Date of Award


Document Type

Honors Project

Degree Name

Bachelor of Science


Biological Sciences

Department Chair or Program Director

Dolby, Andrew S.

First Advisor

Dolby, Andrew S.

Second Advisor

O'Dell, Deborah A.

Third Advisor

Barra, Rosemary

Major or Concentration



Birds have a protective physiological response to stress, which consists of three main components: the hormonal response, the immune response and the intracellular response. This study evaluates the effects of acute distress due to capture and handling on plasma corticosterone (CORT) and heterophil/lymphocyte ratios (H/L) , physiological indicators of the hormonal and immune components of the stress response in the Tufted Titmouse (Baeolophus bicolor), as well as the relationship between the two biomarkers. These stress indicators are currently used in both basic and applied avian research. But their relationship with each other and their responses to specific stressors such as capture and handling have been little studied outside of research limited to work with poultry. The time between the initial moment of capture and blood collection was varied to evaluate the effect of handling time on CORT and H/L. CORT was positively correlated with handling time, and no correlation was found between H/L and handling time. No correlation was found for the within-subject relationship between CORT and H/L after the variation of CORT values owing to the effect of handling was removed. The variation of CORT due to capture and handling corresponds with previous research demonstrating that CORT values obtained more than 2 or 3 minutes after capture are no longer reliable baseline measurements indicative of environmental stress as opposed to handling stress. The resistance of H/L to the effect of capture and handling within handling times typical of avian field research supports it as a more useful tool in measuring chronic stress in birds.

Included in

Biology Commons