Abstract
Habitat selection plays a fundamental role in determining community structure and species coexistence, although the role played by sexual selection in shaping settlement patterns is less well understood. Manakins (Pipridae) are a Neotropical family of lekking birds that exhibit similar behavioral ecology across species, both in terms of resource use and dependence on elaborate visual signaling for mate attraction, yet they differ in the form of their sexually selected displays and ornaments. We characterized and compared the spatial dispersion and habitat attributes of lek sites for four species of sympatric manakins in the Chocó region of northwestern Ecuador to test several hypotheses for habitat selection and lek dispersion. First, the interspecific hotspot hypothesis predicts that if males establish leks in locations where females are likely to be encountered (e.g., resource-rich patches, topographic channels), then leks of ecologically similar species should cluster in geographic space due to shared patterns of resource use among species. Alternatively, the habitat partitioning hypothesis predicts leks of ecologically similar species to exhibit uniform spatial distributions to minimize competition for shared resources. Finally, the signal enhancement hypothesis proposes that males should establish leks in habitats with ambient light or structural properties optimal for the transmission or production of species-specific mating signals, and thus leks of different species should segregate in environmental space. We found that leks of sympatric manakin species were randomly distributed in geographic space, inconsistent with the interspecific hotspot and habitat partitioning hypotheses. In addition, manakin species segregated in environmental space based on forest structure characteristics related to visual signaling. These findings suggest that landscape-level lek site dispersion by sympatric manakins may be primarily influenced by sexual display optimization rather than mechanisms related to their shared ecology. Moreover, this study flags the local population of Masius chrysopterus as a potential conservation concern due to its distinct and limited elevational preferences.