Foraging Efficiency and Parental Care in Colibri coruscans

Abstract

Time and energy budgets and estimates of foraging efficiencies were obtained for 2 C. coruscans. One of these was caring for 2 recently fledged young while territorial at flowers of Mutisia accuminata at an elevation of 3000 m in the Andes of Central Peru. Despite somewhat lower estimates of foraging efficiencies than for other nectarivores, parental care was accomplished without substantial increases in foraging time. Flycatching increased for the 1st week and subsequently declined; estimates of the efficiency of flycatching suggested values similar to using nectar as a food source. Calculations based on achieved foraging efficiency for 1 day suggested that the parent was not meeting all the energy requirements of herself and the 2 young. Foraging behavior suggested increased nectar intake by the parent before feeding young and the delivery of some of this nectar to the young. Increased flycatching should have been important in supplying energy. Failure by the parent to provide for all energy requirements of the young may have been important in forcing their independent foraging.