Variability of a consistent trait: The size of the white wing patch in European Stonechats Saxicola rubicola rubicola

Numerous bird species exhibit striking white patches on their plumages that have been reported as signals of individual quality in the context of sexual selection. While differences in white plumage traits between individuals have been well studied, phenotypic variation and factors affecting their c...

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Detalles Bibliográficos
Autores: Oficialdegui, Francisco J., Serrano, David
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2023
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/330762
Acceso en línea:http://hdl.handle.net/10261/330762
Access Level:acceso abierto
Palabra clave:Passerine bird
Phenotypic flexibility
Repeatability
Sexual selection
Trait expression
Wing patch size
Descripción
Sumario:Numerous bird species exhibit striking white patches on their plumages that have been reported as signals of individual quality in the context of sexual selection. While differences in white plumage traits between individuals have been well studied, phenotypic variation and factors affecting their consistency within the individual have received less attention. Here, we studied the consistency in the size of the white wing patch and its components of variation in a Spanish population of European Stonechats Saxicola rubicola rubicola monitored over six years (2007-2012). The wing patch size was larger in males than in females for all age-classes, and first-year individuals exhibited smaller wing patches than older birds, particularly in males. This trait also varied within the plumage-year at both population and individual level, with slight changes from the moulting period to the breeding season and a sharp decrease afterwards. In addition, patch size varied both between and within individuals across years. The daily mean temperature experienced in the month immediately prior to the moult (i.e. May) had a positive effect on male wing patch size. In females, however, no variable was found to satisfactorily explain wing patch variation. Despite being a dynamic trait throughout the moults, baseline and adjusted repeatabilities indicated a moderately high consistency for white wing patch size in both sexes. Therefore, the white wing patch in stonechats is a dynamic trait that changes throughout individuals’ lives, but is also a consistent trait at the individual level. These results indicate that this depigmented patch could convey information about both the long-term quality and the current state of individuals, harmonizing the existence of intra-individual changes in the size of sexual traits with its potential role as a genetic quality indicator.