Ultra-low tide makes 1km walk to island lighthouse possible

North Queensland's dramatic tidal variation is this year giving a rare opportunity to walk from the mainland to a lighthouse — 1 kilometre offshore.

Wading through water, the walkers set out from Bowen, about 200 kilometres north of Mackay, to reach the North Head Island lighthouse.

This year, the walk is only accessible for five days due to unusually low tides and the "new moon" lunar phase.

During this phase, the Moon is between the Earth and the Sun, and their gravity combines to pull the water out to sea in the same direction.

In 2025, there were no days when the water was below 0.2 metres, the recommended safe level.

While there was no official count, Bowen Tourism Association estimated hundreds of people trekked to the lighthouse over three days this week.

The association's Leanne Abernethy said the popular walk was also usually possible for two days a year in July or August.

"How many days the walk is possible depends on the tides," she said.

"It certainly does provide an economic boost to the town as people travel especially for the walk and often stay for a few days."

The six-sided lighthouse on North Head Island is one of Queensland's oldest surviving maritime structures.

It was originally built in 1866 to guide ships through the waters of Port Denison. It was decommissioned in 1985.

Coral and starfish part of the experience

Bowen resident Trudy Starkey does the walk most years when it is available and said seeing live coral, red starfish and sea slugs was part of the experience.

"I love the amount of people it brings to Bowen, and people are so respectful for the starfish and coral, which is something we don't see very often," Ms Starkey said.

Sisters Nakita and Ta-qusha Hegarty from Bowen made the trek to the lighthouse for the first time.

"We've been wanting to do it; we were always working and could never get over," Ta-qusha said.

The pair said despite sore legs and cold water, the view from the lighthouse and sea creatures they encountered along the way made it worthwhile.

"The beautiful scenery, the walk, everyone getting together … it's a good day for everyone," Nakita said.

'Key ecosystem'

CSIRO oceanographer Clothilde Langlais said tidal differences were also influenced by the Great Barrier Reef.

Dr Langlais studies tidal ecosystems and said the region from Mackay south to the Broad Sound strait had the biggest difference between high and low tide on the east coast of Australia.

Mackay's tidal range is about 6 metres, while areas of the Broad Sound strait have up to 9 metres of variation between low and high tide.

"The reef matrix is actually quite dense offshore, meaning the tide struggles to penetrate through," Dr Langlais said.

She said the tidal variation created mudflats that were home to crustaceans, migratory birds, and seagrasses, which played a crucial role in protecting the reef.

"They can stabilise the sediment and they're very good at sequestering carbon as well," she said.

"These mudflats are a very key ecosystem to protect the whole area."

Natural artwork

The region's extreme tides has fascinated photographer Jeff Jones since he moved to Mackay three decades ago.

In recent years, he has spent more time by the water, using an aerial camera to document unique patterns and streaks of colour in the tidal system.

"I was into the seascapes, landscapes, but being the creative type, I began to see more people's work with drones," he said.

"Every time I come out, even to the same place, the landscape is different according to where the winds have been coming from."

Mr Jones hoped his photos would help to preserve the history of the region, and to encourage others to protect its environment.

"I started to take pictures of things with that kind of thing in mind, about preserving what we have left," he said.