BIOTIC

BIOTIC Species Information for Venerupis senegalensis
All Taxonomy Biology Distribution Reproduction

Researched by	Will Rayment	Data supplied by	MarLIN
Refereed by	This information is not refereed.
General Biology
Growth form	Bivalved	Feeding method	Active suspension feeder
Mobility/Movement	Burrower	Environmental position	Infaunal
Typical food types	Suspended organic matter, particularly unicellular algae	Habit	Burrow dwelling
Bioturbator		Flexibility	None (< 10 degrees)
Fragility	Intermediate	Size	Small-medium(3-10cm)
Height	Insufficient information	Growth Rate	1.3 mm/month
Adult dispersal potential	100-1000m	Dependency	Independent
Sociability	Solitary
Toxic/Poisonous?	No
General Biology Additional Information	Abundance Johanessen (1973a) recorded Venerupis senegalensis (studied as Venerupis pullastra) from a sheltered beach in Norway at a mean density of 31 individuals per 0.25 m². Potential production was calculated to be 20 g ash free dry weight per m²/year, including a loss of 9 g due to mortality. Growth rate Growth rate of Venerupis senegalensis varies according to environmental conditions. Quayle (1952) investigated growth rates of Venerupis senegalensis (studied as Venerupis pullastra) from Millport, Scotland. In the first year following settlement, mean monthly growth rate was 1.3 mm per month over the growing period of 6 months. Growth rate was found to increase for the first 4 years of life (maximum growth rate was ca 9 mm per season) after which it began to decrease. Within each growing season, growth rate was found to increase up to the point of spawning, after which it levelled off and then decreased. Johannessen (1973b) investigated growth of Venerupis senegalensis (studied as Venerupis pullastra) from a sheltered beach in western Norway. The spherical shell of the free swimming larvae developed into an oblong shape after settlement, presumably to aid burrowing. At a shell length greater than 40 mm, the shell shape tended towards a flattened circular form, the biological significance of which is unclear. The shell growth rate was found to be approximately constant (ca 15 mm per season) up to a shell length of 40 mm, after which it decreased. Short and/or young individuals were found to grow faster than long and/or old ones. Diet Beiras et al. (1993) investigated the effect of increasing food rations on Venerupis senegalensis (studied as Venerupis pullastra). Increased rations of algal food were found to increase ingestion rate and growth. This relationship was found to hold true up to the maximum ration of 300 algal cells/µl. However, at high food concentrations the returns diminished due to decreased absorption efficiency. The optimum food concentration for growth (i.e. maximum increase in biomass per unit weight of food) was 100 cells/µl.
Biology References	Fish & Fish, 1996, Hayward & Ryland, 1995b, Hayward et al., 1996, Johannessen, 1973a, Johannessen, 1973b, Quayle, 1952, Beiras et al., 1993,