Behaviour 2019
Inter- and Intraspecific Dominance Hierarchies in a Cloud Forest Hummingbird Guild.
Facundo Fernandez-Duque1, Sophie Rabinowicz2, Eliot Miller3, Jay Falk2, Matias Fernandez-Duque4, Dusti Becker5,6, Mark Hauber7. 1Yale University, New Haven, Connecticut, United States; 2Cornell University, Ithaca, NY, United States; 3Cornell Lab of Ornithology, Ithaca, NY, United States; 4Northwestern University, Chicago, Illinois, United States; 5Reserva Las Tangaras, Mindo, Pichinca, Ecuador; 6Life Net Nature, Online, , United States; 7University of Illinois at Urbana-Champaign, Champaign, Illinois, United States

Competition for resources frequently drives intra- and interspecific interactions. Regardless of the outcome, direct competition and contact for a resource can be detrimental to the individuals involved, making it adaptive to settle harmful disputes by signaling the individual’s resource holding potential (RHP). Body size, ornamentation, and phylogenetic distance between species have been tied to dominance in local avian communities. We constructed a dominance hierarchy based on scoring individuals from 12 hummingbird species as aggressors or receivers during 2,611 interactions observed within 0.5 m of different nectar feeders through 57 1-hr focal periods in the 2019 wet season in Mindo, Ecuador. We evaluated the associations among body size, plumage coloration, exploratory behavior, and phylogenetic distance between species and their calculated dominance rank. Interspecific dominance rank was positively correlated to species’ body size, whereas small-bodied species discovered novel food sources first.