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Boreal peat bogs contain distinctive insects in addition to widely distributed generalists, including species restricted to bogs (tyrphobionts) and species characteristic of bogs but not confined to them (tyrphophiles). Bogs raised above the water table form characteristic habitat islands in southern boreal and temperate forest zones. Many bogs have persisted for hundreds and even thousands of years, preserving relict ecosystems related to subarctic biomes. The historical development and nature of individual bogs are reflected by differences among their insects, which are of great biogeographical and ecological interest. The environmental sensitivity of bogs also makes insects valuable as bioindicators. Moreover, few readily accessible bogs remain in a natural state. Given the scientific interest of bog insects and the fact that each relict bog habitat island is unique, further studies of the diversity of bog faunas are merited, and the conservation of these habitats should be strongly supported by entomologists.

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The relationship between fecundity and long-term adult fluctuations of 29 temperate noctuid moths was investigated and is explained in terms of the r- and K-selection strategies. The potential population growth rate per year (PGR) and the "rate of return to equilibrium" (sensu Pimm 1982) have been calculated and correlated with generation-to-generation fluctuations. A highly significant correlation was found between PGR and the coefficient of generation-to-generation variation. The r-strategy species possess the highest PGR, the highest generation-to-generation coefficient of variation and their larvae are polyphagous. Species with typical features of K-strategists exhibit the lowest PGR values and the lowest generation-to-generation coefficients of variation. Their larvae seem to be exclusively oligophagous.

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Spatial distribution of ground beetles and moths in the isolated Central European Mrtvyĺ uh bog was analyzed. The most stenotopic tyrphobiontic species (relicts restricted to the peat bog) of ground beetles (Coleoptera: Carabidae) and moths (Lepidoptera) are distributed according to a distinct ecological gradient between the bog margin (lagg) and the bog centre. The degree of habitat preference between the bog margin and centre is taxonomically specific and significant. A list of stenotopic species of high conservation value is given. Several tyrphobiontic species occur in the treeless bog centre only. The tyrphophilous and tyrphoneutral species are distributed in the peat bog mostly randomly, some of such species prefer bog margins. The migratory highly opportunistic moths from habitats outside the bog usually cross the treeless centre. Most of the ubiquitous tyrphoneutral and migratory moths represent the faunal component, which is a very temporary phenomenon only, not associated with the peat bog permanently. The conservation of insect biodiversity associated with isolated peat bogs depends on complete preservation of the edaphic ecological conditions of the fragile paleorefugial habitat island and its spatial structure.

The abundance of moths was monitored with light-traps in two sites in southern Bohemia, Cesk6 Bud~jovice for 22 years and in Cerniw for 9 years. In these sites, that are vastly different in environmental stability and predictability, stability of insect populations was studied. The amplitude of fluctuations in abundance of the insect populations, as measured by the coefficient of variation (CV), varied a great deal between species so that there was a large overlap between the two sites. Nevertheless there was a highly significant tendency for species at Cerni~, the more stable site, to have smaller values of CV, i.e., to be less fluctuating. Also in species co-occurring in the two sites, the CV at ~erni~ tended to be smaller. Trends in abundance of individual species over time, both increases and decreases, were common in both sites and did not differ between habitats. Environmental stability begets insect population stability in terms of the amplitude of the fluctuations, but trends in time occur irrespective of stability of the habitat.