Data used for models presented in: The quantitative genetics of fitness in a wild seabird by Moiron M., Charmantier A. and Bouwhuis S. published in Evolution for information regarding the analyses, please contact mariamoironc@gmail.com for information regarding the data, please contact sandra.bouwhuis@ifv-vogelwarte.de if you'd like to use the data, please also contact sandra.bouwhuis@ifv-vogelwarte.de These data are part of those collected in an ongoing individual-based longitudinal population study additional data are likely to be available, and we are often very happy to collaborate provided that none of our own staff or students is working on a conflicting project Detailed information on data: ID: individual unique identifier YOH: year of hatching (i.e., cohort effects) year: year of breeding (i.e., of measurement) sex: sex of the individual (being 1 = males) age: age of the individual, measured in years after hatching (being 0 = hatching, 1= one year old, and so on) LRS_fl: total number of fledglings produced by a locally-born fledgling status: whether an individual was considered dead or alive at the end of the study period ARS: annual reproductive success measured as the number of fledglings that an individual produced each year between age 1 and last registration, assigning zeroes for years of skipped reproduction or registration, and for years prior to recruitment AAS: adult survival (1/0) to the following breeding season, measured every year from age 1 to last registration (inferring missing direct observations prior to recruitment from later observations)