Small Habitat Patches Research Articles

Local habitat features explain the distribution of the imperiled grass pickerel (Esox americanus vermiculatus)

We investigated patterns of grass pickerel (Esox americanus vermiculatus Lesueur, 1846) distribution in three watersheds in Ontario, Canada, using site- and reach-scale habitat variables and fish community assemblage data to determine why this species occurs sporadically throughout watersheds despite abundant seemingly suitable, but unoccupied, habitat. Habitat and fish community data were collected using conventional field sampling methods, and reach-scale habitat data were compiled with the aid of a geographic information system. We found that occupied sites had lower baseflow indices and reach slopes but higher conductivity and agricultural land uses than unoccupied sites. More grass pickerel were detected when conductivity, channel cover, and wetlands in the floodplain were highest and bank slopes lowest; this is consistent with habitat preferences described elsewhere in its range. Habitat features at the site scale appeared more important than reach-scale features suggesting that grass pickerel may be using small habitat patches. This study identifies habitat elements important to grass pickerel and offers insights into management implications.

Riparian and Upland Afforestation: Improving Success by Excluding Deer from Small Areas with Low Fencing

We propose that small patches of land protected by low (1.2-m tall) fence is a viable approach for restoring and/or conserving forests in riparian or upland areas with high white-tailed deer (Odocoileus virginianus Zimmerman) populations. We also propose that this new approach may be advantageous because, unlike tree shelters, fenced areas protect shrubs just as well as trees in afforestation projects. Multi-year field experiments were performed involving deer exclosures where fence height and fenced area were manipulated in upland and lowland pasture and forest settings. Results show that low fencing significantly increased seedling survival and growth relative to unfenced areas when fenced areas were small (i.e., less than or equal to ∼100 m2). Moreover, tall fencing (1.8 or 2.3 m) did not provide significantly greater protection than shorter (1.2-m) fencing when the fenced areas were kept small. We propose that creating small patches of deer-free pasture or forest habitat will greatly support new approaches to afforestation such as applied nucleation. Finally, we show that low-stature fencing may also have application for protecting larger areas (≥0.8 ha) if the fencing is deployed around the perimeter as two low fences erected in parallel and with a small (3-m) space between them. We conclude that low fencing can result in levels of survival and growth of both trees and shrubs suitable to meet the success criteria for afforestation projects funded by the US federal government.

GIS-based habitat mapping and population estimation for the Gulf Coast kangaroo rat (Dipodomys compactus) in the Carrizo Sands Region of Texas, USA

The Gulf Coast kangaroo rat, Dipodomys compactus, is one of five kangaroo rat species occurring in Texas (USA) and probably the least studied. This endemic species has specific habitat requirements, primarily deep loose sand and minimal canopy cover from woody vegetation. On the northern edge of its geographic range, populations of the species are limited to the Carrizo Sands Region and are likely isolated from larger populations farther south. Using a geographic information system (GIS)-based map of suitable habitat coupled with roadside surveys, we determined that habitat of D. compactus is highly fragmented within the Carrizo Sands. Depending on assumed density of individuals we estimated a region-wide population between 50,000 and 240,000 individuals although 50% of this population is expected to be distributed among 11 large (≥500 ha) habitat patches. The remainder of the population may be scattered among much smaller habitat patches. In this regard, the overall spatial population structure of D. compactus may be similar to some of the highly endemic Dipodomys species in California (USA). If subpopulations of D. compactus are functionally isolated from one another (due to limited dispersal of individuals) then long-term persistence of the species in the Carrizo Sands region over the next few decades may be in jeopardy. Therefore, distribution and abundance of D. compactus in the Carrizo Sands may need to be routinely monitored particularly if future genetic studies reveal this northernmost population to be genetically unique.

The effect of landscape structure on dispersal distances of the Eurasian red squirrel.

Landscape structure can affect dispersal and gene flow in a species. In urban areas, buildings, roads, and small habitat patches make the landscape highly fragmented and can inhibit movement and affect dispersal behavior. Similarly, in rural forested areas, large open areas, such as fields, may act as barriers to movement. We studied how landscape structure affects natal dispersal distances of Eurasian red squirrels (Sciurus vulgaris) in an urban area and a rural area in Finland, by monitoring juvenile red squirrels with radio telemetry. We observed extremely long dispersal distances—up to 16 km—in the rural study area, but shorter distances—on average only half a kilometer—in the urban study area. The landscape structure affected the eventual dispersal paths; in the rural landscape, dispersers favored spruce dominated areas and avoided fields along their dispersal route, although they occasionally even crossed wide fields. In the urban landscape, squirrels preferred areas with deciduous or coniferous trees. The movement steps made by dispersers were longer in the more hostile landscape compared to forested areas. Despite these effects on movement path, the landscape structure only had a minor effect on straight line dispersal distances moved from the natal nest. In other words, individuals moved longer distances and were likely to circumvent barriers in their path, but this did not affect how far they settled from their natal home. This result indicates that, although landscape structure has obvious effects on movement, it still may have only a small effect on other aspects of the population, for example, gene flow.

Attenuated post-fire fauna succession: the effects of surrounding landscape context on post-fire colonisation of fauna

Context After fire, immigration from outside burnt areas is important for the recovery of faunal communities. However, for recovery to occur, the matrix around the fire must support source populations of immigrants. Therefore, the landscape context of fires may be a critical determinant of the species pool available for (re)colonisation, hence post-fire community composition. Increasingly, fires occur in fragmented systems, and there is limited knowledge of how the surrounding landscape interacts with post-fire community recovery. Aim The present study aimed to examine how landscape context influences faunal communities after large wildfires. Methods Three reserves burnt by wildfire were examined ~18 months before the study in the Mallee region of south-eastern Australia. In all cases the burnt area consisted of natural mallee woodland. Two fires occurred within a matrix of extensive natural vegetation, while the third fire burnt >80% of a reserve situated within a highly fragmented, largely agricultural landscape. Birds, reptiles and mammals were surveyed at 90 sites inside and outside the fire boundaries, and relationships of species occurrence to reserve location, burnt versus unburnt status and distance from fire edge were all examined. Key results Post-fire faunal communities reflected the species in the surrounding unburnt landscape. Notably, open habitat specialists, invasive species and species that can persist in small habitat patches were prominent within the fragmented system. Post-fire fauna communities were also influenced by variation of the natural vegetation surrounding the fire. The occurrence of species with low dispersal ability (i.e. reptiles) was influenced by local (patch scale) vegetation structure. 2Conclusions The landscape context of fires is a major driver of the composition of post-fire faunal communities. Our results highlight the potential loss of species sensitive to fragmentation from fire-prone natural vegetation within modified landscapes, and that a reduced pool of potential immigrants leads to ‘attenuated succession’, compromising recovery of the pre-fire community. Implications Post-fire colonists reflect the surrounding landscapes species pool, such that reserves surrounded by fragmented or otherwise low quality habitat are at risk of attenuated succession after fire. Landscape context should be incorporated into conservation planning in fire-prone ecosystems, including consideration of surrounding habitat quality and connectivity and protecting long unburnt vegetation.

Is habitat fragmentation bad for biodiversity?

In a review of landscape-scale empirical studies, Fahrig (2017a) found that ecological responses to habitat fragmentation per se (fragmentation independent of habitat amount) were usually non-significant (>70% of responses) and that 76% of significant relationships were positive, with species abundance, occurrence, richness, and other response variables increasing with habitat fragmentation per se. Fahrig concluded that to date there is no empirical evidence supporting the widespread assumption that a group of small habitat patches generally has lower ecological value than large patches of the same total area. Fletcher et al. (2018) dispute this conclusion, arguing that the literature to date indicates generally negative ecological effects of habitat fragmentation per se. They base their argument largely on extrapolation from patch-scale patterns and mechanisms (effects of patch size and isolation, and edge effects) to landscape-scale effects of habitat fragmentation. We argue that such extrapolation is unreliable because: (1) it ignores other mechanisms, especially those acting at landscape scales (e.g., increased habitat diversity, spreading of risk, landscape complementation) that can counteract effects of the documented patch-scale mechanisms; and (2) extrapolation of a small-scale mechanism to a large-scale pattern is not evidence of that pattern but, rather a prediction that must be tested at the larger scale. Such tests were the subject of Fahrig's review. We find no support for Fletcher et al.'s claim that biases in Fahrig's review would alter its conclusions. We encourage further landscape-scale empirical studies of effects of habitat fragmentation per se, and research aimed at uncovering the mechanisms that underlie positive fragmentation effects.

Global synthesis of conservation studies reveals the importance of small habitat patches for biodiversity

Island biogeography theory posits that species richness increases with island size and decreases with isolation. This logic underpins much conservation policy and regulation, with preference given to conserving large, highly connected areas, and relative ambivalence shown toward protecting small, isolated habitat patches. We undertook a global synthesis of the relationship between the conservation value of habitat patches and their size and isolation, based on 31 systematic conservation planning studies across four continents. We found that small, isolated patches are inordinately important for biodiversity conservation. Our results provide a powerful argument for redressing the neglect of small, isolated habitat patches, for urgently prioritizing their restoration, and for avoiding simplistic application of island biogeography theory in conservation decisions.

Population Genomic Analysis of North American Eastern Wolves (Canis lycaon) Supports Their Conservation Priority Status.

The threatened eastern wolf is found predominantly in protected areas of central Ontario and has an evolutionary history obscured by interbreeding with coyotes and gray wolves, which challenges its conservation status and subsequent management. Here, we used a population genomics approach to uncover spatial patterns of variation in 281 canids in central Ontario and the Great Lakes region. This represents the first genome-wide single nucleotide polymorphism (SNP) dataset with substantial sample sizes of representative populations. Although they comprise their own genetic cluster, we found evidence of eastern wolf dispersal outside of the boundaries of protected areas, in that the frequency of eastern wolf genetic variation decreases with increasing distance from provincial parks. We detected eastern wolf alleles in admixed coyotes along the northeastern regions of Lake Huron and Lake Ontario. Our analyses confirm the unique genomic composition of eastern wolves, which are mostly restricted to small fragmented patches of protected habitat in central Ontario. We hope this work will encourage an innovative discussion regarding a plan for managed introgression, which could conserve eastern wolf genetic material in any genome regardless of their potential mosaic ancestry composition and the habitats that promote them.

Loss of only the smallest patches will reduce species diversity in most discrete habitat networks.

Under many global-change scenarios, small habitat patches are the most vulnerable to destruction. For example, smaller ponds are at greater risk in a drying climate and their loss would remove any obligate aquatic individuals present. We asked what proportional loss of species diversity from metacommunities comprised of discrete habitat patches should be expected from attrition (complete loss) of only the smallest patches under such a premise. We analyzed 175 published datasets for different taxonomic groups (vertebrates, invertebrates, and plants) and habitat types (islands, habitat islands, and fragments). We simulated the destruction of only the smallest patches to an approximate 20% of total area (range: 15.2%-24.2%) and analyzed species loss. Mean [±95% CI] species loss was 12.7% [10.8, 14.6], although 18.3% of datasets lost no species. Four broad patterns of species loss were evident, reflecting underlying differences in minimum area requirements and the degree of species turnover among patches. Regression modeling showed species loss increased with greater species turnover among patches (βSIM ) and decreased with greater area scaling of diversity (i.e., larger power-law island species-area relationship exponents). Losses also increased with greater numbers of single-patch endemics and with increasing proportions of patches destroyed. After accounting for these predictors, neither taxonomic group nor habitat type increased explained variation in species loss. Attrition of the smallest patches removed species in >80% of metacommunities, despite all larger patches and >75% of total area remaining intact. At both 10% and 20% area reduction, median species loss across all datasets was around 50% higher than predicted from methods based on the species-area relationship. We conclude that any mechanism of global change that selectively destroys small habitat patches will lead to imminent extinctions in most discrete metacommunities.

Habitat Fragmentation Reduces Genetic Diversity and Connectivity of the Mexican Spotted Owl: A Simulation Study Using Empirical Resistance Models.

We evaluated how differences between two empirical resistance models for the same geographic area affected predictions of gene flow processes and genetic diversity for the Mexican spotted owl (Strix occidentalis lucida). The two resistance models represented the landscape under low- and high-fragmentation parameters. Under low fragmentation, the landscape had larger but highly concentrated habitat patches, whereas under high fragmentation, the landscape had smaller habitat patches that scattered across a broader area. Overall habitat amount differed little between resistance models. We tested eight scenarios reflecting a factorial design of three factors: resistance model (low vs. high fragmentation), isolation hypothesis (isolation-by-distance, IBD, vs. isolation-by-resistance, IBR), and dispersal limit of species (200 km vs. 300 km). Higher dispersal limit generally had a positive but small influence on genetic diversity. Genetic distance increased with both geographic distance and landscape resistance, but landscape resistance displayed a stronger influence. Connectivity was positively related to genetic diversity under IBR but was less important under IBD. Fragmentation had a strong negative influence on the spatial patterns of genetic diversity and effective population size (Ns). Despite habitats being more concentrated and less widely distributed, the low-fragmentation landscape had greater genetic diversity than the high-fragmentation landscape, suggesting that highly concentrated but larger habitat patches may provide a genetic refuge for the Mexican spotted owl.

EFEKTIVITAS RUANG TERBUKA HIJAU SEBAGAI HABITAT BURUNG DI KOTA BOGOR DAN SEKITARNYA

Green open spaces can be potential habitats for birds in urban landscapes. Due to high number of land development, the green open spaces in urban landscapes tend to be small and scattered. Indeed, analysis about effectivity of green open spaces as bird habitats in Bogor City and its surroundings is needed. We investigated bird habitat patches on 14 locations in Bogor City and its surroundings. This study aimed to analyze the effectiveness of bird habitat patches for bird species richness using two variables (size and complexity). The data were analyzed using the Pearson Correlation and multiple linear regression. The results showed that there were no significant differences between bird species richness and size of patches. Conversely, there were significant differences between bird species richness and complexity of patches. The Pearson Correlation revealed that there were high correlation between bird species richness and complexity of patches. Finally, we propose three recommendations of green open spaces as bird habitat patches in Bogor City and its surroundings, such as protecting and managing both small and large bird habitat patches, increasing number of vegetation strata and number of vegetation in some strata in small bird habitat patches, and increasing number of vegetation in some strata in large bird habitat patch with low bird speciess richness.

Habitat Structure, Quality and Landscape Predict Species Richness and Communities of Collembola in Dry Grasslands in Austria.

We assessed the relationships between site size, habitat quality, landscape factors (fragmentation, landscape diversity) and species richness in communities of Collembola in 50 small dry grassland habitat patches in an agricultural landscape of eastern Austria. Grasslands in that region were once widespread and extensive, but have become increasingly fragmented and isolated. We hypothesized that dry grassland springtails species richness is significantly correlated with site variables (soil properties, habitat quality) and that the size of grassland sites is positively correlated with species richness. We used pitfall traps in 50 dry grasslands in differently structured agricultural landscapes and tested total abundance and three species richness measures: (1) the number of dry grassland specialist species; (2) total number of dry grassland species and (3) overall species richness. In the multivariate correlation models, we found that all species richness measures were significantly related to the plant species richness, a shape parameter of the sites, soil properties such as humus, temperature, sand and gravel content and the landscape variable reflecting isolation (distance to the nearest large dry grassland area). This landscape variable indicates that neighbouring grasslands are influencing the species richness of the sites. This may be a result of passive wind dispersal across the landscape or historic connection of the small sites with much larger dry grasslands. The size of the site did not show any significant correlation with total, dry grassland specialist, dry grassland generalist or generalist species richness. The small size of Collembola might explain these findings, because they have high population densities even in small patches.

Analysis of genetic diversity in a peatland specialist butterfly suggests an important role for habitat quality and small habitat patches

Understanding effects of habitat and landscape features on genetic variation is a prerequisite for the development of habitat and landscape management strategies aimed at conserving genetic diversity. While there has been considerable research on the effects of landscape structure on the genetics of populations, a recent review identified key biases in this body of work. The majority of landscape genetic studies investigate the intervening matrix’s influence on differentiation and gene flow among populations. Although characteristics of local habitat patches may be important determinants of genetic diversity, fewer studies have examined these relationships. Here we use node- and neighbourhood-based approaches to analyze correlates of genetic diversity in the bog copper (Lycaena epixanthe), a specialist butterfly endemic to temperate Nearctic peatlands that is threatened in parts of its range. Based on 190 repeatable and polymorphic amplified fragment length polymorphism loci, we found that genetic diversity was higher in habitat patches that were smaller and surrounded by more open water. Our results indicate that valuing small peatlands and preserving the surrounding water table may be important for conservation of genetic diversity in this highly specialized species. Our study highlights the importance of variables affecting habitat quality for conservation genetics.

The impact of asexual and sexual reproduction in spatial genetic structure within and between populations of the dioecious plant Marchantia inflexa (Marchantiaceae).

In dioecious plants, sexual reproduction requires close proximity to potential mates, but clonal growth can increase this distance and, therefore, reduce the probability of mating. Reduction in sexual propagules can lead to decreased dispersal and gene flow between populations. Gene flow and clonal growth may be further influenced by the size of the habitat patch. The effects of habitat size and reproductive mode (sexual or asexual reproduction) on spatial genetic structure and segregation of the sexes were tested by quantifying the distributions of genotypes and the sexes using the dioecious liverwort Marchantia inflexa. Plants were sampled from five pairs of small-large habitat patches to identify within- and among-population spatial genetic structure using 12 microsatellite markers. Spatial distributions were calculated as the likelihood that pairs of individuals were the same sex or genotype, and it was determined how that likelihood was affected by habitat patch size (small/large). Asexual reproduction dominates within populations, and asexual dispersal also occurred across populations. Spatial segregation of the sexes was observed within populations; males were more likely to be near individuals of the same sex than were females. Although the likelihood of both sexes being near members of the same sex was similarly greater on small habitat patches, on large habitat patches male genotypes were almost 15 % more likely to be near clonemates than were female genotypes. The results show a sex difference in clonal clumping that was dependent upon habitat size, suggesting differential colonization and/or survival between males and females. The sexes and genotypes being structured differently within and among populations have implications for the persistence of populations and the interactions between them. This study demonstrates that studying only the sexes and not their genotypes (or vice versa) can limit our understanding of the extent to which reproductive modes (sexual or asexual) influence genetic structure both within and between populations.

Abundance and survival rates of three leaf-litter frog species in fragments and continuous forest of the Mata Atlântica, Brazil

Habitat destruction and fragmentation alter the quality of habitats and put populations under the risk of extinction. Changes in population parameters can provide early warning signs of negative impacts. In tropical forests, where habitat loss and fragmentation are vast, such indicators are of high relevance for directing conservation efforts before effects are irreversible. Most of our knowledge from tropical ecosystems originates from community level surveys, whereas our understanding of the influence of habitat conversion on vital rates of species is limited. This study focused on the influence of anthropogenic habitat fragmentation on the survival probability and abundance of three leaf-litter frog species (Rhinellaornata, Ischnocnemaguentheri and I.parva) in forest patches of the Atlantic rainforest of South-east Brazil compared to a continuous forest. The species differ in their matrix tolerance: high for R.ornata and low for I.guentheri and I.parva and, thus, we examined whether their survival and abundance correspond to this classification. Ischnocnemaguentheri showed highest abundances in all study sites and low mortality in the forest patches compared to the continuous forest; I.parva was encountered only in isolated fragments, with very low mortality in one isolated fragment; and the matrix tolerant species had generally low abundance and showed no clear pattern in terms of mortality in the different sites. Our counter-intuitive results show that even matrix sensitive amphibian species may show high abundance and low mortality in small forest patches. Therefore, these patches can be of high value for amphibian conservation regardless of their degree of matrix aversion. Landscape level conservation planning should not abandon small habitat patches, especially in highly fragmented tropical environments.

Habitat selection by the black-tufted marmosetCallithrix penicillatain human-disturbed landscapes

Abstract:There are several primate species with high risk of extinction in small forest fragments disturbed by human activities. However, some species exhibit high ecological plasticity, which allows them to persist in human-modified landscapes. The main goal of this study is to examine the relative roles of vegetation (mean distance among trees and mean canopy cover), human disturbance (distance to the road, distance to the fragment edge and edge type), and habitat spatial configuration (spatial autocorrelation index, category of quadrat – position within the fragment/fragment type) on the habitat selection of the black-tufted marmosetCallithrix penicillatain forest patches. We selected forest patches near and away from roads/urban areas, in southern Minas Gerais state, south-eastern Brazil. We used generalized linear mixed models to explain the presence of black-tufted marmoset in those patches. Our results show that black-tufted marmoset tend to occupy forest fragments closer to roads/urban areas, and consequently are under the influence of anthropic disturbance. In addition to the area delimited by these fragments, there is a preference for edge environments, where disturbances are exacerbated and the ecological conditions are suitable for exploitation by the black-tufted marmoset (supply of gum trees and reduced risk of competition). We suggest that a cross-habitat spillover by marmoset occur from forests to small habitat patches close to human-modified areas, such as those in proximity to roads and urban zones.

EFEKTIVITAS RUANG TERBUKA HIJAU SEBAGAI HABITAT BURUNG DI KOTA BOGOR DAN SEKITARNYA

Green open spaces can be potential habitats for birds in urban landscapes. Due to high number of land development, the green open spaces in urban landscapes tend to be small and scattered. Indeed, analysis about effectivity of green open spaces as bird habitats in Bogor City and its surroundings is needed. We investigated bird habitat patches on 14 locations in Bogor City and its surroundings. This study aimed to analyze the effectiveness of bird habitat patches for bird species richness using two variables (size and complexity). The data were analyzed using the Pearson Correlation and multiple linear regression. The results showed that there were no significant differences between bird species richness and size of patches. Conversely, there were significant differences between bird species richness and complexity of patches. The Pearson Correlation revealed that there were high correlation between bird species richness and complexity of patches. Finally, we propose three recommendations of green open spaces as bird habitat patches in Bogor City and its surroundings, such as protecting and managing both small and large bird habitat patches, increasing number of vegetation strata and number of vegetation in some strata in small bird habitat patches, and increasing number of vegetation in some strata in large bird habitat patch with low bird speciess richness.

Landscape connectivity and the role of small habitat patches as stepping stones: an assessment of the grassland biome in South America

Connectivity losses lead to a reduction of the amount of habitat resources that can be reached and used by species, and hence to a decline in the ranges and abundance of multiple taxa. Despite the recognized important role of small habitat patches for many species inhabiting fragmented landscapes, their potential contribution as stepping stones for maintaining overall landscape connectivity has received less attention. Using connectivity metrics based on a graph-theoretic approach we (i) quantified the connectivity of grassland patches in a sector of the Pampa region in Argentina, using a range of dispersal distances (from 100 to 10,000 m) representative of the scale of dispersal of different species; (ii) identified the most relevant patches for maintaining overall connectivity; and (iii) studied the importance of small patches (defined for different area thresholds of 5, 20, and 50 ha) as connectivity providers in the landscape. Although grassland patches were in general poorly connected at all distances, some of them were critical for overall connectivity and were found to play different crucial roles in the patch network. The location of small patches in the grassland network allowed them to function as stepping stones, yielding significant connectivity gains for species that move large distances (>5000 m) for the three area thresholds considered. Thus, under the spatial pattern of the studied landscape, species that move long distances would benefit from stepping stones, while less mobile organisms would benefit from, and mostly rely on the largest patches. We recommend that future management activities should (i) aim at preserving the grassland patches with the highest potential as stepping stones to promote landscape-level connectivity; and (ii) pay more attention to the conservation of key small patches, particularly given that usually they are those more vulnerable to land clearing for agriculture.

The role of small secondary biotopes in a highly fragmented landscape as habitat and connectivity providers for dragonflies (Insecta: Odonata)

Habitat loss and degradation are considered major threats to freshwater biodiversity and to invertebrates in particular. These often irreversible processes may lead to local and regional extinctions of species, most notably of stenotopic taxa. In spite of this, a number of studies have shown that small habitat patches can sustain rich and abundant communities. The present work assesses the relevance of a group of four small man-made (secondary) wildlife ponds to Odonata species diversity and abundance. Results obtained on pond recruiting capacity, species richness, abundance and habitat use by means of exuviae collection and monitoring of adults using a capture–mark–recapture (CMR) method indicate the potential suitability of these small aquatic biotopes and the surrounding landscape as habitat providers and stepping stone connectors in the Valles lowlands (Catalonia, Spain). This region, close to the metropolitan area of Barcelona, has severely degraded natural habitats and high landscape fragmentation due to infrastructure, urban and industrial expansion. A comparison among a greater number of sites (ponds and sections of streams and rivers) distributed across the region showed that adequately managed small waterbodies harbour richer Odonata communities than others that are unmanaged or managed specifically for other types of fauna or uses. Appropriate care of these small biotopes avoids disturbance and keeps them free from vertebrates like fish and waterfowl which, under certain conditions, may have a strong influence on the invertebrate communities because, apart from feeding on larvae, they may have a negative impact on macrophyte development and water quality. While rivers and streams, the only natural aquatic habitats in the area, may be both expensive and technically challenging to restore and manage successfully, the creation and/or restoration of small ponds and short river sections in suitable locations can be a cost-effective method for enhancing freshwater vegetation and invertebrate diversity in this impacted landscape.

Landscape genetics highlight the importance of sustainable management in European mountain spruce forests: a case study on Western capercaillie

The mountain spruce forests of the Western Carpathians have experienced a dramatic deterioration in the last decades increasing the landscape fragmentation. This considerably affected the Western capercaillie population recently surviving within small habitat patches surrounded by unfavourable habitats. Our study shows that the long-term isolation resulted in genetic differentiation with decreasing trend in allelic richness towards the most adjacent western subpopulations. We evaluated dispersal possibilities within the landscape and identified barriers and the most critical corridors between genetically distinct subpopulations. Landscape genetic analysis confirmed that the isolation by environmental features explains the observed genetic patterns better than straight geographical distance. We highlight the urgent need for an active conservation management in the critical habitats where dispersion might be constrained or “bottlenecked” in order to ensure gene flow within the fragmented capercaillie metapopulation of the Western Carpathian mountain forests.