The survival-reproduction association becomes stronger when conditions are good.
Positive covariations between survival and reproductive performance (S-R covariation) are generally interpreted in the context of fixed or dynamic demographic heterogeneity (i.e. persistent differences between individuals, or dynamic variation in resource acquisition), but the processes underlying covariations are still unknown. We used multi-event modelling to investigate how environmental and individual features influence S-R covariation patterns in a long-lived seabird, the Monteiro's storm petrel (Oceanodroma monteiroi). Our analysis reveals that a strong positive association between individual breeding success and subsequent survival occurs only when conditions are favourable to reproduction (in favourable years, in high-quality nests and in nest-faithful breeders). This finding reflects differences in the main causes of breeding failure and mortality under favourable and unfavourable conditions, which in turn lead to distinct patterns of S-R covariation. We suggest, in particular, that resource-related sources of demographic heterogeneity do not generate a strong S-R covariation, in contrast with hidden and unpredictable sources of variation.
Muséum National d'Histoire Naturelle, UMR 7204 Sorbonne Universités-MNHN-CNRS-UPMC, CP51, 55 Rue Buffon, Paris 75005, France arobert@mnhn.fr.
Alexandre
A
Robert
RSPB Centre for Conservation Science, UK Headquarters, The Lodge, Sandy, Bedfordshire SG19 2DL, UK.
Mark
M
Bolton
Muséum National d'Histoire Naturelle, UMR 7204 Sorbonne Universités-MNHN-CNRS-UPMC, CP51, 55 Rue Buffon, Paris 75005, France.
Frédéric
F
Jiguet
MARE (Marine and Environmental Science Centre), IMAR (Institute of Marine Research) and LARSyS Associated Lab, Departamento de Oceanografia e Pescas, Universidade dos Açores, Horta, Açores 9901-862, Portugal Cabinet Vétérinaire, 8 Avenue de la Reine Nathalie, Biarritz 64200, France.
Joël
J
Bried
D000818:Animals; D001394:Azores; D001717:Birds / Q000502:physiology*; D004777:Environment; D005260:Female; D008136:Longevity; D008297:Male; D008954:Models, Biological; D009425:Nesting Behavior; D012098:Reproduction / Q000502:physiology*
Oceanodroma monteiroi; demographic heterogeneity; individual quality; long-lived seabird; multi-event modelling; nest fidelity