Putting it to Work: New publication evaluates impacts of predation on reefs in two oceans

Tropical regions are, in general, more diverse than ecosystems at higher temperate latitudes. A commonly held hypothesis is that the diverse predators in tropical regions cause predation to have a relatively stronger role in shaping communities. Data from the REEF Volunteer Fish Survey Project (VFSP) were used by Michele Repetto and colleagues from the Smithsonian Tropical Research Institute to test for underlying differences in regional fish diversity that could contribute to variation in predation intensity and impact. Their study spanned across the Isthmus of Panama, including two tropical ocean basins. The research team combined field experiments and VFSP data collected by REEF volunteers from both the Tropical Western Atlantic (TWA) and Tropical Eastern Pacific (TEP) survey regions. Their findings demonstrated that while the influence of predation is highly variable even within tropical systems, increases in predator diversity due to localized abiotic factors (such as seasonal upwelling) led to an increased influence of predators on their prey base. The study was recently published in the scientific journal Proceedings of the Royal Society B.

The authors observed striking spatial and seasonal variability in predation impact and intensity on coastal marine invertebrate communities. This variability likely has important consequences for food web dynamics and patterns of species diversity and ecosystem functioning. The Isthmus of Panama offered a unique opportunity to explicitly test factors that influence temporal and spatial variability of predator effects in tropical marine communities. The analysis included data on 115 fish species from 16 families in the TWA and 89 species from 18 families in the TEP. Because the REEF VFSP program occurs worldwide, this citizen science dataset provides a valuable source of information to scientists and researchers from government and academic institutions that is otherwise not available. To see all studies and scientific papers that have included REEF data, visit www.REEF.org/db/publications.