ENDOCRINE-MEDIATED ORGANIZATIONAL EFFECTS ON PERSONALITY AND STRESS IN NAZCA BOOBIES

Nazca boobies (Sula granti) are socially and genetically monogamous, long-lived, ground-nesting, pelagic seabirds that have been the subject of recent behavioral and endocrine research due to two aspects of their life-history: obligate siblicide, and maltreatment of nestlings by unrelated non-breeding adults. The frequency of maltreatment as a nestling predicts future adult maltreatment behavior in a "cycle of violence", similar to that observed in humans. The research described here builds upon this previous work to investigate potential endocrine organization of this behavior and other physiological and behavioral traits of the Nazca booby. At the nestling stage, maltreatment causes transient surges in circulating corticosterone concentration ([CORT], the primary avian stress hormone), but no change in baseline [CORT] or testosterone, implicating short, but dramatic, hypothalamic-pituitary-adrenal (HPA) axis stress responses in organization of maltreatment behavior. Adult Nazca boobies exhibit personality traits on which early-life organizational effects could act: Gardening (anxiety-related movement of nest materials), Shaking (anxiety-related rotary movements), and Aggression. These traits and several aspects of the CORT stress response are consistently expressed at the individual level, across several years in adults. Nestling maltreatment experience, growth rate, and siblicide experience predict the frequency of anxiety-related behaviors displayed and the CORT stress response in Nazca booby adults. This research includes the longest analysis to date of organizational effects in a wholly wild, free-living animal, and detects long-term effects of maltreatment that are strikingly similar to those observed in humans, suggesting conservation of response to early life trauma between avian and mammalian taxa.

Grantor dc:publisher

Wake Forest University

Year dc:date.issued

2014

Author dc:creator

• Grace, Jacquelyn K.

• Behavioral Syndrome

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/10339/39247

OAI identifier oai:identifier

oai:wakespace.lib.wfu.edu:10339/39247