A male humpback whale has made an extraordinary journey from South America to Africa — travelling more than 13,046 kilometres (8,106 miles) — the longest migration recorded for a single whale, a new study found. The intrepid marine giant’s trek also marks the first documentation of an adult male humpback travelling between the Pacific and Indian oceans.
The humpback was first spotted off the coast of Colombia in 2013 and seen again a few years later not far from his original location. But in 2022, the whale was unexpectedly detected in the Indian Ocean near Zanzibar, off the coast of East Africa.
The typical migration route for humpback whales can exceed 8,000 kilometres (4,971 miles) in a single direction, making this one’s journey close to two times that of most whales, according to the study that published Wednesday in the journal Royal Society Open Science.
“These animals are distinct individuals, and they’ll do surprising things,” said study coauthor Ted Cheeseman, a marine biologist at Southern Cross University in Australia. “These oceans are very much connected spaces, and whales travel beyond borders.”
To track the whale’s migration patterns, the study authors used a platform called Happy Whale, which Cheeseman cofounded. It allows citizen scientists, researchers and whale watchers to contribute photos of their whale sightings.
An unusual journey
Humpbacks live in oceans around the world and are known for completing some of the longest migrations of any mammal, but this whale’s travels are special due to his movement between two breeding grounds.
Humpback whales typically return to specific breeding locations each year because whale populations tend to be geographically distinct.
For example, one of the humpback populations in the North Pacific migrates to feed in waters around Alaska during the summer and spends the winter in waters around the Hawaiian Islands to breed, birth and nurture calves, while two populations in the North Atlantic feed all the way from the Gulf of Maine to Norway and migrate to the waters of the West Indies and Cape Verde off the coast of Africa in the winter.
This whale, however, migrated between two distinct breeding stocks in different oceans.
“Our dogmatic thinking is that (whales) always go to the place where they came from,” said Ari Friedlaender, professor of ocean sciences at the University of California, Santa Cruz, who was not involved in the study. “But there has to be some movement where you get some (animal) explorers that decide, for whatever reason, to follow a different path.”
Humpbacks also navigate with remarkable precision, according to Cheeseman, and since this whale isn’t a juvenile, it’s unlikely he would have ventured out of his breeding zone because of disorientation.
Instead, social or environmental factors may have propelled this migration, Cheeseman said.
The whale had likely been in competition with other males for mates in Colombia, according to Cheeseman, and it’s possible he travelled to look for a less aggressive environment. He also suggested that food scarcity in the region could have played a role in this unusual migration.
Tracking the whale
Every whale has a unique identifier — the underside of its tail — that helps in the tracking.
“When (whales) dive, they lift their tails, and anyone taking a picture of their tail can record the identity of the animal,” Cheeseman said.
While this recognition technique has been used since the 1970s, the platform Happy Whale enables researchers and citizen scientists to contribute to a global catalog of whales, paving the way for international collaboration.
“(Happy Whale) is going to bring more opportunity for sharing and networking to make our global research partnerships more inclusive,” Friedlaender said.
The database currently includes around 109,000 individual whales, according to Cheeseman.
Until this whale is spotted again, his exact whereabouts are unknown. However, Happy Whale’s system allows for the ongoing tracking of whales, which may provide further insight into current and future migratory patterns.
“With every photograph we receive we’re looking for every whale we know,” Cheeseman said.
The future of migration
Whaling in the 20th century killed nearly 95 per cent to 99 per cent of the humpback whale population in the Indian Ocean, according to Cheeseman.
As a result, little information remains about the behavior and lives of humpback whales in that region.
“We’re looking at their behavior like going into a kindergarten classroom,” Cheeseman said. “There’s maybe one adult, someone who’s middle-aged and a whole bunch of children.”
With young humpback whales predominating in the Indian Ocean, the population and culture of whales in the area are undergoing a major transition.
When a humpback — such as this male — migrates outside of usual patterns, it’s uncertain whether the whale will be accepted or rejected by others in the new breeding ground due to the creature’s “foreigner” status.
However, if exceptions to standard migratory patterns continue, Cheeseman suggests that humpback whales may adopt behaviours from other populations.
“These different paths can connect populations that we otherwise would never think would be in touch with each other to share information and genes that make these populations into more of a global community,” Friedlaender said.
