Are orcas responsible for great white shark deaths in South Africa?

Scientists in South Africa have been examining the bodies of three great white sharks that have washed up off the coast of Gansbaai on the western Cape.

The sharks, up to 5m long, had their oil-rich livers missing, with the most likely explanation that they were probably preyed on by orcas.

The two predators are often found sharing the same habitat where there is large available prey such as seals, and some populations of orcas are known to feed on other species of sharks. However, incidents involving orcas hunting great whites have only been recorded on a few occasions, most notably in California and Australia.

Like many sharks, Great Whites are endangered and according to researchers from the Dyer Island Conservation Trust who have carried out a photo-id study, the population in the area is thought to be no more than around 1,000 sharks. The organisation has seen increased orca sightings in the area in recent years.