Supplement 1. Monte Carlo simulation of the life tables of two interacting Virginia opossum populations.

kanda sourcesink montecarlo.xls
kanda sourcesink montecarlo.csv
kanda sourcesink montecarlo vbcode.txt

kanda sourcesink montecarlo.xls uses Visual Basic coding to simulate a population with two interacting sub-populations. The starting female population sizes by age and habitat are input into the spreadsheet, along with the persistence, survival, and dispersal rates and their variability estimates for each age class in each habitat during each season.

NrStablize determines the number of calculation cycles (functionally years) the simulation runs before returning the population growth rate lambda (end population size/beginning population size).

NrTrials determines the number of simulations run. A frequency histogram is returned for the values of lambda, along with its average and 95% limit estimates.
Other variables are described in the VB code.

kanda sourcesink montecarlo.csv is a comma-delimited version of the "Parameters" worksheet in the xls model, parameterized with the "original" life-table estimates.
kanda sourcesink montecarlo vbcode.txt is a text file of the source code for the visual basic macro used in the xls model.