Amid the recent great white shark encounters throughout Southern California, and other tragic encounters in Australia, the ocean’s apex predator has received its share of news headlines this year. But after a recent Fox News article published shocking photos of a deceased great white washed ashore in South Africa with giant bites around its corpse, the images suggest that this shark is switching its role from predator to prey.
It seems like great whites are being bumped down a notch in the food chain after four documented shark causalities in S.A. in the last two months. What sea monster could be responsible? None other than the orca.
South Africa's Sunday Times reports that orcas are suspected of killing sharks like the above great white off the country’s Western Cape. Autopsies on the body seem to affirm the theory of orca predation, as the liver of the great white was removed with "almost surgical precision."
Christopher Torchia, a journalist for Fox News, reports in a related article that the orcas target the nutritious oil and fat in organs, like the liver, which can easily be as big as a human. The carcass of the prey is usually abandoned after the orca removes the organs and escapes with its meal. This hunting strategy is common for the species and is seen in their hunting of grey whale calves, where they remove only the tongue, leaving the calf to die from its injuries.
Torchia further explains that the orca can reach up to nine meters in length, considerably larger than the great white. He quotes Boris Worm, a marine research ecologist at Dalhousie University in Canada, who writes that the orca can use "group hunting strategies that can outsmart almost any prey," including the massive sharks. After all, the mammals didn't earn their reputations as killer whales by doing tricks at waterparks; they earned this nickname for their fierce abilities as predators and pack hunters.
Orcas have also been seen attacking sharks off of New Zealand, South America, Australia, and California. Shark cage dive operators in South Africa claimed fewer sightings of great whites around the time of the new attacks, indicating that these sharks have temporarily left the area, possibly as a result of the presence of orca pods. Although some grief has been expressed in the scientific community about losing members of an endangered species, Torchia explains that shark researchers understand how the loss of sharks to predation is part of the natural cycle.
As for orcas developing a taste for surfers, killer whale interventions with humans are statistically even more rare than great white encounters, so you likely won’t need to worry about them in your local lineup. British Columbia’s CTV News wrote a follow-up article in 2013 about surfers being chased out of a lineup by a pod of transient orcas after a YouTube video that captured the event went viral. The crew interviewed Dr. Lance Barrett-Lennard, a senior marine mammal researcher with the Vancouver Aquarium, who explained how orcas are extremely discriminating with what they eat, and that "they know exactly what is food and what isn't." Even still, he advises surfers to leave the water in the event of an orca sighting.
[Featured Image: Hennie Otto / Marine Dynamics / Dyer Island Conservation Trust]