La Jornada: Two humpback whales break record by swimming between Australia and Brazil

Paris. Two humpback whales, identified thanks to their tail, set a record by traveling between Brazil and Australia, breeding areas separated by more than 14 thousand kilometers, according to a study.

“It is a phenomenon never before documented,” Cristina Castro, main author of the report published in the magazine, told AFP. Royal Society Open Science.

“It is not unusual for an individual to occasionally deviate (from its migratory route), but what was observed here goes much further. These two whales crossed entire ocean basins and were seen in two different breeding areas, separated by thousands of kilometers,” he highlighted.

By analyzing photographs taken by both scientists and amateurs during ecotourism cruises, this Pacific Whale Foundation biologist and her colleagues managed to reconstruct the odyssey of the two cetaceans.

“Each humpback whale has a unique pattern on the underside of its tail. A combination of pigmentation, shape, as well as scars or eventual marks, specific to each individual, like a human fingerprint,” Castro explained.

The scientists analyzed 19,283 photographs collected between 1984 and 2005 in eastern Australia and Latin America using an image recognition algorithm. They then visually verified each possible match and were able to identify two whales present in both regions.

The first was photographed for the first time in 2007 in Hervey Bay, Queensland (east coast of Australia). She was spotted again in the same location in 2013 before reappearing in 2019, this time off Sao Paulo, Brazil.

These two areas are separated by a minimum distance in a straight line of 14,200 kilometers. Since only the starting and finishing points are known, it is impossible to know the exact route the whale followed or the total distance it traveled.

The second cetacean made the reverse trip. It was first photographed in 2003 off Bahia, Brazil, in a group of nine adults. It was identified 22 years later, in 2025, in Hervey Bay, 15,100 kilometers away.

The previous record had been established by a humpback whale between the Pacific coast of Colombia and Zanzibar, in the Indian Ocean, with a journey of 13,046 kilometers.

new songs

Southern Hemisphere humpback whales live in well-defined populations and typically follow the same migratory routes year after year, between feeding grounds in cold waters and their breeding grounds in tropical and subtropical regions.

“Mothers teach these routes to their offspring when they are young, so these trajectories are deeply rooted,” Castro details.

Researchers propose several hypotheses to explain the “exceptional” behavior of the rare individuals who deviate from these routes.

“Oceanographic changes could modify migratory corridors in a way that we do not yet fully understand or “disturbances in their areas of origin could push some individuals to explore more,” says the researcher, who adds that “the availability of food could also play a role.

“Some indications suggest that these exchanges may have been around longer than we think,” he continues.

These movements could contribute to the genetic diversity of humpback whales. And also evolve your singing.

“The males, ‘extraordinary singers’, produce long and complex songs, and these spread almost like a cultural trend,” explains the biologist.

When a male “introduces a new phrase, the others copy it and, in the space of a season, the entire population evolves. If a male from one breeding area arrives at another and starts singing, he could introduce a completely new musical influence,” he emphasizes.