Humpback Supergroups in South Africa: Feeding, Not Traffic
Twenty humpbacks in one place is already a lot of whale. Off South Africa’s west coast, researchers have recorded groups much bigger than that. They call them supergroups, and they are about food.
The word can make you picture a whale traffic jam. It is closer to a short-lived feeding party. Humpbacks gather when conditions in the Benguela ecosystem make food easy to find. A 2026 paper uses underwater video to show what the whales do below the surface.
What counts as a humpback supergroup?
Researchers have used a definition of 20 or more humpbacks gathered close together. It is a working definition chosen by researchers, not a law of nature.
A 2025 study brought together reports from scientific surveys, whale-watching operators and citizen-science sightings between 2015 and 2022. It mapped when and where supergroups appeared. The records show that South Africa’s west coast is not only a route past the continent. It can also be a feeding area for humpbacks during the southern summer.
What does underwater video add?
From a boat, you mostly see blows, backs and tails. Underwater footage shows how the whales move inside the group. It gives scientists a view of feeding behaviour that the surface hides.
A 2026 Marine Mammal Science study describes behaviour filmed off Cape Town in 2015 and 2016. It adds detail to the question of how these big groups behave underwater. The paper does not mean every whale works with the others in the same way. It does not mean the animals form a permanent group either.
Why here?
The Benguela system is very productive. Upwelling brings water full of nutrients up towards the surface. That feeds food webs that can draw in fish and, in turn, hungry whales.
Ocean conditions change, so supergroups are not guaranteed to form in the same place every season.
How should people respond?
When many whales feed together, a boat can easily add pressure. Keep clear, move slowly and follow local rules, which can change, so check them on the spot. Do not split the group, cut across its path or follow a whale that moves away.
If the surface looks crowded, give it room. The whales are there to eat. Wildlife encounters are unpredictable. Whale watching should always follow local regulations and experienced professional guidance. So next time you picture a busy patch of ocean, imagine the feeding happening below before you reach for the word “traffic”.
Questions people ask
What is a humpback supergroup?
Researchers have used a definition of 20 or more humpbacks gathered close together. It is a working definition, not a law of nature.
Why do supergroups form off South Africa’s west coast?
The Benguela system is very productive. Upwelling brings nutrient-rich water towards the surface and supports food webs that can draw in fish and feeding whales.
Will supergroups form in the same place every season?
No. Ocean conditions change, so supergroups are not guaranteed to form in the same place every season.
How should boats behave around a feeding group?
Keep clear, move slowly and follow local rules. Do not split the group, cut across its path or follow a whale that moves away.
Wildlife encounters are never guaranteed and never forced. Ocean Calling works only with vetted, ethical local operators, and every animal is free to approach, or not, entirely on its own terms.
Sources & further reading
- Elwen et al. (2026), “Underwater Behavior of Southern Hemisphere Humpback Whales Feeding in Super-Groups, From Video Footage,” Marine Mammal Science.
- Seyboth et al. (2025), “An Update on the Occurrence of Humpback Whale Super-Groups on the West Coast of South Africa.”
- Findlay et al. (2017), “Humpback whale ‘super-groups’: A novel low-latitude feeding behaviour.”
Further reading on Ocean Calling: South Africa in the Ocean Atlas · Humpback whale in the Ocean Atlas · Namibia’s blue and fin whales in the Benguela · South Africa’s southern right whales
Swim with humpback whales in Moʻorea: an ethical whale retreat
Whale encounter retreat · Moʻorea, French Polynesia
Time in the blue, on the whales’ terms. September 2027. If you love whales, this is our whale retreat: small group, slow pace, on the animals’ terms.