Meeting Abstract

79.1  Tuesday, Jan. 6  Response to gonadotropin-releasing hormone and behavior in female northern cardinals, (Cardinalis cardinalis). JAWOR, Jodie*; DEVRIES, Susan; University of Southern Mississippi jodie.jawor@usm.edu

In birds, testosterone (T) has been shown to have a strong influence on behavior. Testosterone can decrease paternal behavior and increase aggressive behavior in both sexes. Previous studies have used the physiological response to a gonadotropin-releasing hormone (GnRH) challenge as a proxy for the stimulation of the hypothalamic-pituitary-gonadal (HPG) axis that naturally occurs during aggressive interactions. Here we report on the T response of female northern cardinals to a standardized GnRH challenge during different time points in the pre-breeding and early breeding season. In 2008 we administered 40 GnRH challenges to female cardinals. Blood samples were collected pre- and post-challenge with a 30min period between collections to allow T elevation. Response to the GnRH challenge was compared to melanin-based ornamentation (face mask) and nestling feeding behavior. Overall, female cardinals responded to GnRH challenges with a measureable increase in T and this was most pronounced in the pre-breeding season. Face mask expression negatively co-varied with response to GnRH challenge only when females were feeding nestlings. However, feeding behavior positively co-varied with nestling feeding behavior. This research shows that female northern cardinals can respond to GnRH challenges with an increase in T, however this response varies over the season. We suggest that this may have a strong impact on aggressive behavior observed in this species and may influence parental behavior as well.