Microhabitat Selection During Nesting of Hummingbirds in the Rocky Mountains

Abstract

The importance of nest location in reducing heat loss by radiation and convection is indicated by a preliminary examination of the nest sites of Broad—tailed and Calliope hummingbirds with regard to chilling nights in the Rocky Mountains. Radiation losses are estimated from surface temperatures. Nest diameter and weight increase as a function of time in the nesting season.