Abstract:
This thesis investigated feeding behavior, cirral anatomy, Reynolds numbers (Re's), and leakiness of the cirral fan for three barnacle species: Balanus glandula, Semibalanus cariosus, and Balanus nubilus. A study of the feeding of B. glandula revealed that newly-metamorphosed juveniles fed at Re's less than one and their cirral fan leakiness was <5% at current speeds of 4 cm/s. At this speed, large and medium individuals fed at Re's near unity, and their cirral fans were 6.8±O.7% leaky. The experiments were repeated using S. cariosus and B. nubilus with the same tissue mass as B. glandula. No clear species-specific or size-specific trends were identified in these species. The observed switch from low to high Re feeding in B. glandula may indicate a lower limit to the size of this species, if further research confirms low Re feeding is less efficient and field current velocities are sufficiently low.