  Populations are often subject to catastrophes that cause mass removal of
individuals. Many stochastic growth models have been considered to explain such
dynamics. Among the results reported, it has been considered whether dispersion
strategies, at times of catastrophes, increase the survival probability of the
population. In this paper, we contrast dispersion strategies comparing mean
extinction times of the population when extinction occurs almost surely. In
particular, we consider populations subject to binomial catastrophes, that is,
the population size is reduced according to a binomial law when a catastrophe
occurs. Our findings delineate the optimal strategy (dispersion or
non-dispersion) based on variations in model parameter values.
