You have likely heard of humpback whales, but have you heard of humpback dolphins?

Currently, there are around 38 recognised species of oceanic dolphins worldwide, belonging to the family Delphinidae.

There are around 18 species found in the waters of South Africa but there are just 3 species that can be spotted from our shark cage diving vessel in Gansbaai: The Indo-Pacific Bottlenose Dolphin, the Long-beaked Common Dolphin, and the Indian Ocean Humpback Dolphin.

In this blog, we will be discussing the Indian Ocean Humpback Dolphin.

What do Indian Ocean Humpback Dolphins look like?

The Indian Ocean Humpback Dolphin is one of four humpback dolphin species which are all characterised by a hump on their back, upon which the dorsal fin sits.

All four species begin life looking quite similar but as they mature, they develop distinct differences in hump size and body colouration. The Indian Ocean Humpback generally has the largest, most conspicuous hump.

They are mainly dark grey, with lighter grey on their belly. However, they are more easily identified based on their geographical location. This is because there is very minimal overlap between the species populations.

The Indian Ocean Humpback Dolphin is the only humpback dolphin found in South Africa.

Ecology: Behaviour and Diet

All humpback dolphins prefer nearshore (within 1–2 km), intertidal, and estuarine waters that are less than 25 metres deep. In theory, this makes them an excellent target for marine watching tours, however, the humpbacks are relatively shy so sightings can be a rare occurrence.

Furthermore, humpback dolphins usually occur in small pods of 2-6 individuals, whereas the bottlenose and the common dolphin are often found in larger numbers. We have been very lucky recently, with multiple humpback dolphin sightings from our boat this month!

Humpback dolphins are opportunistic feeders; meaning they feed on a wide variety of prey, often what is readily available. Although fish is the primary target for their diet, they can also feed on squid, octopus, and crustaceans.

A scientific article published at the end of 2025 investigating the stomach contents of deceased humpbacks suggested that their diet has shifted over the past five decades, with new prey species being introduced along the way and other prey being lost.

Being opportunistic feeders also means they have a variety of hunting techniques for catching prey.

They can herd fish against shorelines, forage along the sea floor, partially strand themselves, and they have even been known to follow fishing trawlers to seize discarded and escaped fish.

Conservation Status

According to the International Union for Conservation of Nature (IUCN) Red List of Threatened Species, the Indian Ocean Humpback Dolphin is an endangered species with population numbers on the decline, as of the 2022 assessment.

It is estimated that there are fewer than 500 individuals remaining along South Africa’s coastline. Human activity is believed to be a major driver of this decline.

The humpbacks live so close to shore, making them vulnerable to heavy human activity including coastal development, vessel traffic, pollution, shark nets, and fishing.

Protecting these unique dolphins will depend on careful management of South Africa’s coastal ecosystems and reducing the threats they face, allowing their population numbers to recover.