Rogers – grizzled beard, piercing gaze, lots of laugh lines – has been within eavesdropping range of icebergs for 22 years as owner of Iceberg Quest Ocean Tours, based in St. John’s. But his fascination with these giant chips of glacier began when he was a boy, growing up in Twillingate, an island off the island. As a fifth-generation seafarer, his childhood was filled with tales of oceanic exploits and Arctic explorers, like Bob Bartlett from Brigus, N.L., who survived 12 shipwrecks. Rogers’ father and grandfather were both ship captains, and fireside conversations revolved around navigating fierce storms and mammoth bergs.

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“The most joyous time was spring,” says Rogers, “when I’d go down on the headlands and watch for icebergs. In the evening, you’d see one drifting along what people now call Iceberg Alley, then you’d get up the next morning and it would be gone. But it always stayed with me, the beauty and magnitude of the ice.”

Rogers says he was destined to make his life on the water, sharing his enduring awe for these icy monoliths from the north with visitors from all over the world. The bergs are as big a draw as the thousands of humpback whales that also return each spring to feed on caplin and krill – spotting whales is often an added bonus when you’re out chasing icebergs.

Inevitably, there are questions about the Titanic. From the helm of the Capo de Espera, Rogers good-naturedly fields them all. The most oft-posed query, “How big was the iceberg that sank it?” makes him chuckle. “The people on board probably didn’t take much time to think about that. But an iceberg doesn’t have to be very big to cause a lot of trouble.” Large bits break off, causing the water to roil (“When an iceberg collapses, you’re looking at, say, 60 tonnes of ice tumbling down from around 100 feet in the air.”) and, of course, bits also break off from the bottom (“When something the size of a house bobs up 500 feet away from you without warning, that gives you a respect for how dangerous they can be.”).

Rogers is a fan of foggy days, when he’s the only one who knows there’s a berg off the bow until, suddenly, he stops the boat – and a massive mountain of ice is illuminated in the fog. “The reactions I’ve witnessed run from hysterical laughter to tears. There’s a mystery and a wonderment about these ancient pieces of ice, and every one of them is different.”

There is also a niggling, climate-change-fuelled worry that we won’t be able to witness their incredible journeys forever. Iceberg-calving from glaciers in Greenland is increasing, depleting the Arctic’s ice sheet, while a new study from Australian researchers shows icebergs are melting faster than we thought. Scientists are keeping a close watch.

Stephen Bruneau, an associate professor in the Faculty of Engineering and Applied Science at Memorial University of Newfoundland, isn’t worried about iceberg extinction in the immediate future. “There is still a lot of ice in Greenland, and a lot of snow falling on it.” He adds that it’s hard to know exactly how climate change is altering the arrival of icebergs off Canada’s east coast when so many other variables affect how many appear from year to year, including ocean currents and wind direction.

Like Rogers, Bruneau inherited a fascination with icebergs from his father, a cold-ocean engineer who was on the world’s first iceberg-towing expedition, designed to make oil and gas exploration safer by redirecting troublesome bergs on less dangerous trajectories. Bruneau became an ice scientist himself, and the annual anticipation has yet to wear off. “The first iceberg of the year is always a thrill – even if you’ve seen thousands, there is still a flutter of excitement.”

Bruneau cemented his fate as an iceberg expert when, frustrated by an inaccurate news story about them, he wrote a letter to the local newspaper, which lead to a pamphlet, which lead to a guidebook. He has a few favourite iceberg moments, most of all witnessing one calve or roll. “The cracking sounds like cannon fire and the movements appear to be in slow motion. By the time it’s over, an iceberg can go from a medieval castle-like object to a blanket of rubble and brash, spreading out in all directions.”

To experience a berg’s final moments, you need to visit Newfoundland and Labrador, says Rogers. “We are one of the last accessible frontiers for viewing icebergs.” He sees himself as a steward of the ocean, like Bruneau, sharing a knowledge and appreciation for a phenomenon that, like so many things in nature, is something of a marvel. On board any of his five vessels, guests are invited to enjoy a tipple made from pure iceberg water, from gin to screech (“There’s no fit tour boat in Newfoundland that don’t have a bottle of screech on board.”), poured over bits of iceberg fished straight from the sea. “Where else in the world can you both see and taste something prehistoric, then walk away and talk about it afterward?”

Icebergs by the numbers