Whale Supergroups Signal a Comeback, Yet Shipping Surge Threatens Their Future

When Chris and Monique Fallows set out in their small boat off the west coast of South Africa last December, they expected the usual sight of solitary humpbacks or perhaps a modest pod. What they witnessed instead was something that looks like a skyline of spouts – almost three hundred whales surfacing together, a phenomenon scientists call a “supergroup.”

Chris, a veteran wildlife photographer, described the scene as “extraordinary,” noting that the plumes of breath rose one after another, turning the ocean into a misty cityscape. The couple counted the animals by photographing each fluke – the unique pattern on a whale’s tail – a technique that lets researchers identify individuals without ever getting too close.

According to Alex Vogel, the Africa coordinator for the citizen‑science platform Happywhale, this was likely the largest humpback aggregation ever recorded in the Southern Hemisphere. Their database, built on thousands of public submissions, confirmed the Fallows’ count of 299 whales.

Scientists say this surge is no accident. Since the International Whaling Commission imposed a global hunting moratorium in 1986, humpback numbers in the southern oceans have swelled from under 10,000 to well over 100,000. “The ban on commercial whaling is one of the greatest marine conservation successes,” says Dr. Els Vermeulen, chief scientist at the University of Pretoria’s Whale Unit.

Supergroups usually form in areas teeming with krill and small fish, the primary fare for humpbacks. The loud vocalizations of feeding whales can attract more members, creating a feedback loop that draws hundreds into a single feeding hotspot.

But the good news is tinged with worry. Shipping traffic around the southern tip of Africa has exploded – roughly quadrupling since late 2023 – as vessels avoid the Red Sea amid the Israel‑Hamas conflict and the broader Iran‑Houthi war. More ships mean more chances for fatal collisions, a risk that’s already being felt. Cape Town’s coastal manager, Gregg Oelofse, has reported a growing number of whale carcasses bearing propeller scars.

Because a whale that sinks leaves little trace, the true toll is hard to quantify. Nonetheless, the pattern is clear: more ships, more danger. Conservationists are now lobbying for mandatory speed limits and better monitoring near South Africa’s coast, hoping to give both mariners and whales a little more room to breathe.

While humpbacks enjoy a remarkable comeback, other great whales remain in precarious positions. Seven of the 14 species are listed as endangered or vulnerable, with the North Atlantic right whale teetering at just a few hundred individuals.

The story of the Fallows’ supergroup is a reminder that nature can heal when given a chance, but it also underscores how human conflicts far afield can ripple back to the seas we share.