Juvenile C. barbata (2-3 months old, 5cm high) were collected from loose boulders. The boulders were broken into small fragments holding 1–2 individuals that were transplanted onto the substrate using epoxy putty to form experimental plots comprising five transplanted individuals. Such plots were transplanted in four habitat types (i) ‘Native habitat’, (ii) Natural bedrock habitat, (iii) Artificial habitat – seaward side, and (iv) Artificial habitat – landward side. For each habitat, two replicated areas were established. Within each area, four plots with transplants were created in each of the following positions: (i) horizontally surrounded with naturally occurring adults (HA), (ii) horizontally without surrounding adults (HW) and (iii) vertically with no surrounding adults (V).
Disturbances (boulder overturning and different herbivory levels) may have impacted results.
Survival was 0% in native habitat (due to boulder overturning), >30% in landward artificial habitats, 20% in the natural bedrock habitats and 9% in the seaward artificial habitats. Differences were not significant except for the native habitat. No significant differences in the size of transplanted juveniles were found between native and other habitats. At the natural bedrock sites, caging did not influence the survival or the cover of juveniles. At the artificial sites in Marotta, uncaged transplants showed severe decline, with nearly 80% of the coverage lost within 8 days. By the end of the reproductive season (June 2009), all settlement plates had some C. barbata juveniles.
Nature of Disturbance:
Virtually no transplants survived in the native habitat after October 2008 due to boulder overturning and disturbance.