Recently, a scientific research team confirmed for the first time that an individual humpback whale migrates back and forth between the east coast of Australia and Brazil. Its journey across the Atlantic and Southern Ocean exceeds 14,000 kilometers, setting a new record for the confirmed migration distance of individual humpback whales worldwide. The research was conducted in collaboration with institutions including Griffith University and the Pacific Cetacean Foundation, and the paper has been published in Royal Society Open Science, the journal of the Royal Society.
By comparing a large number of photos of humpback whale tail fins taken over decades, researchers identified two individual whales that had appeared in the breeding waters of Australia and Brazil. The pattern of the humpback whale's tail fin (commonly known as the "tail lobe") is unique, so it can be used as an individual identification mark similar to a "fingerprint", providing a key basis for tracking across generations.
One of the humpback whales was first photographed in Hervey Bay, Queensland, Australia, in 2007, and was observed there again in 2013. In 2019, the same whale was photographed and recorded off the coast of Sao Paulo, Brazil. The straight-line distance between the two places is about 14,200 kilometers, which is close to the distance from Sydney to London. The actual swimming route may be longer.
Another humpback whale set a new record. Researchers first recorded the individual in 2003 in Brazil's Abrolhos Bank, an important humpback whale nursery off the coast of Brazil, where it was part of an active group of nine adult whales. Twenty-two years later, in September 2025, the same whale was found moving alone in the waters of Hervey Bay, Australia. The straight-line distance between the two observation points was about 15,100 kilometers, making it the longest known migration distance of the same humpback whale recorded so far.
This result relies on 19,283 high-quality tail fin photos collected from 1984 to 2025 in the waters of eastern Australia and Latin America. Image sources include both professional scientific research teams and public “citizen scientists” who submitted observation photos through Happywhale, a global whale identification platform. The researchers used an automatic image recognition system to screen for possible matching photos, and then manually reviewed them one by one, finally identifying the two individual humpback whales that had completed their transoceanic journey.
Research shows that in data spanning more than 40 years, there are approximately 20,000 identified individual humpback whales, and only two have been confirmed to travel between the breeding waters of Australia and Brazil, accounting for approximately 0.01%. Scientists believe that such trans-oceanic exchange events are extremely rare, but are of great significance to the long-term conservation of species and help maintain genetic diversity among different breeding groups. The researchers also pointed out that the movement of individuals between different sea areas may carry local "song patterns" and promote the cultural spread of humpback whale courtship songs on a trans-oceanic scale, similar to the spread of musical trends in human society.
This research also provides new supporting evidence for the so-called "Southern Ocean Exchange Hypothesis." According to this hypothesis, humpback whales from different breeding populations forage together in the waters around Antarctica, and some individuals choose different migration routes during subsequent migrations, thus "joining" another breeding group in distant waters. Scientists speculate that climate change-driven changes in the extent of Southern Ocean sea ice and the distribution of key prey such as Antarctic krill may be affecting the frequency of these rare transoceanic migrations.
Scholars involved in the study pointed out that it was long-term, transnational, and multi-party monitoring projects that allowed such extreme individual migration cases to be discovered and confirmed. The research team emphasized that public participation in data collection not only increased sample size and regional coverage, but also increased society's attention to cetacean protection and the health of the marine ecosystem.