Supplementary material from "Early mortality saves energy: estimating the energetic cost of excess offspring in a seabird" ...

• Main Authors: Vedder, Oscar, Zhang, He, Bouwhuis, Sandra
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: The Royal Society 2017
• Subjects: Common tern; Sterna hirundo
• Online Access: https://dx.doi.org/10.6084/m9.figshare.c.3679381; https://rs.figshare.com/collections/Supplementary_material_from_Early_mortality_saves_energy_estimating_the_energetic_cost_of_excess_offspring_in_a_seabird_/3679381

Offspring are often produced in excess as insurance against stochastic events or unpredictable resources. This strategy may result in high early-life mortality, yet age-specific mortality before offspring independence and its associated costs have rarely been quantified. In this study, we modelled age-specific survival from hatching to fledging using 24 years of data on hatching order (HO), growth and age of mortality of more than 15 000 common tern ( Sterna hirundo ) chicks. We found that mortality peaked directly after hatching, after which it declined rapidly. Mortality hazard was best described with the Gompertz function, and was higher with later HO, mainly due to differences in baseline mortality hazard, rather than age-dependent mortality. Based on allometric mass–metabolism relationships and detailed growth curves of starving chicks, we estimated that the average metabolizable energy intake of non-fledged chicks was only 8.7% of the metabolizable energy intake of successful chicks during the nestling ...