Cow sharks found on Betty’s Bay beach were killed by infamous orca duo
The orcas, named Port and Starboard, are believed to be the same ones that have been killing sharks over the past few years along the Western Cape coast.
Oxford called on experts Meaghen McCord and Pippa Ehrlich, who came from Hermanus and Simon’s Town respectively to investigate the scene.
Five dead cow sharks were recently found on main beach at Betty’s Bay in the Western Cape. The sharks are also known as sevengill sharks and are very rare, reports Alberton Record.
Meagen McCord, director of the South African shark conservancy in Hermanus, says all five were killed in the classic modus operandi used by killer whales or orcas where the orcas grab a pectoral fin each, flipping the shark over and tugging to split open the throat and chest cavity where they then suck out the liver.
The liver is the only part of the shark that they eat as it is high in nutrients.
ALSO READ: Orcas kill three great white sharks near Cape Town for their livers
The two male orcas thought to be responsible for the recent attacks are the same orcas responsible for the precision-killing of a number of great white sharks over the past few years.
According to a Facebook post by Pete Oxford, they have been at it again. The orcas have even been named – they are called Port and Starboard.
When the sharks were found earlier in May, they all showed exactly the same apparent cause of death. Namely that their throats seemed to have been ripped out with almost surgical precision in each case.
Shark expert Pippa Ehrlich examining the shark carcasses. Picture: Pete Oxford
Oxford called on experts Meaghen McCord and Pippa Ehrlich, who came from Hermanus and Simon’s Town respectively to investigate the scene.
They confirmed that the sharks had indeed all been killed by killer whales. The wounds were consistent with the orca theory and once the carcasses were opened, the livers were found to be missing.
Oxford added that the infamous duo, Port and Starboard, identifiable as each has a distinct, flopped-over dorsal fin, were known to be in the area.
According to a research paper titled Running scared: when predators become prey, which was co-authored by Dr Alison Kock along with Tamlyn M. Engelbrecht and M. Justin O’Riain, these super predators are known to specialise on certain prey species, and up until 2015 were only documented preying on marine mammals within False Bay.
“However, in 2015 and 2016 we documented two events in which killer whales preyed upon broadnose sevengill sharks, using a specialised feeding method in which only the liver of each shark was consumed.
“Although selective feeding on shark liver by killer whales is established, this is the first record of killer whale predations on sevengill sharks in False Bay, and the first documentation of a novel feeding technique, in which killer whales used force applied to the pectoral fins of each shark to rupture the pectoral girdle and thereby access the liver.”
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