From the simulated epidemic histories we gathered and analysed the following outputs: mean epidemic time, mean kit fox population persistence time, maximum and median number of E + I, and minimum and median N (adult female kit fox population size). Local extinction of kit foxes and disease occurs when N = 0 and E + I = 0, respectively. After confirming normality, we used paired t-tests to compare mean epidemic times that occurred using the actual, heterogeneous landscape versus a flat landscape in which K was constant across all quads. Given that an influx of juvenile S individuals could impact epidemic duration and magnitude, we also examined model outputs with varying birthrates. Because mange transmission among foxes has been reported to be frequency-dependent [39 (link)], we also compared model output for frequency (by dividing the transmission function by N) and DDT. Default parameters remained static across model runs except where noted to implement the analysis; each analysis was done by running the model for at least 10 trials and 4000 days.
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