Larval settlement behaviour of the barnacle Balanus reticulatus in the laboratory

Abstract

The effect of algal food concentration, substratum, light, salinity, cyprid density and 'footprints', cyprid age, films of organic biopolymers, bacteria and diatoms on the settlement of Balanus reticulatus cyprids were studied. The algal food quantity (from 7 × 104 to 4 × 105 cells ml-1) fed to nauplii had a significant effect on the settlement. Cyprids failed to settle on glass surfaces but would settle on polystyrene. Light, cyprid 'footprints' and age significantly affected the settlement, however, salinity (from 20 to 40 psu) and cyprid density (from 5 to 200 per 5 ml of seawater) had no effect on the settlement. Films of organic polymers, bacteria, and diatoms inhibited the settlement compared to control. It is suggested that cyprids of B. reticulatus can serve as an appropriate test material for antifouling bioassays in those areas where the former forms a dominant species.