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Published 15:28 09 Oct 2022 GMT
Mindblowing footage shows a pair of orcas attacking and killing a great white shark before feasting on its liver on South Africa's Gansbaai coast.
The deadly duo has been the subject of extensive research, following eight great white slaughterings since 2017.
The Ecological Society of America (ESA) detailed that the orcas, named Port and Starboard, were finally captured in the act using drone and helicopter pilots.
A clip from the attack was aired in June, however, the short video was just part of a prolonged hour-long incident. Researchers believe that this is clear evidence that orcas are "capable of pursuing, capturing and incapacitating white sharks," per the ESA.
Senior shark scientist at the Marine Dynamics Academy in Gansbaai, Alison Towner, said: "This behavior has never been witnessed in detail before, and certainly never from the air."
Multiple killer whales were recorded, shattering previously held beliefs that the shark murders were attributed to just Port and Starboard.
The research - published on October 3 in The ESA's journal, Ecology - also demonstrates the methods used by great whites to evade the orcas. Per the video footage, the orcas are seen slowly approaching the shark, which remains close to the predators to keep them in view - this method is often used by turtles or seals when evading sharks.
However, given that orcas hunt in groups, researchers believe that his method is ineffective for sharks.
Dr. Simon Elwen, Director of Sea Search and a research associate at Stellenbosch University, said, per the ESA: "Killer whales are highly intelligent and social animals. Their group hunting methods make them incredibly effective predators."
After sightings of Port and Starboard, researchers noted that great white sharks were then noted as being absent from those areas for weeks or even months.
Interestingly, after the orcas feast on a shark's liver, the organ releases a yellow-tinged substance called A-2. This substance has been studied by scientists in the Bahamas, who have discovered that this acts as a potent repellent to other sharks, per CBS News.
"You introduce this chemical, and they all leave," one researcher, Eric Stroud, said. A-2 allegedly carries a "chemical messenger" that triggers a flight response from other sharks, perhaps why many great whites are now known to evacuate areas where killer whales have been spotted.
This was mirrored by a further ESA researcher and shark expert, Dr. Alison Kock, who stated: "We first observed the flight responses of seven gills and white sharks to the presence of killer whales Port and Starboard in False Bay in 2015 and 2017. The sharks ultimately abandoned former key habitats, which has had significant knock-on effects for both the ecosystem and shark-related tourism."
