BIOTIC

BIOTIC Species Information for Ensis ensis

Researched by

Jacqueline Hill

Data supplied by

MarLIN

Refereed by

This information is not refereed.

Reproduction/Life History

Reproductive type

Gonochoristic

Developmental mechanism

Planktotrophic

Reproductive Season

Summer

Reproductive Location

Insufficient information

Reproductive frequency

Annual episodic

Regeneration potential

Life span

11-20 years

Age at reproductive maturity

3-5 years

Generation time

Insufficient information

Fecundity

Insufficient information

Egg/propagule size

Insufficient information

Fertilization type

Insufficient information

Larvae/Juveniles
Larval/Juvenile dispersal potential	Insufficient information	Larval settlement period	Insufficient information
Duration of larval stage	1-2 months

Reproduction Preferences Additional Information

Life span
The life span of Ensis ensis is likely to be in excess of 10 years. The other two British species Ensis siliqua and Ensis arcuatus are also very long-lived, with a life-span up to 18 years (E. Fahy pers. comm.).

Reproduction
Razor shells in Britain do not appear to breed before they are three years old (Henderson & Richardson, 1994). Breeding occurs during the summer but larval settlement is not successful every year, and recruitment of juveniles is irregular (Hayward et al., 1996). Breeding probably occurs during spring and the veliger larvae has a pelagic life of about a month (Fish & Fish, 1996). Studies on razor shells from North Wales showed that individuals of Ensis ensis were mature in July but were spent in August, indicating that spawning had occurred by the middle of the summer (Henderson & Richardson, 1994).

Reproduction References