One of the world's greatest conservation success stories is creating a new challenge on the Great Barrier Reef - how tens of thousands of humpback whales and millions of people safely share the same waters.
Humpbacks are again putting on their spectacular aerial ballet along Queensland's coast, breaching, tail-slapping, breeding and nursing calves as they migrate through the Great Barrier Reef Marine Park.
But the extraordinary recovery from the brink of extinction is bringing whales and people together more often, with remarkable close encounters increasingly captured and shared online.
New Reef Authority compliance data reveals possible offences involving people unlawfully swimming or interacting with whales increased six-fold last season, from two incidents reported by members of the public in 2024 to 12 incidents reported in 2025.
Reef Authority Chief Scientist Dr Roger Beeden said the resurgence of the east coast population posed a fresh test for reef management to make sure everyone on the Reef understands the whale distance rules.
"We've gone from an estimated 500 humpbacks surviving industrial whaling six decades ago,'' Dr Beeden said,
"Today we're seeing about 50,000 migrating along Australia's east coast - it is one of the great wildlife recovery stories," Dr Beeden said.
"But success brings a new challenge. More whales are now moving through busy waters used by commercial shipping, tourism vessels, yachts, tenders, recreational boats and visitors.
"More megafauna and more people sharing the Marine Park means we need to find the right balance between experiencing these extraordinary animals and giving them the space they need."
Research into the rapidly recovering east Australian humpback whales has suggested the population may be approaching a natural turning point with estimates it may tip as many as 60,000 individuals.
Population modelling has previously identified 2026 as a potential period in which abundance could peak, raising important questions about carrying capacity and what happens as the population reaches the limits of its recovery.
Dr Beeden said the whales were also a spectacular reminder that the Great Barrier Reef was much more than coral.
"When a 30 or 40-tonne whale launches itself out of the water, you are witnessing perhaps the most visible expression of the extraordinary biodiversity this Marine Park supports," he said.
"Reef resilience is about the whole interconnected ecosystem - coral reefs, seagrass meadows, islands and the extraordinary diversity of animals that depend on them."
From the southern Reef through the Whitsundays to tropical north Queensland, the migration brings environmental, social and economic benefits, supporting regional tourism while giving residents and visitors the opportunity to experience one of the world's great wildlife spectacles.
In 2025, 408,000 domestic overnight visitors and 230,000 domestic day-trippers went whale watching in Queensland, contributing almost $670 million to Queensland's economy. Australia's whale watching industry also attracted 310,000 international visitors in 2025.
"The return of the humpback shows what conservation can achieve," Dr Beeden said.
"Our challenge now is learning how to coexist with that success."
Fascinating humpback whale facts
- Humpback whales mate face to face, locking into a 'hug' with their 5m long flippers.
- Female humpback whales typically begin breeding from 5-10 years old and do not have a defined menopause or breeding retirement.
- Female humpback whales have a gestational period of 11-12 months and give birth once every 2-3 years to a single live calf, fluke (tail) first.
- The mother's milk is the consistency of toothpaste, and the mother can produce up to 600L of milk per day.
- Male humpback whales, the most vocal and acrobatic of all the whales, perform complex soulful song patterns that can travel underwater for up to 50 kilometres.
- Humpback whales undertake an epic migration of up to 10,000km from Antarctica to the warmer breeding and calving grounds of the Great Barrier Reef.
- Humpback whales grow between 12-15 metres in length and can weigh an enormous 40 tonnes. Females are larger than males.
