Breeding density affects the honesty of bird vocal displays as possible indicators of male/territory quality

@article{citeulike:3210861, abstract = {Vocal displays are supposed to be an honest signal of the phenotypic and genetic quality of individuals and their territory. Moreover, signal interactions are nearly always associated with individuals in aggregations, and their function could in part be explained as social behaviour. Conspecific density has been shown to be a particularly strong proximate and ultimate factor acting on several individual/population features; thus, it may be expected to affect vocal behaviour too. Here, I investigate the hypothesis that, in long-lived, territorial species, density affects the vocal displays of mated males, masking their honesty as a possible signal of male/territory quality. Each month I listened to the dusk calls of 17 breeding male Eurasian Eagle Owls Bubo bubo during their prelaying period. Nine males bred in a low-density situation, the other eight in a high-density one. Conspecific density was found to affect the honesty of call features as signals of male and/or territory quality. The call display as a reliable predictor of male fitness measured as productivity persisted only in situations of high breeding owl density, where male2013male competition was stronger. Accommodation of call activity allows individuals to minimize the costs of aggressive calling by adjusting the territoriality threshold to local conditions. The results of this study emphasize the importance, when investigating the evolution and maintenance of honest territorial or sexual signals, of considering the environmental and social context experienced by the individual, thereby corroborating the idea that male2013male competition contributes to the maintenance of honest signalling.}, address = {Department of Applied Biology, Estaci\'{o}n Biol\'{o}gica de Do\~{n}ana (EBD), Consejo Superior de Investigaciones Cient\'{i}ficas, Avda. de Mar\'{i}a Luisa s/n. Pabell\'{o}n del Per\'{u}, Apdo. 1056, 41013 Seville, Spain}, author = {Penteriani, Vincenzo }, citeulike-article-id = {3210861}, comment = {In a study of a french population of eagle owls, found that population density predicted 'honesty' of male call duration. In denser populations, positive correlation between reprod success and song duration. Negative correlation in less dense populations. Interesting finding--could apply to barn swallows on a much finer scale.}, doi = {http://dx.doi.org/10.1046/j.1474-919X.2003.00173.x}, journal = {Ibis}, keywords = {bird, breeding, density, displays, honest, signal, vocal}, number = {3}, pages = {E127--E135}, posted-at = {2008-09-09 21:39:48}, priority = {0}, title = {Breeding density affects the honesty of bird vocal displays as possible indicators of male/territory quality}, url = {http://dx.doi.org/10.1046/j.1474-919X.2003.00173.x}, volume = {145}, year = {2003} }

TY - JOUR ID - citeulike:3210861 L3 - citeulike-article-id:3210861 N2 - Vocal displays are supposed to be an honest signal of the phenotypic and genetic quality of individuals and their territory. Moreover, signal interactions are nearly always associated with individuals in aggregations, and their function could in part be explained as social behaviour. Conspecific density has been shown to be a particularly strong proximate and ultimate factor acting on several individual/population features; thus, it may be expected to affect vocal behaviour too. Here, I investigate the hypothesis that, in long-lived, territorial species, density affects the vocal displays of mated males, masking their honesty as a possible signal of male/territory quality. Each month I listened to the dusk calls of 17 breeding male Eurasian Eagle Owls Bubo bubo during their prelaying period. Nine males bred in a low-density situation, the other eight in a high-density one. Conspecific density was found to affect the honesty of call features as signals of male and/or territory quality. The call display as a reliable predictor of male fitness measured as productivity persisted only in situations of high breeding owl density, where male2013male competition was stronger. Accommodation of call activity allows individuals to minimize the costs of aggressive calling by adjusting the territoriality threshold to local conditions. The results of this study emphasize the importance, when investigating the evolution and maintenance of honest territorial or sexual signals, of considering the environmental and social context experienced by the individual, thereby corroborating the idea that male2013male competition contributes to the maintenance of honest signalling. IS - 3 JF - Ibis AD - Department of Applied Biology, Estación Biológica de Doñana (EBD), Consejo Superior de Investigaciones Científicas, Avda. de María Luisa s/n. Pabellón del Perú, Apdo. 1056, 41013 Seville, Spain EP - E135 TI - Breeding density affects the honesty of bird vocal displays as possible indicators of male/territory quality VL - 145 SP - E127 KW - bird KW - breeding KW - density KW - displays KW - honest KW - signal KW - vocal N1 - In a study of a french population of eagle owls, found that population density predicted 'honesty' of male call duration. In denser populations, positive correlation between reprod success and song duration. Negative correlation in less dense populations. Interesting finding--could apply to barn swallows on a much finer scale. AU - Penteriani, Vincenzo PY - 2003/// UR - http://dx.doi.org/10.1046/j.1474-919X.2003.00173.x ER -