(Kleppesjø
- Hordaland / 9 meters / 1.27.2001)
A total of 43 species
are registered along the coast of Norway.
They all have the mouth located under the central
disk. All arms are connected to this disk. Most sea stars have five
arms, but there are several exceptions. If an arm is lost, a new grows
out. As long as the central disk is intact, there is a god chance the
sea star will survive. This depends on food access while waiting for the new arms
to grow. The sea stars
feed on mussels, snails, many bristled worms and even other echinoderms.
On the tip of each arm there are
light sensitive organs acting as eyes. Every arm includes a hydraulic
system where water is used to extract the arm and muscles are used to
contract it.