Ecologia trófica de Conopophaga lineata (Wied, 1831) e Conopophaga melanos (Vieillot, 1818) (Aves: Conopophagidae): aspectos das relações de nicho e seleção de presa

Abstract

Data on the food ecology of two understory birds were collected at the Municipal Reserva Biológica Municipal do Poço D’anta, Juiz de Fora – MG, Southeastern Brazil. Conopophaga lineata and Conopophaga melanops are found occurring in sympatry in some localities of the Southeast Region. Studies with related and sympatric species may be useful in assessing the influence of the niche on co-occurrence and co-existence. During the samplings using ontological networks were carried out 29 catches of 25 individuals of C. lineata, and 28 catches of 21 individuals of C. melanops. In the sorting of the fecal samples of C. lineata and C. melanops were found, respectively, 310 and 276 items. C. lineata consumed predominantly Formicidae (53.5%), Coleoptera (6.8%). However, Coleoptera dietary index (AI) (7.47) was below other groups such as Formicidae (68.2) and Araneae (8.80). C. melanops consumed high proportions of Formicidae (23.2%), Coloptera (12.3%), Orthoptera (11.6%) and Isoptera (11.2%), although in terms of AI the predominance was Formicidae (24.66) and Coleoptera (20.14). The niche overlap between species was higher than expected (observed = 0.723). Although differences in the proportions of the types of arthropods consumed were not sufficient to reveal separation of their food niches. Although it is found in the literature that C. lineata selects both prey and arthropod species larger than 5 mm in proportions above that expected by chance, just as it was observed for C. melanops preferential predation on some taxa. The results show that, in some cases, the ecological patterns of bird responses to the resources found in the environment may be different from those found in other regions.