Biparental Care and Nesting Success of the Swallow-tailed Cotinga in Northwestern Bolivia

Abstract

I studied the breeding biology, parental care, and nesting success of the Bolivian Swallow-tailed Cotinga (Phibalura flavirostris boliviana) in Aten, northwestern Bolivia, from October 2005 to February 2006. The incubation period ranged from 17 to 19 days and the nestling period was 25 to 30 days. Swallow-tailed Cotingas appeared to be monogamous during the entire nesting stage, from nest construction to fledging of nestlings, based on 10 nests with focal observations. Each parent took care of the nest every hour during the incubation period, but males spent more time at this activity than females. Both parents spent equal time taking care of the young during the nestling period. Nest care decreased as nestlings developed, the provisioning rate of parents increased, and length of foraging trips increased. The probability of daily survival between the nestling (0.9773) and incubation periods (0.9455) was not statistically significant; overall nesting success was low (20%). This work is the first detailed report of the nesting of this species in Bolivia.