It’s not all abundance: Detectability and accessibility of food also explain breeding investment in long-lived marine animals

• Published in: PLOS ONE
• Main Authors: Real, Enric, Oro, Daniel, Bertolero, Albert, Igual, José Manuel, Sanz-Aguilar, Ana, Genovart, Meritxell, Hidalgo, Manuel, Tavecchia, Giacomo
• Format: Article in Journal/Newspaper
• Language: English
• Published: Public Library of Science 2022
• Subjects: North Atlantic; North Atlantic oscillation
• Online Access: http://hdl.handle.net/10261/280380

Este artículo contiene 15 páginas, 3 tablas, 3 figuras. Large-scale climatic indices are extensively used as predictors of ecological processes, but the mechanisms and the spatio-temporal scales at which climatic indices influence these processes are often speculative. Here, we use long-term data to evaluate how a measure of individual breeding investment (the egg volume) of three long-lived and long-distancemigrating seabirds is influenced by i) a large-scale climatic index (the North Atlantic Oscillation) and ii) local-scale variables (food abundance, foraging conditions, and competition). Winter values of the North Atlantic Oscillation did not correlate with local-scale variables measured in spring, but surprisingly, both had a high predictive power of the temporal variability of the egg volume in the three study species, even though they have different life-history strategies. The importance of the winter North Atlantic Oscillation suggests carry-over effects of winter conditions on subsequent breeding investment. Interestingly, the most important local-scale variables measured in spring were associated with food detectability (foraging conditions) and the factors influencing its accessibility (foraging conditions and competition by density-dependence). Large-scale climatic indices may work better as predictors of foraging conditions when organisms perform long distance migrations, while localscale variables are more appropriate when foraging areas are more restricted (e.g. during the breeding season). Contrary to what is commonly assumed, food abundance does not directly translate into food intake and its detectability and accessibility should be considered in the study of food-related ecological processes. Funds were supplied by grants CGL2013-42203-R and CGL2017-85210-P (MCIU/AEI/FEDER, UE) respectively. The study also received funding from the European Commission’s Horizon 2020 Research and Innovation Program under Grant Agreement no. 634495 for the project Sci-ence, Technology, and Society ...