Nuclear species in Peruvian Amazonian mixed-species flocks are differentially attractive to transient species and to each other/Especies centros en la Amazonia de Peru son atraidos diferentemente a especies transitorios y del otro

In resident Amazonian mixed-species flocks, the pattern of attraction of transient species to nuclear Dusky-throated Antshrikes (Thamnomancs ardesiacus) and Long-winged Antwrens (Myrmotherula longipennis) and the pattern of heterospecific attraction between the nuclear species are undocumented. Patterns of attraction can help elucidate the nature of interspecific relationships (i.e., whether they are mutualistic, commensal, or parasitic). We played Dusky-throated Antshrike and Long-winged Antwren vocalizations to flocks and recorded how many transient species approached the playbacks, whether the antshrikes and antwrens were attracted to each other's playbacks, and how strongly they responded to the playbacks. More transient species were attracted to the antshrike vocalizations than antwren vocalizations, and more transient species were attracted to antwren than control vocalizations. Dusky-throated Antshrikes and Long-winged Antwrens approached each other's playback significantly more often than they approached control playbacks; the antwrens responded significantly more strongly to antshrike vocalizations than the antshrikes did to antwren vocalizations. Species may be more attracted to Dusky-throated Antshrikes because of their reliable alarm calling, whereas species may be attracted to antwrens because they serve as a flock indicator. Finally, Dusky-throated Antshrikes and Long-winged Antwrens likely confer benefits to each other, but those benefits may not be symmetrical. Received 7 August 2016. Accepted 3 March 2017. Key words: antbirds, interspecific interactions, mutualism, Neotropical, playback, Thamnophilidae. En bandadas mixtas que viven en Amazonia, la pauta de attracción de especies transitorios y especies centros, como los Thamnomanes ardesiacus y Myrmotherula longipennis, y la pauta de attracción entre los especies centros no son documentados. Pautas de attraccion puede elucidar el índole de las relaciones entre especies diferentes (como mutualismo, comensalismo, o parasitismo). Tocamos vocalizaciones de T. ardesiacus y M. longipennis a bandadas mixtas y recordamos el numero de especies que acercaron, si T. ardesiacus y M. longipennis se atrajeron a sus vocalizaciones, y la fuerza de atracción. Más especies transitorios se atrataron a las vocalizaciones del T. ardesiacus que el M longipennis, y más especies transitorios de atrataron a las vocalizaciones del M. longipennis que el control cientifico. T. ardesiacus y M. longipennis acercaron las vocalizaciones del otro más que ellos acercaron la vocalizacion del control; el M. longipennis respondió con mas fuerza a las vocalizaciones del T. ardesiacus que el T. ardesiacus respondió a las vocalizaciones del M. longipennis. Es possible que los especies son más atraidos al T. ardesiacus porque el T. ardesiacus hace vocalizaciones alarmas cuando hay un depredador. Al fin, el T. ardesiacus y el M. longipennis probablemente conficron beneficios al otro, pero los beneficios son asimétricos. Palabras clave: hormigueros, intcraccines interespecíficas, mutualismo, Neotropical, reproducción dc vocalizaciones, Thamnophilidae.
Hundreds of species worldwide participate in mixed-species flocks, defined as [greater than or equal to]2 species moving together for [greater than or equal to]5 min without a concentrated feeding source [...]