Spider Crab

Unwelcome sight for those afflicted by Arachnophobia

Author: Pat
10th March 2012

The Spider crab looks like something out of ‘Alien’. Underwater, no-one can hear you scream…

typically has a shell encrusted with seaweed or barnacles

The arthropodic Spider Crab, or Hyas araneus is another seasonal visitor to recreational depths, usually between Spring and Summer. And when they’re in town, they’re really in town – it’s not unusual to see swarms of them falling over each other as they make their way to the shallows. Divers documented a recent mass migration into shallow waters around Cardigan Bay in Wales, for example.

If you’re finning across the bottom, watch out where you put your hands: although up to 110mm in size Spider Crabs typically have a shell encrusted with seaweed, barnacles and other hangers-on, which can make them difficult to spot, despite their considerable size. And they don’t take kindly to being poked.

Although not a mainstay of our diet over here, Spider Crabs taste rather good and not one to miss a commercial opportunity, UK fishermen catch around 5,000 tonnes annually.


  • Normally lurking around the 120m zone
  • Spider Crabs amble into shallow <20m depths from roughly April to June
  • English Channel northwards, North Sea and Baltic
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