'There are so many bones everywhere': The whale graveyards that transform the deep sea

A photographer captured this extraordinary site where whales' bodies lie in the shallows. Had they died naturally, their bodies would usually be scattered across the ocean. These images tell the story of a deep-sea denied of vital sustenance, and entire ecosystems that will never come to be.

In eastern Greenland, Alex Dawson slipped into the ocean through a hole cut into the pack ice. He sank into the darkness below and – just a few metres down – he found a mass grave of butchered minke whales.

It took an hour of travelling to get to the dive site, by foot and by snowmobile. The air was -20C (-4F), and the team battered by strong winds. "We had a lot of gear," says Dawson, an acclaimed underwater photographer. "We were six scuba divers, with six divers' gear. There were cameras, there was food and all kinds of supplies for the day – safety equipment, ice drills…" The equipment was piled on a sledge and pulled by a snowmobile while the team walked on foot. "When you walked, if you didn't have snowshoes on you stepped through the thin layer of ice, and you got into water almost to your knees – every step," says Dawson.

"Once we got there it took hours to make the hole," he continues. Their way into the ocean beneath the ice was a small triangle-shaped hole cut by hand through about a metre (3ft) of ice. "We tried to clear out as much of the slush from the hole as possible," he says. Then, Dawson – in his thick drysuit, hood and gloves – was first to enter the water.

The site Dawson eventually found below the waves was not only striking, but troubling. In life whales transform their environment, and in death too they play an outsized role on their ecosystems. And here in eastern Greenland, bones that would naturally have fallen to the deep ocean floor instead lie trapped in the shallows.

Despite the protection of his drysuit, "I felt like my face was falling off", he says. "It was so extremely cold."

Anna Von Boetticher, who Dawson was to photograph swimming amongst the whale bones, followed him into the ocean. The competitive freediver wore just a 5mm wetsuit to protect her for from the -2C (28F) water. At this temperature she could only last up to 45 seconds before needing to surface for air.

Dawson, attached to a safety rope, dove straight down away from the daylight. This is when the fear began to creep in, he says. When you first enter the water through the hole, "you see nothing. It's just the black abyss below you. You feel like all these creatures are lying there [in the deep] looking up at you."

When he reached the seafloor, "I just lay there breathing," he says, as he waited for his eyes adjust to the darkness.

After a short while, his vision became clearer. "I started looking around, and I was like, 'This is so crazy. There are so many bones everywhere.'"

There, at around just 5m (16ft) depth – bathed in the blue light of their icy tomb – lay the remains of around 20 minke whales.

Dawson was just beginning to relax when he heard a loud "boom". "It sounded like somebody was blowing dynamite underwater. Then I heard a second boom. That's when I realised that this was the tide starting to move, and the ice cracking."

Diving under pack ice is one of the most hazardous kinds of diving. The currents could carry you away under the "endless pack ice", says Dawson, "and you'd be gone forever". Pack ice is made up of fragments of frozen seawater that are squeezed together, becoming a large mass of floating ice that covers the sea surface and drifts with the winds and ocean currents. 

"The tide was going out, which meant the ice was sinking. If our hole were to compress, I thought, 'I'm screwed' – because there was only one hole. It would take [the team above the ice], well over an hour to make a second hole if they were trying to save........

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