Population ecology Earlier colony arrival but no trend in hatching timing in two congeneric seabirds (Uria spp.) across the North Atlantic

• Published in: Biology Letters
• Main Authors: Merkel, Benjamin, Descamps, Sébastien, Yoccoz, Nigel, G, Danielsen, Jóhannis, Daunt, Francis, Erikstad, Kjell, E, Ezhov, Aleksey, V, Grémillet, David, Gavrilo, Maria, Lorentsen, Svein-Håkon, Reiertsen, Tone, K, Steen, Harald, Systad, Geir, H, Lindberg Þórarinsson, Þorkell, Wanless, Sarah, Strøm, Hallvard
• Other Authors: Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Centre for Ecology and Hydrology Edinburgh (CEH), Natural Environment Research Council (NERC), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD France-Sud )-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: Subject Areas: behaviour; ecology Keywords: guillemots; murres; pre-laying period; timing of egg-laying; Uria aalge; Uria lomvia; [SDE]Environmental Sciences; North Atlantic; uria
• Online Access: https://hal.science/hal-02328876; https://hal.science/hal-02328876/document; https://hal.science/hal-02328876/file/Merkel%20et%20al.%202019.pdf; https://doi.org/10.1098/rsbl.2019.0634

International audience A global analysis recently showed that seabird breeding phenology (as the timing of egg-laying and hatching) does not, on average, respond to temperature changes or advance with time (Keogan et al. 2018 Nat. Clim. Change 8, 313-318). This group, the most threatened of all birds, is therefore prone to spatio-temporal mismatches with their food resources. Yet, other aspects of the breeding phenology may also have a marked influence on breeding success , such as the arrival date of adults at the breeding site following winter migration. Here, we used a large tracking dataset of two congeneric seabirds breeding in 14 colonies across 18°latitudes, to show that arrival date at the colony was highly variable between colonies and species (ranging 80 days) and advanced 1.4 days/year while timing of egg-laying remained unchanged, resulting in an increasing pre-laying duration between 2009 and 2018. Thus, we demonstrate that potentially not all components of seabird breeding phenology are insensitive to changing environmental conditions.