Meeting Abstract
Modulation of respiratory physiology is part of the acute physiological response to stress. As respiratory rate has been shown to be repeatable within individuals over time, it has been increasingly used to characterize an individual’s coping style. However, it remains unclear whether respiratory rate can be used to assess the activity of the hypothalamic-pituitary-adrenal axis in free-living animals. In our study, we addressed this question by investigating the link between changes in respiratory rate and plasma corticosterone levels during a capture-restraint protocol in the migratory and resident subspecies of the White-crowned Sparrow (Zonotrichia leucophrys gambelii, Z.l. nuttalli, respectively). Birds were sampled at 10, 30 and 60 minutes post-capture during different stages of their annual cycle. In general, plasma corticosterone level increased following capture, whereas respiratory rate decreased over the same period of captivity. Respiratory rate showed subspecies-specific relationship with plasma levels of corticosterone, exhibiting significant negative correlation in the resident subspecies and no correlation in the migratory subspecies. Our results suggest that respiratory rate may be useful as a noninvasive substitute to plasma corticosterone in a capture-restraint protocol in some species but the relationship has to be validated first.
