Biology

Main spawning period is short, viz. from June to July. The larvae remain in the plankton for at least four weeks. This species seems able to adapt its reproductive strategy to different environmental conditions. In more temperate waters O. fusiformis produces a distinctive type of planktotrophic larva and breeding occurs in autumn.  

 O. fusiformis lives in tubes that are partly buried in the sediment and partly extended from the sediment. It is able to live in low oxygen concentrations for a short time. 

 O. fusiformis selectively ingests suspended and deposited particles. It feeds by means of the lobed tentacular crown, either in an upright position or bent over to the sediment surface, thereby exposing its anterior part. The species is often found in stomachs of flatfish, haddock and cod (Hartmann-Schröder, 1971; Wolff, 1973; Curtis, 1977; Fauchald & Jumars, 1979; Fish & Fish, 1989; Gentil et al., 1990).