King Crab

Fascinating facts about the King Crab

• A king crab's leg span can stretch nearly 2 metres across—longer than a tall human is high—yet the animal itself weighs up to 6 kilograms. All that reach comes from legs built like hydraulic pistons, packed with muscles that let them sprint across the seafloor at surprising speed. This design lets them hunt across vast stretches of ocean floor where food is scattered and sparse.
• King crabs don't have bones or a backbone, but they do have an exoskeleton—a full-body suit of armour they must shed to grow. The moult takes hours and leaves them soft and defenceless, so they hide in crevices until their new shell hardens. A single crab might shed its shell 20 times in its lifetime, each time emerging slightly larger but completely vulnerable.
• Their blood is blue, not red. King crabs use a copper-based molecule called haemocyanin to carry oxygen through their body, rather than the iron-based haemoglobin that colours human blood red. In the freezing Bering Sea, this blue blood is thicker and better adapted to extreme cold than the warm-water blood of their tropical cousins.
• A mature female king crab can produce between 100,000 and 500,000 eggs in a single breeding season, holding them glued to her body beneath her tail for months. Yet only a handful of those millions of larvae survive to adulthood—the journey from egg to adult crab takes 4 to 5 years, and predators, starvation, and ocean currents kill nearly everything along the way.
• The Bering Sea king crab fishery is so intense it has become the deadliest job in the world, with crews facing 300-knot waves and 40-knot winds to catch animals worth thousands of dollars each. In 2022 alone, the commercial harvest was worth over 1.2 billion dollars—the value of a single crab can exceed $500. This boom-and-bust cycle has crashed crab populations twice since the 1980s, reshaping an entire ecosystem.

At a glance

About the King Crab

In the dark, mysterious depths of the ocean, the king crab reigns supreme, its majestic legs sweeping slowly across the seafloor as it navigates the desolate landscape with deliberate, almost regal, precision. With its burnished shell glistening like polished bronze, this formidable crustacean moves through the water with a stately elegance, its very presence seeming to command the respect of its surroundings. As it glides effortlessly across the waves, the king crab embodies a quiet, unyielding power that is both captivating and humbling to behold.

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