The Great Blue Hole
The Great Blue Hole is a giant underwater sinkhole which lies around 40 miles off the coast of Belize, near the center of the Lighthouse Reef. Given its name by British diver and author Ned Middleton, who was inspired by the Great Barrier Reef in Australia, the circular hole is approximately 1,043 feet wide and 407 feet deep.
As the largest natural formation of its kind in the world, the Great Blue Hole has been a huge draw for many marine explorers seeking to discover its mysteries.
A Mythical Underworld
A UNESCO world heritage site, the Great Blue Hole is one of the most interesting and mysterious formations of its kind. A popular diving spot, this deep black hole swallows the diver in complete darkness, making divers feel as if they are exploring a “mythical underworld.”
Divers can spot denizens, Pederson’s shrimp, groupers, angelfish, neon gobies, purple sea fans, and corals such as elkhorn and brain corals in the shallower parts of the area. But even more fascinating than the hole’s wildlife is the history and legends surrounding it…
Aura Of Mystery
Little was known about the Great Blue Hole for many centuries, and it retained an aura of mystery as to how it came to be and what could be hiding in its depths. Locals held many superstitious beliefs about what hid at the bottom, including tales of monsters hiding within.
In the late 1960s or early 1970s, members of a diving expedition from Caye Caulker claimed to have sighted a giant “sea serpent” in the hole while scuba diving, which of course added to the general sense of intrigue surrounding it. But nobody had yet penetrated its depths.
Jacques Cousteau Made It Famous
But thanks to advances in submarine technology, the mysterious blue hole would soon be explored just a couple of years later. In 1971, the famous French diver/explorer Jacques Cousteau, credited for the invention of scuba diving, brought his research boat, the Calypso, to explore the Great Blue Hole.
After broadcasting his voyage on his iconic television series, The Undersea World of Jacques Cousteau, the sinkhole was made world-famous. As the first explorer who attempted to plunge to its depths, Cousteau discovered some very important information…
Curious Rock Formations
Once Cousteau plunged to depths of about 145 ft, he was completely submerged in darkness. The oxygen levels were getting progressively lower, and the marine life gradually petered out until there was barely a living creature in sight.
That’s when Cousteau discovered that there were curious rock formations inside the giant hole. As it turns out, this was not simply a hole in the ocean floor. The rock formations were actually stalactites, which only form on dry land. That meant that the Great Blue Hole had once been a cave… above ground…
It Used To Be A Cave
The cave, which contains giant stalactites, dripstone sheets, and columns, was flooded by rising sea levels between 15,000 and 150,000 years ago, during previous ice ages. Seawater had filled the cave in four stages, leading to the formation of “terraces” and stalactites whose mineral composition contains information on the earth’s history during this period.
While Cousteau managed to discover quite a bit about the Blue Hole, he wasn’t able to reach its floor. The question of what was lurking deeper than 145 ft. remained a mystery… until now…
A Legacy Of Exploration
And it wasn’t just anyone who decided to breach the depths of the Great Blue Hole. It was Fabien Cousteau, the grandson of Jacques Cousteau himself. Having grown up aboard his famous grandfather’s expedition boats, Fabien grew up to follow in Jacques’ footsteps to become a marine explorer and conservationist in his own right.
And in November 2018, he set out to finish the “unfinished business” of his grandfather and find out what was at the bottom of the hole, once and for all. But he wouldn’t do it alone…
Richard Branson Joins The Mission
Fabien was joined by none other than world-famous billionaire Richard Branson. Branson, who rose to fame and fortune through growing his Virgin Records label into a business empire, is also a philanthropist with a particular interest in humanitarian and environmental issues, as well as a lover of extreme sports and adventure.
So it was only natural that he would join on this expedition to “get to the bottom” – in every sense of the word – of the Great Blue Hole.
Getting To The Bottom
Cousteau and Branson teamed up with Aquatica Submarines for the expedition, which included 20 dives conducted with the company’s Stingray 500 submarine led by Chief Pilot and Oceanographer Erika Bergman.
The expedition included a two-hour live broadcast on the Discovery Channel that had Branson and Cousteau descend into the depths of the Great Blue Hole. Fabien Cousteau had returned to the spot his grandfather had made famous with the technology of today, that would be able to descend the 400 feet to the bottom of the hole.
A Massive Wall Of Stalactites
The team set out on its mission to collect scientific data, including a complete topographic sonar scan of the hole. Branson recalled, “We traveled about 10 minutes in the submarine into the Blue Hole and then started edging down the wall of the hole.
The first thing we came across was a massive wall of giant stalactites, which were breathtakingly beautiful.” Some of these formations measure up to 12 meters or 40 feet in length. Most divers never get beyond this point, but now Branson, Cousteau, and Bergman were about to go deeper than anyone had before.
Submerged In Darkness
As the team approached the bottom, they approached a layer of toxic hydrogen sulfide at 300 feet, which submerged into total darkness. “You lose all of that Caribbean sunlight and it just turns completely black, and it’s totally anoxic down there with absolutely no life,” explained Bergman.
Luckily, they were accompanied by another submarine, the Anabel, which lit their way as they descended into pure darkness, while using sonar technology to map the topography of the hole. Thanks to its bright light, the team would make some even more fascinating discoveries…
When the team was almost at the bottom, Bergman spotted never-before-seen stalactites at a depth of around 407 feet. “That was pretty exciting, because they haven’t been mapped there before, they haven’t been discovered there before,” she recalled.
But that was only the first of many discoveries the team would make. When they reached the very bottom of the hole, they saw some mysterious, tiny circular tracks and markings in the sand. What could have caused these strange markings?
The answer lay in the toxic hydrogen sulfide layer and the lack of oxygen in the floor of the hole. Conchs had probably fallen down into the hole, and the tracks marked where they had tried to make their way back up the hill, only to slide down again to their deaths.
Imagining this scenario can be somewhat melancholy, but the number of conch shells that were found indicated a healthy conch population overall. As of yet, no “Blue Hole Monster” was anywhere to be found…
They Found Plastic
At that point, the team realized that no “ocean monster,” nor any living creature could possibly survive the lack of oxygen and sulfide in the hole. That is, at least not the kind of monster that lived in the popular imagination. But they did find something that is arguably more troubling and frightening than any legendary monster.
As they crept along the floor of the Great Blue Hole at a depth of over 410 feet, the ocean explorers were dismayed by what they found: plastic bottles…
The Real “Ocean Monsters”
Branson, Cousteau, and the team were distraught and dismayed. Plastic had reached the bottom of the biggest sinkhole on the planet, contaminating one of the world’s most incredible wonders. Branson posted on his blog soon afterward;
“As for the mythical monsters of the deep? Well, the real monsters facing the ocean are climate change—and plastic,” Branson wrote. “Sadly, we saw plastic bottles at the bottom of the hole, which is a real scourge of the ocean. We’ve all got to get rid of single-use plastic.”
8.3 Billion Tons
Unfortunately, it comes as no surprise that plastic was found in the Great Blue Hole – it is now a well-known fact that plastic is simply everywhere. Mass production of plastic started in the 1940s and ’50s, and studies found that around 8.3 billion tons of plastic had been made as of 2017 – the majority of which has been discarded.
Plastic has reached the most remote places on earth, from deep-sea sediments three miles below the surface of the ocean to Arctic sea ice and Swiss mountains.
They Made A Sonar Map
The main goal of the expedition was successful. As Bergman reported, “We did our complete 360 sonar map and that map is now almost complete,” she said. “It looks really cool, it’s this mesh-layered, sonar scan of the entire thousand-foot diameter hole.”
The mapping of this unique site, however, was done with a purpose: it was done in support of Ocean Unite, an organization that promotes ocean conservation that is campaigning to protect at least 30% of the ocean by 2030.
A Stark Reminder
It wasn’t only the plastic that caught the explorers’ attention. The Great Blue Hole, according to Branson, “…is proof of how oceans can rise quickly and catastrophically. Sea levels were once hundreds of feet lower. 10,000 years ago the sea level rose by about 300 feet when a lot of ice melted around the world.
At 300 feet down you could see the change in the rock where it used to be land and turned into sea. It was one of the starkest reminders of the danger of climate change I’ve ever seen.”
Combating Climate Change
Most of Richard Branson’s time is now spent building businesses that aim to make a positive difference in the world, and one of his main focuses has been combating environmental decline.
He recently proposed a new plan to combat climate change which he calls a Clean Energy Dividend, which would “tax” companies’ fossil fuel use and emissions, and use the money to invest in generating clean energy through wind farms and solar panels, and developing breakthrough technologies such as low carbon fuels.
A Beautiful World
Branson says, “Our generation has inherited an incredibly beautiful world from our parents and they from their parents. It is in our hands whether our children and their children inherit the same world. We must not be the generation responsible for irreversibly damaging the environment.”
Indeed, it is now becoming clear to the world that the main hurdle we face in the coming centuries is that against climate change, pollution, and the depletion of the planet’s natural resources.
Conserve The Oceans
So, was the epic journey to the bottom of the Great Blue Hole a success? President of Aquatica Submarines Harvey Fleming certainly thinks so.
“The Expedition’s successes really mean that we were able to show the magic of the Blue Hole to the world and reinforce the messages of all the Expedition members that we must continue to work diligently to conserve our world’s oceans for future generations.” The magic of this eerie underwater world certainly comes across – all the more reason to fight to preserve it.
A Brighter Future
Following the expedition, Fabien Cousteau was passionately driven to spread the message. “The environment and conservation is the only investment in our natural resource ‘bank account’ in the future well-being of our children. Without a healthy planet, there are no such things as healthy people.
So it behooves us to highlight the fact that we must take care of our planet, the way we do for ourselves and our family. If we are going to imagine a brighter future for ourselves,” he said.
Like Grandfather, Like Grandson
This echoes the sentiments of his legendary grandfather, Jacques, who saw the protection of oceans and nature as paramount to human survival.
“For most of history, man has had to fight nature to survive; in this century he is beginning to realize that, in order to survive, he must protect it.” By returning to the Blue Hole that his grandfather made famous, Fabien has drawn attention to his grandfather’s message which, 50 years later, is more relevant – and urgent – than ever.