Hope on the Great Barrier Reef

"Wow, check out this little guy!"

I'm sitting on the stern of a solar-powered catamaran near Opal Reef, about 30 miles off the coast of Far North Queensland, preparing to jump into the Coral Sea. My husband and I are nearing the end of a three-week adventure through Australia, a trip that has included so many magical moments that it's felt, at times, like fiction: throwing back fresh oysters with old friends in Melbourne, taking in a show at the Sydney Opera House, hiking through paperbark forests in Kakadu National Park.

And, incredibly, it's not over yet. We're here on our last day down under to snorkel on the Great Barrier Reef.

In the water next to me is marine biologist Kate Slaughter, one of the guides on our tour with Wavelength Reef Cruises. She's holding a hand toward me as I struggle to squish my feet into my rubber fins. On the tip of her gloved finger is the teeniest crab I've ever seen, its little greenish shell about the size of a fruit fly. Behind her goggles, Slaughter's eyes are lit up in wonder. I watch as she turns her hand over and over, marveling at her new friend scuttling around on her palm. Oh, I realize. She's just as excited as I am.

My hair isn't even wet yet. Soon, I'll witness the whole world churning beneath us, the anemone and cuttlefish and, yes, the reef sharks, and dozens of other weird and wild creatures, arguably far more interesting than this practically microscopic crustacean.

Still, weeks later, this will be one of my most vivid memories of the day: this young scientist holding her hand out to me, utterly dazzled by the little life she's stumbled upon.

The Heart of the Ocean

That exchange between science and tourism is part of what makes Wavelength special. It's the only reef tour company in Queensland that's owned and operated by local marine biologists - which means that when they're not showing people like me around the outer Great Barrier Reef (GBR), they're taking an active role in conservation and reef restoration.

"We do a lot of research on the boat," Slaughter tells me. "We have weekly surveys to keep an eye on how things are changing in the short term, and more in-depth quarterly surveys."

That work is aimed at improving coral health, which has been suffering for decades due to warming ocean temperatures and acidification. The Global Coral Reef Monitoring Network reports that between 2009 and 2018 we lost approximately 14 percent of the world's coral - an amount greater than all the living coral in Australia's reefs. In 2017, the United Nations estimated that 70 percent of reefs around the world were under threat.

These numbers represent much more than the loss of a beautiful tourist destination. Coral reefs are a vital indicator of overall ocean health - and the backbone of one of the most biodiverse ecosystems on Earth.

The GBR is the world's largest living structure and the only organism that's visible from space. Though coral reefs cover less than 1 percent of the sea floor, they're home to nearly a quarter of all marine life, providing food, shelter, and breeding grounds for more than a million ocean species.

When I finally press my face under­water, it's as though I can see them all at once: the parrotfish crunching coral between their jaws, the gobies sifting through the sand for critters to eat, the striped wrasses plucking parasites from the backs of sleepy-looking groupers. The sound is ­unbelievable - like a whole city bustling along its morning commute.

I swim through a school of blue damselfish; they sparkle around me like jewels. I spend several minutes floating above a giant clam the size of my office desk back home, watching the pulse of its body as it breathes in and out, like a heartbeat at the bottom of the sea.

A Growing Threat

What we think of as coral is actually limestone, a protective exoskeleton built by the tiny invertebrates that live inside. These coral polyps contain millions of photosynthetic algal cells that use light to provide the coral with oxygen and nutrients. The algae also produce the coral's beautiful pigments, which vary depending on the spectrum and intensity of its light exposure.

When coral is stressed - by rising water temperatures, too much sunlight, or other changes in the ocean environment - it ejects its algal cells, losing both its color and its primary food source. Large-scale "bleaching" was once relatively rare, but the U.S. National Oceanic and Atmospheric Association reported in May 2025 that nearly 84 percent of the world's reefs had experienced heat stress since early 2023, accounting for the most widespread global bleaching event on record. It's the fourth of its kind since 1998.

Slaughter first visited the GBR in the winter of 2016, following a particularly severe bleaching event throughout the northern section. "More than 80 percent of the reef experienced some degree of bleaching that summer, and I was swimming in the aftermath," she says. "I was so excited to see the reef for the first time, and it was beautiful, but it was quite shocking to see it in that state."

Corals have shown an incredible ability to repopulate and rebuild, she tells me, but they're in a vulnerable ­position. As ocean temperatures continue to rise, the reef has less time to recover between bleaching events, putting the health of the entire ecosystem at risk.

Planting Hope

Despite these grave statistics, ­Slaughter says, there's a lot of optimism in daily life on the GBR, where she and her colleagues are taking a hands-on approach to reef restoration, which they refer to as "assisted recovery."

Our second stop of the day includes the nurseries on Opal Reef, which Wavelength grows in partnership with the University of Technology Sydney. This partnership is part of the Coral Nurture Program ­cofounded by Wavelength in 2018.

When corals break off from the reef due to storm or wave damage, they typically die in the sand. When they don't, Slaughter and her colleagues try to capture and rehabilitate them at these nursery sites, which are open structures with lots of water flow to maximize coral growth.

"It's just a middle ground for the corals to stay," she explains. "And like a plant nursery, you can take cuttings from them." They take these cuttings to bare spots on the reef and effectively replant them, using stainless-steel clips that Wavelength designed.

Over lunch on the boat, ­Slaughter holds up a coral clip for our group to see. It's a simple tool, like a nail with a spring-loaded clamp on one side. But in its simplicity lies its brilliance: The clips require few additional tools and little training to use, and they represent a minimally invasive planting method that supports the reef's natural ability to heal itself.

Over the last few years, the Coral Nurture Program has planted more than 100,000 coral fragments back onto the reef.

"We work alongside researchers at the University of Technology Sydney to ensure that we are using the most-effective methods possible," Slaughter explains. "They've found that we have an 80 to 85 percent success rate, which is very strong. We would have been happy with 10."

This is not simply about beautification, she tells me. The more coral cover and biodiversity a site has, the more resilient it will be to threats like rising ocean temperatures. It also means those corals can reproduce along with the rest of the reef.

Coral colonies typically spawn only once a year as the full moon rises, a nighttime phenomenon that ­Slaughter describes as something "like an upside-down snowstorm." She and her colleagues have watched the corals that they personally planted onto the reef release all their reproductive cells into the water to be fertilized, eventually landing back on the reef to form new coral colonies.

"It's the most profoundly moving experience I've ever had," she says. "It means so much to know that we are assisting Mother Nature to maximize her perfect processes in the simplest way possible."

A Yard Worth Tending

I took a double dose of nausea medication before we left the marina, certain I'd be seasick on the water, but I didn't need it. We're here on what the crew calls a "diamond day," a synchrony of conditions that make for ideal snorkeling: low winds, minimal swell, plenty of sunshine for high visibility. My husband, who researched the weather and tidal patterns for weeks before selecting this day for our reef tour, is beside himself with glee.

"Did you see that blacktip?" he shouts to me on our final stop, a note of incredulity in his voice. He makes the sign the crew taught us for shark, one hand above his head like a dorsal fin. I've never seen him seem so much like the boy he once was, with a library full of books about the ocean and an encyclopedic knowledge of saltwater fish.

My vision blurs; I've been crying into my snorkel mask. I can't believe how much life is teeming around us, how vibrant and real it all is. And how vulnerable.

Before we say goodbye, Slaughter tells me that she's returned to those sites on the GBR that she first saw in 2016 - the bleached corals that ­inspired her career in marine biology - and some of them have bounced back. It's not linear, she emphasizes, and much of the reef continues to struggle.

"Still," she says, "I like to think the work we're doing in our own backyard is helping on a small scale."

The only way to save the reef is by reducing our reliance on fossil fuels and lowering our carbon emissions. Until then, ecologically sustainable tourism organizations like Wavelength can work to maintain these sites so they're worth visiting - which funds more research and conservation efforts.

"That collaboration between science and tourism is really important," Slaughter says. "It makes sense to work together because we have the same goal. We all want to see the reef flourish."