Exploring Australia's forgotten territory: The Coral Sea Marine Park

Few may have heard of the Coral Sea Marine Park, but for adventurer and author Peter Sayre, its vast waters and remote reefs have been both a home and a lifelong obsession.

Bordering the eastern edge of the Great Barrier Reef, the Coral Sea Marine Park stretches from Cape York in the north to Bundaberg in the south, covering nearly one million square kilometers of open ocean, coral atolls, and uninhabited islands.

This vast expanse of open ocean, coral atolls, and uninhabited islands remains one of Australia’s most remote and least explored marine environments.

Peter Sayre is among the first to extensively explore these waters. Alongside his wife Michelle and their boat The Phoenix, he has navigated and named countless dive sites. 

His decades of exploration led to Australia’s Coral Sea Islands & Marine Park, a comprehensive guide to this untouched region.

“Exploration in Australia’s Coral Sea has been almost nonexistent in modern times. Navigating these waters is no easy feat,” Peter said.

While Osprey Reef, about 120 miles east of Lizard Island, is one of the better-known sites, venturing beyond presents even greater challenges.

For Peter, that challenge is the ultimate reward. “The adventure, the unknown, that’s what keeps me going.

“I haven’t added up how many weeks, months, or years I’ve spent in the Coral Sea, but suffice it to say; a lot.”

With visibility often exceeding 50 meters, sometimes up to 70, the underwater landscapes are breathtaking. “You can lean over the side of the boat, look straight down, and feel like you’re in the air.”

The area also boasts vast underwater cave systems, some large enough to fit a bus. But for Peter, the real excitement lies in the unknown. 

When asked about his favourite discovery, he always answers, “It’s the one I haven’t found yet.”

Shipwrecks, particularly from the 17th and 18th centuries, hold a special fascination for him. “We know where the marked ones are, but it’s the undiscovered ones that intrigue me. When looking for old ship wrecks “you don’t know what you don’t know until you know it” 

Protecting the Coral Sea

Peter has seen the Coral Sea change over the years, with some reefs thriving while others have declined. 

“One reef, Magdalena Island, used to be spectacular. When I returned, much of it had deteriorated,” he recalls.

To understand these changes, he turned to historical records, researching maritime charts, ship logs, and scientific reports. 

“I don’t just look for shipwrecks, I study how the Great Barrier Reef and Coral Sea Islands have changed over centuries,” he said.

Having worked with National Geographic, the Australian Institute of Marine Science, and Queensland University, Peter has witnessed the reef’s natural cycles firsthand. 

A Queensland University study revealed that coral formations have undergone 5,000 years of growth and decline, challenging the misconception that all damage is recent.

While climate change is a major factor, the research shows that reefs naturally go through cycles of growth and decline, reinforcing the importance of conservation efforts to help reefs recover.

However, he believes overregulation has also had unintended consequences.

“When the Coral Sea was declared a marine park in 2013, it made operations difficult for businesses like mine,” he said. 

“I used to run spearfishing charters with some of the best in the world. Now, with so many restrictions, fewer people go out, and that actually makes illegal poaching easier.”

He recalls foreign fishing boats targeting sea cucumbers in the Coral Sea, choosing these remote waters over the closely monitored Great Barrier Reef. “They knew there weren’t enough people watching,” he said

“Conservation starts with responsible practices; choosing anchor points carefully, ensuring no waste is left behind, and respecting local fishing traditions.