title: Modulation of heart rate response to acute stressors throughout the breeding season in the king penguin Aptenodytes patagonicus.
abstract: 'Fight-or-flight' stress responses allow animals to cope adaptively to sudden threats by mobilizing energy resources and priming the body for action. Because such responses can be costly and redirect behavior and energy from reproduction to survival, they are likely to be shaped by specific life-history stages, depending on the available energy resources and the commitment to reproduction. Here, we consider how heart rate (HR) responses to acute stressors are affected by the advancing breeding season in a colonial seabird, the king penguin (Aptenodytes patagonicus). We subjected 77 birds (44 males, 33 females) at various stages of incubation and chick-rearing to three experimental stressors (metal sound, distant approach and capture) known to vary both in their intensity and associated risk, and monitored their HR responses. Our results show that HR increase in response to acute stressors was progressively attenuated with the stage of breeding from incubation to chick-rearing. Stress responses did not vary according to nutritional status or seasonal timing (whether breeding was initiated early or late in the season), but were markedly lower during chick-rearing than during incubation. This pattern was obvious for all three stressors. We discuss how 'fight-or-flight' responses may be modulated by considering the energy commitment to breeding, nutritional status and reproductive value of the brood in breeding seabirds.
authors.affiliation: Université de Strasbourg, Institut Pluridisciplinaire Hubert Curien (IPHC), Département Ecologie, Physiologie et Ethologie (DEPE), 23 rue Becquerel, Strasbourg 67087, France CNRS, UMR7178, Strasbourg 67087, France Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE, 1919 route de Mende, Montpellier 34293, France vincent.viblanc@gmail.com.
authors.forename: Vincent A
authors.initials: VA
authors.lastname: Viblanc
authors.affiliation: Université de Strasbourg, Institut Pluridisciplinaire Hubert Curien (IPHC), Département Ecologie, Physiologie et Ethologie (DEPE), 23 rue Becquerel, Strasbourg 67087, France CNRS, UMR7178, Strasbourg 67087, France.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Smith
authors.affiliation: Université de Strasbourg, Institut Pluridisciplinaire Hubert Curien (IPHC), Département Ecologie, Physiologie et Ethologie (DEPE), 23 rue Becquerel, Strasbourg 67087, France CNRS, UMR7178, Strasbourg 67087, France.
authors.forename: Benoit
authors.initials: B
authors.lastname: Gineste
authors.affiliation: Université de Strasbourg, Institut Pluridisciplinaire Hubert Curien (IPHC), Département Ecologie, Physiologie et Ethologie (DEPE), 23 rue Becquerel, Strasbourg 67087, France CNRS, UMR7178, Strasbourg 67087, France.
authors.forename: Marion
authors.initials: M
authors.lastname: Kauffmann
authors.affiliation: Université de Strasbourg, Institut Pluridisciplinaire Hubert Curien (IPHC), Département Ecologie, Physiologie et Ethologie (DEPE), 23 rue Becquerel, Strasbourg 67087, France CNRS, UMR7178, Strasbourg 67087, France.
authors.forename: René
authors.initials: R
authors.lastname: Groscolas
mesh_terms: D000818:Animals; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D008297:Male; D008425:Maternal Behavior; D010332:Paternal Behavior; D012621:Seasons; D046429:Spheniscidae / Q000502:physiology*; D013312:Stress, Physiological
keywords: Acute stress; Energy cost; Fasting; Heart rate; Penguin; Reproductive value; Risk assessment; Seabird