Ochre Sea Star Behaviour

Feeding, Hunting & Foraging Behaviour of the Ochre Sea Star

The ochre star is the most air tolerant of all the Pisaster species. It feeds year-round in the low and middle intertidal zones, and sometimes into the subtidal. The ochre sea star prefers wave-washed rocky shores from Prince William Sound, Alaska to southern California. It preys on mostly mussels, but the sea star also eats barnacles, snails, limpets, and chitons. The sea star uses hydrostatic pressure of its tube feet to gradually open shells of mussels.  It then everts the stomach to digest food outside the body cavity. The purple sea star occurs along the seashore

Courtship & Breeding Behaviour of the Ochre Sea Star

Sea stars develop male gametes early in life and later produce females gametes. There is a transition period when both gametes are produced by the same individual. Maturing gonads increase in size and expand into the arms. Small openings known as gonopores open to release eggs or sperm into the water from the base of the arms. Sexual reproduction occurs from May to July in southern British Columbia and probably earlier in the south and later in the north. Gonads release eggs and sperm into the surrounding water where fertilization occurs resulting in free-swimming larvae. The larvae join the plankton where it preys on small planktonic plants and animals. Not much is known about settlement and growth. Purple and orange forms are the most frequent colour but some ochre stars are yellow or brown in colour.

Ochre Sea Star Locomotion and Movement

The ochre sea star travels by using hydrostatic pressure to move its tube feet. It will move up a beach with the tide to find its prey and retreat into deep water or rock crevices when the tide falls. Sea stars can withstand up to 8 hours out of water during low tides, but they has a low tolerance to warm water and low oxygen levels.