Impact of extreme environmental conditions: Foraging behaviour and trophic ecology responses of a diving seabird, the common diving petrel

• Published in: Progress in Oceanography
• Main Authors: Fromant, Aymeric, Delord, Karine, Bost, Charles-André, Eizenberg, Yonina, Botha, Jonathan, Cherel, Yves, Bustamante, Paco, Gardner, Brett, Brault-Favrou, Maud, Lec'Hvien, Arnaud, Arnould, John P.Y.
• Other Authors: School of Life and Environmental Sciences, Deakin University Burwood, Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Marine Apex Predator Research Unit (MAPRU) Port Elizabeth, South Africa, Nelson Mandela University Port Elizabeth, LIttoral ENvironnement et Sociétés (LIENSs), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), Institut universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Werribee Open Range Zoo
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: Habitat modelling; Stable isotopes; GPS tracking; Inter-annual variation; Pelecanoides urinatrix; Marine heatwave; [SDV.BA.ZV]Life Sciences [q-bio]/Animal biology/Vertebrate Zoology; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Southern Ocean
• Online Access: https://hal.science/hal-03342136; https://hal.science/hal-03342136/document; https://hal.science/hal-03342136/file/Fromant%20et%20al%202021%20PROGRESS.pdf; https://doi.org/10.1016/j.pocean.2021.102676

International audience The reproductive success of birds is strongly driven by environmental conditions at different time scales. Thus, during periods of low food availability, breeding success is constrained by the ability of adults to adapt their foraging effort and feeding behaviour to maintain regular incubation shifts and chick provisioning. However, while large seabirds can buffer disruptions in prey availability, the ecophysiological constraints of smaller species may limit their behavioural flexibility. By combining information on at-sea movements, foraging habitat, trophic niche, and breeding success, this study evaluated the effects of intense variability in oceanographic conditions on common diving petrels (Pelecanoides urinatrix) at the northern extent of their range in south-eastern Australia during four consecutive breeding seasons. Unusually low breeding success (6 and 0%) was observed during two years with intense heatwave events, which were associated with higher foraging effort (foraging trips twice longer) and a substantial shift in trophic niche (lower blood δ15N values). These findings suggest that common diving petrels in Bass Strait may have reached a critical threshold above which buffering the effects of environmental variability on their reproductive output is not possible. The clear cascading impacts that marine heatwaves have on zooplankton feeders illustrate the profound bottom-up effect induced by such extreme environmental variations, and suggest strong impact on higher-trophic levels. The wide, circumpolar breeding distribution of the common diving petrel, and its high sensitivity to variations in oceanographic conditions, suggest that this species may be a suitable model to study short-term and long-term behavioural responses to the effects of climate change throughout the Southern Ocean.