BIOTIC

BIOTIC Species Information for Ostrea edulis
All Taxonomy Biology Distribution Reproduction

Researched by	Angus Jackson	Data supplied by	MarLIN
Refereed by	This information is not refereed.
General Biology
Growth form	Bivalved	Feeding method	Active suspension feeder
Mobility/Movement	Permanent attachment	Environmental position	Epifaunal
Typical food types	Suspended organic particles.	Habit	Attached
Bioturbator	Not relevant	Flexibility	None (< 10 degrees)
Fragility	Robust	Size	Small-medium(3-10cm)
Height	Insufficient information	Growth Rate	Insufficient information
Adult dispersal potential	None	Dependency	Independent
Sociability	Gregarious
Toxic/Poisonous?	No
General Biology Additional Information	There is some evidence that reduced growth, weight and poor conditions are a consequence of high population densities (300 per square yard). Size and shape can be extremely variable. Because the oyster cements itself to the substratum, growth of neighbouring individuals may result in competition or space and distort the usual shell shape. Feeding is carried out by pumping water through a filter in the gill chamber removing suspended organic particles. The native oyster starts life as male, becoming mature at around 3 years of age. After spawning the oyster becomes a functional female. Larvae are seldom produced by oysters under 50 mm. Growth is quite rapid for the first year and a half. It then remains constant at around 20 grams per year before slowing down after five years. In the British Isles, the main growing season is from April to October. The oyster faces serious competition from the introduced species Crepidula fornicata, the slipper limpet. Brought over from the United States this species can occur in very high densities competing for space and food. The slipper limpet deposits pseudo faeces which forms 'mussel mud' changing the substratum and hindering settlement. Native oysters are preyed on by a variety of species including starfish and Ocenebra erinacea, the sting winkle or rough tingle. Buccinum undatum, the common whelk also feeds on oysters but not as exclusively as the sting winkle. Urosalpinx cinerea, the American oyster drill was accidentally introduced to the British Isles with American oysters. This species lives on oyster beds and feeds almost entirely on oyster spat.
Biology References	Lilley, 2000, Dare, 1982, Sheldon, 1968, Richardson et al., 1993, Askew, 1972, Hutchinson & Hawkins, 1992, Yonge, 1960, Korringa, 1952,