Pair of Great White Shark-Eating Orca Return to Hunting Ground

A pair of orca known to hunt great white sharks have been spotted off the Western Cape in South Africa recently, with the animals previously linked to declining shark activity in the region.

The Seafari app, which allows users to document their sightings of marine life and post them online, announced the sighting in a Twitter post on Monday (January 17.) It said that the sighting occurred a day earlier on Sunday.

Referencing the specific features of their collapsed dorsal fins that identify the animals, Seafari said that the two famous orca called Port and Starboard who are known to hunt sharks together were seen again in the area.

The pair have been sighted in False Bay and nearby Gansbaai, South Africa, at least 41 times since 2015, and official reports have suggested their presence could be linked to declining white shark activity in the area.

Whale watching tour operator David Hurwitz, of Simon's Town Boat Company, told Newsweek: "They were first seen in 2009 (Lüderitz) and then again in 2013 (Port Elizabeth), but other than noting their collapsed dorsal fins, they were merely recorded along with other killer whale sightings, not realizing at the time how famous or notorious they would become.

"It was in 2017 that Port and Starboard hit the headlines, because by then, they appeared to have moved onto bigger prey—great white sharks! Over the course of that year, five great white sharks washed ashore in the Gansbaai area with similar trauma to cow sharks found in False Bay."

False Bay was once a great white hotspot, with the sharks there famous for their breaching behavior. Normally, beach safety program Shark Spotters would count between 200 and 250 great whites in the area every year. But since 2017, these sharks have almost vanished.

In December, Shark Spotters CEO Sarah Waries told South African Broadcasting Corporation that just five great white sharks were seen in False Bay over 2021.

In 2020, orca were linked with a number of shark corpses examined by scientists that were missing their livers, prompting speculation that the orca were hunting sharks in the area specifically to eat this nutrient-rich organ.

A report published by the South African government's Department of Environment, Forestry and Fisheries in October, 2020, showed that the presence of orca known to hunt white sharks had been linked to declining shark activity in South African waters.

Authored by an expert panel, one line in the report read: "The Panel noted with concern the disappearance of the white sharks from eco-tourism hotspots, but concluded that these were more likely a shift in distribution from west to east as a result of recent orca occurrence and predation, rather than being related to the fishing activity of the demersal shark longline fishery.

"The Panel found some evidence for a causative link between the appearances of a pod of orcas that had specialized on preying on white shark."

Other scientific reports have also linked the presence of orca to declining shark activity in the areas they frequent.

A 2019 study in Scientific Reports that examined white shark and orca encounters off the coast of California found that even just brief appearance of orca in an area near the Southeast Farallon Islands seemed to scare white sharks away from the area.

"In multiple instances, brief visits from killer whales displaced white sharks from SEFI, disrupting shark feeding behaviour for extended periods at this aggregation site," the study said.