MEPS 537:205-215 (2015)  -  DOI: https://doi.org/10.3354/meps11457

ABSTRACT: An understanding of the responses of fish assemblages to disturbance events is central to the ongoing management of coral reef habitats. To understand the factors shaping patterns of recovery, we examined the recolonisation of populations of small cryptic fishes following experimental removal. After removing resident cryptobenthic reef fish assemblages from otherwise undisturbed coral rubble areas we observed a rapid recovery. Within 8 wk, fish assemblages were similar to their pre-removal structure in terms of fish abundance, species diversity and species richness. However, species differed in the speed and nature of their return. The return of larger species (e.g. Parapercis cylindrica) was largely mediated by recolonisation, while smaller, less mobile species (e.g. Eviota spp. and Enneapterygius spp.) relied primarily on recruitment, presumably from the plankton. Although patterns of settlement and recruitment are ultimately responsible for replenishment of local populations, our data suggest that mobility may play a strong role in restoring fish assemblages in the short term. These results have significant implications for our understanding of the response of coral reef ecosystems to disturbance events and highlight the importance of selecting appropriate criteria for evaluating reef resilience. If these short-lived fish species are a model for their longer-lived counterparts, it suggests that local responses to disturbance will depend largely on the mobility of species. Identifying both the recruitment and movement abilities of species will be critical in understanding the ability of fish assemblages to recover after disturbance.

KEY WORDS: Coral reefs · Cryptobenthic reef fish · Assemblage · Habitat disturbance · Postsettlement movement · Resilience · Size at settlement