Dug down during the winter

During the winter the shore crab is rather sluggish and passive. During this period they are often found dug down into the bottom sediment in shallow water. Here, the water is a little warmer and there is little risk of hem being caught in the ice. Ice can stop the flow of oxygen from the air to the water and give rise to oxygen deficency where the water is shallow and the currents are weak.

Over the world

Shore crabs have larvae that can drift over vast areas with sea currents. Adult crabs can start on long journeys. If adult crabs are marked, it is possible for them cover large distances even after a few months.
    Shore crabs are found along the whole of the eastern Atlantic seaboard, from Norway to West Afrika. They are even found in the Mediterranean and have been introduced to many other places in the world, for example NE America.

Males and females

Shore crabs became sexually mature at about 1 year. At this time they are about 2-3 cm over the carapace. Shore crabs can be as old as 4 years. The males are normally larger than females of the same age.
    It is easy to distinguish the gender of adult shore crabs. By closely studying their tails that are tucked in under their bodies it is possible deduce their sex. Tails on the males have 5 segments and are slim and pointed, whereas on the females the tail has 7 segments, is wider and rounded.
    The female uses her wider tail to protect the fertilized eggs. Beside her tail she has four brush furnished legs where she can stick her eggs.
    Most shore crabs mate during the late summer or early autumn.

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Eaten by many

Eats most things

Active at night

Pick it up with your hand

Even on land

Dug down during the winter

Over the world

Males and females

Eggs and young

Shore crab    More info     Photo     Other names
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Bo Johannesson | Martin Larsvik | Lars-Ove Loo | Helena Samuelsson