Meeting Abstract

10.1  Saturday, Jan. 4 08:00  How many measures are enough: using a broad approach to examine health in a community of free-living birds. WILCOXEN, TE*; HORN, DJ; HUBER, SJ; HOGAN, BM; HUBBLE, CN; KNOTT, MH; PLANTS, S; WASSENHOVE, SJ; Millikin University; Millikin University; Millikin University, Univ. of South Florida; Millikin University; Millikin University, Des Moines Univ.; Millikin University; Millikin Univeristy; Millikin University, Univ. of Illinois-Springfield twilcoxen@millikin.edu

Ecophysiologists are regularly searching for effective ways to determine the impacts of variable environmental conditions within habitats on the physiology of animals living in those habitats. Concerns surround the use of a single or small-set of metrics given the vast number of physiological processes with important regulatory functions in the body. Further, the repeatability of many of these measures within free-living individuals is often unknown and the time-course over which changes in environmental conditions are reflected in changes in physiology is often species and context specific. We conducted a 2-year, community-level study of over 2,200 free-living birds from 10 species of passerines and near-passerines and utilized many metrics to assess the health of the birds. Included in this assessment were measurements of baseline corticosterone, a body condition index from structural size and mass, hematocrit, feather quality, leukocyte counts, plasma protein levels, total antioxidant capacity, and four assays of innate immune function. There were many strong correlations among these metrics, allowing us to construct a consistent ‘health profile’ for many birds. In addition, among the many birds for which we had more than one capture record, repeatability was high for some measures but not for others. These correlations among multiple physiological products further our understanding of interacting physiological systems within free-living animals in variable environmental conditions.