Notas sobre interações competitivas envolvendo formigas poneromorfas

Abstract

*[We present a series of behavioral observations obtained from field observations concerning interspecific interactions of poneromorph ants, in an attempt to answer what the potential competitors are for this group of ants. We analyzed this using artificial groupings of species with similar ecologies, interacting in space & time, overlapping in their ecological niches & sharing resources with other species of syntopic ants. The records analyzed were made by the authors at different times, over more than 20 years. We applied field observation protocols at various sites in Brazil, including the Cerrado vegetation types, Deciduous Forest, Pantanal, Caatinga, Chaco, & Atlantic Rainforest. The discontinuous periods of field expeditions totaled approximately 200 hours of observation. The first phenomenon, that investigated, was the existence of interspecific aggressive behavior at baits, against a backdrop of direct competition for the established resource. We categorized the observed behavioral acts into action & reaction of interacting species. When we found dominance at the food supply, we investigated how it took place? We asked what behavioral categories, foraging strategies, & morphological traits would be involved in those interactions that resulted in dominance at baits & subsequent exclusion of other species? Another issue investigated is whether one species is always dominant, regardless of which species are present at the same bait. At approximately half of the baits observed, interspecific aggression was observed. Our results indicate that a more persistent resource is not a prerogative for certain behaviorally aggressive species, & they may also employ other important strategies in this context, for example, mass recruitment. Although poneromorphs are usually aggressive predators, they are seldom dominant at baits, possibly due to them having individual foraging strategies or tandem recruitment. However, they often visit the food source & collect food, even in the presence of other species. The fact that poneromorphs are generally large allows them to obtain a comparable amount of food to that of species with massive recruitment capabilities. Diversification in the diet of these ants induces niche overlap, which, in tropical environments with high spatial heterogeneity, allows the coexistence of different resource-sharing strategies. The epigaeic species of Ponerinae, Ectatomminae, & Paraponerinae, seem to clearly establish their foraging areas, recognizing those enemies that are in the same morpho-functional space, thus avoiding contact & dispute over food supply & recognizing their 'intimate enemies'.]