Behaviour 2019
Spread the word: male manakins advertise the presence of display sites with neighboring competitors
Elsie H. Shogren1, W. Alice Boyle2. 1University of Rochester, Rochester, NY, United States; 2Kansas State University, Manhattan, KS, United States

Reproductive behavior is under natural and sexual selection, and variation in mate attraction investment reveals fitness trade-offs. Male White-ruffed manakins (Corapipo altera; Pipridae) exhibit variation in display investment, despite having a sexually selected mating system. We manipulated the social environment of male manakins to test three hypotheses explaining this variation: (1) individual quality and condition, (2) competition, or (3) cooperation. First, we broadcast sounds to simulate elevated display of neighboring males. Second, we temporarily prevented neighboring males from using their display sites, increasing competition at focal display sites. Males reduced vocalization in response to elevated acoustic signaling, suggesting males cooperate to minimize individual advertising effort. The number of individuals and silent displays increased when neighbors were prevented from displaying, consistent with the competition hypothesis. However, constancy in time investment suggests male quality or condition underlies some individual variation in behavior. This work demonstrates the importance of both intrinsic and social drivers shaping investment in courtship behavior.