Humpback Whale Resighted 15,100km Away After 22 Years
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- A humpback whale photographed at Brazil's Abrolhos Bank in 2003 was resighted in Hervey Bay, Queensland in September 2025 — a ~15,100km journey that researchers believe is the longest documented between-sightings distance for an individual humpback.
- Happywhale, the citizen-science platform co-founded by whale biologist Ted Cheeseman, matched the 22-year-old photos using AI to identify whales by their flukes, which co-author Stephanie Stack called unique "very similar to the way fingerprints are unique to humans."
- A second humpback photographed in Hervey Bay in 2007 and 2013 was spotted off São Paulo in 2019, covering ~14,200km — and together with the first whale, represents "the first recorded exchange in both directions" between Brazilian and eastern Australian populations.
- The two whales accounted for just 0.01% of the 19,283 identified individuals in the Royal Society Open Science study, which drew on fluke photos collected between 1984 and 2025 and described such journeys as "rare, possibly single-lifetime events."
- Stephanie Stack, the Griffith University PhD candidate who co-authored the study, cautioned the whales may have swum farther than the straight-line distances and that climate change is "very likely" to disrupt future migrations as Antarctic krill populations decline.
Why it matters: The match confirms individual humpbacks can cross between the South Atlantic and South Pacific — a journey rare enough (0.01% of catalogued whales) to suggest it's a once-in-a-lifetime event for any given animal. With researchers only able to plot start and end points, the finding underscores the need for international, cross-ocean conservation as climate-driven krill declines threaten the Antarctic feeding grounds these migrations depend on.
