Feeding habits of juvenile Siganus fuscescens in a subtropical seagrass meadow estimated by rearing experiments and dual stable isotope analysis

Abstract

Rearing experiments were conducted using newly settled rabbitfish collected in subtropical seagrass meadows. Mean standard length on day 92 in the treatment fed on krill and seagrass (Thalassia hemprichii) was significantly larger than those of rabbitfish fed on only krill. The mixing models demonstrated that contribution rates of seagrass in the treatment fed on krill and seagrass was 0.7-15% (95% confidence interval). Contribution rates of seagrass for wild rabbitfish were equivalent to those of reared fish. These results suggest that the contribution of seagrass as an energy source is relatively small for juvenile rabbitfish in subtropical seagrass meadows.