While snorkelling in Arctic waters, Birgit-Cathrin Duval forgets how cold the water is as she sings with the Beluga whales in an undersea duet.

So much water, so much sky. Just as Canada is huge, Hudson Bay is enormous.

Churchill, on the other hand, is a small settlement in the far north of the province of Manitoba – a tiny speck under a vast azure sky and the clear turquoise water of Hudson Bay.

But the colours, so reminiscent of palm-filled lagoons, are deceptive. The water temperature in the Bay can dip below freezing and only reaches a high of 8-9°C, even during summer – pack ice is visible on the horizon.

I am sitting in a Zodiac, stuffed into a thick neoprene suit which is supposed to protect me from the cold.

Seven millimetres will separate my skin from the icy water of Hudson Bay apparently, and I’m skeptical.

The suits are so tight the staff had to help pour me into the suit in the wooden Sea North Tours hut back at the harbour, and the protective suit clings to my skin like tough rubber.

Jump right in…

Now we are on the water, concentrated and excited, imagining we’re doing a good impression of Greenpeace activists on the high seas. No one speaks, but everyone knows what is going through the others’ heads: “Do I really want to get into the water?" and “Will I go into shock if I jump in?"

These totally rational thoughts are interrupted as we spy the ivory-coloured bodies of a pod of beluga whales. They glide majestically through the water in groups of three and five.

During summer more than three thousand of these three-to-six-metre-long whales swarm to the warmer waters of the Churchill River to give birth to their young, and that makes the Churchill belugas the world’s largest accessible population – as we can now see.

Due to their unusual, melon-shaped heads, they are not as elegant as dolphins, but are just as curious and playful. They are called ‘canaries of the north’ because their calls sound like the twittering of birds.

They’ll sing to you…

Our Sea North Tours guide steers the boat from the Churchill River to the clearer water of Hudson Bay. There he stops the boat and turns the motor off.

And then we can hear them: a high-pitched whistling and chirping emerges from the depths. Bubbles rise, and we see their elegant white backs – they are so close, and then they dive away from the boat.

Should I really jump? How will they react? I hesitate. Other whales approach the boat, whistling and chirping all the while. I jump in with a heavy splash, and land in the sparkling green water.

For a moment, I feel nothing. Then the cold of Hudson Bay strikes me with the force of an electric shock. Adrenaline courses through my body – it’s an extraordinary feeling. I feel more alive than I have in a long time and completely forget the cold. Like a plump seal, I move through the water in my neoprene suit, because now I want to see the belugas and sing with them – a duet, perhaps, or even an aquatic quartet.

I stare through the green water through my mask. How deep is it here? What if a polar bear swims through the bay and tries to swallow me, mistaking me for a seal? Best not to think about it. I breathe deeply through the snorkel and press my lips together. Humming, I imitate the call of the belugas. I wonder if they can hear me.

They must – their calls are growing louder, like someone trying to find a station on an old transistor radio, and I get goosebumps from the excitement. But where are they? I flinch. Something jellyfish-like swims directly in front of my mask and, through the water, I hear the others whooping. Apparently the whales prefer tenor voices, because I see neither flukes nor fins. I attempt to switch from high to low tones, the lowest that my lungs can produce, and then they start to come to me!

They’ll come and hang out with you…

I see their white backs between the waves as they head straight for me. I duck my head underwater and straighten my mask.

A large whale swims directly underneath me. When he discovers me, he turns onto his back and eyes me curiously. I must look strange to him in my black rubber suit and mask. I wonder if he enjoyed my song. His wide mouth seems to smile at me and I want to touch him, but when I extend my hand, he disappears into the green depths.

Others come, glide alongside me, turn their heads toward me – they are gentle giants, circumnavigating me with care.

Despite their bulky heady and massive bodies, they float through the water like graceful nymphs. I am surrounded by chirps and peeps, as if we were singing in hymns in an underwater choir.

Belugas are such funny creatures. Am I imagining it, or are they smiling at me? Maybe I’m singing off-key. At any rate, I hum and chuckle out of pure joy. This unusual encounter with these incredible Arctic creatures has been exhilarating.

As I surface, I laugh, shouting with delight. Not even the icy water sloshing around in my mouth can put a damper on my feelings.

I shiver as I climb into the boat with the others – perhaps from the cold that I had completely forgotten, but more likely from happiness at the most extraordinary encounter of my life.

Travel information

Churchill is in the province of Manitoba and can only be reached by train or by air.

The Great Canadian Travel Company offers tours in Churchill with the six-day Beluga Encounter.

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