BIOTIC

BIOTIC Species Information for Balanus spp.
All Taxonomy Biology Distribution Reproduction

Researched by	Dan Bayley
Refereed by	This information is not refereed.
General Biology
Growth form		Feeding method	Active suspension feeder Detritivore
Mobility/Movement	Permanent attachment	Environmental position	Epilithic
Typical food types	Zooplankton, detritus	Habit	Attached
Bioturbator		Flexibility	None (< 10 degrees)
Fragility	Robust	Size	Small(1-2cm)
Height		Growth Rate
Adult dispersal potential	None	Dependency	Independent
Sociability	Gregarious
Toxic/Poisonous?	No
General Biology Additional Information	Feeding Barnacles feed by extending thoracic appendages called cirri out from the shell to filter zooplankton from the water. In the absence of any current, the barnacle rhythmically beats the cirri. When a current is present the barnacle holds the cirri fully extended in the current flow. Barnacles feed most during spring and autumn when plankton levels are highest. Little if any feeding takes place during winter, when barnacles rely on stored food reserves. Feeding rate is important in determining the rate of growth. Moulting Barnacles need to moult in order to grow. Frequency of moulting is determined by feeding rate and temperature. Moulting does not take place during winter when phytoplankton levels and temperatures are low.
Biology References	Rainbow, 1984, Barnes et al., 1963, Bassindale, 1964,