Data from: Long-term effective population size dynamics of an intensively monitored vertebrate population

Long-term genetic data from intensively monitored natural populations are important for understanding how effective population sizes (Ne) can vary over time. We therefore genotyped 1,622 common buzzard (Buteo buteo) chicks sampled over twelve consecutive years (2002–2013 inclusive) at 15 microsatellite loci. This dataset allowed us both to compare single-sample with temporal approaches and to explore temporal patterns in the effective number of parents that produced each cohorteffective population size (Ne) of the parental generation in relation to the observed population dynamics. We found reasonable consistency between linkage disequilibrium-based single-sample and temporal estimators, particularly during the latter half of the study, but no clear relationship between annual Ne estimates ((N_e ) ̂) and census sizes. We also documented a fourteen-fold increase in (N_e ) ̂ between 2008 and 2011, a period during which the census size doubled, probably reflecting a combination of higher adult survival and immigration from further afield. Our study thus reveals appreciable temporal heterogeneity in the effective population size of a natural vertebrate population, confirms the need for long-term studies, and cautions against drawing conclusions from a single sample.