Importance of estimating matrix quality for modeling species distribution in complex tropical landscapes: a test with Atlantic forest small mammals

Information to guide decision making is especially urgent in human dominated landscapes in the tropics, where urban and agricultural frontiers are still expanding in an unplanned manner. Nevertheless, most studies that have investigated the influence of landscape structure on species distribution have not considered the heterogeneity of altered habitats of the matrix, which is usually high in human dominated landscapes. Using the distribution of small mammals in forest remnants and in the four main altered habitats in an Atlantic forest landscape, we investigated 1) how explanatory power of models describing species distribution in forest remnants varies between landscape structure variables that do or do not incorporate matrix quality and 2) the importance of spatial scale for analyzing the influence of landscape structure. We used standardized sampling in remnants and altered habitats to generate two indices of habitat quality, corresponding to the abundance and to the occurrence of small mammals. For each remnant, we calculated habitat quantity and connectivity in different spatial scales, considering or not the quality of surrounding habitats. The incorporation of matrix quality increased model explanatory power across all spatial scales for half the species that occurred in the matrix, but only when taking into account the distance between habitat patches (connectivity). These connectivity models were also less affected by spatial scale than habitat quantity models. The few consistent responses to the variation in spatial scales indicate that despite their small size, small mammals perceive landscape features at large spatial scales. Matrix quality index corresponding to species occurrence presented a better or similar performance compared to that of species abundance. Results indicate the importance of the matrix for the dynamics of fragmented landscapes and suggest that relatively simple indices can improve our understanding of species distribution, and could be applied in modeling, monitoring and managing complex tropical landscapes.     

Patterns and strategies of winter habitat selection in alpine capercaillie

Based on radio telemetry, habitat distribution of 32 individual capercaillie Tetrao urogallus was compared with habitat availability at various levels of scale At forest stand level, capercaillie preferred large patches of late succession stages, and selected for moderate canopy closure and high abundance of feeding trees Hens and cocks selected home ranges with high proportions of old forest, and range size was related to old forest fragmentation Winter survival was high independently of habitat selection In cocks, habitat use was affected by social spacing, home range size and use of old forest were age-dependent, and habitat composition of winter ranges indirectly related to survival and mating success in spring Topography influenced habitat selection, as the birds preferred gentle slopes At the landscape scale, the distribution of bilberry Vaccinium myrtillus was the key to capercaillie habitat use, indicating that habitat requirements in autumn and spring influenced selection of winter ranges The study confirms that capercaillie in central Europe select habitats according to structural features typical of the boreal forests of the species' main distribution range However, spatio-temporal variation in resource abundance at the landscape scale sets significant limits to suitability of alpine capercaillie habitats     

Wildlife habitat analysis – a multidimensional habitat management model

In intensively cultivated landscapes, the effects of land use – changing habitat quality and habitat availability - on wildlife populations are of major importance for wildlife management. Populations of some species reach high densities, grow rapidly, and can therefore cause damage to tree regeneration in forests; chamois (Rupicapra rupicapra) is an example. Other species, like capercaillie (Tetrao urogallus), suffer from substantial habitat loss resulting in a population decline. Consequently, the number of individuals and the quality of habitat are of crucial relevance for the development of wildlife management concepts. It is critical to know, which areas provide suitable habitat conditions for a species, and what quantity and quality of habitat is required to achieve a certain population size.

In order to evaluate habitat quality and to link wildlife research to practical habitat management, an integrated habitat management model has been designed. The model is based on a multi-dimensional habitat analysis which employs different methodological levels, which were defined according to different spatial scales. On a country scale (level 1), the wildlife ecological landscape type (WELT) is introduced. For this study the federal state of Baden-Wuerttemberg is divided into units which represent distinct regions with similar landscape ecological habitat conditions for wildlife species. On an eco-regional scale (level 2), the landscape ecological habitat potential (LEHP) was developed. It is based on the evaluation of species-related landscape parameters within an exemplary eco-region and provides information about the potential habitat available to a population. On two local scales (level 3: forest district, level 4: forest stand), a habitat structure analysis was conducted, which serves as a foundation for habitat improvement and the monitoring of habitat conditions. The three methodological elements WELT, LEHP and habitat structure analysis were integrated into a habitat management model. The model uses chamois and capercaillie as examples, but can be equally applied to other species and wildlife management regimes.     

Determinants of Plant Community Assembly in a Mosaic of Landscape Units in Central Amazonia: Ecological and Phylogenetic Perspectives

The Amazon harbours one of the richest ecosystems on Earth. Such diversity is likely to be promoted by plant specialization, associated with the occurrence of a mosaic of landscape units. Here, we integrate ecological and phylogenetic data at different spatial scales to assess the importance of habitat specialization in driving compositional and phylogenetic variation across the Amazonian forest. To do so, we evaluated patterns of floristic dissimilarity and phylogenetic turnover, habitat association and phylogenetic structure in three different landscape units occurring in terra firme (Hilly and Terrace) and flooded forests (Igapó). We established two 1-ha tree plots in each of these landscape units at the Caparú Biological Station, SW Colombia, and measured edaphic, topographic and light variables. At large spatial scales, terra firme forests exhibited higher levels of species diversity and phylodiversity than flooded forests. These two types of forests showed conspicuous differences in species and phylogenetic composition, suggesting that environmental sorting due to flood is important, and can go beyond the species level. At a local level, landscape units showed floristic divergence, driven both by geographical distance and by edaphic specialization. In terms of phylogenetic structure, Igapó forests showed phylogenetic clustering, whereas Hilly and Terrace forests showed phylogenetic evenness. Within plots, however, local communities did not show any particular trend. Overall, our findings suggest that flooded forests, characterized by stressful environments, impose limits to species occurrence, whereas terra firme forests, more environmentally heterogeneous, are likely to provide a wider range of ecological conditions and therefore to bear higher diversity. Thus, Amazonia should be considered as a mosaic of landscape units, where the strength of habitat association depends upon their environmental properties.     

Effects of landscape complexity and stand factors on arthropod communities in poplar forests

The arthropod communities are influenced by both local conditions and features of the surrounding landscape. Landscape complexity and stand factors may both influence arthropod communities in poplar forests, but the multiscale effects of these factors on poplar defoliators and natural enemies are still poorly understood. We collected poplar arthropods at 30 sampling sites within five forest landscapes in Xinjiang, China, and assessed whether landscape complexity and stand factors influence species abundance and diversity of poplar arthropods. Landscape complexity was quantified by several independent metrics of landscape composition, configuration, and connectivity at three spatial scales. We also determined the most powerful explanatory variables and the scale effect of each arthropod. Results found that landscape complexity and stand factors had different effects on different poplar arthropod communities. Landscape complexity promoted natural enemies at different spatial scales, but it inhibited the population of poplar defoliators at the scale of 200 m. Specifically, the abundance and diversity of all defoliators decreased with increasing proportion of nonhost plants. Landscape diversity only had a negative effect on defoliator abundance. The shape complexity of habitat patches increased the abundance of carabid beetles but reduced the abundance of green leafhoppers and migratory locusts. The abundance and diversity of predators increased with increasing structural connectivity of forest landscape. Additionally, both the abundance and diversity of all defoliators were positively correlated with the average height of herbaceous plants. Diversity of all defoliators increased with increasing size of host trees. The distance from sampling site to the nearest village positively influenced the abundance and diversity of all predators. Arthropod abundance and diversity in poplar forests were driven by stand factors and landscape complexity. Therefore, maintaining complex shape and structural connectivity of habitat patches and keeping poplar stands away from the village are crucial for management of forest landscape to enhance natural enemies. And in order to reduce the abundance of defoliators in poplar forest, the diversity of surrounding habitat types should be promoted within 200 m radii.     

Multi-scale turtle dove nest habitat selection in a Mediterranean agroforestry landscape: implications for the conservation of a vulnerable species

Determination of factors affecting nest habitat selection is a major topic in avian ecology, with strong implications for conservation purposes especially for the species with unfavorable status. The turtle dove (Streptopelia turtur) is a vulnerable species that has undergone a rapid and serious decline across its distribution range. I investigated the effect of different variables at two spatial scales (10-m radius, nest site; and 100-m radius, landscape) on the probability of presence of turtle dove nests in an agroforestry system of Central Morocco. Topography, habitat structure, human disturbance, and land use parameters were measured at nests (n?=?70) and random points (n?=?70) at both scales. Generalized linear model analyses showed that, at the nest site scale, tree height best explained occurrence of turtle dove nests (with nest occurring preferentially in smaller trees). At the landscape scale, nest occurrence probability decreased with elevation and distance to the nearest forest edge, and increased with forest cover and distance to the nearest habitation. Comparison of explanatory power of the single-scale models showed that the most relevant scale was the nest site level, followed by landscape scales, but the model including both nest-scale and landscape-scale variables was best. The variation partitioning analysis confirmed this pattern. In study area, the turtle dove nest habitat selection process occurs within a relatively small scale, but the joint effect of variables at the two scales is relevant. From a practical perspective, it would be interesting to reproduce the same experimental approach on other Mediterranean breeding habitats (agricultural and other forest habitats) to find out if this species would adopt the same nest habitat selection pattern.     

Habitat selection by capercaillie in summer and autumn: Is bilberry important?

The use of habitat by female and male adult capercaillie Tetrao urogallus during summer and autumn was studied by comparing the distribution of radio locations of birds with the availability of habitat at forest stand, home range and landscape level in an area of the Bavarian Alps, Germany. Capercaillie preferred forests with structural features typical of their main distribution range, the boreal forest: they selected large patches of old forest with moderate canopy cover of about 50%, and a well developed field layer with high proportions of bilberry Vaccinium myrtillus. Hens selected both home ranges and sites within home ranges in old forest. Ranges selected by cocks did not differ from availability in the study area, but they preferred old forest within their ranges. The size of home ranges was negatively related to bilberry cover both in hens and cocks. The distribution of bilberry also determined habitat use by capercaillie at the landscape scale. The study demonstrated that bilberry is the major determinant of the selection of habitat by capercaillie in landscapes with sparse and fragmentary cover of ericaceous shrubs, such as central Europe.     

Balancing the needs of capercaillie (Tetrao urogallus) and moose (Alces alces) in large-scale human land use

The capercaillie has been negatively affected by the loss of mature forests. However, forestry creates young plantations offering a superabundant food supply for moose. Using two spatial scales, we tested whether the landscape-level environmental requirements of the capercaillie and moose differ. We compared the spatial association between the abundances of the two species in 50-?×?50-km grids and, using a set of regression models, analyzed how it was affected by various land use variables in five regions of Finland. Both species were generally most abundant in the same grid cells. Moreover, the association between abundance and several landscape variables was very similar for both species. Forest cover had a positive impact on both species in Eastern and South-Western Finland. Only in Western Finland was the capercaillie more positively associated with older forest than the moose. Human impact variables were negatively related to both capercaillie and moose abundance in Eastern and South-Western Finland, the effect being stronger for capercaillie. In Northern Finland, human impact turned positive. Our results highlight that, on broad landscape and regional scales, we might not need to make trade-offs in management decisions concerning capercaillie and moose. While considering regional land use planning, the primary goal for both species seems to be to secure large areas of forest, preferably at a distance from human settlement.     

<Emphasis Type="Italic">PRUNUS</Emphasis>: a spatially explicit demographic model to study plant invasions in stochastic,heterogeneous environments

To model the invasion of Prunus serotina invasion within a real forest landscape we built a spatially explicit, non-linear Markov chain which incorporated a stage-structured population matrix and dispersal functions. Sensitivity analyses were subsequently conducted to identify key processes controlling the spatial spread of the invader, testing the hypothesis that the landscape invasion patterns are driven in the most part by disturbance patterns, local demographical processes controlling propagule pressure, habitat suitability, and long-distance dispersal. When offspring emigration was considered as a density-dependent phenomenon, local demographic factors generated invasion patterns at larger spatial scales through three factors: adult longevity; adult fecundity; and the intensity of self-thinning during stand development. Three other factors acted at the landscape scale: habitat quality, which determined the proportion of the landscape mosaic which was potentially invasible; disturbances, which determined when suitable habitats became temporarily invasible; and the existence of long distance dispersal events, which determined how far from the existing source populations new founder populations could be created. As a flexible “all-in-one” model, PRUNUS offers perspectives for generalization to other plant invasions, and the study of interactions between key processes at multiple spatial scales.     

Probabilistic modeling and mapping of plant indicator species in a Northeast Oregon industrial forest,USA

Managing forest ecosystems for sustainable, multiple use requires forest resource managers to understand and predict how plant species composition and distribution varies across environmental gradients and responds to landscape scale disturbances. This study demonstrates predictive vegetation modeling and mapping for a Northeast Oregon forest using non-parametric Multiplicative Regression (NPMR) with presence/absence data for the species Clintonia uniflora (CLUN) and a set of stand structural and raster-based predictor variables. NPMR is a flexible probability modeling system that can find the best subset of habitat factors influencing species occurrence. NPMR was compared with logistic regression (LR) by building reduced models from variables selected as best by NPMR and full models from variables identified as significant with a forward stepwise process and further manual testing. log β was used to select models with the highest predictive capability. NPMR models were less complex and had higher predictive capability than LR for all modeling approaches. Spatial coordinates were among the most powerful predictors and the modeling approach with physiographic and stand structural variables together was the most improved relative to the average frequency of occurrence. GIS probability maps produced with the application of the physiographic models showed good spatial congruence between high probability values and plots that contained CLUN. NPMR proved to be a reliable probability modeling and mapping tool that could be used as the analytical link between monitoring and quantifying the status and trends of vegetation resources.     

Beetle diversity in a matrix of old-growth boreal forest: influence of habitat heterogeneity at multiple scales

The relative contribution of compositional and structural heterogeneity on biodiversity is currently ambiguous because field studies generally integrate these two sources of habitat heterogeneity into a single index. We established the relationship between species richness of ground-dwelling and flying beetles and compositional and structural attributes of forest heterogeneity. The relationship was evaluated at two spatial scales: the scale of forest stand, corresponding to an 11.3  m radius, and the scale of landscape, corresponding to either a 400 or 800  m radius. Seventy stands were sampled in the matrix of old-growth boreal forest of the North Shore region of Québec, Canada, during the summers of 2004 and 2005. A total of 133 ground-dwelling beetle species (range: 4–42 species per site) were captured in the pitfall traps and 251 flying species (range 16–58 species per site) in flight-interception traps. We found that the most relevant type of heterogeneity to explain variations in species richness and the significance of landscape scale information varied between groups of beetles. Compositional heterogeneity (i.e. the number of species of forest trees and shrubs) at the stand scale best predicted species richness in ground-dwelling beetles. On the other hand, it was the combined influence of structural and compositional habitat heterogeneity at stand and landscape scales that best explained richness patterns in flying beetles. Our study outlines the significance of considering multiple types and spatial scales of habitat heterogeneity when describing patterns of species richness.     

Capturing cross-scalar variation of habitat selection with grid sampling: an example with hazel grouse (Tetrastes bonasia L.)

The objective of this study was to investigate a grid-based sampling design to determine the cross-scalar selection of habitat by a territorial animal species: the hazel grouse (Tetrastes bonasia L.). In each of three sites with increasing hazel grouse nest site density, three lattice grids were used to measure both the habitat variables and the species occurrence in 100 30?×?30 m cells. We calculated the average values for habitat variables, as well as use versus non-use by the species, at three spatial scales: small (1?×?1 cell), intermediate (2?×?2 cells) and large (3?×?3 cells). Generalised linear mixed models were integrated into a method of variation and hierarchical partitioning and used to assess the relationship between the habitat variables and the species preferences at each scale. In all scales, species selection was associated with ground layer composition. Selection was also associated with the composition of the woody layer and negatively associated with dominance of tor grass (Brachypodium rupestre (Host) Roem. & Schult.) at the two larger scales. Both litter cover and thinning contributed positively to the habitat selection at the two smaller scales. The other variables were significant only at one scale or explained a relatively low proportion of the variation at multiple scales. Neither the management nor the stand structure variables played a significant independent role across scales when compared with ground layer variables. The total variation explained was highest (ca. 90 %) at the large scale. This finding indicates the possibility of obtaining cross-scalar hazel grouse preferences from grid-based sampling, provided that spatial autocorrelation in the data is handled appropriately.     

Occupancy Models of Nesting-Season Habitat Associations of Red-Shouldered Hawks in Central Minnesota

ABSTRACT Red-shouldered hawks (Buteo lineatus) are a species of special conservation concern in much of the Great Lakes region, and apparent population declines are thought to be primarily due to habitat loss and alteration. To evaluate red-shouldered hawk-habitat associations during the nesting season and at the landscape scale, we conducted repeated call-broadcast surveys in central Minnesota, USA, across 3 landscapes that represented a range of landscape conditions as a result of differing management practices. In 2004, we conducted repeated call-broadcast surveys at 131 locations in 2 study areas, and in 2005, we surveyed 238 locations in 3 study areas. We developed models relating habitat characteristics at 2 spatial scales to red-shouldered hawk occupancy and assessed support for these models in an information-theoretic framework. Overall, a small proportion of nonforest (grass, clear-cut area, forest <5 yr old), and a large proportion of mature deciduous forest (>40 yr old), had the strongest association with red-shouldered hawk occupancy (proportion of sites occupied) at both spatial scales. The landscape conditions we examined appeared to contain a habitat transition important to red-shouldered hawks. We found, in predominately forest landscapes, the amount of open habitat was most strongly associated with red-shouldered hawk occupancy, but in landscapes that included slightly less mature forest and more extensive open habitats, the extent of mature deciduous forest was most strongly associated with red-shouldered hawk occupancy. Our results suggested that relatively small (<5 ha) patches of open habitat (clear-cuts) in otherwise forested landscapes did not appear to influence red-shouldered hawk occupancy. Whereas, in an otherwise similar landscape, with smaller amounts of mature deciduous forest and larger (>15 ha) patches of open habitat, red-shouldered hawk occupancy decreased, suggesting a threshold in landscape composition, based on both the amount of mature forest and open area, is important in managing forest landscapes for red-shouldered hawks. Our results show that during the nesting season, red-shouldered hawks in central Minnesota occupy at similar rates landscapes with different habitat compositions resulting from different management strategies and that management strategies that create small openings may not negatively affect red-shouldered hawk occupancy.     

Biome transitions as centres of diversity: habitat heterogeneity and diversity patterns of West African bat assemblages across spatial scales

It is widely accepted that species diversity is contingent upon the spatial scale used to analyze patterns and processes. Recent studies using coarse sampling grains over large extents have contributed much to our understanding of factors driving global diversity patterns. This advance is largely unmatched on the level of local to landscape scales despite being critical for our understanding of functional relationships across spatial scales. In our study on West African bat assemblages we employed a spatially explicit and nested design covering local to regional scales. Specifically, we analyzed diversity patterns in two contrasting, largely undisturbed landscapes, comprising a rainforest area and a forest‐savanna mosaic in Ivory Coast, West Africa. We employed additive partitioning, rarefaction, and species richness estimation to show that bat diversity increased significantly with habitat heterogeneity on the landscape scale through the effects of beta diversity. Within the extent of our study areas, habitat type rather than geographic distance explained assemblage composition across spatial scales. Null models showed structure of functional groups to be partly filtered on local scales through the effects of vegetation density while on the landscape scale both assemblages represented random draws from regional species pools. We present a mixture model that combines the effects of habitat heterogeneity and complexity on species richness along a biome transect, predicting a unimodal rather than a monotonic relationship with environmental variables related to water. The bat assemblages of our study by far exceed previous figures of species richness in Africa, and refute the notion of low species richness of Afrotropical bat assemblages, which appears to be based largely on sampling biases. Biome transitions should receive increased attention in conservation strategies aiming at the maintenance of ecological and evolutionary processes.     

Habitat partitioning in endangered Cantabrian capercaillie Tetrao urogallus cantabricus

The endangered Cantabrian capercaillie (Tetrao urogallus cantabricus) lives at the southern edge of tetraonids’ distribution range, in entirely deciduous forests. Its conservation planning has been always lek-centred. There is very little information about the specific habitat requirements of hens and broods, even though reproductive success appears to be a limiting factor. We analysed summer surveys from 1997 to 2004, carried out to estimate the reproductive success of the population. We compared the habitat characteristics at different spatial scales of hens with broods, broodless hens, and cocks in summer, with the better known spring habitat in display areas. Summer habitat showed higher proportion of open areas and was associated with more rugged zones at moderate spatial scales (78 ha) than spring habitat at display areas. Cocks and hens showed summer habitat partitioning; hens were associated with higher proportions of open and shrubby habitats. Furthermore, broodless hens preferred areas with higher slope variability than the display and summer areas preferred by cocks. These differences may reflect the sexual dimorphism of the species in reproductive role, energetic demands and conspicuousness. At larger spatial scales a previously developed habitat suitability model performed well to predict good brood-rearing areas. Hens with broods were located in the best-preserved areas in the range, mainly characterized by higher proportion of forest cover at a large (50 km²) scale. We suggest that these characteristics indicate refuge habitats where Cantabrian capercaillie can still breed successfully.     

Spatially explicit conservation issues for threatened bird species in Mediterranean farmland landscapes

Coupling habitat models based on GIS and on ground variables could help identify suitable areas (by means of landscape models obtained by GIS variables) to concentrate management actions for species’ conservation. In this study, the habitat requirements of Lesser Greys (LGS) and Woodchat Shrikes (WS), two threatened farmland bird species declining in Europe, were assessed in Apulia (south-eastern Italy) by means of binary logistic regression at two different levels: landscape (using GIS-measured variables); and, territory (using ground-measured variables) scales. The LGS occurrence at landscape scale was correlated to steppe-like areas and cereal crops. At the territory level, significant effects were detected for deciduous forests and the presence of isolated trees and shrubs. The WS occurrence at landscape scale was promoted by steppe-like areas and cereal crops, whereas, at the territory level significant effects were detected for steppe-like areas positively and suburban areas negatively. The landscape model was extrapolated to the entire region. Within highly suitable areas (occurrence probability higher than 0.66 according to the landscape model), we measured average habitat features and compared them with the optimal mosaic depicted by the territory level models. This allowed us to give spatially explicit and site-specific management recommendations for these two threatened species. LGS will mostly benefit from an increase in isolated shrubs and trees; whereas for WS, the most widespread recommendations are to increase steppe-like habitat and to prevent further urbanisation.Coupling “coarse” landscape models with the species ecology provided by fine-scaled models can integrate relevant information on species potential distribution and territory level requirements, making planning fine-tuned habitat management (within potentially suitable landscapes) in a spatially explicit way possible.     

Multiscale assessment of the influence of habitat structure and composition on bird assemblages in boreal forest

The relative contributions of habitat structure and composition to biodiversity are often scale-dependent. Although bird communities in boreal forest have been largely altered and threatened by forest harvesting, bird habitat selection in this ecosystem has not been fully understood. Our study aimed to assess the relative contributions of habitat structure and composition on the assemblages of boreal birds at multiple spatial scales characterized by radii ranging from 100 to 1,000?m. We recorded bird species occurrence at 96 stations located in an old-growth forest in the C?te-Nord region of Québec, Canada. We characterized habitat structure using the proportion of dense, open, and sparse stands, and habitat composition using the proportions of coniferous, mixedwood, and deciduous stands. We used partial canonical correspondence analyses and hierarchical variance partitioning to assess the relative contribution of habitat structure and composition on bird assemblage, and logistic regression to model the probability of occurrence for individual species in response to habitat variables. Our results revealed that habitat structure and composition explained similar proportions of the variance in bird assemblage (21.7 vs. 21.6?%), regardless of spatial scale. Whilst logistic regression yielded fair predictions in the occurrence of individual species (i.e., area under the receiver-operating characteristic curve >0.70 for 90?% of the species), it further confirmed our findings in community level analysis. Our study indicates that habitat structure and composition are both important in shaping bird assemblages, but spatial scale draws little influence on their relative contributions.     

Multi-scale habitat selection in highly territorial bird species: Exploring the contribution of nest,territory and landscape levels to site choice in breeding rallids (Aves: Rallidae)

Habitat selection often involves choices made at different spatial scales, but the underlying mechanisms are still poorly understood, and studies that investigate the relative importance of individual scales are rare. We investigated the effect of three spatial scales (landscape, territory, nest-site) on the occurrence pattern of little crake Zapornia parva and water rail Rallus aquaticus at 74 ponds in the Masurian Lakeland, Poland. Habitat structure, food abundance and water chemical parameters were measured at nests and random points within landscape plots (from 300-m to 50-m radius), territory (14-m) and nest-site plots (3-m). Regression analyses suggested that the most relevant scale was territory level, followed by landscape, and finally by nest-site for both species. Variation partitioning confirmed this pattern for water rail, but also highlighted the importance of nest-site (the level explaining the highest share of unique variation) for little crake. The most important variables determining the occurrence of both species were water body fragmentation (landscape), vegetation density (territory) and water depth (at territory level for little crake, and at nest-site level for water rail). Finally, for both species multi-scale models including factors from different levels were more parsimonious than single-scale ones, i.e. habitat selection was likely a multi-scale process. The importance of particular spatial scales seemed more related to life-history traits than to the extent of the scales considered. In the case of our study species, the territory level was highly important likely because both rallids have to obtain all the resources they need (nest site, food and mates) in relatively small areas, the multi-purpose territories they defend.     

Multilevel landscape utilization of the Siberian flying squirrel: Scale effects on species habitat use

Animals use and select habitat at multiple hierarchical levels and at different spatial scales within each level. Still, there is little knowledge on the scale effects at different spatial levels of species occupancy patterns. The objective of this study was to examine nonlinear effects and optimal‐scale landscape characteristics that affect occupancy of the Siberian flying squirrel, Pteromys volans, in South‐ and Mid‐Finland. We used presence–absence data (n = 10,032 plots of 9 ha) and novel approach to separate the effects on site‐, landscape‐, and regional‐level occupancy patterns. Our main results were: landscape variables predicted the placement of population patches at least twice as well as they predicted the occupancy of particular sites; the clear optimal value of preferred habitat cover for species landscape‐level abundance is a surprisingly low value (10% within a 4 km buffer); landscape metrics exert different effects on species occupancy and abundance in high versus low population density regions of our study area. We conclude that knowledge of regional variation in landscape utilization will be essential for successful conservation of the species. The results also support the view that large‐scale landscape variables have high predictive power in explaining species abundance. Our study demonstrates the complex response of species occurrence at different levels of population configuration on landscape structure. The study also highlights the need for data in large spatial scale to increase the precision of biodiversity mapping and prediction of future trends.     

Topographic and forest-stand variables determining epiphytic lichen diversity in the primeval beech forest in the Ukrainian Carpathians

The Uholka-Shyrokyi Luh area of the Carpathian Biosphere Reserve is considered the largest and the most valuable primeval beech forest in Europe for biodiversity conservation. To study the impact of different topographic and forest-stand variables on epiphytic lichen diversity a total of 294 systematically distributed sampling plots were surveyed and 198 epiphytic lichen species recorded in this forest landscape, which has an uneven-aged structure. The obtained data were analysed using a non-metric multidimensional ordination and a generalized linear model. The epiphytic lichen species density at the plot level was mainly influenced by altitude and forest-stand variables. These variables are related to both the light availability i.e. canopy closure, and the habitat diversity, i.e. the developmental stage of the forest stands and the mean stem diameter. We found that lichen species density on plots with a relatively open canopy was significantly higher than on plots with a fairly loose or closed canopy structure. The late developmental stage of forest stands, which is characterized by a large number of old trees with rough and creviced bark, had a strong positive effect on lichen species density. In the Uholka-Shyrokyi Luh primeval forest the mean stem diameter of beech trees significantly correlated with lichen species density per plot. Similar trends in the species diversity of nationally red-listed lichens were revealed. Epiphytic lichens with a high conservation value nationally and internationally were found to be rather abundant in the Uholka-Shyrokyi Luh area, which shows its international importance for the conservation of forest-bound lichens.