Can Caribbean coral populations be modelled at metapopulation scales?

Understanding and predicting the connectivity of coral reef organisms linked by larval dispersal is a key goal of tropical coastal ecosystem science and management. As oceanographers make advances modelling transport processes between reefs, ecologists should be prepared to embrace the population dynamics of organisms at larger metapopulation scales. A metapopulation is demographically closed but contains multiple open local populations. Metapopulation models of coral dynamics would aid the identification of larval source and sink areas and help identify the boundaries of demographically closed populations. Metapopulation models would also aid the understanding of species extinctions and help formulate transboundary management strategies to conserve ecosystem function. Existing metapopulation models are not spatially realistic or proven to represent physical and biological processes at appropriate spatial and temporal scales. Before more realistic alternatives can be established, further research is needed into (1) the larval transport between reefs (i.e. the coupling of reef-scale and oceanic models of water circulation, the pre-settlement mortality rates of larvae, and larval mobility in the water column), (2) the influence of larval supply on coral population dynamics at local (10s of kilometres) scales (i.e. processes of settlement behaviour, post-settlement mortality, and the pre-emption of space by algae), and (3) processes affecting the net fecundity of local populations (i.e. interactions of colony size, partial mortality rate, competition with algae, and the influence of habitat, physical disturbance, herbivore pressure, nutrification and sedimentation)