title: The stress response is attenuated during inclement weather in parental, but not in pre-parental, Lapland longspurs (Calcarius lapponicus) breeding in the Low Arctic.
abstract: Birds breeding at high latitudes can be faced with extreme weather events throughout the breeding season. In response to environmental perturbations, vertebrates activate the hypothalamic-pituitary-adrenal (HPA) axis and synthesize corticosterone, which promotes changes in behavior and physiology to help the animal survive. The parental care hypothesis suggests that the HPA axis activity should be downregulated during the parental stage of breeding to prevent nest abandonment. However, it is unknown what happens to HPA axis activity in response to severe weather at the transition from the pre-parental to parental stages of breeding. We sampled baseline corticosterone levels and the time course of corticosterone elevation over 60min of restraint stress and assessed body condition and fat stores in Lapland longspurs (Calcarius lapponicus) breeding in the Low Arctic in the presence and absence of snowstorms. The results showed that during the pre-parental stage, HPA axis activity was up-regulated in response to snowstorms, with corticosterone levels continuing to increase through 60min of restraint. However, once birds were parental, HPA axis activity was unaffected by snowstorms and levels peaked at 10min. Fat levels and body condition did not change in response to snowstorms but fat levels declined in males during the pre-parental stage. These data suggest that the parental care hypothesis can be applied to severe storm events; parental birds restrained the activity of the HPA axis, likely to focus on the reproductive effort that is already underway, while pre-parental birds greatly upregulated HPA axis activity in response to snowstorms to maximize self-preservation.
authors.affiliation: Department of Neurobiology, Physiology and Behavior, University of California Davis, One Shields Avenue, Davis, CA 95616, USA. Electronic address: jskrause@ucdavis.edu.
authors.forename: Jesse S
authors.initials: JS
authors.lastname: Krause
authors.affiliation: Department of Neurobiology, Physiology and Behavior, University of California Davis, One Shields Avenue, Davis, CA 95616, USA.
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Pérez
authors.affiliation: Department of Neurobiology, Physiology and Behavior, University of California Davis, One Shields Avenue, Davis, CA 95616, USA.
authors.forename: Helen E
authors.initials: HE
authors.lastname: Chmura
authors.affiliation: The Roslin Institute, The Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush, Midlothian EH25 9RG, Scotland, UK.
authors.forename: Simone L
authors.initials: SL
authors.lastname: Meddle
authors.affiliation: New England Aquarium, Boston, MA, USA.
authors.forename: Kathleen E
authors.initials: KE
authors.lastname: Hunt
authors.affiliation: Department of Biological Sciences, Towson University, Towson, MD 21252, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Gough
authors.affiliation: Department of Biological Sciences, Towson University, Towson, MD 21252, USA; Department of Earth and Environmental Sciences, Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA.
authors.forename: Natalie
authors.initials: N
authors.lastname: Boelman
authors.affiliation: Department of Neurobiology, Physiology and Behavior, University of California Davis, One Shields Avenue, Davis, CA 95616, USA.
authors.forename: John C
authors.initials: JC
authors.lastname: Wingfield
mesh_terms: D000818:Animals; D001110:Arctic Regions; D001522:Behavior, Animal / Q000502:physiology; D003345:Corticosterone / Q000502:physiology; D005260:Female; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology; D008297:Male; D009425:Nesting Behavior / Q000502:physiology*; D046109:Passeriformes / Q000502:physiology*; D010913:Pituitary-Adrenal System / Q000502:physiology; D012098:Reproduction / Q000502:physiology*; D012621:Seasons; D013312:Stress, Physiological / Q000502:physiology*; D014887:Weather
chemical_list: D003345:Corticosterone
keywords: Corticosterone; HPA axis; Life history trade-offs; Parental care; Snowstorms; Stress