DensiPOPd Web Interactive: Software to investigate the impacts to density dependence by lead in bald eagles in the Northeast United States
Hanley, Brenda; Dhondt, André; Bunting, Elizabeth; Pokras, Mark; Hynes, Kevin; Forzán, María; Schuler, Krysten
Bald eagle populations rebounded in the Northeast United States in recent decades. The DensiPOPd software integrates veterinary data with a population matrix model to compare the real and hypothetical impacts of lead on the NE bald eagle population during the early and later windows of population recovery. The early window of recovery is defined as the period between 1990-2006, which includes the years just prior to the species’ delisting from the ESA (in 2007). The later window of recovery is defined as the period from 2002-2018. The DensiPOPd app allows the user to compare demographic properties between lead and non-lead conditions, between time windows, between the sexes, or 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 DensiPOPd 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 CounterPOPd app (https://doi.org/10.7298/0v1k-wq39.2).
This study was funded in part by the Morris Animal Foundation under Grant # D18ZO-103. This software has not been reviewed nor endorsed by the Foundation, and the views expressed in this software do not necessarily reflect the views of the Foundation, its officers, directors, affiliates or agents.
Lefkovitch matrix; recovery; resource management