Zoologger is our weekly column highlighting extraordinary animals – and occasionally other organisms – from around the world

Even though it is 4 metres long, this humpback whale calf was no match for a group of dusky sharks

Species: Dusky shark (Carcharhinus obscurus, pictured below)

Habitat: Temperate and subtropical waters worldwide


You’re never big enough to be safe. At least one type of shark seems to have a taste for baby whales.

Spotted off the eastern coast of South Africa, in the Pondoland Marine Protected Area, a humpback whale calf some 4 metres long endured a harrowing ordeal, beset by a group of dusky sharks, each 2 to 3 metres long.

These beasts tend to dine on fish found in coastal and pelagic waters and occasionally marine mammals such as dolphins and porpoises.

But on this occasion, they were more adventurous.

Witness to an attack

For a couple of hours the humpback whale calf swam in circles, pursued by between 10 and 20 sharks, says cinematographer Morne Hardenberg, who witnessed the encounter (see top picture).

The calf was bitten many times, thrashed vigorously at the surface when attacked, and attempted to swim away.

“We stayed with it for a while and it was doing the same manoeuvring, with the sharks following it, and then it just disappeared,” he says. The calf probably drowned from exhaustion, its carcass never recovered – it’s not clear if the sharks ate it in the end.

This is the first time any shark has been directly documented attacking a whale. Other species, such as tiger sharks, are known to be partial to whale meat, but they get it by scavenging.

Matt Dicken from the KwaZulu-Natal Sharks Board in South Africa, who with his colleagues published a report of the incident, believes that such attacks might be more common than we think. “It’s still probably quite rare, but they are happening,” he says.

The East African humpback whale population is growing, so we might see more shark attacks in future, Dicken’s paper suggests.

Apart from humans and the occasional orca known to attack babies, whales don’t really have predators, probably simply because of their size. Humpbacks, for example, grow to some 15 metres long.

Ancient whale eaters

But it wasn’t always like this. The massive megalodon shark, which has been extinct for 2.6 million years, is thought to have preyed regularly on baleen whales, says Samuel Gruber of the Bimini shark lab in the Bahamas. The evidence for this comes from megalodon tooth marks found on whale bones.

Still, sharks are unlikely to pose a regular danger to healthy whale calves, Gruber says, suggesting this calf might have been injured. Or it may have been abandoned by its mother, says Dicken, and so was more vulnerable.

Sardine run

So was this an organised attack to secure dinner?

Sharks are highly social and can hunt cooperatively, says Gruber. This observation happened during the sardine run, a vast fish migration in which cooperative feeding is observed with several shark species, dolphins, sea lions and sea birds, he says.

Dicken doesn’t think that the sharks were actually hunting together. They were probably just aggregating around the calf attacking it opportunistically, he says.

Journal reference: Marine and Freshwater Research, DOI: 10.1071/MF14317

Read more: “When humans attack: The fallout of the shark slaughter“; “Deep sea special: The curious afterlife of whales”

(Images: Top – Morne Hardenberg; Second – Flip Nicklin/FLPA)