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This article discusses the influence of phenology-related intraseasonal asynchrony on metapopulation dynamics and stability. As the part played by intraseasonal asynchrony is as yet unclear and poorly described, greater account of it should be taken in both metapopulation research and conservation practice. The subpopulations of the Parnassius mnemosyne metapopulation studied here are strongly isolated because of the phenological shift between them, despite the relatively small physical distances between them. This isolation is the result of a significant temporal shift in the species' flight periods in the main metapopulation centers: in some seasons its flight times in the different subpopulations did not overlap at all. The predicted results of such strong intraseasonal asynchrony are not altogether clear. On the one hand, they reduce the vulnerability of the entire metapopulation to the effects of short-term random disasters. On the other, the ever-greater isolation of subpopulations may cause the metapopulation to become a nonequilibrium one, which will have a serious impact on its long-term survival., (© 2018 Institute of Zoology, Chinese Academy of Sciences.)

Terrestrial gastropods are keenly sensitive to changes in vegetation structure owing to their dependence on moisture. For this reason, low survivorship and recolonisation are to be expected after a fire. The fire described in this paper probably started as a result of the deliberate spring burning of vegetation that got out of control. Analysis of the data collected immediately after the fire does not reveal significant differences in the numbers of snails between habitats. This suggests that there are no refugia for this population: no vegetation-related refugium was confirmed. After the fire, snail numbers were found to have crashed, but the slight increase during the season could have been an indication of incipient recovery. Because the population of this species was consistently small, no differences in survivorship between habitats, regardless of their type, were discernible. The effects of the fire on this population in the River Nida Inland Delta were devastating: while it did survive the fire, its numbers fell sharply, by as much as two orders of magnitude. [ABSTRACT FROM AUTHOR]