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Learning to live with unloved others is crucial in the ecological crisis. Unloved wasps are feared and disliked for their sting. Understanding of their ecological importance is increasing, however. Human-wasp encounters are changing with environmental changes, and strategies for multispecies cohabitation are needed. This multispecies study highlights features of wasp biology affecting human-wasp encounters and analyzes how conflicted human-wasp relations could be mitigated. The geographical focus is Finland, in the Northern boreal region. Biological analysis specified spatiotemporal aspects affecting human-wasp encounters: human and wasp habitats and preferences overlap ubiquitously. From a media analysis, we identified contextual strategies for living with wasps: exterminating, repelling, relocating, and giving space. Wasps do not receive only bad press – human-wasp relations are diverse and contextual. Knowledge of wasp ecology may allow for cultivating response-ability in multispecies encounters. Media provides information and narratives that allow reinterpreting wasp “aggression” as a vulnerable multispecies condition. Human-wasp encounters are corporeal and often preferably avoided. Therefore, methods that allow developing intimacy without proximity may be used for reflecting on human-wasp relations. One such method is crocheting decoy wasp nests. Human-wasp encounters could be mitigated by species-specific strategies that assess the risk involved. However, developing such strategies is difficult because wasps are often confused with other black-and-yellow insects.

Parasitoids and predators can cause marked mortality in their host species. I studied the occurrence, abundance, and biology of the wasp nest beetle Metoecus paradoxus (Ripiphoridae), inhabiting the nests of the common wasp Vespula vulgaris (Vespidae) in Central Finland. I also compiled phenological data of the species in Finland. The proportion of parasitized nests was 80%. The abundance of the beetle was generally some tens of individuals (max. = 130) per nest, and the parasitism rate 1–18% of the sealed cells, which are typical for the species in temperate Europe. The beetle occurred in several combs but was absent or rare in the oldest and newest combs. Sex ratio was female biased. Females were larger than males, and individuals from large cells were larger than from small cells. Adult beetles were observed rather steadily from early August to late September. The study shows that M. paradoxus is a common inhabitant of V. vulgaris nests in Central Finland, but due to a low frequency of parasitized cells its impact on wasp populations is likely to be minor.

Understanding of species distribution, abundance and habitat affinities is crucial for red-list assessment, conservation and habitat management. In Central Finland, we studied Collembola in three habitat types, namely non-grazedmeadows, pastures and road verges using pitfall traps. Altogether, 9,630 Collembola individuals were recorded. These belonged to 12 families, 34 genera and 60 species. The number of specimens was clearly higher in meadows than in pastures or road verges. The number of species, however, was higher in meadows and road verges (40 and 39 species, respectively) than in pastures (33 species). The overall species number is comparable to other large-scale sampling schemes in similar habitats. We recorded a few abundant species (Spatulosminthurus flaviceps, Sminthurus viridis and Sminthurus nigromaculatus) that have been previously recorded from very different biotopes. In conclusion, biodiversity inventories of soil fauna, as well as other biota, should also include marginal habitats, which often host peculiar communities.

Questions Agricultural intensification has led to the decline of biodiverse meadows and other semi-natural grasslands. Road verges offer potential alternative habitats for meadow species, but they may not be suitable for all meadow species due to different soil properties, frequent disturbances, pollution or suboptimal management. Are the communities of vascular plants and bryophytes similar or dissimilar to those in mown or grazed meadows? What kind of species are associated with road verges, mown meadows or grazed meadows? How do the habitat types differ in their soil conditions and disturbance intensity? Location The study was conducted on 36 sites in Central Finland. Methods We compared the vascular plant and bryophyte flora and the habitat characteristics of road verges, mown meadows and grazed meadows. Results The community composition of both vascular plants and bryophytes differed among the habitat types. Many species occurred in all three habitat types, but several meadow specialists were absent or less frequent in the road verges. In contrast, road verges hosted more forest species and ruderal species, especially bryophytes. Road verges differed from meadows in their soil conditions. Conclusions We conclude that although road verges may host some species typical to meadows, their value as alternative habitats could be increased by improved soil preparation and vegetation management. Meanwhile, the continued decline of quality habitats for meadow species underscores the need to maintain, increase and improve meadow management.

Questions Aspen (Populus tremula) is declining in the old‐growth forests of boreal Fennoscandia. This threatens the numerous taxa that are dependent on old aspens, including many epiphytic lichens. Potential methods to aid epiphytic lichens on aspen are centered around treatments which affect the density of Norway spruce (Picea abies). In this study, we investigated how epiphytic lichen communities on aspen are affected by the variation of spruce density in the immediate vicinity of the focal aspen. Location Southern boreal forests in Finland. Methods We recorded the occurrence of lichens from 120 aspens in 12 semi‐natural forest sites. We used spruce basal area as the measure for spruce density. The selected aspens represented a gradient in spruce basal area in the vicinity of the aspen from 0 to 36 m2/ha. We also measured other tree‐ and stand‐level variables that are known to influence lichen occurrence. Results Lichen communities on aspen were affected by spruce density, stand age and bark pH. Both lichen species richness and the richness of red‐listed species were highest at an intermediate spruce density, and both increased with stand age. Lichen species richness was higher when bark pH was lower. Additionally, community composition was influenced the most by spruce density, followed by bark pH. Conclusions Our study highlights the detrimental effects of high spruce density on lichen diversity on aspens. This is caused by high spruce density resulting in low light availability. Lichen diversity on aspens was highest when spruce density was intermediate. Spruce thinning in aspen‐rich old‐growth forests can be helpful in ensuring the long‐term persistence of old‐growth lichens on aspen in protected forests. peerReviewed

According to ecology theory, isolated habitat fragments cannot maintain populations of specialized species. Yet, empirical evidence based on monitoring of the same fragments over time is still limited. We studied the colonization–extinction dynamics of eight wood-decaying fungal species in 16 old-growth forest fragments (Phellinus nigrolimitatusPhellinus ferrugineofuscus

Grassland biodiversity, including traditional rural biotopes maintained by traditional agricultural practices, has become threatened worldwide. Road verges have been suggested to be complementary or compensatory habitats for species inhabiting grasslands. Species co-occurrence patterns linked with species traits can be used to separate between the different mechanisms (stochasticity, environmental filtering, biotic interactions) behind community structure. Here, we study species co-occurrence networks and underlying mechanisms of ground beetle species (Carabidae) in three different managed grassland types (meadows, pastures, road verges, n = 12 in each type) in Central Finland. We aimed to find out whether road verges can be considered as compensatory to traditional rural biotopes (meadows and pastures). We found that stochasticity explained over 90% of the pairwise co-occurrences, and the non-random co-occurrences were best explained by environmental filtering, regardless of the grassland type. However, the identities and traits of the species showing non-random co-occurrences differed among the habitat types. Thus, environmental factors behind environmental filtering differ among the habitat types and are related to the site-specific characteristics and variation therein. This poses challenges to habitat management since the species’ response to management action may depend on the site-specific characteristics. Although road verges are not fully compensatory to meadows and pastures, the high similarity of species richness and the high level of shared species suggest that for carabids road verges may be corridors connecting the sparse network of the remaining traditional rural biotopes.

Tree species is one of the most important determinants of wood-inhabiting fungal community composition, yet its relationship with fungal reproductive and dispersal traits remains poorly understood. We studied fungal communities (total of 657 species) inhabiting broadleaved and coniferous dead wood (total of 192 logs) in 12 semi-natural boreal forests. We utilized a trait-based hierarchical joint species distribution model to examine how the relationship between dead wood quality and species occurrence correlates with reproductive and dispersal morphological traits. Broadleaved trees had higher species richness than conifers, due to discomycetoids and pyrenomycetoids specializing in them. Resupinate and pileate species were generally specialized in coniferous dead wood. Fungi inhabiting broadleaved trees had larger and more elongated spores than fungi in conifers. Spore size was larger and spore shape more spherical in species occupying large dead wood units. These results indicate the selective effect of dead wood quality, visible not only in species diversity, but also in reproductive and dispersal traits. (C) 2019 Elsevier Ltd and British Mycological Society. All rights reserved. peerReviewed

Limited knowledge of dispersal for most organisms hampers effective connectivity conservation in fragmented landscapes. In forest ecosystems, deadwood-dependent organisms (i.e., saproxylics) are negatively affected by forest management and degradation globally. We reviewed empirically established dispersal ecology of saproxylic insects and fungi. We focused on direct studies (e.g., mark-recapture, radiotelemetry), field experiments, and population genetic analyses. We found 2 somewhat opposite results. Based on direct methods and experiments, dispersal is limited to within a few kilometers, whereas genetic studies showed little genetic structure over tens of kilometers, which indicates long-distance dispersal. The extent of direct dispersal studies and field experiments was small and thus these studies could not have detected long-distance dispersal. Particularly for fungi, more studies at management-relevant scales (1-10 km) are needed. Genetic researchers used outdated markers, investigated few loci, and faced the inherent difficulties of inferring dispersal from genetic population structure. Although there were systematic and species-specific differences in dispersal ability (fungi are better dispersers than insects), it seems that for both groups colonization and establishment, not dispersal per se, are limiting their occurrence at management-relevant scales. Because most studies were on forest landscapes in Europe, particularly the boreal region, more data are needed from nonforested landscapes in which fragmentation effects are likely to be more pronounced. Given the potential for long-distance dispersal and the logical necessity of habitat area being a more fundamental landscape attribute than the spatial arrangement of habitat patches (i.e., connectivity sensu strict), retaining high-quality deadwood habitat is more important for saproxylic insects and fungi than explicit connectivity conservation in many cases.

“Unless we change our ways of producing food, insects as a whole will go down the path of extinction in a few decades.” or “Our work reveals dramatic rates of decline that may lead to the extinction of 40% of the world's insect species over the next few decades.” These are verbatim conclusions of the recent paper by Sánchez-Bayoa and Wyckhuys (2019) in Biological Conservation. Because of fundamental methodological flaws, their conclusions are unsubstantiated. Like noted by The Guardian, the conclusions of the paper were set out in unusually forceful terms for a peer-reviewed scientific paper. The current case has already seen corrections and withdrawals in print and social media. We are concerned that such development is eroding the importance of the biodiversity crisis, making the work of conservationists harder, and undermining the credibility of conservation science.

Anthropogenic environmental changes have resulted in biodiversity crisis. Although tropical rainforests are one of the global biodiversity hotspots, their biodiversity is still poorly known. Especially fungi are poorly represented in national Red Lists and conservation plans, despite their important role in ecosystem functioning. We studied wood-inhabiting fungi (polypores) in four areas within two Atlantic rainforest fragments in Southeast Brazil. Our aim was to investigate fungal substrate characteristics and community composition. Deadwood amount ranged from 27 to 82 m3/ha among the four study areas and altogether we recorded 53 polypore species. More species were observed in intermediate and late decay stages than in early decay stages, but other deadwood variables did not explain the occurrence of polypores. Similarity in polypore community composition within and among the areas was low. Dissimilarity originated mostly from species turnover from a transect and area to another, and no nestedness in species occurrence pattern was detected. Hence, the observed dissimilarity in community composition was probably a result of heterogeneity in forest composition and structure, instead of environmental gradients or substrate limitations. These results corroborate previous polypore studies from the Atlantic forest in that tropical polypores are specialists toward particular decay stages. To develop ecologically effective conservation program for tropical polypores, more studies are needed on their distribution and abundance globally. peerReviewed

Uneven-aged forest management has attained increasing popularity. It may benefit biodiversity, buffer against pests and abiotic damages, decrease runoff from clearcuts and improve recreational values. We studied how gap cuttings and single-tree selection cuttings influence browsing damage in spruce-dominated forests in south-central Finland. Overall, browsing damage was especially frequent in aspen and rowan, but also in birch. The larger the basal area left in harvesting, the lower the browsing pressure on birch and rowan; neither the harvesting method nor the seedling density had an independent effect on browsing damage. Although larger tree retention levels may reduce browsing damage, the regeneration and recruitment of shade-intolerant broadleaved trees may be compromised. peerReviewed

Aspen is a keystone species in boreal forests. The future of aspen in many conservation areas is threatened by ungulate browsing. Our aim was to study the effect of browsing on aspen regeneration and population structure in conservation areas in Central Finland, and the effect of surrounding landscape structure on browsing. Aspen density varied greatly among and within conservation areas. In about half of the conservation areas, middle-sized aspens were scarce or missing, which indicates heavy browsing in the recent past. In addition, the number of dead, large aspens in advanced decay stages were rare. Browsing pressure varied greatly among the areas, but on average, a bit more than half of the living aspens had been browsed. Landscape structure influenced browsing so that increasing proportion of farmland within 1 km and 3 km of the conservation areas decreased browsing pressure. The poor recruitment of aspen in many conservation areas jeopardizes the accumulation of large living and dead aspens. This means that many aspen-associated threatened species are in the risk of local extinction, unless aspen recruitment is enhanced by management. peerReviewed

Land-use and management are disturbance factors that have diverse effects on community composition and structure. In traditional rural grasslands, such as meadows and pastures, low-intensity management is maintained to enhance biodiversity. Maintenance of road verges, in turn, creates habitat, which may complement traditional rural grasslands. To evaluate the effect of low-intensity disturbance on insect communities, we characterized species abundance distributions (SAD) for Carabidae, Formicidae, and Heteroptera in three grassland types, which differed in management: meadows, pastures, and road verges. The shape of SAD was estimated with three parameters: abundance decay rate, dominance, and rarity. We compared the SAD shape among the grassland types and tested the effect of environmental heterogeneity (plant species richness) and disturbance intensity (trampling in pastures) on SADs. The shape of SADs did not differ among the grassland types but among the taxonomic groups instead. Abundance decay rate and dominance were larger for Formicidae, and rarity smaller, than for Carabidae and Heteroptera. For Carabidae and window-trapped Heteroptera, rarity increased with increasing plant species richness. For Formicidae, dominance increased with trampling intensity in pastures. Although the SAD shape remained largely unchanged, the identity of the dominant species tended to vary within and among grassland types. Our study shows that for a given taxonomic group, the SAD shape is similar across habitat types with low-intensity disturbances resulting from different management. This suggests that SADs respond primarily to the intensity of disturbance and thus could be best used in monitoring communities across strong disturbance and environmental gradients. Because taxonomic groups can inherently have different SADs, taxon-specific SADs for undisturbed communities must be empirically documented before the SAD shape can be used as an indicator of environmental change. Because the identity of the dominant species changes from management type to another, the SAD shape alone is not an adequate monitoring tool. peerReviewed

Wood-pastures are threatened biotopes in which trees and livestock grazing maintain high conservation values. However, browsing may threaten tree regeneration, whereas abandonment leads to tree encroachment. We studied the regeneration of trees in a grazed and abandoned boreal wood-pastures. In grazed sites, the density of young spruces (Picea abies) was high, while the density of young birches (Betula spp.) was very low. Sprucification can be prevented only by removing spruces. The number of young birches and pines (Pinus sylvestris) was correlated with the number of junipers (Juniperus communis), probably because thorny junipers protect palatable seedlings from browsing. In abandoned sites, deciduous trees and spruces regenerated abundantly. In the long term, both grazing and abandonment lead to changes in tree species compositions and low diversity wood-pastures. Landscape scale planning and disturbance dynamics are needed for the creation of new wood-pastures and the maintenance of all pasture types within the landscape. peerReviewed

Dead wood profile of a forest is a useful tool for describing forest characteristics and assessing forest disturbance history. Nevertheless, there are few studies on dead wood profiles, including both coarse and fine dead wood, and on the effect of sampling intensity on the dead wood estimates. In a semi-natural boreal forest, we measured every dead wood item over 2 cm in diameter from 80 study plots. From eight plots, we further recorded dead wood items below 2 cm in diameter. Based on these data we constructed the full dead wood profile, i.e. the overall number of dead wood items and their distribution among different tree species, volumes of different size and decay stage categories. We discovered that while the number of small dead wood items was immense, their number dropped drastically from the diameter below 1 cm to diameters 2–3 cm. Different tree species had notably different abundance-diameter distribution patterns: spruce dead wood comprised most strikingly the smallest diameter fractions, whereas aspen dead wood comprised a larger share of large-diameter items. Most of the dead wood volume constituted of large pieces (>10 cm in diameter), and 62% of volume was birch. The variation in the dead wood estimates was small for the numerically dominant tree species and smallest diameter categories, but high for the sub-dominant tree species and larger size categories. In conclusion, the more the focus is on rare tree species and large dead wood items, the more comprehensive should the sampling be. Published by The Finnish Society of Forest Science. Licenced under CC BY-SA 4.0

Basidiomes of polypore fungi host many insects. Yet systematic information about insect assemblages from most fungal species is lacking. We studied the insect community associated with the wood-decaying fungus Inonotus radiatus (Sowerby: Fr.) P. Karst. (Hymenochaetales). More specifically, we studied the effect of successional stage and weight of basidiomes, as well as shore exposition (north or south), on species richness and composition, as well as occurrence and abundance of the most abundant fungivores. Basidiomes were collected from riparian forests at five lakes in Sweden. Insects were reared out from the basidiomes in the laboratory. A total of 5645 adult insect individuals of 117 taxa were obtained. Among these, 2782 specimens of 36 taxa use Inonotus radiatus basidiomes as breeding habitat. Eight species of parasitic wasps were new to Sweden. The most abundant fungivore was Ennearthron cornutum (Ciidae), which is a generalist breeding in many polypore species. Based on our material and lit...

Impaired ecosystems are converted back to natural ecosystems or some other target stage by means of restoration and management. Due to their agricultural legacy, afforested fields might be valuable compensatory habitats for rare fungal species that require nutrient-rich forest soils. Using a large-scale field experiment in Finland, we studied community composition of macrofungi (agarics and boletes) on former fields, which had been afforested as monocultures 20 years ago using native spruce Picea abies, pine Pinus sylvestris, and birch Betula pendula. We studied the effect of soil quality, tree species, and site on community composition and structure. Many nutrient-demanding as well as rare fungal species were recorded, particularly from pine and spruce plots. Pine plots supported more nutrient-demanding fungi than birch plots. There was no relationship between soil pH, bulk density, P, N, or Ca, and species richness of nutrient-demanding fungi. Fungal community composition was more similar within sites than among sites for all tree species. Among sites, spruce plots had the smallest fungal species turnover, and birch plots largest. Within sites, however, fungal species turnover from plot to plot was similar among tree species. Our results indicate that tree species has a relatively mild influence on species composition of fungi after 20 years of succession. Interestingly, the results show that afforested fields can be valuable complementary habitats for rare, red-listed, and nutrient-demanding fungal species. Field afforestation is a potential conservation tool that could be used to complement the poor representation of rare habitat types in highly fragmented protected area networks.

Impaired natural ecosystems, such as agricultural lands, are restored toward original or other target stage. Because the long agricultural history has changed the physical, chemical and biological features of the soil, afforested fields can harbor novel species assemblages and interactions. Our overall aim was to quantify the diversity of ground beetles and ants in early successional afforested fields. In a large scale field experiment, we compared plots that had been afforested 25 years ago by planting monocultures of birch, pine or spruce trees. A total of 4080 carabid individuals representing 41 species, and 131,933 ant individuals representing 15 species were recorded. Both the carabid and ant assemblage included forest and open-habitat species, but were dominated by generalists, which is typical for early successional habitats. Tree species had a strong influence on carabid and ant assemblages. Species composition among pine plots was more homogeneous than among spruce or birch plots. The diversity of ground beetles and ants increased from pine to spruce to birch plots, most likely due to positive influence of leaf litter. Our results indicate that early successional afforested fields can harbor species rich arthropod assemblages. The diversity and species composition of these assemblages are influenced by tree species, already at early successional stages, and are likely to become more prominent as succession proceeds. Thus, the tree species used in afforestation is one important factor for consideration, if field afforestation has biodiversity objectives.

Uusekosysteemit ovat kaikkialla. On arvioitu, että noin kolmasosa maaekosysteemeistä on uusia. Uusekosysteemeistä on kirjoitettu satoja tieteellisiä artikkeleita kymmenen viime vuoden aikana. Mutta ovatko hylätyt soramontut, ojitetut suot ja metsitetyt pellot uusekosysteemejä? Onko uusekosysteemejä ylipäätään olemassa? Määrittelykamppailu käy kiivaana soveltavassa ekologiassa. Samalla käytännön toimija seuraa sanailua ymmällään ja pohtii, tarvitseeko hän edes koko käsitettä.

Former agricultural lands may host peculiar biota, because agriculture activities have changed the physical, chemical and biological features of the soil; however, biodiversity in afforested fields is poorly known. The aim of this study was to investigate the diversity of ground-dwelling true bugs (Heteroptera) in early successional afforested fields in central Finland. We used a large-scale field experiment, in which agricultural land had been afforested 25 years ago by planting monocultures of birch, pine and spruce trees. Pitfall traps caught a total of 224 heteropteran individuals representing 20 species. The community was numerically dominated by Lygaeidae, Drymus brunneus being the most abundant species. Birch plots hosted about the double the number of individuals and species in spruce and pine plots. The near-threatened Teloleuca pellucens (Saldidae) was recorded from a birch plot. Although T. pellucens is suggested to require old-growth forests, our observation indicates that the species can occur also in other types of forests. In conclusion, more studies on Heteroptera in different environments are needed to better understand their distribution, abundance and habitat affinities. nonPeerReviewed

Many protected areas have a long history of human intervention before being protected. In protected forests, the past land use has reduced the amount of natural structures, which are crucial substrates for thousands of species. We evaluate the short-term ecological effect of forest restoration (dead wood creation) on conifer-associated saproxylic (dead-wood dependent) beetles. More specifically, we analyze the effect of dead wood creation on the number of beetle species and individuals 1 and 5 years after restoration in spruce and pine forests, using a large-scale monitoring network over Finland. The number of saproxylic beetle species and individuals was larger at restored than at control plots both 1 and 5 years after restoration in both spruce and pine forests. Community composition in restored plots was different from control plots 1 year after restoration, but had returned towards the control plot composition 5 years after restoration, while control plots remained largely unchanged. Both in spruce and pine forests, there were more red-listed and rare saproxylic beetles in restored than in control plots 1 and 5 years after restoration. Our results indicate that restoration has an overall positive influence on saproxylic beetle diversity immediately after dead wood creation, but this effect is rather short-lived. Long term monitoring of restored dead wood is crucial in investigating successional pathways as well as biotic communities in advanced decay stages, and in fully evaluating the ecological effect of dead wood creation as a forest restoration measure.

SUMMARYThe International Union for Conservation of Nature (IUCN) Red List provides a globally-recognized evaluation of the conservation status of species, with the aim of catalysing appropriate conservation action. However, in some parts of the world, species data may be lacking or insufficient to predict risk status. If species with shared ecological or life history characteristics also tend to share their risk of extinction, then ecological or life history characteristics may be used to predict which species may be at risk, although perhaps not yet classified as such by the IUCN. Statistical models may be a means to determine whether there are non-threatened or unclassified species that share the characteristics of threatened species, however there are no data on which model might be most appropriate or whether multiple models should be used. In this paper, three types of statistical models, namely regression trees, logistic regression and discriminant function analysis are compared using data on the ecological characteristics of Finnish lepidopterans (butterflies and moths). Overall, logistic regression performed slightly better than discriminant function analysis in predicting species status, and both outperformed regression trees. Uncertainty in species classification suggests that multiple analyses should be performed and particular attention devoted to those species for which the methods disagree. Such standard statistical methods may be a valuable additional tool in assessing the likely threat status of a species where there is a paucity of abundance data.

The alarming rate of ecosystem degradation has raised the need for ecological restoration throughout different biomes and continents. North European forests may appear as one of the least vulnerable ecosystems from a global perspective, since forest cover is not rapidly decreasing and many ecosystem services remain at high level. However, extensive areas of northern forests are heavily exploited and have lost a major part of their biodiversity value. There is a strong requirement to restore these areas towards a more natural condition in order to meet the targets of the Convention on Biological Diversity. Several northern countries are now taking up this challenge by restoring forest biodiversity with increasing intensity. The ecology and biodiversity of boreal forests are relatively well understood making them a good model for restoration activities in many other forest ecosystems. Here we introduce northern forests as an ecosystem, discuss the historical and recent human impact and provide a brief status report on the ecological restoration projects and research already conducted there. Based on this discussion, we argue that before any restoration actions commence, the ecology of the target ecosystem should be established with the need for restoration carefully assessed and the outcome properly monitored. Finally, we identify the most important challenges that need to be solved in order to carry out efficient restoration with powerful and long-term positive impacts on biodiversity: coping with unpredictability, maintaining connectivity in time and space, assessment of functionality, management of conflicting interests and social restrictions and ensuring adequate funding.

Aim Macroecological patterns have mainly been depicted as atemporal, withexisting research covering only short time periods. One fundamental pattern inmacroecology is the interspecific relationship between local abundance andregional range size, which is generally considered to be positively linear. Here,we examine structural details of the relationship between abundance and rangesize in cyclic populations of small mammals and its long-term temporal varia-tion.Location Finland.Methods We analysed 39 years of trapping data of Rodentia and Soricomor-pha collected in field and forest habitats across Finland. Abundance was mea-sured as the mean population density of individuals, and range size as thenumber of grid cells occupied and sample occupancy. Data were analysed usinglinear mixed models.Results The relationship between mean local density and sample occupancywas generally linear, whereas the relationship between density and the numberof grid cells occupied was generally curvilinear (U-shaped) for both habitats,being negative for species with small range sizes and positive for species withlarger ranges. The curvilinearity was temporally consistent in both habitats.Main conclusions The interspecific relationship between abundance andrange size varies depending on how range size is measured. Interestingly, thecurvilinear relationship between density and range size was found in an assem-blage in which many of the species have fluctuating (cyclic) populations.Future research on abundance–range size relationships should focus on long-term temporal variation to better understand the underlying mechanisms andto develop macroecological theory.KeywordsAbundance–distribution relationship, macroecology, population cyclicity, Rod-entia, Soricomorpha, synchrony, temporal variation.INTRODUCTIONThe interspecific relationship between local population den-sity and range size is a fundamental pattern in macroecology.Although this relationship varies considerably in sign, slopeand shape across realms, biogeographical regions, habitats,taxa and spatial scales, a positive log-linear relationshipbetween the two is generally observed (Blackburn et al.,2006; Borregaard & Rahbek, 2010).Macroecology can be defined as the analysis of emergentstatistical properties of large data sets (Brown, 1995) or asthe analysis of data from large geographical areas and longtemporal scales (Gaston et al., 2000; Fisher et al., 2010).Macroecological patterns have predominantly been depictedas atemporal, which may potentially obscure their dynamicsand inadvertently conceal the identity of underlying pro-cesses (Fisher et al., 2010). For example, one-year snapshotdata cannot reveal temporal consistency, and pooled datamay only represent emergent, average patterns (Turner et al.,1987; Kerr et al., 2007). Particularly regarding abundance–range size relationships over large geographical scales, tempo-ral analyses are in their infancy (but see Collins & Glenn,1194

Habitat loss, fragmentation, and degradation are the main threats to biodiversity. Human activities also create new habitat types that might fulfil ecological requirements for a variety of species. This study investigates whether the vegetation clearing (=shrub and tree cutting) on drained mire patches on power line rights-of-ways (ROWs) keep plant communities in an early successional stage and thus provide habitats for mire specialist and non-mire butterflies. It was further studied what would be the optimal clearing interval in terms of butterfly species richness and abundance. The results show that tree height, especially the height of birch, increases linearly over the 7-year period following vegetation clearing. The average birch height had a significant negative relationship with the species richness of mire and non-mire butterflies. The clearing interval had a significant curvilinear relationship with the abundance of both mire and non-mire butterflies, such that the highest abundances were documented two to four growing seasons after the clearing, which would hence be the ecologically optimal vegetation clearing cycle. In general, vegetation management on power line ROWs enhance favourable conditions for butterflies and may maintain habitats for mire-dependent butterflies, even on drained mires.

Habitat loss is one of the greatest threats for biodiversity. In Finland, two thirds of natural mires have been drained for silviculture, which transforms open wetlands into dense forests. However, vegetation management of power line rights-of-way (ROW) maintain the drained mires as open areas. The aim of this study was to determine the effect of the power line ROW vegetation management on butterfly abundance, species richness and community structure by comparing the managed power line ROWs to unmanaged drained control sites and to natural mires. The species richness or abundance of mire butterflies did not differ between the power line ROWs and natural mires. In contrast, both species richness and abundance of butterflies was low on the unmanaged control sites. Tree canopy cover had a negative effect on mire butterflies and this is most likely related to changes in microclimate. The results indicate that the active vegetation removal in the power line ROWs maintain alternative habitats for mire butterflies; yet, the power line ROWs cannot substitute the natural mires.

Empirical evidence does not fully support the universal nature of the positive interspecific abundance—distribution relationship. We have earlier documented a negative relationship for butterfly species in Finland, but recently our view was again challenged using a small subset of Finnish butterflies as apparent evidence. Here we scrutinize the critique and identify some general conceptual challenges in analyses of interspecific abundance—distribution relationships. We identify the common problem that the abundance—distribution studies include only a small subset of species, and thus reveal only sample characteristics, not overall patterns in complete assemblages. Small subsets of species are also unlikely to have sufficient power to reveal nonlinear relationships. Second, varying definitions of abundance, especially the practice of using a single point estimate to describe average density, further spur the empirical evidence for the abundance—distribution relationship. To get theoretically relevant resul...

1. In order to be effective custodians of biodiversity, one must understand what ecological characteristics predispose species to population decline, range contraction, and, eventually, to extinction. 2. The present paper analyses distribution change (area of occupancy) and range shift (extent and direction) of the threatened and non-threatened butterfly species in Finland, and identifies species-specific ecological characteristics promoting changes in distribution and range. 3. Overall, the range of butterflies has shifted along the climatic isotherms, suggesting that climate change has influenced species’ ranges. Interestingly, though, threatened species have moved very little and not to any consistent direction. 4. The most obvious pattern observed is that ecological specialisation, be it at larval or at adult stage, promotes distribution decline. The analysis further revealed that poor dispersal ability and large body size predispose species to distribution decline. 5. Species ecological traits influence their susceptibility to distribution change and range shift. Thus, as a result of climate change, biological communities may become over-represented by highly dispersive generalists. It is argued that with the kind of ecological information provided here, managers should become proactive and initiate the necessary measures for conservation of species when their populations are still viable instead of reacting only to the imminent extinction risk when it already may be too late.

Large-scale natural disturbances pose challenges for the management of protected areas and may have undesirable consequences for commercial plantations nearby. A storm, which felled nearly 10 000 m 3 of spruce forest in the Osaby nature reserve in southern Sweden, allowed us to study the subsequent population development of the spruce bark beetle (Ips typographus L.). Two summers after the storm, an exceptionally high proportion (74%) of wind-felled trees had been successfully colonized by the bark beetle, and all living spruce trees had been killed. On standing trees, colonization density was three times higher, and reproductive success one-fourth, that on wind-felled trees. The negative relationship between colonization density and reproductive success indicates that intra-specific competition is one of the main mechanisms reducing I. typographus population growth when the beetles switch from wind-felled to standing trees after storm disturbances. Indeed, there was no significant difference in beetle production between wind-felled and standing trees. Furthermore, there were no differences in colonization density, reproductive success or production at different heights in standing trees; however, a higher proportion of the new adults emerged at the tree-tops rather than lower down before overwintering. Our results also demonstrate that a large proportion (ca. 50%) of the 1. typographus population that developed in the storm-fell area apparently overwintered under the bark of standing trees.

Here we quantitatively summarize the conservation ecology of one group of dead-wood-dependent organisms, the polyporous fungi, in boreal Europe. At the substrate scale, the decay stage is the strongest determinant of species richness, with large (>20 cm diameter) downed logs hosting more species than other dead-wood types. At the stand scale, the amount of dead wood is the strongest determinant of polypore species richness; the minimum average amount of dead wood for the occurrence of rare polypores appears to be 20–40 m 3 /ha. Species-area analysis shows that in mature boreal forests species accumulation levels off at around 20–30 ha. This leads us to suggest a heuristic 20/20/20 rule of thumb: a 20 ha stand, with an average of 20 m 3 /ha of dead wood of which many are logs >20 cm, is likely to be the minimum for the ecologically justified conservation of polypore diversity at the stand scale in boreal Europe. Equally crucial for polypore diversity, however, is the current and historic extent of suitable habitats at the landscape scale. The time lag between the isolation of a habitat patch and the new equilibrium in the number or occurrence of species seems to be around 100–150 years, indicating that an extinction debt is likely to exist in recently isolated fragments. Only a few studies have addressed the ecological efficiency of the new, biodiversity-oriented forest management tools (retention trees, woodland key habitats). Despite this it seems that the traditional large conservation areas are the most effective means of polypore conservation.