Benthic community recovery from small-scale damage on marginal Caribbean reefs: an example from Panama

Abstract

The frequency of small-scale physical damage to coral reefs is likely to increase as fishing and tourism pressures intensify. Predicting how reefs will respond to the effects of these types of damage requires empirical exploration, especially on reefs that are already heavily degraded. We replicated small-scale damage on four reefs that live close to their ecophysiological tolerance limits in the Bocas del Toro Archipelago of Caribbean Panama and quantified their recovery over 2 yrs. On each reef we cleared five replicate 1 × 1-m plots of all living benthos simulating physical damage by boat grounding, anchoring, or fishing practices. Recovery of the benthic community was quantitatively monitored and compared to adjacent non-cleared plots (treated as a control) every 6 mo. After 2 yrs, only one of the reefs exhibited evidence of recovery of the cleared plots. Poor recruitment of benthos appeared to slow down recovery of cleared plots on another reef. The other two reefs showed unequivocal shifts toward a macroalgae-dominated system, suggesting that small-scale disturbances could have lasting impacts on marginal reefs. We found no clear contemporary or historical environmental signal that could explain the differential dynamics of recovery amongst these reefs.