Observations on incubation, nestling growth, and parental care of the orange-bellied euphonia euphonia xanthogaster

center dot We present the first observations of nestling growth and parental care behaviors in the Orange-bellied Euphonia Euphonia xanthogaster. We also add to the body of knowledge on clutch size, incubation, and fledgling periods and nest sanitation activities and present egg measurements from three E. x. quitensis and three E. x. brevirostris nests from Ecuador. Clutch sizes and nestling development were similar to those described for other Euphonia species, and eggs and nests followed previous descriptions for the species. The incubation period was 14 days and fledging approximately 21 days. We used 246 hours of recorded observations from two nests found in February of 2002 and 2006 in tropical montane forest near the Yanayacu Biological Station in Cosanga, Ecuador, to document feeding, parental care and sanitation behaviors. Recording at one nest began at the onset of incubation and continued through fledging, while the other was recorded after hatch and through fledging. Males were not observed to participate in incubation or brooding but participated significantly in feeding nestlings. Males alternated feeding visits with the female during the observed period, but females spent significantly more time at the nest, likely due to greater investment in brooding and nest sanitation. Both sexes were observed to make coordinated misdirection flights, with the male performing the majority. Females only performed misdirection flights after hatch.