Recurrent disturbances, recovery trajectories, and resilience of coral assemblages on a South Central Pacific reef

Abstract

Coral reefs are increasingly threatened by various types of disturbances, and a critical challenge for ecologists is to determine their ability for resistance and resilience. Like most other reefs worldwide, coral assemblages at Moorea, French Polynesia, have been impacted by multiple disturbances over the last four decades. These disturbances have caused large declines in coral cover, and subsequent colonization by turf algae, but this phase-shift from coral to algal dominance has not persisted. Instead, the composition of the coral community changed following the disturbances, and in this form, the reef returned to pre-disturbance coral cover within a decade. Thus, this coral assemblage is characterized by high resilience in terms of coral cover, but fragility in terms of species composition. Our results support the possibility that instead of a rapid collapse in response to disturbances, some coral reefs may undergo gradual changes in their community structure.