Crab Facts



  • Crabs and lobsters are part of an enormous group of creatures called crustaceans.
  • Most crabs and lobsters have their own shell, but hermit crabs live inside the discarded shells of other creatures.
  • Crabs and lobsters are decapods, which means they have ten legs — although the first pair are often strong pincers which are used to hold and tear food.
  • For spotting prey, crabs and lobsters have two pairs of antennae on their heads and a pair of eyes on stalks.
  • One of a lobster’s claws usually has blunt knobs for crushing victims. The other has sharp teeth for cutting.
  • Male fiddler crabs have one giant pincer which they waggle to attract a mate.
  • Robber crabs have claws on their legs which they use to climb up trees to escape from predators.
  • Lobsters are dark green or blue when alive and only turn red when cooked.
  • Apart from climbing trees the robber crab is notable for another strange and unfortunate characteristic — it drowns in water!
  • The giant Japanese spider crab can grow to measure 3 m across between the tips of its outstretched pincers.
  • When American spiny lobsters migrate, they cling to each others’ tails in a long line, marching for hundreds of kilometers along the seabed.
  • Sponge crabs hide under sponges which they cut to fit. The sponge then grows at the same rate as the crab and keeps it covered.