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Crayfish
| Like the crab and the shrimp, the crayfish wears its skeleton outside
its body like a suit of armour. The proper name for these shell-covered
creatures is crustaceans, derived from the Latin word crusta, meaning
'crust' or 'shell'. As the crayfish grows, the outer shell periodically
splits and the soft-shellled animal emerges.The new shell gradually
hardens, completing the process known as moulting. With close-set eyes
giving it a shifty, criminal look, powerful jaws set in an underslung
mouth, and stiff red hair covering eight legs armed with claws, the
crayfish is certainly noted for the taste of its flesh far more than for
its good looks.Breeding takes place when the male deposits a gelatinous
mass of sperm-bearing fluid on the females breast which is still soft
after moulting. After fertilisation , the eggs are extruded and attached
to sticky hairs beneath the female's tale, looking like tiny bunches of
berries or grapes. From this similarity stems the term 'in berry', which
describes the female's condition when she is carrying up to 180 000
fertilised eggs.The eggs hatch in October and November. The microscopic ,
transparent , leaf-like larvae rise to the surface and are carried into
the open sea by currents. Moulting several times, the larvae take up to 11
months to complete metamorphosis from larcae to tiny crayfish. Only now do
they head back to the rocky shallows off the coast. Living as predators on
many kinds of sea-life, but particularly on mussels and urchins, they grow
slowly untill after four to five years they are sexually mature. At
between seven and ten years the male reaches the size at which he may be
caught for human consuption. It takes the female about twenty years to
reach this stage.
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