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Simple Summary: Sugar baits are not only used to attract butterflies; they are also used to attract nocturnal moths. Similarly to most sampling techniques, the results of bait trapping are influenced by ambient conditions. In order to understand how bait trap catches depend on weather parameters, we performed a study in the north European forest zone using portable weather stations placed next to the traps. We found that the number of moths caught was strongly positively dependent on temperature and negatively dependent on air humidity. Diversity showed a similar dependence on temperature and humidity but was also negatively affected by air pressure and positively affected by the change of pressure during the night. Our findings help to interpret the results of quantitative insect trapping projects as they allow one to properly account for variability in weather conditions. Assemblages of insects need to be quantitatively sampled in the context of various research questions. Light trapping is the most widely used method for sampling nocturnal Lepidoptera. Attracting moths to sugar baits offers a viable alternative. However, this method is rarely used in professional research despite its popularity among amateur lepidopterists. As the activity of insects is strongly dependent on ambient conditions, the sensitivity of any trapping method to weather parameters needs to be known for the quantitative interpretation of trapping results. In the present paper, we report data on the weather dependence of moth catches obtained by automatic bait traps. The study was performed in Estonia, representing the European hemiboreal forest zone. Portable weather stations set up next to each of the traps were used for collecting weather data. Both abundance and diversity of the moths in the catches depended strongly positively on temperature and negatively on air humidity. Diversity was also negatively correlated with air pressure and positively with the change in pressure during the night. The results show that in situ recording of weather parameters in connection to insect trapping provides useful insights for the study of insect behaviour and the interpretation of the results of monitoring projects. [ABSTRACT FROM AUTHOR]

Human-induced changes in habitat amount and quality constitute the key driver behind negative trends in global biodiversity. Conservation actions must be based on solid knowledge of the factors affecting species richness in the remaining habitat fragments. Besides local characteristics, it is critical to consider a broader spatial context when evaluating habitat quality. Here we present an analysis of landscape-level determinants of butterfly species richness based on a country-wide survey in Estonia, representing the northern European forest zone. This study compares favourably to previous research in its scope (over 1200 systematically selected sites), and provides a relatively 'natural' reference point for the analyses based on areas with higher human population density. The number of butterfly species locally recorded was sought to be explained by variables describing the surroundings of the study sites at four spatial scales. The proportion of forest land was by far the strongest factor (positively) affecting the number of butterfly species recorded, followed by soil alkalinity. Notably, the effects of forest land area at the smallest (in a radius of 250 m) and largest (2000 m) spatial scales were partly independent of each other. The former likely reflects immediate habitat quality while the latter should be related to the colonisation-extinction balance in the metapopulation context. The correlates of anthropogenic pressure (e.g., urbanization, roads, agriculture) had little effect. The results highlight the key role of designing responsible forestry practices in the regional context of nature conservation. [ABSTRACT FROM AUTHOR]

Abstract: In North-East Estonia, considerable amounts of toxicants (e.g. polycyclic aromatic hydrocarbons (PAHs), phenols, heavy metals) leach into water bodies through discharges from the oil-shale industry. In addition, natural and anthropogenic hypoxic events in water bodies affect the health of aquatic organisms. Here we report a study on the combined effects of contaminated sediment and hypoxia on the physiology of gibel carp (Carssius auratus gibelio). We conducted a laboratory exposure study that involved exposure to polluted sediments from oil-shale industries (River Purtse) and sediments from a relatively clean environment (River Selja), together with sediments spiked with PAHs. The oxygen content (saturation vs. hypoxia (<2mg/L)) was changed to reflect hypoxia. A multi-biomarker approach was chosen to enable the combined effects to be assessed comprehensively and integratively. We used HPLC to measure the PAH concentration in sediment and fish muscle, fixed wavelength fluorescence (FF) analyses to indicate the presence of PAH metabolites in fish bile, and nuclear abnormalities in erythrocytes as markers of geno- and cyto-toxicity; and we monitored the change in body condition and measured EROD activity to indicate CYP1A induction. High levels of PAH conjugates in fish bile were found in the group exposed to the Purtse River sediment under hypoxia. The results suggested that induction of the CYP1A gene was modulated by hypoxia as well as by heavy metals. We found a correlation between several erythrocyte abnormalities (8-shaped nuclei and blebbed nuclei) and PAH metabolite content in fish. In conclusion, a measurable effect of pollution from the oil-shale industry on fish health parameters was clear under different oxygen levels. [Copyright &y& Elsevier]

• Temperate forests managed by logging retain their suitability for forest butterflies. • Landscape-level forest cover positively affects local butterfly species richness. • Different forest types contribute to the regional fauna in a complementary manner. • Maintaining forest heterogeneity is crucial for preserving butterfly diversity. The conservation of forest biodiversity is increasingly relying on forest landscapes managed for timber production. A precondition for successful biodiversity conservation in intensively managed landscapes is a good understanding of habitat- and landscape-level drivers of species diversity. In this study, we investigated the effects of habitat characteristics and landscape context on the species richness and composition of butterflies in temperate forest landscapes routinely managed by clear-cutting. Our focus was on forest-dependent species. Even though about a quarter of the entire butterfly fauna in Europe are associated with forest habitats, the drivers of their diversity are poorly known. We used data from an unprecedentedly extensive butterfly survey, conducted in more than 400 sites distributed across all major forest types in Estonia (Northern Europe). Our data indicate that, generally, forests harvested for timber production remain suitable as habitats for forest butterflies: across the study sites, we recorded almost the full complement of their total regional species richness. By far the most influential driver of local butterfly species richness in such forests appears to be the proportion of forest cover in the surrounding landscape. The species richness of forest butterflies starts to show signs of decline at remarkably high levels of forest cover in the landscape. Surprisingly, landscape-scale forest heterogeneity around study sites had no discernible effect on local species richness, the pattern plausibly resulting from low mobility of forest butterflies. The most important habitat-scale predictor of butterfly species richness was soil moisture, with butterfly communities being most species-rich in forests on soils of intermediate moisture. Different forest types contribute to the regional species pool of forest butterflies in a complementary manner. No single forest type alone provides habitat for the entire species pool: peaks of abundance of different species are distributed across multiple forest types. Accordingly, a substantial part of the variation in species assemblages could be attributed to characteristic soil conditions (moisture and pH) of different forest types. Our findings imply that both the extent and heterogeneity of forest landscapes are important for maintaining the diversity of forest butterflies at the landscape scale. [ABSTRACT FROM AUTHOR]

Research on evolutionary forces determining optimal body sizes has primarily relied on experimental evaluation of respective selective pressures. Accounting for among-species variation through application of phylogenetic comparative methods is a complementary although little used approach. It enables the direct association of body size values with particular environments. Using phylogenetically explicit comparative analyses, we show that small body size is associated with diurnal (rather than nocturnal) activity of adults among temperate species of the moth family Geometridae. The association of an exclusively adult trait with species-specific body size suggests that optimal body sizes are at least partly determined by the costs being a large adult, as opposed to the more frequently considered costs of attaining large size. It appears likely that size-selective predation by insectivorous birds is the primary factor responsible for selection against large body size in day-flying moths., (© 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2018 European Society For Evolutionary Biology.)