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The European red click beetle, Elater ferrugineus L., is associated with wood mould in old hollow deciduous trees. As a result of severe habitat fragmentation caused by human disturbance, it is threatened throughout its distribution range. A new pheromone-based survey method, which is very efficient in detecting the species, was used in the present study to relate the occurrence of E. ferrugineus to the density of deciduous trees. The latter data were from a recently completed regional survey in SE Sweden recording >120,000 deciduous trees. The occurrence of E. ferrugineus increased with increasing amount of large hollow and large non-hollow trees in the surrounding landscape. Quercus robur (oak) was found to be the most important substrate for E. ferrugineus, whereas two groups of tree species (Carpinus betulus, Fagus sylvatica, Ulmus glabra, vs. Acer platanoides, Aesculus hippocastanum, Fraxinus excelsior, Tilia cordata) were less important but may be a complement to oak in sustaining populations of the beetle. The occurrence of E. ferrugineus was explained by the density of oaks at two different spatial scales, within the circle radii 327 m and 4658 m. In conclusion, priority should be given to oaks in conservation management of E. ferrugineus, and then to the deciduous trees in the genera listed above. Conservation planning at large spatial and temporal scales appears to be essential for long-term persistence of E. ferrugineus. We also show that occurrence models based on strategic sampling might result in pessimistic predictions. This study demonstrates how pheromone-based monitoring make insects excellent tools for sustained feedback to models for landscape conservation management.

The strongly increasing demand for biofuel from forests poses new challenges for biodiversity conservation. Methods that may combine biofuel production with conservation goals need to be tested for various forest types. One possible conservation-oriented management alternative is partial cutting of closed canopy oak-rich forests (may also be called conservation thinning). Such cutting may counteract succession and restore a semi-open canopy structure, which may favor epiphytes. We evaluated this possibility by surveying the epiphyte community of lichens and bryophytes on large oaks in 24 oak-rich temperate forests in southern Sweden. Treatment plots, and reference plots with no cutting, were surveyed before, and 6 years after cutting. In the treatment plots, about 25% of the basal area was harvested, and mainly small and intermediate sized successional trees were removed. We detected significant positive effects of partial cutting on species density for both lichens and bryophytes. The additional variation in light influx at tree level (after the cutting) could not explain the change in species density. The increase in density of lichen species was highest on oaks with small trunk diameter and on oaks with deep bark crevices. The pooled frequency of species of conservation concern increased after the cutting, but the change in species composition was weak; colonization events occurred over mean minimum distances of 63.5 m to the nearest potential source tree (n = 22 events and 9 species). Overall, we found significantly higher colonization rates, and significantly lower extinction rates per tree for lichens in the treatment plots. We conclude that partial cutting influenced epiphytes of large oaks positively, as was the case for several other organism groups at the same study sites (previous studies). A mild form of biofuel harvesting may represent sustainable resource-use in these forests, compatible with conservation. However, part of the forest should be kept unt, Funding Agencies|Swedish Energy Agency (STEM)||Swedish Research Council (VR)||foundation of C. Stenholm

Breeding performance of Black-throated Diver Gavia arctica was compared to water chemistry, light penetration and density of fish in 122 breeding lakes in Sweden with a total of 184 pairs (1.5 pairs per lake, about 3% of the national population). The breeding lakes were on average nutrient-poor, and 12% of them had a low buffering capacity (alkalinity <0.10 meq/l). Perch Perca fluviatilis, roach Rutilus rutilus and pike Esox lucius, three species characteristic for nutrient-poor lakes, were found in more than 90% of the lakes. Salmonid fish occurred in half of the lakes, compared to >90% of the fishing lakes used by Red-throated Diver. Reproduction was related to high abundance of Perch, and the survival of chicks to light penetration. Poor nutrient status in combination with low pH or alkalinity in approximatively 10% of the breeding lakes of Black-throated Diver and probably more than 30% of the fishing lakes of Red-throated Diver, indicate susceptibility of exposure to methylmercury. This finding should be considered in relation to recent reports of increased contents of mercury in freshwater fish., Water chemistry and the composition of fish stocks in the breeding lakes of Black-throated Diver Gavia arctica, and a comparison with the fishing lakes of Red-throated Diver Gavia stellata

Lichen cover and diversity was analysed on the dwarf shrub Helianthemum oelandicum (L.) Dum.Cours.at one site in the calcareous grassland of the area known as the 'Great Alvar' on the Island of Öland, Sweden. The age of 22 phorophytes was determined by ring counting and varied from 8 to 41 years and was accurately predicted by the root diameter. A total of 18 lichen species were found, with a range between 0 and 13 species per phorophyte. The number of lichen species on living H. oelandicum was correlated with the phorophyte age. The number of lichen species and their coverage was greater on dead compared with living phorophytes. The species number was also higher on thin branches compared with thick branches and roots and some of the species showed preferences for dead phorophytes, and for thin branches. This study of lichen colonization and growth on dwarf shrubs in relation to phorophyte age is a new application of herbchronology.