Modelling bushfly populations.
The basic features of the population dynamics of Musca vetustissima Wlk. in Australia have previously been elucidated from field observations and some laboratory experiments. They include repopulation of study areas by immigration each spring, effects of larval feeding conditions and weather on fecundity and survival, and a few regulatory mechanisms. For an understanding of the roles of these components in the population dynamics of the fly, a simulation model provides a useful synthesis. This paper presents such a model for the fly in study areas in south-eastern Australia, and its biological acceptability is considered. Experience with the model shows that the features included generally suffice to reproduce the patterns of observed data. It also shows the existence of a critical date in spring before which immature survival is low and any immigration events have little bearing on the later population for the season. After that date, however, the next immigration generally determines the main features of subsequent patterns of abundance.