Behaviour and ecology

Trophic strategy

Neocrinus decorus:

  • is a bottom-dwelling (epibenthic) filter feeder
  • feeds mainly on plankton
  • avoids coprophagae (eating its own faeces)

Behaviour

Neocrinus decorus is semi-sessile. It lives on the sea floor, mainly on hard substrates such as rocky outcrops, but doesn’t attach itself.

Like other crinoids, Neocrinus catches plankton by arranging its crown of arms into a parabolic fan and positioning this within a current. To process plankton more effectively, it faces the fan into the current. 

The arms bear numerous rows of pinnules from which mucus covered tube feet extend and catch plankton. Food particles are passed down the arms and into the mouth.

The animal’s stem holds the arms off the sea floor, helping to position them where the currents are usually strongest. The stem also enables Neocrinus to reach plankton its rivals cannot.

Migration

This crinoid is not known to migrate however individuals are capable of crawling to better feeding areas by using their arms for 'rapid' movement or cirri for slow movement.

Watch a YouTube video of Neocrinus decorus using its arms to move along the sea floor
  • Blue-headed wrasse
    Associations

    Find out about the predators and diseases that have an impact on Neocrinus decorus and what defences it might have.