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Under Greenland's ice: A mass grave of butchered whales
Beneath the frozen surface of eastern Greenland, underwater photographer Alex Dawson discovered a grim scene: the skeletal remains of approximately 20 minke whales, their bones trapped in shallow waters. Unlike natural whale falls that nourish deep-sea ecosystems, these carcasses were stripped by hunters, denying the ocean depths a vital source of sustenance.
The perilous dive
Dawson and his team embarked on a grueling journey to reach the dive site, traveling for an hour by snowmobile and foot through harsh Arctic conditions. Temperatures plummeted to -20°C (-4°F), and strong winds battered the group. Equipped with snowshoes, they navigated thin ice that gave way with each step, soaking their legs in near-freezing water.
Upon arrival, the team spent hours cutting a triangular hole through a meter-thick layer of ice to access the ocean below. Dawson, clad in a thick drysuit, was the first to descend into the frigid, pitch-black waters. Despite the protection, he described the cold as excruciating, likening it to his face "falling off."
Freediver Anna Von Boetticher followed, wearing only a 5mm wetsuit in the -2°C (28°F) water. Her exposure was limited to 45-second intervals before she needed to surface for air.
A troubling discovery
As Dawson's eyes adjusted to the darkness, he found himself surrounded by whale bones scattered across the seafloor at a depth of just 5 meters (16 feet). The sight was both striking and unsettling. "I started looking around, and I was like, 'This is so crazy. There are so many bones everywhere,'" he recalled.
His exploration was abruptly interrupted by the sound of cracking ice-a loud boom echoed through the water as the tide shifted. The pack ice, a drifting mass of frozen seawater, began to sink, threatening to seal the team's only exit. "If our hole were to compress, I thought, 'I'm screwed,'" Dawson said. Despite the danger, he pressed on, capturing the haunting image that later earned him the title of Underwater Photographer of the Year 2024.
The ecological role of whale falls
Whales, some of the largest animals to ever exist, play a crucial role in ocean ecosystems, even in death. When a whale dies naturally, its carcass sinks to the ocean floor, creating a "whale fall"-a nutrient-rich oasis that supports a diverse array of deep-sea life. According to Greg Rouse, curator of benthic invertebrates at Scripps Institution of Oceanography, these carcasses can sustain up to 407 species, fundamentally contributing to deep-sea biodiversity.
The decomposition process begins with surface scavengers like seabirds and sharks feeding on the floating carcass. As the body sinks, it passes through multiple ocean zones, eventually reaching the abyssal plain. The deepest recorded whale fall, an Antarctic minke whale, was found at a depth of 4,204 meters (13,793 feet), where it had supported a thriving ecosystem for nearly a decade.
Once on the ocean floor, the carcass becomes a hub of activity. Scavengers like hagfish, sleeper sharks, and amphipods strip the flesh, while bone-eating worms (Osedax) consume the fats and collagen within the bones. The decomposition process releases lipids and sulfur, fostering chemosynthetic bacteria that support species typically found in hydrothermal vents and cold seeps.
Human impact on whale falls
Industrial whaling over the past century has drastically reduced whale populations, with nearly three million whales killed-a cull described as the "largest in terms of biomass in human history" by a Nature report. The remains of these whales were often abandoned in shallow waters or on shores, disrupting the natural cycle of whale falls.
In eastern Greenland, subsistence hunting remains a cultural practice. The International Whaling Commission (IWC) notes that indigenous communities in Tasiilaq, a town of 2,000 people, rely on marine resources due to the region's limited agricultural potential. Hunters drag their catch ashore to the "flenseplassen" or skinning grounds, where families strip the carcasses of blubber, meat, and bone. The tide then carries the skeletons back into the water, where they remain trapped in the shallows.
Minke whales, though abundant and found worldwide, are not exempt from this practice. In East Greenland, an average of nine minke whales are killed annually. While the number may seem small, experts warn that even these catches can deprive deep-sea ecosystems of vital nutrients, potentially leading to the extinction of species before they are even discovered.
A loss for deep-sea biodiversity
"We're still in an era of very low whale numbers," Rouse said. "So, there's probably a lot less whale skeletons on the seafloor than there used to be." While thriving whale fall ecosystems still exist, the catastrophic decline in whale populations raises concerns about the loss of undiscovered species and the long-term impact on deep-sea biodiversity.
The shallow graves in Greenland's waters serve as a stark reminder of the delicate balance between human practices and the health of our oceans. As Dawson's photographs reveal, the consequences of disrupting this balance extend far beyond the surface.
