Connecting the dots in databases of endangered species: a Bayesian hierarchical imputation strategy for missing Peary caribou (Rangifer tarandus pearyi) population data

•Modelling species at risk can be challenging due to incomplete datasets.•An imputation strategy is developed to reconstruct Peary caribou population trends.•Our imputation model reproduced more than 65% of the Peary caribou variability.•Estimates of population rates of change were robust with or without imputed data•Simple empirical models cannot accommodate the non-monotonic Peary caribou patterns.