Breeding status influences timing but not duration of moult in the Northern Fulmar Fulmarus glacialis

We thank Orkney Islands Council for access to Eynhallow and all the fieldworkers involved in deployment and recovery of the GLS tags and colony monitoring. All ringing work was carried out under permit from the BTO. We are grateful to James Fox of Migrate Technologies for recovering data from GLS loggers which would not download, and Richard Phillips and Janet Silk of BAS for advice on GLS analysis. Lucy Quinn was supported by a NERC Studentship and additional funding to support fieldwork was gratefully received from Talisman Energy (UK) Ltd. Additional support for loggers and analysis was provided through the SEATRACK project, which is funded by the Norwegian Ministry of Climate and Environment, the Norwegian Ministry of Foreign Affairs and the Norwegian Oil and Gas Association.Peer reviewedPostprin

Eye Region Surface Temperature and Corticosterone Response to Acute Stress in a High-Arctic Seabird, the Little Auk

Measuring changes in surface body temperature (specifically in eye-region) in vertebrates using infrared thermography is increasingly applied for detection of the stress reaction. Here we investigated the relationship between the eye-region temperature (TEYE; measured with infrared thermography), the corticosterone level in blood (CORT; stress indicator in birds), and some covariates (ambient temperature, humidity, and sex/body size) in a High-Arctic seabird, the Little Auk Alle alle. The birds responded to the capture-restrain protocol (blood sampling at the moment of capturing, and after 30 min of restrain) by a significant TEYE and CORT increase. However, the strength of the TEYE and CORT response to acute stress were not correlated. It confirms the results of a recent study on other species and all together indicates that infrared thermography is a useful, non-invasive measure of hypothalamic-pituitary-adrenal (HPA) axis reactivity under acute activation, but it might not be a suitable proxy for natural variation of circulating glucocorticoid levels

Vocal interactions of breeding partners predict duration of incubation bout in an Artic seabird

International audienceIn species with biparental care, coordination of parental activities can have important fitness consequences. However, specific behavioral mechanism allowing the coordination of breeding partners remains largely unexplored. Prevalence of biparental care in seabirds makes this group particularly interesting for investigation of behavioral underpinnings of parental coordination. Here, we examined vocal behavior at the nest site of breeding partners and its role in shaping their parental share during incubation in the little auk (Alle alle). We evaluated two hypotheses related to the mechanisms involved in parental coordination: (1) behavioral adjustment, where a parent adjusts its effort according to the preceding effort of its partner and (2) vocal negotiation, where effort is adjusted based on information exchanged during the preceding vocal interaction. We found that little auk partners equally share their incubation time, although, duration of nest attendance is highly variable. No immediate reciprocity between partners in the time allocated to parental activity was observed as predicted by behavioral adjustment. However, nest attendance appeared to be related to the vocal interaction between partners during turn-taking. The duration of a given attendance was positively associated to the pair's vocal activity and amount of vocal overlap occurring during turn-taking at the nest. Our results suggest a role of vocalization for coordinating between breeding pairs, providing a potential mechanism for the communication of information enabling this complex interaction. Vokale Interaktionen zwischen Brutpartnern bestimmen die Dauer der Inkubationsphasen bei einem arktischen SeevogelBei Vogelarten mit biparentaler Brutpflege, d. h. gemeinsame Brutpflege durch beide Elternteile, kann die Koordinierung des elterlichen Investments wichtige Auswirkungen auf die Fitness haben. Die spezifischen Verhaltensmechanismen, die die Synchronisierung der Brutpartner erm and ouml;glichen, sind jedoch noch gr and ouml;ss tenteils unerforscht. Die H and auml;ufigkeit der biparentalen Brutpflege bei Seev and ouml;geln macht diese Gruppe besonders interessant f and uuml;r die Untersuchung von Verhaltensweisen, die der Koordination der Elterntiere zugrunde liegen. Wir untersuchten hier das Rufverhalten der Brutpartner am Nest und dessen Rolle bei der Aufteilung der elterlichen Brutpflege w and auml;hrend der Brutzeit beim Krabbentaucher (Alle alle). Wir pr and uuml;ften zwei Hypothesen zu den Mechanismen, die an der Koordination zwischen den Elterntieren beteiligt sind: 1) Verhaltensanpassung, d. h. ein Elternteil passt sein Investment Einsatz an den vorangegangenen Einsatz seines Partners an, und 2) Abstimmung and uuml;ber Rufe (engl. ,,vocal negotiation"), d. h. der Bebr and uuml;tungseinsatz wird auf Grundlage des Informationsaustausches w and auml;hrend der vorangegangenen Rufinteraktion angepasst. Wir fanden heraus, dass Krabbentaucherpartner ihre Brutzeit gleichm and auml;ss ig untereinander aufteilen, auch wenn die Zeit am Nest stark variiert. Es wurde keine unmittelbare Wechselseitigkeit zwischen den Elternteilen in Bezug auf die Zeit, die f and uuml;r die elterliche F and uuml;rsorge aufgewendet wird, beobachtet, wie es die Hypothese der Verhaltensanpassung voraussagt. Die Anwesenheit am Nest schien jedoch mit der vokalen Interaktion der Elterntiere w and auml;hrend der Abl and ouml;sung am Nest verbunden zu sein. Die Dauer der Anwesenheit am Nest stand in einem positiven Zusammenhang mit der Rufaktivit and auml;t des Paares sowie mit dem Ausma ss an and Uuml;berschneidungen von Rufen w and auml;hrend der Abl and ouml;sung am Nest. Unsere Ergebnisse lassen vermuten, dass Rufen bei der Koordinierung zwischen den Brutpartnern eine Rolle spielt und einen potenziellen Mechanismus f and uuml;r den Informationsaustausch darstellt, der diese komplexe Interaktion erm and ouml;glicht

Post-foraging in-colony behaviour of a central-place foraging seabird

International audienceStudies on time allocation of various activities are crucial to understand which behavioural strategy is the most profitable in a given context, and so why animals behave in a particular way. Such investigations usually focus on a time window when the studied activity is performed, often neglecting how the time devoted to focal activity affects time allocation to following-up behaviours, while that may have its own fitness consequences. In this study, we examined time allocation into three post-foraging activities (entering the nest with food, nest attendance, and colony attendance) in a small seabird species, the little auk (Alle alle). Since little auks alternate foraging trips of different duration (short and long) and purpose (offspring feeding and primarily self-feeding, respectively) we expected that duration of the following up in-colony activities would also vary, being longer after a long absence in the colony (because of greater need of reassessment of the current predation pressure and social interactions in the colony, and re-establishing the bond with the offspring and/or partner and/or neighbours after longer absence). We found that it was not always the case, as time allocation of the post-foraging in-colony activities was primarily year- and sex-specific. It highlights the need to consider year and sex effects in studies of behavioural ecology, as not doing so may lead to spurious conclusions. Interestingly, and despite a great inter-individual variation in time allocation in the post-foraging in-colony activities, little auk individuals were quite repeatable in their behavioural performance, which suggests these activities may reflect birds behavioural profile. Overall, post-foraging in-colony activity of the little auk, although not much dependent on duration/type of the preceding foraging flights, varies with respect to year and sex, and as such may be a proxy of behavioural plasticity of the population

A keystone avian predator faces elevated energy expenditure in a warming Arctic

International audienceClimate change is transforming bioenergetic landscapes, challenging behavioral and physiological coping mechanisms. A critical question involves whether animals can adjust behavioral patterns and energy expenditure to stabilize fitness given reconfiguration of resource bases, or whether limits to plasticity ultimately compromise energy balance. In the Arctic, rapidly warming temperatures are transforming food webs, making Arctic organisms strong models for understanding biological implications of climate change-related environmental variability. We examined plasticity in the daily energy expenditure (DEE) of an Arctic seabird, the little auk (Alle alle) in response to variability in climate change-sensitive drivers of resource availability, sea surface temperature (SST) and sea ice coverage (SIC), and tested the hypothesis that energetic ceilings and exposure to mercury, an important neurotoxin and endocrine disrupter in marine ecosystems, may limit scope for plasticity. To estimate DEE, we used accelerometer data obtained across years from two colonies exposed to distinct environmental conditions (Ukaleqarteq [UK], East Greenland; Hornsund [HS], Svalbard). We proceeded to model future changes in SST to predict energetic impacts. At UK, high flight costs linked to low SIC and high SST drove DEE from below to above 4 × basal metabolic rate (BMR), a proposed energetic threshold for breeding birds. However, DEE remained below 7 × BMR, an alternative threshold, and did not plateau. Birds at HS experienced higher, relatively invariable SST, and operated above 4 × BMR. Mercury exposure was unrelated to DEE, and fitness remained stable. Thus, plasticity in DEE currently buffers fitness, providing resiliency against climate change. Nevertheless, modeling suggests that continued warming of SST may promote accelerating increases in DEE, which may become unsustainable