[imagesource: Discovery]

Port and Starboard, two infamous orcas (or killer whales) that frequent our waters, have taken a liking to great white shark liver.

They show no signs of slowing down and when a great white carcass was found in Hartenbos, Mossel Bay, in August, they were once more the prime suspects.

Footage captured earlier this year offered the first direct evidence of orcas killing white sharks in South Africa and was heralded as “probably one of the most beautiful pieces of natural history ever filmed” by researcher Alison Towner.

The clip, which was just a snippet of an hour-long hunt of multiple sharks, aired on the Discovery Channel and shows the orcas taking out a nine-foot (roughly 2,75-metre) great white. One comes to the surface with the shark, having targeted the liver area, and blood spills out.

At the time, it wasn’t made clear whether Port or Starboard was involved. This morning, Sea Search Research & Conservation released further information via its YouTube channel and a press release:

The new paper [published today in The Ecological Society of America’s journal Ecology] offers more extensive footage, along with data from tags, drone surveys and shark-tour boats showing that white sharks fled from the Mossel Bay region of South Africa for several weeks. Orcas have been observed preying on other shark species, but direct observation of predation on white sharks locally has been lacking – until now…

Only two killer whales in South Africa have been previously linked to hunting white sharks, but never actually seen ‘in action’. Only one of those animals was observed in the new footage, along with four other killer whales. The authors believe that the involvement of these four new whales suggests the behavior may be spreading.

Starboard was part of the attack pod but it was actually another orca that bit into a white shark at the region of the liver.

Should this behaviour be adopted by more orcas, it’s likely to have far wider impacts on shark populations.

The paper’s findings are broken in down in this excellent video:

[source:seasearch]