Proportion of baits per plant occupied by ants

These data set includes the proportion of baits per coffee plants occupied by different ant species. It also includes the distance of the plant to the central Azteca nest. We use these data to analyze a system of diffuse competition in an ant community in a tropical coffee landscape in southern Mexico. The community is constrained by space in that the dominant competitor (Azteca seriaceasur) has a limited range of influence within which it excludes most other species, but outside that range, the other species may all persist. We use a simple dynamic model in which variable A, the dominant competitor, competes strongly with variable S, the collection of all other species in the system, the latter acting as a single strong competitor in the context of diffuse competition. Two qualitatively distinct outcomes are expected depending on the strength of competition: 1) a simple monotonic increase in species richness as the distance from the Azteca nest increases or 2) a range of distance from the nest in which there is bi-stability (either A dominates or S dominates), bookended by critical transitions. Studying five specific nests in wet and dry seasons over a two-year period, we find evidence for the bi-stability situation. Implications for metacommunity structure are discussed.