Researchers studying humpback whales off the coast of Western Australia have documented a rare behaviour known as 'gaping', where the animals hold their jaws wide open without feeding. The phenomenon, captured on video by citizen scientists, is thought to be a social display rather than a feeding technique.
Dr Vanessa Pirotta, a whale scientist at Macquarie University and co-author of a new study, said the behaviour was unusual. 'Just when we think we know a lot about humpback whales, we don't,' she said. The study analysed social media footage of 66 humpbacks, including one whale seen pirouetting with its jaw agape.
While baleen whales typically open their mouths wide to feed, the researchers noted that gaping lacks the acceleration and throat expansion of a feeding lunge. It has been observed in breeding grounds and along migratory routes where whales are often fasting, suggesting it may serve a social purpose.
As humpback migration begins along Australia's east and west coasts, whale-watching season is underway. However, increased coastal activity also raises risks of vessel strikes and entanglements. Rescue organisation Orrca reported a 93% spike in hotline calls in March 2025, with 19 strandings and 28 entanglements recorded in New South Wales.
Dr Olaf Meynecke, a humpback researcher, noted that citizen scientists are now the main drivers of such research due to funding shortages. The study highlights the power of public contributions in documenting rare wildlife behaviours.
