Great White Sharks With No Organs Found in South Africa, Two Orcas Possible Culprit

Off the coast of South Africa, two killer whaleshave taken a liking to the great white sharks' internal organs, driving the top predators away from a popular spot for shark watching and upsetting the marine ecosystem.

A killer whale pair that scientists think has been killing great white sharks and eating their livers is the subject of a recent study published in the African Journal of Marine Science. Sharks have left the areas they had long controlled in favor of avoiding conflict with the new predators.

In the Western Cape, close to Gansbaai, eight great white shark carcasses have washed up on beaches since 2017. Seven of them had their livers removed and some of them had their hearts removed. According to researchers, the same pair of orcas made their wounds, which are easily distinguished.

Shark-Watching Spot Without Sharks to Watch

Tourists are drawn to the popular shark-watching location of Gansbaai, which is east of Cape Town, for pursuits like cage diving. The sharks appeared to leave the area quickly, according to tagging data, and sightings did decline in the years following the orca attacks, according to the researchers.

Alison Towner, the lead author of the study and a senior white shark biologist, pointed out that in Gansbaai, individual Great White Sharks typically disappeared for several weeks or months after an Orca attack. The longer the Great White Sharks stay away, the more frequently the Orcas visit these locations.

Since data collection started in Gansbaai, there were only two instances before these shark predations where they went missing for a week or more. They were not present in 2007 nor again in 2016, Huffington Post reports.

Towner observed that the essential balance of the ocean ecosystem is being upset by the great white sharks' long absence. If there are no sharks to feed on cape fur seals, the seals can hunt more endangered African penguins or fight for the small fish that the penguins eat.

The bronze whaler shark, known to be eaten by great white sharks, has also emerged as a new mid-level predator as a result of this. However, orcas also seem to be consuming bronze whaler sharks.

Although it is only a hypothesis at this point, Towner asserted that there is a limit to how much stress an ecosystem can withstand and that the effects of orcas killing sharks are probably much more widespread.

Killer Whales, Great White Sharks, Bronze Whaler Sharks

One of the most potent predators in the world, orcas, also known as killer whales, are the largest of the dolphin species.

The largest predatory fish on Earth, great whites are found in cool, coastal waters all over the world. They can grow up to 15 feet in length on average, but records exist of specimens that were 20 feet long and 5,000 pounds in weight.

Copper sharks are another name for bronze whaler sharks. The species has a bulge at the base of the upper caudal fin and a long, moderately rounded, broad snout. Most fins have dusky edges and are typically white below and olive-grey to bronze above. A light blaze runs along its flanks from the dorsal fin to the tail.