Summary

Description

A major component of a species fitness is its ability to utilize time effectively. Through the process of natural selection a species becomes efficient at organizing its activities to suit habitat, temperature, competition, and the availability of food. In an area such as the Harney Basin, where temperatures may rise an fall 45 degrees Fahrenheit in a 24 hour period, time budgeting is especially important. A bird must organize its time so as to minimize water and energy loss maintaining body temperature , yet still being efficient when feeding. To exemplify this time budgeting two species were studies the Says Phoebe and the western Kingbird. Two general questions were considered: 1 What effect does the time of day have on the patterns of activity and habitat utilization of these two species, and 2 What effects does caring for nestlings have on the activity patterns of two very similar species.