Comparison of the probability of survival of a metapopulation in a network without (white bars) and with a permanent habitat (black bars) for the different scenarios (see Methods); ** indicates significant differences (P<0.0001, χ² test, d.f. = 199), ns means “non-significant”.

<p>Upper figures: synchronized environment; lower figures: non-synchronized environment. Figures on left: short-range dispersal; figures on right: long-range dispersal. Each diagram presents results for both low and high growth rates, and short (i.e. 0.2, LM) and long (i.e. 0.8, HM) range dispersal between habitats. Rate of immigration into the permanent habitat is 0.1 for HM and 0.7 for LM and from permanent to temporary habitats is 0.9 in all situations.