Greenland Shark

Fascinating facts about the Greenland Shark

• A Greenland shark doesn't reach sexual maturity until around age 150 — meaning it spends more time as a teenager than most humans live. Scientists discovered this by studying radioactive carbon in their eye lenses from nuclear weapons tests, which allowed them to count growth rings and reveal lifespans stretching past 400 years. They may be the longest-lived vertebrate on Earth, yet they move so slowly through the water (1 km/h) that their prey — seals — should easily outswim them.
• Greenland sharks are nearly blind. A copepod, a parasite the size of a sesame seed, embeds itself in each shark's cornea, eating away at the tissue and leaving a scar. Scientists believe up to 97% of Greenland sharks live with this infection, yet they hunt successfully in waters so dark that light never reaches them anyway — they hunt by smell and sensing electric fields, not sight.
• Half of a Greenland shark's diet is rotting seal blubber scraped from the ocean floor. They also hunt living seals three times their own size by approaching so slowly the seal doesn't notice until the shark's mouth opens. Their stomach can expand to hold prey weighing up to 30% of their body weight, and they digest so slowly that some scientists think they may only eat once every few years.
• Greenland sharks carry toxic levels of urea and TMAO — chemicals that would poison most animals — but their kidneys and tissues have evolved to tolerate them without damage. This same poison is why their meat is inedible to humans unless buried and fermented for months, a process called *hákarl* by Icelanders. One Viking explorer called eating it 'the worst food I've ever tasted.'
• Climate change is pushing Greenland sharks out of their comfort zone faster than they can move. These sharks live at depths of 200–2,000 metres where water temperatures are dropping as Arctic currents shift. At speeds of 1 km/h, a shark trying to follow cooler water would need to migrate nearly 900 km — a journey that could take decades, yet their body clock and metabolism are locked to the cold they've known for centuries.

At a glance

About the Greenland Shark

In the dark, icy waters of the Arctic, the Greenland Shark glides with a slow, deliberate pace, its massive, torpedo-shaped body undulating through the sea with a hypnotic rhythm. As it moves, its small, beady eyes seem to hold a profound wisdom, as if the secrets of the deep are etched into its ancient, weathered skin. With a lifespan of up to 400 years, this venerable creature has witnessed the passage of centuries, its remarkable endurance a testament to the resilience of life in the harshest of environments.

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