Dear MARMAM colleagues, We are pleased to announce that the following paper is now available online: Enrico Pirotta, Leslie New, Alejandro Fernandez Ajó, K. C. Bierlich, Clara N. Bird, C. Loren Buck, Lisa Hildebrand, Kathleen E. Hunt, John Calambokidis, and Leigh G. Torres. Body size, nutritional state and endocrine state are associated with calving probability in a long-lived marine species. Journal of Animal Ecology. Abstract: 1 - Life-history performance of individuals in wildlife populations emerges from the interplay between the multiple processes that constitute an animal's health. Monitoring and modelling indicators of health can thus provide a way to assess and forecast the status of a population before its abundance changes. 2 - In this study, we develop a Bayesian state–space model that links multiple health indicators (representing energy, endocrine and morphometric status) and resulting female calving probability, using an 8-year dataset of repeated sightings, morphological measurements, faecal sampling and offspring observations of gray whales (*Eschrichtius robustus*) belonging to the Pacific Coast Feeding Group. 3 - Model results indicate that calving probability emerges from the combined effect of a female's structural body size and available energy reserves, while also showing a weak negative correlation with glucocorticoid levels prior to pregnancy. Assessment of population age structure suggests that the number of individuals in younger age classes is smaller than expected for a growing or a stable population, which, together with decreasing body size, could indicate an impending decline in this group. Model development was made possible by the collection of high-resolution, longitudinal data on individuals, although several mechanistic assumptions were imposed by the relatively short time series (8 years), influencing the results. 4 - Our modelling approach could inform similar efforts in other long-lived species where population dynamics cannot be easily monitored. Ultimately, models of wildlife health and vital rates can support assessments of the population-level consequences of multiple stressors, a key goal for management and conservation across systems and jurisdictions. Keywords: Bayesian state–space modelling, calving probability, early warning signals, gray whales, health, Pacific Coast Feeding Group, population consequences of disturbance. A PDF copy of the paper can be downloaded from: https://doi.org/10.1111/1365-2656.70068 Please do not hesitate to contact me for any questions regarding our work. Best Regards, Enrico Pirotta