Eresus kollari (Araneae: Eresidae) calls for heathland management
Northwest Europe’s largest heather-dominated sandy habitats are located in the nature reserve Lu¨neburgerHeide, Germany. Yet, even these appear to be losing their ability to support some of their stenotopic species such as theladybird spider, Eresus kollari Rossi 1846, and are thus becoming increasingly important for the preservation of thesespecies. The habitat requirements of this endangered spider species were investigated in order to obtain data that will helpstabilize the last remnants of the species’ population in northwest Germany. Several heathland habitats were surveyed bypitfall trapping during the mate-search period of the males. Two statistical methods were applied: logistic reg…
Saproxylic beetle assemblages of three managed oak woodlands in the Eastern Mediterranean
Oak woodlands belong to the natural vegetation in most Mediterranean regions but have suffered from a long history of woodland devastation and overgrazing. The remaining woodlands have been managed in different ways, and we expected this to have effects on the fauna associated with trees. We investigated three different sites in the Eastern Mediterranean with flight-interception traps to analyse the impact of woodland management on dead wood and tree structures and the relevance for saproxylic beetle assemblages. Our results show significant differences in trunk diameter, stein density and dead wood diversity between the three sites. Old oaks in semi-open woodland are characterised by diver…
Conservation of threatened habitat types under future climate change – Lessons from plant-distribution models and current extinction trends in southern Germany
A higher risk of future range losses as a result of climate change is expected to be one of the main drivers of extinction trends in vascular plants occurring in habitat types of high conservation value. Nevertheless, the impact of the climate changes of the last 60 years on the current distribution and extinction patterns of plants is still largely unclear. We applied species distribution models to study the impact of environmental variables (climate, soil conditions, land cover, topography), on the current distribution of 18 vascular plant species characteristic of three threatened habitat types in southern Germany: (i) xero-thermophilous vegetation, (ii) mesophilous mountain grasslands (…
Saproxylic beetle assemblages in the Mediterranean region:Impact of forest management on richness and structure
Forests cover almost 30% of the Mediterranean region today, yet forest management activities have influenced structure and composition of both natural and planted forests. To date no study has been conducted to evaluate the impact of forest management on saproxylic beetle assemblages, although it is known that the Mediterranean is a biodiversity hotspot with a long-lasting human pressure on natural habitats. We provide an overview of saproxylic beetle assemblages of three forest types (mature Pinus halepensis forests, mature Pinus brutia forests, young Quercus calliprinos forests) in the East Mediterranean region using a one-year sample from 12 forest plots located in the north of Israel. T…
Determinants and Congruence of Species Richness Patterns across Multiple Taxonomic Groups on a Regional Scale
Applying multiple generalized regression models, we studied spatial patterns in species richness for different taxonomic groups (amphibians, reptiles, grasshoppers, plants, mosses) within the German federal state Rhineland-Palatinate (RP). We aimed (1) to detect their centres of richness, (2) to rate the influence of climatic and land-use parameters on spatial patterns, and (3) to test whether patterns are congruent between taxonomic groups in RP. Centres of species richness differed between taxonomic groups and overall richness was the highest in the valleys of large rivers and in different areas of southern RP. Climatic parameters strongly correlated with richness in all taxa whereas land…
Incorporating classified dispersal assumptions in predictive distribution models – A case study with grasshoppers and bush-crickets
Abstract Current and future species distributions depend on environmental conditions, but the ability of species to shift their range boundaries or to expand their distribution ranges in response to global change also depends on their dispersal capacity. Dispersal capacity, however, has often been neglected in previous studies that either assumed no-dispersal or full dispersal, both of which are unrealistic for most taxa. The aims of this study are (i) to identify the predictors of the present spatial distribution on a regional scale for 13 grasshoppers and bush-crickets, and (ii) to derive predictions of their future distributions under climate change by applying different dispersal capaci…
Poleward range expansion without a southern contraction in the ground beetle Agonum viridicupreum (Coleoptera, Carabidae)
We investigated the extent of poleward shifts in the distribution range of Agonum viridicupreum due to climate change in the western Palaearctic. Species' records were obtained from extensive literature sources as well as from collections, and consistent amateur entomologists' recordings. Within the general geographic range of the species, we analyzed in detail two parts of both, the northern and southern distribution range boundaries: (1 and 2) north-western Germany (leading or high-latitude edge), (3) Israel and (4) southern Italy (rear or low-latitude edge). Temporal changes in the occurrence data of the species indicated a northward shift of the leading edge of a minimum of 100 km withi…