Description

Flower piercers (Diglossia) have a modification in the bill tip like a hook, which is used for drilling a hole in the corolla of flowers and obtaining the nectar. These birds share morphological similarities among them, but they are in inter-specific competition in the Andean forest. However, it is little the knowledge about the feeding strategies that they use to mitigate the interspecific competition. Thegoal of this study was to describe the strategies that three species of flower piercers (Diglossa humeralis,D. lafresnayii y D. cyanea) use to avoid competition for feeding resources in an Andean forest from Nariño. We made field direct observations of some individuals of Diglossa to describe the feeding strategies. Moreover, fecal samples of the three species were collected to study their preys. We found that the three species of flower piercers had similar forms of obtaining nectar, but they select some species of plants and type of p r e y. D. humeralis is much more generalist than D. lafresnayii and D. cyanea, which have lower amplitude in their feeding resources. This suggests that differences in the richness of food resources of the three species, their temporal geographic exclusion and morphological adaptations of the bill allow them occupying the same geographic area and being sympatric.