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Background Protected areas (PA) are central to biodiversity, but their efficiency is challenged by human-induced habitat loss and fragmentation. In the Fennoscandian boreal region, forestry with clearcutting is a threat to biodiversity causing the loss of mature forest elements and deterioration of ecological processes in forest landscapes, ultimately affecting PAs via declined structural connectivity. This paper aims to (1) determine PAs with high, red-listed species concentrations; (2) estimate the change in forest habitat around these PAs on different spatial scales; and (3) determine if forest management intensity is higher around biologically most valuable PAs. Occurrences of red-listed forest-dwelling species in Finland were used to identify PAs harbouring these species and to produce site-specific importance indices. CORINE landcover data was used as a baseline for the distribution of forests to assess the cover of clear-cuttings from 2001 to 2019 with the Global Forest Change (GFC) data set in three buffer areas around the PAs with occurrences of red-listed species. Results The largest proportion of clear-cuts occurred in 1 km and 10 km buffers around the PAs in the southern and middle boreal zones, being ca. 20%. This indicates that the forest habitat is degrading fast at regional and landscape levels. On the positive side, the change in forest cover was lower around the biologically most important PAs compared to other PAs with red-listed species. Conclusions Open and free satellite-data based assessments of the cover and change of forests provide reliable estimates about the rates at which mature and old-growth forests are being converted into young managed ones in Finland mainly via clear-cuts on different scales around PAs. The rate of clear-cuts was lowest in adjacent buffer areas next to the most species-rich PAs, which provides opportunities for biodiversity conservation efforts to be targeted to the remaining mature and old-growth forests found in the vicinity of these areas.

Climate velocity is an increasingly used metric to detect habitats, locations and regions which are exposed to high rates of climate change and displacement. In general, velocities are measured based on the assumption that future climatically similar locations can occur anywhere in the study landscape. However, this assumption can provide a biased basis for habitats which are constrained to specific environmental conditions. For such habitats, a set of selected suitable locations may provide ecologically more realistic velocity measures. Here, we focus on one environmentally constrained habitat, aapa mires, which are peat-accumulating EU Habitats Directive priority habitats, whose ecological conditions and biodiversity values may be jeopardised by climate change. We assess the climate exposure of aapa mires in Finland by developing velocity metrics separately for the whole ≥10 ha aapa mire complexes (‘aapa mires’) and their wettest flark-dominated parts (‘flark fens’). Velocity metrics were developed for six bioclimatic variables (growing degree days (GDD5), mean January and July temperatures, annual precipitation, and May and July water balance, based on climate data for 1981–2010 and for 2040–2069 as derived from global climate models for two Representative Concentration Pathways (RCP4.5 and RCP8.5). For the six variables, velocities were calculated based on the distance between climatically similar present-day and nearest future mire, divided by the number of years between the two periods, and by excluding the unsuitable matrix. Both aapa mires and flark fens showed high exposure (>5 km/year) to changes in January temperature, and often also considerably high velocities for GDD5 and July temperatures. The flark fens showed significantly higher climate velocities than the aapa mires and had a smaller amount of corresponding habitat in their surroundings. Thus, many of the studied mires, particularly the flark fens, are likely to face increased risks of exposure due to changes in winter and summer temperatures. Moreover, considerable changes in precipitation-related conditions may occur at the southern margin of the aapa mire zone. Our results show that specifically tailored climate velocity metrics can provide a useful quantitative tool to inform conservation and management decisions to support the ecosystem sustainability of this EU Habitats Directive biotope and targeting restoration towards the most vulnerable aapa mires. Highlights • Aapa mires are EU Habitats Directive priority habitats of high conservation value • Velocity assessments enable quantifying the exposure of habitats to climate change • Boreal aapa mires will face notable exposure risks due to warming climate • Wet flark fens with open water pools and their biodiversity are particularly at risk • Climate velocity information supports adaptive biodiversity conservation planning

Success rates for conservation translocations of species are low and there is a need for increased understanding of how this activity is best applied. Here, using static species distribution models and a spatially-explicit dynamic simulation model, RangeShifter, we examine the impacts of habitat cover in recipient landscapes, allocation of individuals into multiple sites and species trait characteristics on the long-term fate of hypothetical translocations of a grassland specialist butterfly, Maniola jurtina, in Finland. While persistence of populations introduced to climatically suitable locations northwards of the current range can be increased by selecting sites with increasing habitat cover and by allocation of individuals to multiple release sites, local population growth rate is shown to be the key parameter in determining likely translocation success. We conclude that the long-term persistence of translocated habitat specialist butterflies, particularly with low growth rates, appears to be uncertain in modern-day fragmented grassland networks and that translocation activities should prioritize management that improves local growth rate.

Translocations have been advocated as a conservation tool helping species adapt to climate and land-use change, but well-documented examples of invertebrates’ translocations are rare. The paper describes a successful translocation of the threatened Clouded Apollo butterfly ( Parnassius mnemosyne ) in Finland, compares this to a specific failed translocation, and presents conclusions for conservation planning as to factors contributing to the success. Two apparent key characteristics of the successful translocation were greater abundance of larval resources and less open landscape. The successful site was surrounded by forest, which strongly restricted emigration, crucially supporting the survival of the small initial population. Based on 20 mated females’ translocation in 2000, the local population increased slowly, reaching 600 butterflies in 2011. A large translocation patch together with host-plant abundance enabled successful establishment of the local population. Availability of other suitable grassland patches sufficiently nearby was an additional key characteristic, facilitating the Clouded Apollo’s expansion. However, the expansion rate was low; it took seven years for the butterflies to colonise the five nearest patches, only 10–200 m from the translocation patch. By 2013, they had colonised all suitable semi-natural grassland patches within 2 km from the translocation site and established a seemingly viable metapopulation with 11 subpopulations. The results point to the significance of local habitat area and landscape quality, along with conditions restricting emigration, in determination of suitable translocation sites.

Studies on the determinants of plant-herbivore and herbivore-parasitoid associations provide important insights into the origin and maintenance of global and local species richness. If parasitoids are specialists on herbivore niches rather than on herbivore taxa, then alternating escape of herbivores into novel niches and delayed resource tracking by parasitoids could fuel diversification at both trophic levels. We used DNA barcoding to identify parasitoids that attack larvae of seven Pontania sawfly species that induce leaf galls on eight willow species growing in subarctic and arctic-alpine habitats in three geographic locations in northern Fennoscandia, and then applied distance- and model-based multivariate analyses and phylogenetic regression methods to evaluate the hierarchical importance of location, phylogeny and different galler niche dimensions on parasitoid host use. We found statistically significant variation in parasitoid communities across geographic locations and willow host species, but the differences were mainly quantitative due to extensive sharing of enemies among gallers within habitat types. By contrast, the divide between habitats defined two qualitatively different network compartments, because many common parasitoids exhibited strong habitat preference. Galler and parasitoid phylogenies did not explain associations, because distantly related arctic-alpine gallers were attacked by a species-poor enemy community dominated by two parasitoid species that most likely have independently tracked the gallers' evolutionary shifts into the novel habitat. Our results indicate that barcode- and phylogeny-based analyses of food webs that span forested vs. tundra or grassland environments could improve our understanding of vertical diversification effects in complex plant-herbivore-parasitoid networks.

Aim: Understanding the relative contribution of different species interactions in shaping community assembly has been a pivotal aim in community ecology. Biotic interactions are acknowledged to be important at local scales, although their signal is assumed to weaken over longer distances. We examine the relationship between positive, neutral and negative pairwise bird abundance distributions and the phylogenetic and functional distance between these pairs after first controlling for habitat associations. Location: France and Finland. Time period: 1984 to 2011 (Finland), 2001 to 2012 (France). Major Taxa studied: Birds. Methods: We used results from French and Finnish land bird monitoring programmes, from which we created three independent datasets (French forests, French farmlands and Finnish forests). Separately for the three datasets, we fitted linear mixed-effects models for pairwise abundance values across years per point count station to infer the association between all common species pairs, while controlling for geographical distribution and habitat associations, and saved pairwise regression coefficients for further analyses. We used a null model approach to infer whether the observed associations (effect sizes) differ from random. Finally, using quantile regression, we analysed the relationships between functional dissimilarity/phylogenetic distance and effect sizes. Results: Our results show both negative and positive species interactions, although negative interactions were twice as common as positive interactions. Closely related species were more likely to show strong associations, both negative and positive, than more distant species across broad spatial scales. For functional dissimilarity, the results varied across datasets. Main conclusions: Our results emphasize the potential of functional and phylogenetic proximity in generating both negative and positive species associations, which can produce pervasive patterns from local to geographical scales. Future assembly studies should refrain from strict dichotomies, such as compensatory dynamics versus environmental forcing, and instead consider the possibility of positive interactions. peerReviewed