The ClosedDensiPOPd software integrates veterinary data with a population matrix model to compare the real and hypothetical impacts of lead on a population of bald eagles in a hypothetically closed system during the early and later windows of population recovery. The early window of recovery is defined as the period when abundances were low, while the late window of recovery is defined as the period when abundances were high. A closed system does not allow for incoming nor outgoing dispersal, but it does allow for temporary migration. The ClosedDensiPOPd app allows the user to compare demographic properties between lead and non-lead conditions, between time windows, between the sexes, or between all three. Comparative demographic quantities include the annual abundances, bi-annual abundances, migration and dispersal, growth rates (asymptotic, transient, cumulative, and stochastic), stable stage distribution, reproductive value, survival rates, sensitivities, elasticities, damping ratios, convergence times, and more. The ClosedDensiPOPd app is programmed to compare a population of bald eagles with and without lead toxicosis, but the software may be modified to assess the population scale impact of other veterinary maladies. For similar analyses given the full time window of population recovery (1990-2018), please use the ClosedCounterPOPd app (https://doi.org/10.7298/q4t7-1y54).