Published online by Cambridge University Press: 17 July 2014
Community structure, species composition, and changes over time afterdisturbances are frequently studied using common descriptors. We used rankabundance distribution plots (RADs), Rényi entropy plots, common theoreticalcommunity models, ordination analysis of similarities (ANOSIM and Clusters),and abundance spectra analyses to study the effects of a gradual naturalpopulation decline and an anthropogenic punctuated disturbance on thestructure of octocoral communities in Panama, considered a hot spot area foroctocoral diversity in the Tropical Eastern Pacific. Over a 17-month period,no significant change was found in community structure after a naturalyearly population decline of 25.2%. After a disturbance, however, differentrecovery trajectories were observed in various coral communities. Possiblephysical and biological explanations for the observed differences includeinitial local species diversity and abundance, species life historypatterns, colony morphology, and the geographical location of the community.Differences in community structure between study sites were best describedusing a combination of community descriptors, RADs, and abundance spectra.Rényi plots were useful in identifying changes in community structure,whereas the extent of the changes was best evaluated using ANOSIM andcluster analysis.