Great white sharks have been oddly missing from the coastline of South Africa in previous years, despite speculations pointing to another legendary maritime predator, the orca.
After being filmed on camera devouring one of the world's greatest sea predators, scientists have published fresh research that indicates that orcas pursue great white sharks.
With helicopter and drone footage published this week, a pod of killer whales has been seen hunting sharks for like an hour off the coast of Mossel Bay, a small port town throughout the southern Western Cape region, as reported by Science Alert.
Fresh public research published today in the peer-reviewed journal Ecology of The Ecological Society of America reveals two sets of video evidence, which give additional proof that killer whales can pursue, catch, and incapacitate white sharks. A single predation episode was captured on drone video, but the authors suspect three more sharks were also killed.
Merely two orcas in South Africa have previously been related to white shark hunting, but they have never been witnessed in action. Just one of the animals was seen in the new film alongside four additional killer whales.
Orcas, The Great White Menace
"This activity has not been observed in depth prior, and particularly rarely from the air," said senior author Alison Towner, a senior shark biologist at the Marine Dynamics Academy in Gansbaai, South Africa.
These findings also shed light on sharks' strategies to avoid capture by orcas. In two cases, orcas attacked sharks slowly yet closely, but the shark, rather than retreating, remained near the killer whales, maintaining it in view - a similar method used by seals or turtles to avoid sharks. Moreover, orcas are gregarious and forage for food in groups, as well as researchers believe these traits may make the circling method inefficient in hunting white sharks.
"Killer whales are extremely clever and gregarious creatures." "Their cooperative killing strategies make them highly successful hunters," explained marine animal researcher and research co-author Dr. Simon Elwen, Director of Sea Search and even a research scientist at Stellenbosch University.
Their study demonstrated that such iconic killer whales, commonly known as "Starboard," were members of the pod that ate what was assumed to be a massive chunk of shark liver at the ocean's surface. That new film also showed another killer whale biting a white shark around the liver, as the scientist stated in a report from Forbes.
Still image from a video filmed on a drone by author Christiaan Stopforth, showing the first confirmed observation of a group of killer whales killing a white shark at Hartenbos Beach, Mossel Bay, South Africa.
Following The Predation Occurrences
The current study also examined drone and cage-diving boat survey responses before and after these predation occurrences. White sharks were detected every survey day in the weeks leading up to the predatory episode, and many were sighted at the time of the predations. Yet, just one white shark was spotted in the 45 days following the predations, demonstrating a fled reaction by sharks.
"In 2015 and 2017, we studied the flight behaviors of seven gills with white sharks to the existence of killer whales Starboard and Port in False Bay." "The sharks eventually abandoned former critical sites, which had substantial knock-on impacts on both the environment and shark-related tourism," stated South African National Parks' shark expert and marine scientist Dr. Alison Kock.
Previous research has shown how novel practices proliferate amongst killer whales through cultural transmission over time. As stated by the scientists, if several killer whales begin targeting white sharks, the practice would have far-reaching consequences for shark numbers.
RELATED ARTICLE: 3 Killer Whales Hunt a 9-Foot Great White Shark and Eat its Liver in South Africa [WATCH]
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