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1. Gypsy moth outbreaks cause severe defoliation in Holarctic forests, both in North America where it is invasive, and in its native range in Eurasia. Defoliation can hamper timber production and impact ecological communities and processes. Aerial insecticide applications are regularly performed in outbreak areas to mitigate economic losses. These operations can be financially costly and harmful to non-target species and may disrupt species interaction networks. However, replicated studies of the relative impacts of gypsy moth outbreaks and insecticide application on forest growth and animal communities are rare and have yet to be carried out in the species' indigenous range. 2. Here, we review the pathways in which gypsy moth outbreaks and the chemical control of these outbreaks affect forest ecosystems. We then present an experimental design established in South Central Germany in early 2019, aiming to study the ecological and economic consequences of gypsy moth eruptions and insecticide application in oak forests. The study's full factorial design comprises forest stands at high and low defoliation risk, either treated with tebufenozide or left unsprayed, within 12 experimental blocks. Measurements of forest growth and structure, tree mortality, gypsy moth density, and composition of lepidopteran, bird, bat, ground beetle, and canopy arthropod communities will be conducted for several years. 3. One-year intensive monitoring of gypsy moth populations and damage across the selected sites showed substantial differences in population density between plots at high and low defoliation risk and high efficacy of tebufenozide in suppressing gypsy moth populations in treated plots. In the first year of the experiment, gypsy moth density and defoliation in predicted outbreak plots differed strongly, confirming the This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Abstract. We studied the effects of global warming and rising temperatures on the ground beetle fauna of Bavarian beech forests using the space for time approach at two geographical scales. The first was a Bavarian-wide gradient of 50 plots in beech forests and the second a regional gradient in the Bavarian Forest in the mountains in eastern Bavaria consisting of 48 plots, which also included subalpine spruce forests. For purposes of validation, we used backdrop data from 413 additional plots all across Bavaria from a wide range of forest habitats. We found five species that would be favoured and six species that would be disadvantaged by rising temperatures in beech forests. For another five species the conditions within the gradient studied reach both their minimum and their maximum temperatures. As a consequence of increasing temperatures there will be winners and losers in these forests and the species composition of ground beetle communities will change. Approximately the same number of species is likely to profit as will be affected negatively. However, when considering the "global responsibility species" for Germany, the balance is negative. Species may react differently in different habitats and at different regional scales, which must be taken into consideration when applying the results.

The Carabus subgenus Hygrocarabus contains two taxa: C. variolosus and C. nodulosus, the species or subspecies status of which is handled far from uniform in the literature. Both taxa show a similar morphology, the shape of the tip of the aedeagus provides a reliable morphological marker for identification. We analysed two mitochondrial gene parts (COI-5’ and COI-3’) and a nuclear one (ITS2). High diversity was found showing specific geographical patterns. Introgressive hybridisation was detected but interpreted not as an argument for subspecies status because high genetic distances indicated that it must have taken place in former times. In a laboratory hybridisation experiment, the male did not accept the female of the other taxon, supporting the conclusion that these are separate species. A series of refuges was expected for the period of ice ages. Although only the taxon C. variolosus is listed in Annex II and IV of the EU Habitats Directive, C. nodulosus also falls under this listing, as at the time of including the species into the Annexes in 2004, the two taxa were considered subspecies and hence the listing would include both, independent of later taxonomic revisions.

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