Parental care and external sexual characters in the Warbling Doradito (Pseudocolopteryx flaviventris)

CARDONI, D.A; PRETELLI, M.G.; ISACCH, J.P.; MADRID ENRIQUE; BALADRON ALEJANDRO; CHIARADIA NICOLAS

Journal of Ornithology

Springer

Año: 2017 vol. 158 p. 159 - 167

2193-7192

Biparental care is the dominant (81 %) form ofparental care in birds. The degree of sexual selection andthe resulting mating system and parental care type havebeen determined, in many cases, by inference from externalcharacters of sexual dimorphism. The lack of informationand the biological attributes of the tyrant flycatchers (e.g.,low sexual dimorphism) make it difficult to determinate theparental care roles in most species. Tyrant flycatcherscomprise a diverse bird family, but information on thereproductive behavior of many Tyrannid species is lacking.Our aim was to describe external sexual characters (morphologyand coloration) and determine the parental carebehavior at the nest in the Warbling Doradito (Pseudocolopteryxflaviventris), especially considering the potentialrole of sexual differences in relation to parental roles atnest. We studied the parental care behavior during twobreeding seasons. Parents were captured to take morphologicalmeasurements and a blood sample for molecularsex determination. We found that parental care in theWarbling Doradito was biparental biased toward females,where the incubation was performed exclusively byfemales and the 74 % of activities of nestling brooding andfeeding was performed by females. We also found sexualdifferences, slight in size and plumage, but more conspicuousin bill color. Despite the relatively slight sexualdichromatism of the Warbling Doradito, the parental carebehavior in the nest was biased towards females, and theassistance of males to nestlings was highly variable andwas not correlated with either clutch size or increasingnestling mass. Therefore, the evidence presented heresuggest that Pseudocolopteryx genus may have an unusualsocial system, otherwise uncommon in tyrannids.