More about ship worms
Bores with its shell
Ship worm in its tunnel.
The ships worm is a mussel with a worm-like
body, where only a minimal part of the body is covered by a shell. The
wood protects the worm from predatory attack. The shell is used to bore
circular tunnels. To bore effectively, the worm has to lie firmly in its
tunnel. This is accomplished by pressing its body firmly against the tunnel
walls while the notched shell is effectively rasped against the wood.
To simplify its work, it is an advantage if the wood is thoroughly wet
and already damaged by micro-organisms.
Ships worms rarely bore into each others tunnels, or out
through the surface of the wood. Because of this, ship worms can, without
being noticed, cause great damage on wooden structures like boats and
piles if preventive measures are not taken, e.g. poisonous paints.