Behavior and Social Organization during the Breeding Season in Mionectes oleagineus, a Lekking Flycatcher

Abstract

The social systems and behavior of Tyrannids are best known for the North American representatives, a small percentage of a large and diverse family. In this paper, we describe the breeding season social organization and behavior of the Ochre-bellied Flycatcher, Mionectes oleagineus, a lek-breeding Neotropical Tyrannid. We describe three distinct categories of males. Territory owners defended display territories either solitarily or at small leks of two to six males. Territories at leks shared common defended boundaries and, overall, territories averaged 763 m2 in size. About 10% of banded males behaved as subordinate satellites on the territories of other males. These individuals eventually replaced the owner on the territory. Forty-eight percent of banded males did not hold or associate with a display territory. Instead, these individuals behaved as floaters and moved widely over the study site. The majority of visitors at display territories were males, despite an apparently even sex ratio in the population. Interactions between individuals, including display and copulation, are described.