Preformative molt in Neotropical Cardinalidae

Abstract

Neotropical Cardinalidae consists of 40 species in 10 genera that have diversified across the Americas. We provide quantitative information on the preformative molt of 21 Cardinalidae species of seven genera, plus one Thraupidae species placed within Cardinalidae until recently. From 155 preformative molt cards, we calculated molt extent estimates, computed frequencies of molt patterns, and summarized observed frequencies of wing-feather replacement in wing diagrams. We found 17 species with partial preformative molts, four species with eccentric preformative molts (outer but not inner primaries replaced), and one species with a complete preformative molt. Preformative molt extent and patterns were similar within Cardinalidae genera, including genera with Nearctic representatives, such as the complete preformative molt of Northern Cardinal Cardinalis cardinalis or the eccentric molt of Passerina buntings. Our results cover an important gap in the knowledge of the natural history of Cardinalidae, generate important criteria to determine the age of Neotropical Cardinalidae, and provide essential information to test hypotheses on the ecology and evolution of molt in this passerine family. Age determination; Bayesian bootstrapping; Molt extent; Molt patterns