As the polar vortex bore down on the United States in early February, we left our home in New York via an ice-encrusted front door. We were lucky enough to have tickets to Bonaire, a little island in the Caribbean Sea. Seven hours later, including a layover at Miami International Airport, the plane landed on a sunny, flat field rimmed with pipe organ cactuses and scraggly shrubs. Bonaire looks like Arizona, except for the azure waters in the distance. It also happens to be showing the rest of the world just how to save coral.

Bonaire is a true desert island. Tiny and crescent shaped, it is south of the hurricane belt, but right in the path of the trade winds, almost constant breezes from the east that push off rain.

The same winds brought the first

Dutch colonists and their slaves on sailing ships to this island in the 17th century. Their descendants still speak a unique Creole language, Papiamento, the vernacular of all native Bonaireans.

In a dying reef world, tiny Bonaire, population 19,405, is a success story, mainly thanks to the relative paucity of people, which has kept development at a minimum. Its reefs are also thriving because of a 40-year-old marine maintenance system, and a coral reef restoration effort, both of which are models for the rest of the Caribbean.

Our first morning on the island, eyes half-blinded like moles by the equatorial sunlight, we followed Ebby Jules, a muscular local dive master with two decades of reef experience, to his truck, dented from a recent fender bender on the island’s narrow roads. (Goats and the feral descendants of Nubian donkeys brought over by the colonialists are charming but significant traffic hazards, along with scooters and tourists on golf carts.) He steered us to our first snorkel spot across from the glittering pink and white salt “pans,” shallow lagoons of evaporating seawater once worked by slaves in brutal conditions, and now operated by the American agri-giant Cargill.

Weightless adventure

We paddled weightless on the surface as the water deepened to about 30 feet, and the white sand below disappeared into a navy void. Suddenly it was around us: hundreds of thousands of silvery fishes splitting into two great aisles, and reforming, moving as one, weaving parabolas up, down and under, millions of scales glinting sunlight. The effect was breathtaking, like being sucked into a tunnel of stars, or time-­traveling through the universe.

We lingered transfixed for 45 minutes until we felt cold and then clambered out. Back on the terrestrial plane, we were clumsy and felt our weight again and the itchy drying of the salt on our skin. We were hooked.

This is your brain on reef: Floating in warm salt water, colorful fish flitting in and out of view, the occasional sea turtle swimming up to have a look at you above a gold and yellow and green and white seafloor of corals slowly swaying. Weightless and warm, body evaporates and the mind becomes conscious of intimations of universal interconnectedness. The experience is as profoundly relaxing and peaceful as one can find without taking a pill or a shamanic herbal tea.

This natural wonder was born 3 million to 4 million years ago, when the Greater Caribbean became isolated from the Pacific Ocean after the closing of the Isthmus of Panama. It has since developed its own unique reef life, with about 65 species of hard corals and some 500 to 700 species of fish. Many of them are thriving along much of the 226 miles of Bonaire coastline, and can be experienced by anyone with a mask and fins.

On the map

Maps of the island show it rimmed with 62 numbered dive and snorkel sites, marked on the roadside with yellow painted rocks, with names like Andrea 1 and Andrea 2, Tori’s Reef and Jeannie’s Glory. Many sites are named after the various girlfriends of “Captain” Don Stewart, a California sailing hippie and party animal who wanted to be a pirate in the Caribbean and washed upon Bonaire in 1962 with a leaky boat. Stewart, who died on Bonaire a few years ago at the age of 94, was a self-taught diver who liked to hunt with a spear gun, until he repented killing and became an early evangelist for reef maintenance and restoration.

Stewart gets credit for dreaming up what became the Caribbean’s first and oldest marine park, Stinapa, which 40 years ago instituted rules limiting fishermen and divers. Among them: No more spearfishing. No more anchors. They built underwater moors for boats to tie up on. And each of the divers who come to Bonaire must take a one-day orientation course where they are reminded of a set of strict rules, not to trample corals, not to wear gloves or chemical sunscreen, to touch nothing, and never to drop anchor on the reef.

Bonaire is a leader in new efforts at reef restoration, along with a nongovernmental organization called Reef Renewal Bonaire, that in just a few years has grown and replanted some 20,000 staghorn corals in the water around the island. Corals are tiny soft creatures that survive on plankton and photosynthesis, and secrete calcium carbonate. They split and clone themselves one by one to eventually form large, curious looking underwater structures — brain coral, staghorn, elkhorn, fan, star and hundreds more shapes, depending on their species.

Coral reefs are essential to the health of the oceans and human life. But increasingly shoreline overdevelopment and warmer oceans are killing the corals. Once rare, coral bleaching now happens once every six years, leaving behind calcium skeletons where flora and fauna thrived.

Reef Renewal Bonaire is partly financed by local dive shops and it has successfully experimented with underwater “nurseries,” which are treelike and fiberglass, to grow new coral from tiny bits of living coral, to transplantable size. When the baby coral grows to about the size of a basketball, after about six months, volunteers and a few interns again transplant it onto the reef floor. Some 20,000 coral transplantations are thriving on reefs around Bonaire and more are being planted all the time.

Bonaire’s edge was once so dense with staghorn coral that divers and snorkelers had to fight their way through forests of it. The Reef Renewal coordinator and oceanographer Francesca Virdis has worked on Bonaire’s reef since 2008. In her 10 years on the island, she said she has witnessed increasingly unchecked development, which she believes is threatening the reef. The annual number of tourists has increased to 130,000 last year from 80,000 a few years ago, she said.

Besides Reef Renewal Bonaire, the Marine Park also rescues and replants corals in the path of any underwater pier or mooring construction. Large transplanted colonies are now thriving in areas away from cruise ship piers. The office monitors yearly for bleaching incidents, reports on mortality, and every two years, partners with Maine University, to do a round of complete coral monitoring.

Ramon de Leon Barrios, a Uruguayan-born oceanographer who ran Bonaire’s Marine Park for 11 years, said Bonaire’s success at maintaining a pristine reef proves that local community efforts can and do make a difference, even in times of environmental degradation.

“I want people to realize that there is hope,” he said. “You may never have been here, but the oceans are the lungs and kidneys of the planet, and without a healthy sea, we won’t make it. There is still time.”