales appear to have changed their hunting grounds is currently unknown, but Towner and other local scientists are keen to see if more bodies will wash up…and what that means for the sharks in this area. . For now, they have more questions than answers.