BIOTIC Species Information for Amphiura chiajei
|Researched by||Lizzie Tyler||Data supplied by||University of Sheffield|
|Refereed by||This information is not refereed.|
|Feeding method||Surface deposit feeder
Sub-surface deposit feeder
|Typical food types||Organic detritus.||Habit||Free living|
|Bioturbator||Flexibility||High (>45 degrees)|
|Height||Insufficient information||Growth Rate||0.5 mm/year|
|Adult dispersal potential||1km-10km||Dependency||Independent|
|General Biology Additional Information||Feeding method
Amphiura chiajei buries in the sediment with its disc at 4-6 cm depth. One or two arms are stretched up above the sediment to collect food at the surface. Food particles are then transported along the arms to its mouth and ingested (Buchanan, 1964).
The species is mostly found in low numbers throughout its range, although a number of high density populations are reported. Survey work by Keegan & Mercer (1986) revealed Amphiura chiajei to be a dominant member of the bottom community in Killary Harbour (a fjord-like inlet on the west coast of Ireland). The highly dense population of about 700 individuals per m², occurred in sediments with a silt/clay content of 80-90% and organic carbon levels of 5-7%. In contrast, Buchanan (1964) reported the mean population density of Amphiura chiajei to be 13 individuals per m² off the Northumbrian coast.
Interactions with other species
The heart urchin, Brissopsis lyrifera, which typically co-occurs with Amphiura chiajei, can negatively affect the growth of body and gonads of Amphiura chiajei, whilst Amphiura chiajei seemingly has no effect on the growth of Brissopsis lyrifera. Hollertz et al. (1998) suggested that this was attributable to the extensive bioturbation of the sediment caused by Brissopsis lyrifera.
|Biology References||Buchanan, 1964, Keegan & Mercer,1986, Hollertz et al., 1998, Aizenberg et al., 2001, Hayward & Ryland, 1990,|