Multi-scale analysis among different types of river networks and their catchments have increased rapidly in tropical ecosystems. The concept of riverscapes brings together inter-disciplinary researchers to evaluate how major disturbances alter the energy sources and species composition in headwater food webs that are vulnerable to rapid climatic changes. Long-term studies of Caribbean streams in the Luquillo Mountains of Puerto Rico illustrate how cumulative effects and land-use legacies have affected the riparian forests and their connections with decapod-dominated food webs.
Results/Conclusions
The distributions of five species of Macrobrachium (M. acanthurus, M. carcinus, M.crenulatum, M. faustinum, M. heterochirus) are affected by abiotic factors (salinity, water temperature, and elevation) as well as by biotic factors (completion, cannibalism). Adaptations to disturbances from extreme high and low flows differ among species that reflect their life histories and patterns of movement, especially during prolonged dry periods. Contraction of pool habitats alters stream water quality and increases species densities and interactions. Pulses of riparian leaf litter fill shallow pools during these extreme dry periods. Pulses of riparian leaf litter and wood inputs occur during high winds associated with tropical storms and hurricanes. How the frequency and intensity of these disturbances will change in the future is now a major concern because sustaining these decapod populations is highly uncertain if headwater refuges from predatory fishes are eliminated or widely restricted in riverscapes throughout the Caribbean region.