A humpback whale has decided that the usual 10,000km round trip between Antarctica and the Great Barrier Reef just wasn't cutting it, so it went ahead and swam from Brazil to Australia instead - a jaunt of about 15,100km that researchers say is the longest distance ever documented between sightings of an individual humpback.

The whale was first photographed in 2003 at the Abrolhos Bank, Brazil’s main humpback whale nursery off the coast of Bahia. Then, in September 2025, it showed up in Hervey Bay off the Queensland coast. That's a gap of 22 years and roughly 15,100km - giving new meaning to the phrase "long time, no see."

Stephanie Stack, a PhD candidate at Griffith University and co-author of new research published in Royal Society Open Science, called it "extraordinary to photograph a whale that’s gone this distance - it has never happened before." She also noted that the whale hadn't been sighted for 22 years, which is "really remarkable in and of itself."

The whale was identified through Happywhale, a platform co-founded by study co-author and Southern Cross University whale biologist Ted Cheeseman. The site uses an AI algorithm to match fluke photos - the underside of whale tails, which are as unique as human fingerprints. Because nothing says "individuality" like a tail pattern.

Researchers also found a second whale: photographed in Hervey Bay in 2007 and again in 2013, then spotted off the coast of São Paulo in 2019 - a distance of about 14,200km. These represent "the first recorded exchange in both directions" between Brazilian and eastern Australian humpback populations. The researchers note that resighting intervals of six and 22 years suggest these are rare, possibly single-lifetime events, not regular migratory shifts.

The study drew on 19,283 fluke photos collected between 1984 and 2025 from eastern Australia and Latin America. The two long-distance travelers accounted for only 0.01% of identified whales - so, statistically speaking, this is the marine equivalent of winning the lottery.

Stack acknowledged the limitations: "We know where it started, and we know where it ended up, but we don’t know anything about what happened in between." The whales could have traveled even farther than the straight-line distances, and their exact routes remain a mystery.

For context, the typical Australian humpback migration is a 10,000km round trip between Antarctic feeding grounds and Great Barrier Reef breeding grounds. These two whales apparently looked at that and thought, "Nah, let's take the long way."

Stack said the discovery is "a good reminder that conservation of our marine resources needs to be collaborative between nations, because these are migratory animals that move across borders and between countries." She also noted it's "very likely" that climate change will affect migration patterns in future, pointing to dramatic changes in the Southern Ocean feeding grounds, with Antarctic krill populations under threat.

So while this whale may have set a record, it might also be a sign of things to come - as if we needed another reason to worry about the planet.