Do Flycatchers (Tyrannidae) share foraging space in a fragment of Atlantic Forest, Brazil?

Abstract

Representatives of the Family Tyrannidae are generally insectivores. The strategies used by birds during foraging are consequences of interactions of morphology, feeding preference, behavior, habitat selection, prey availability, and the relationships between predators and competitors. Thus, here we propose that the species in this family avoid temporal and spatial overlap during foraging. To test this hypothesis, we observed the foraging of several local species and compared the different foraging methods used. Five different environments were sampled in relatively open, savanna-like anthropogenic areas. Sampling was carried out over two days, between 06:00-12:00 h and 14:00 to 17:30 h for a total of 21:40 h sampling effort and during the period of greatest activity of the birds. A total of 135 observations of four species, including 53 observations of Tyrannus melancholicus, 43 of Pitangus sulphuratus, 24 of Machetornis rixosa and 15 of Myiozetetes similis. Tyrannus melancholicus had 40% of their foraging records in short range, 80% of records using the canopy and was found in all habitats sampled; Pitangus sulphuratus presented 56% of its records in long straight flights and 75% of records using the middle stratum and was found in all sampled habitats; Machetornis rixosa tended to forage on the ground (75%) and was found in only two of the habitats sampled. Myiozetetes similis tended to forage in long straight flights (60%), mostly in the canopy (90%) and was only found in one habitat type. Based on the analyzis and results from the present study we observed that species of the Tyrannidae have similar eating habits, yet still coexist in the same environment, sharing resources by using different foraging strategies, thereby avoiding potential competition.