For wildlife photographer Paul Nicklen, the elusive narwhals of the North Atlantic did more than inspire thoughts of unicorns. Having grown up alongside the Inuit of Canada's Baffin Island, Nicklen developed his curiosity and appreciation of narwhals early on  an appreciation that stuck with him as his career took him around the world. For 12 years, he returned home with one goal in mind: to capture an underwater photo of a male narwhal. For Nicklen, the narwhal was his unicorn. 

Narwhal Group Aerial Closer 2015 03 10
"Can you imagine: I’m lying on the sea ice, I’ve been in the water for 2 hours photographing narwhals, well, trying to photograph narwhals underwater which is next to impossible. I’m freezing, I’m hypothermic, I can’t move." Image: Paul Nicklen/National Geographic. Used with permission

"They're very shy," he recalls of his lengthy quest to photograph these alien-like creatures. "They have a sensitive nature and excellent echolocation. You can see hundreds passing by the ice edge, but when you slip into the water, you may never see one." 

The tusked whales only return to Baffin Island as spring temperatures cause channel-like splinters (or 'leads') in the sea ice, so actually encountering one often means waiting out stretches of complete darkness, intense snowfall and temperatures reaching a bone-chilling -40°F. 

Hundreds of hours diving and snorkelling in polar waters finally paid off when in the spring of 2007, Nicklen found himself in the middle of a narwhal mating dance – the encounter he'd always dreamed of. "I had been in the 29° F (-1.7° C) water for a couple of hours, and I was so freezing that my legs and arms were cramping up. I couldn’t feel my lips around my snorkel anymore, so I just stared into the black 2,000 ft (600 m) abyss trying not to think about [it]. Then, out of the corner of my eye, I noticed something bright travelling through the murky water. I turned my head, and there they were: several male narwhals, swimming in beautiful formation. I put my frozen finger on the shutter and, as I was about to take the picture, the narwhal closest to me let out a stream of bubbles. [It was] the most incredible moment."

Nicklen hopes his work will help spread the message about the importance of preserving this vast, white landscape – and the incredible animals that lurk beneath its surface. 

Narhwal Group Close 2015 03 10
Skilled swordsmen. A group of males gather in an ice holeImage: Paul Nicklen/National Geographic. Used with permission
Narwhal Duel 2015 03 10
At its peak during the middle ages, narwhal ivory fetched twice its weight in gold. Image: Paul Nicklen/National Geographic. Used with permission
Narwhal Group Aerial 2015 03 10
Image: Paul Nicklen/National Geographic. Used with permission
Narwhal Group Ice Aerial 2015 03 10
"If we loose sea ice in the Arctic, we stand to impact an entire ecosystem. This is the tragedy and loss we face" Image: Paul Nicklen/National Geographic. Used with permission

As if photographing his unicorn wasn't enough, the experience gave way to another animal encounter that Nicklen will remember for the rest of his life: coming face-to-face with a 200-year-old bowhead whale.

You can view more of the amazing series here.

Top header image: Paul Nicklen/Used with permission