Watch what can happen when killer whales tangle with great white sharks

Watch what can happen when killer whales tangle with great white sharks
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Great white sharks are the ultimate predator. In the ocean, these toothy creatures easily hold one of the top spots on the food chain (though the odds of one killing a human are 1 in 3,700,000). Recent drone and helicopter footage of an underwater attack shows that another marine mammal appears to have the upper hand.

For the first time, biologists captured direct evidence of killer sharks attacking and killing white sharks off South Africa. The first video was captured by drone in May 2022 in the Mossel Bay region, revealing three orcas cornering and fatally biting a three meter-length white shark. After the bloody battle, the shark’s body wasn’t seen or recovered. This video, along with extended helicopter footage of this attack and shark tag data, were published this week in the journal Ecology.

YouTube video

The first video of a drone pilot was released in June. However, the team received cell phone footage from a helicopter pilot later that day. They were able to identify that the killer whales in the helicopter video were the same ones in the drone pilot video–spotting a particularly well-known shark hunter, named Starboard. The evidence suggests that the pod went on an hour-long hunt, potentially killing four white sharks. The researchers made adjustments and submitted the paper again with the new information. This gives new insight into the seldom-seen evasive behavior and habits of great whites, a species that once dominated South African waters. However, it is now in rapid decline ..

“I still remember viewing the footage for the first time and feeling a whole mixed bag of emotions,” Alison Towner, lead study author and senior shark scientist at Marine Dynamic Academy in Gansbaai, South Africa, told PopSci in an email. “We had been analyzing evidence on these interactions since 2017 and had often been challenged on whether this really was occurring in South Africa. The footage is irrefutable proof that orcas hunt white sharks here

[Related: Even blue whales aren’t safe from orcas]

Orcas look like “wolves of ocean” Towner says, as they often capture prey in organized groups. The team was able witness two recorded attacks where killer whales approached sharks very closely in slow motion. The great white will swim in close circles around the orca, keeping it within reach. Sharks are highly visual creatures and won’t flee. Towner explains that this is a common tactic that turtles and seals use to avoid sharks. However, killer whales hunt in groups so this tactic may not work as well.

” I was in awe at how orcas hunt and strategize, but one can’t help but feel for sharks too,” Towner said. “It’s quite disturbing to see white sharks being killed by larger predators.”

The orcas seem to love liver, in particular. The video shows the orcas gnawing on the sharks’ stomachs and tearing their liver. It could be seen floating to where the killer whale eats it. Towner explains that white shark livers are rich in nutrients and oil, making them an ideal meal. The team explained in the study that the footage provides an explanation for shark carcasses washed up on the beach that had missing livers.

This might actually be a relatively common phenomenon. Killer whales are the only known marine predator of great white sharks. In South Africa, Starboard, and partner-in-crime Port, have been reported preying on other shark species and have been linked to white shark deaths since around 2017, but this is the first time the showdown was seen in action. Before killer whales began hunting in Mossel Bay white sharks were often seen, sometimes being recorded daily by research surveys. The study authors collected data from drones and dive boats before and after the predation events and found that white sharks fled the region immediately after the attacks. Only a single white shark was seen in 45 days after the predations were reported.

[Related: Great whites don’t hunt humans–they just have blind spots]

“Killer whales are highly intelligent and social animals,” marine mammal specialist and study co-author Simon Elwen said in a press release. They are known to learn and pick up behaviors or skills from each other in their unique cultural system.

If the hunting practice spreads to killer whales over time it could be difficult to be a shark swimming in South African waters. Orcas are already pushing great whites out of Gansbaai, a fishing town east of Cape Town that’s popular for shark tourism. Towner explains that shark numbers have been declining due to climate change and fishery activities. Orcas add an additional pressure to the mix, so Towner and other researchers are keen to monitor shark and orca dynamics and any potential impacts it might have on South Africa’s ocean ecosystem.

” While these interactions may be captivating, it is important that you understand that white sharks are under threat in South Africa. Orcas now pose a further threat to their fragile populations.” Towner said. “This information will be used in future studies and management here in South Africa

Lauren J. Young

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