Walking energetics during ontogeny in birds

A species is only successful if the young reach adulthood and reproduce, and to survive a bird must balance its energy budget within a limited metabolic scope. Locomotion is the most energetically expensive activity contributing to the daily energy budget of birds and can be affected by temperature and food availability (through changes in food intake/distance travelled ratio). Changes in the cost of locomotion may alter the total daily energy expenditure of a bird or use energy previously allocated to
another activity. When we think of bird locomotion we tend to focus on flight, however many adult birds walk to forage for food and newly hatched birds cannot fly. Furthermore, the young of precocial species are mobile from hatching and must be capable of walking immediately. Therefore, knowing the metabolic cost of walking in precocial juveniles is a fundamental to understanding the overall energetic constraints they operate within. Despite the importance of juvenile survival to species persistence, studies of walking energetics in juveniles are lacking.

This project will conduct a multi-species comparative analysis, combining field and laboratory experiments, into the metabolic cost of walking in hatchling to adult birds. It will also for the first time document and duplicate in the laboratory, natural walking speeds. Finally, the experimental data will be used to produce a predictive model of walking metabolic costs for a range of kinematics (movement), morphologies and developmental stages.