Parental foraging strategies and feeding of nestlings in Common Redstart Phoenicurus phoenicurus

Abstract

Spatial foraging activity and feeding of broods was studied in nine pairs of Common Redstart (Phoenicurus phoenicurus) breeding in nest boxes in pine forest. The effect of nestling age on feeding rate was not significant. The number of feedings per chick was similar in small and medium size broods but decreased in the largest broods. Feeding rates in individual pairs did not differ between males and females. Mean nest visit duration were longer for females. Incubation of the youngest chicks was probably the cause of sig-nificant decrease of length of feeding visits by females during the chicks' growth. The proportion of foraging techniques was different between males and females, and changed during a nestlings' life. Males foraged predominantly by perching (passive foraging mode) throughout the whole breeding period. Females also foraged mostly by perching, but with younger broods they frequently used an active foraging mode of foliage glean-ing. The active foraging mode for younger broods could be either compensation of forag-ing efficiency for the time spent brooding, or caused by differences in prey selection at dif-ferent nestling ages, or active foraging does not pay off in the exploited habitat around the nest at the end of breeding.