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Species with different ecological niches will likely exhibit distinct responses to a changing environment. Differences in the magnitude of niche specialization may also indicate which species may be more vulnerable to environmental change, as many life-history characteristics are known to affect climate change vulnerability. We characterized the niche space of three sympatric high-elevation ground-dwelling squirrels, yellow-bellied marmot (Marmota flaviventer), Belding's ground squirrel (Urocitellus beldingi), and golden-mantled ground squirrel (Callospermophilus lateralis), in the alpine and upper subalpine regions of the Sierra Nevada in California. We used 5879 observations of individual squirrels, collected from 4 years (2009-2012) of transect survey data, to quantify which ecogeographical variable types (climate, topography, or landcover) were most important in defining the niche of each species. We conducted Ecological Niche Factor Analysis to quantify the niche and generate indices of "marginality" (magnitude of selection) and "specialization" (narrowness of niche space). All three species demonstrated differential use of niche space when compared to the available niche space. Moreover, the relative importance of the variables shaping the niche differed among these species. For example, the presence of meadows was important in defining the niche for U. beldingi and M. flaviventer, but the presence of conifers was important to C. lateralis. Precipitation was important in defining the niche for all three species, positively so for U. beldingi, and negatively for the other two species. The niche breadth of these three species was also positively associated with geographic range size. Mammals in high-elevation mountain systems often are perceived as vulnerable to climate shifts, but our results underscore the importance of also including non-climate-based factors in defining the niche. The overall magnitude of niche selection for all three species was driven by a combination of topographic, climatic, and landcover factors; thus, efforts to forecast areas where these species can persist in the future need to evaluate from more than just a climatic perspective.

Based on long-term (2010–2014) studies carried out in the forest ecosystems of the Central Forest Biosphere Reserve, two models of the spatial niche of the bank vole (Myodes glareolus Schreber, 1780) were constructed using factor analysis (ENFA). Models with a sufficient level of quality characterize the characteristics of the species' niche. The modeling results make it possible to describe the structure of the optimal habitat for the bank vole in mosaic southern taiga forests at different levels (scales) of spatial organization. [ABSTRACT FROM AUTHOR]

Understanding drivers of space use and habitat selection is essential for management and conservation, especially under rapid environmental change. Here, we develop summer and winter habitat suitability models for the endemic wild Svalbard reindeer (Rangifer tarandus platyrhynchus). The High Arctic Svalbard tundra is currently subject to the fastest temperature increases on Earth, and reindeer spatial responses to associated environmental change are strongly restricted due to landscape barriers (including 60% glacial coverage) and lack of sea ice as movement corridors. We used an extensive dataset of GPS-collared adult females (2009–2018; N = 268 individual-years) to model seasonal habitat selection as a function of remotely sensed environmental variables , and subsequently built habitat suitability models using an ensemble modelling framework. As expected, we found that reindeer preferred productive habitats, described by the normalized difference vegetation index (NDVI) and plant biomass (derived from a vegetation map), in both seasons. This was further supported by selection for bird cliff areas, rich in forage, improving habitat suitability especially in winter. Contrary to our expectations, the terrain variables had similar, impact on habitat suitability in the two seasons, except for use of higher elevations in winter, likely related to improved forage access due to less snow. Suitable habitat patches covered only a small proportion of the landscape and were highly clustered in both seasons. About 13.0% of the total land area was suitable in both seasons, while summer-only and winter-only areas contributed a marginal addition of around 4.7% and 1.5%, respectively. This suggests, that unlike many continental and migratory Rangifer populations, even small geographic areas may encompass suffiscient suitable habitat. These first archipelago-wide habitat suitability models provide seasonal baseline maps relevant for the management and conservation of Svalbard reindeer, particularly under rapid environmental alterations from climate change.

The risk of large carnivore mortality from anthropogenic sources is increased in areas where frequent human-carnivore encounters are high. Translocation is a potential tool for reducing these conflicts and re-establishing wild populations. Determining proper translocation sites for tigers is important for securing their future. In this research, we quantitatively evaluated the habitat suitability of a potential tiger translocation area on the Kampar Peninsula, a large peatland landscape in Sumatra. This landscape is essential for the conservation of the local tiger population, but its role as a tiger habitat has rarely been investigated. We conducted this research in a region with mosaicked land-use types covering an area of 7,045.89 km2. We applied species ecological niche factor analysis (ENFA) to model habitat suitability using species presence and ecogeographical variables as the bases. The model predicted that approximately 60% of the study area is tiger-suitable habitat with varying suitability levels. The tiger habitat characteristics in the study region are dissimilar to the global tiger habitat characteristics, and the high specialization value obtained indicates that tigers inhabit very narrow niches. Considering the low density of tigers in peatlands, we estimate that the carrying capacity of the whole Kampar landscape is approximately 13 tigers. Therefore, to conserve a viable tiger population, it is necessary to maintain connectivity between the Kampar peatlands and the Kerumutan landscape situated to the south of the Kampar Peninsula. [ABSTRACT FROM AUTHOR]

Maps of potential biodiversity are prominent tools for regional conservation planning because they allow to quantify the diversity of species that potentially inhabit different habitats. These maps are constructed from modeling species ecological niches based on the association between the geographical localities where species were detected and the environmental variables at those localities. Previous researches addressed the development of MPB for administrative regions using regional species distributions data to modeling ecological niches, which may lead to flawed predictions on potential biodiversity. Our aim is to assess the consequences of failing to include all available records on full species distribution to develop MPB. As a study case, we produced two MPBs for an administrative region of Argentina using RSD and FSD data sets of 14 species of insects and performed Environmental Niche Factor Analysis to model their ecological niches. Our results evidenced that both MPB were not spatially congruent in their predictions on potential biodiversity, because the ecological niches represented by RSD and FSD data were different in their position and volume. We found that the MPB based on RSD data may underpredict the potential biodiversity of distinct habitats at the landscape level, and that the use of this map may underestimate areas with different conservation potential within an administrative region. These results suggest that the choice of the extent of geographic records used to construct the MPB strongly conditions the quality and credibility of these maps. [ABSTRACT FROM AUTHOR]

The article presents the results of ecological niche and habitat suitability modelling of Ursus arctos, performed in the Central Forest State Nature Reserve and its buffer zone (Tver region, Russia), using the GNESFA factor analysis method. Briefly discussed are the basic rules for performing such a study, approaches and modelling techniques. The ecological niche was modelled using FANTER, ENFA and MADIFA. The habitat suitability was modelled using Mahalanobis distances analysis. As ecogeographical variables, vegetation indices, morphometric characteristics of the relief, proximity rasters and types of landscape cover were used. The presence points of the species were recorded on permanent routes using a GPS navigator during 2008–2018. As a final result, six models with a different combination of input data (presence points and environmental variables) were selected. As a set of independent test data, we used U. arctos' presence points recorded by the forest rangers and research staff. The scenarios of the influence of utilisation weights on presence points and multicollinearity on variables are separately modelled. The global marginality of the best model was 1.17, while the tolerance was 0.69. The distance to anthropogenic food sources, the NDVI and the projective cover of grasslands made the highest contribution along the marginality axis. In the first three axes of specialisation, coniferous forests, Sphagnum pine (Pinus sylvestris) forests, and the distance to the rivers made the largest contribution. AUC values ranged from 0.66 to 0.73. Values of the continuous Boyce index were from 0.85 to 0.93. The area of the partially violated buffer zone turned out to be more suitable for U. arctos than the inner area of the Central Forest State Nature Reserve. Utilisation weights and the number of ecogeographical variables had a significant impact on the results of all analyses.

The increasing threat of vector-borne diseases (VBDs) represents a great challenge to those who manage public and animal health. Determining the spatial distribution of arthropod vector species is an essential step in studying the risk of transmission of a vector-borne pathogen (VBP) and in estimating risk levels of VBD. Risk maps allow better targeting surveillance and help in designing control measures. We aimed to study the geographical distribution of Culicoides imicola, the main competent vector of Bluetongue virus (BTV) in sheep in Tunisia. Fifty-three records covering the whole distribution range of C.imicola in Tunisia were obtained during a 2-year field entomological survey (August 2017 – January 2018 and August 2018 – January 2019). The ecological niche of C. imicola is described using ecological-niche factor analysis (ENFA) and Mahalanobis distances factor analysis (MADIFA). An environmental suitability map (ESM) was developed by MaxEnt software to map the optimal habitat under the current climate background. The MaxEnt model was highly accurate with a statistically significant area under curve (AUC) value of 0.941. The location of the potential distribution of C. imicola is predicted in specified regions of Tunisia. Our findings can be applied in various ways such as surveillance and control program of BTV in Tunisia.

Background. Ecological niche and the habitat suitability modeling is becoming an increasingly important tool for finding the relationship of organisms with their habitat and refining data on their distribution. This work demonstrates some of the possibilities of such modeling for small mammals in stationary captures. Materials and methods. The work was carried out in the Central Forest Nature Reserve. The data from the captures of bank and red voles on the trap line for 2010–2014 were taken as the presence points, and 9 environmental variables were used as predictors. The modeling was carried out using a comprehensive approach, within the framework of which ecological niches of voles were modeled using ecological niche factor analysis, as well as habitat suitability maps using it and analyses by Mahalanobis distances. Results. The bank vole showed a low marginality index (0,56) and a relatively high tolerance index (0,68). The environmental conditions used by the species were slightly different from the average available conditions. Its suitable habitats were associated with relief elevations and watershed surfaces. The red vole had a high marginality index (1,39) and a low tolerance index (0,37). It is confined to a narrow range of preferred habitats: boreal spruce forests on elevated watersheds. Habitats suitable for voles are segregated, but not completely, showing partial overlap in the area of boreal spruce forests at elevations. Schoener's D-index value of niche overlap was 0.79. Conclusions. The ecological niches of the two forest vole species differed, which is associated with the peculiarities of habitat confinement. A significant overlap of areas of suitable habitats of the two species may be associated with incomplete mapping of the ecological relationships of the bank vole due to the insufficient representativeness of the trap line.

Masting is a complex mechanism which is mainly driven by a combination of internal plant resources and climatic conditions. While the driving role of climate in masting is being intensively studied, the interplay among climate, seed production, vegetation growth and phenology still needs further investigation. The objectives of this study were to identify the climatic determinants of different levels of seed production and of NDVI-based vegetation growth and phenology in European beech, and to evaluate if exists a trade-off between these two plant processes. To answer these questions, we used a 25-year-long dataset of beech seed production. We exploited the concept of ecological niche assuming that a mast year can be modeled like a species with variable preferences for different resources, which are the underlying annual climatic conditions; we performed an Ecological Niche Factor Analysis (ENFA), a presence-only modeling tool conventionally used in zoology and botany, and used seasonal (spring, summer, autumn) Standardized Precipitation-Evaporation Index (SPEI) observations, considering the current year (y−0), and up to one (y−1) and two (y−2) years before the masting event. For analyzing the role of vegetation growth and phenology, we used seasonal Normalized Difference Vegetation Index (NDVI) values and associated NDVI-based phenological metrics derived from Landsat imagery. Results indicated the driving role of climate for masting, especially in VHSP years. A moist summer and dry spring at y−2 and a dry summer at y−1 represented the main driving climatic conditions for masting; while a moist spring during the observation year represented the key condition for triggering higher intensities of seed production. Summer NDVI at y−0 and y−1 represented the variables discriminating best between masting and non-masting years and resulted as driven by opposite summer climatic conditions than seed production, thus indicating a trade-off between seed production and vegetation phenology. We concluded that reproduction and vegetation growth act as two different climate-dependent plant responses in beech, in a way that certain conditions through the years promote mast seeding and the opposite conditions favor vegetation growth. The understanding of climate-growth-masting relationships represents indispensable knowledge for providing a holistic view of masting mechanisms and developing adaptive forest management strategies in this species.

Invasive species have a massive impact on their environment and predicting geographical zones at risk of invasion is paramount to the control of further invasions. Invasive anurans are particularly detrimental to native amphibian species, other vertebrates, and even aquaculture through competition, predation, disease transmission, toxicity, or a combination of these. Four species have been designated as the worst anuran invaders worldwide: Duttaphrynus melanostictus, Rhinella marina, Lithobates catesbeianus and Xenopus laevis. In this study, we modelled global habitat suitability for all four species using ecological niche factor analysis (ENFA) to predict the most susceptible areas to invasion. Models showed suitable climatic conditions for all four species expanded beyond their current native and invasive ranges. Tropical, subtropical, and island biomes around the world were among the areas with the highest ENFA suitability for all four species. Further, marginality statistics indicate niche expansion in D. melanostictus, and generalism in the three other species. As only climatic variables were used in the modelling, these results show the ultimate distributions if all landscape conditions are met without significant barriers to invasion.

The increasing threat of vector-borne diseases (VBDs) represents a great challenge to those who manage public and animal health. Determining the spatial distribution of arthropod vector species is an essential step in studying the risk of transmission of a vector-borne pathogen (VBP) and in estimating risk levels of VBD. Risk maps allow better targeting surveillance and help in designing control measures. We aimed to study the geographical distribution of Culicoides imicola , the main competent vector of Bluetongue virus (BTV) in sheep in Tunisia. Fifty-three records covering the whole distribution range of C.imicola in Tunisia were obtained during a 2-year field entomological survey (August 2017 – January 2018 and August 2018 – January 2019). The ecological niche of C. imicola is described using ecological-niche factor analysis (ENFA) and Mahalanobis distances factor analysis (MADIFA). An environmental suitability map (ESM) was developed by MaxEnt software to map the optimal habitat under the current climate background. The MaxEnt model was highly accurate with a statistically significant area under curve (AUC) value of 0.941. The location of the potential distribution of C. imicola is predicted in specified regions of Tunisia. Our findings can be applied in various ways such as surveillance and control program of BTV in Tunisia. [ABSTRACT FROM AUTHOR]

Habitat degradation has caused a significant threat to wildlife, particularly to megafauna including the Asian elephant that has a large home range. Recolonization of Asian elephants in 1994 in and around Bardia National Park (BNP) has provided a unique study setting to address habitat change over two decades (1990–2013). Elephant presence data in 2013 was modeled using Ecological Niche Factor Analysis (ENFA), which identified the influential ecogeographical variables for elephant habitat. These variables were further used in a regression model to determine habitat suitability for 1990. We found that elephant suitable habitat has been lost between pre-recolonization (1990) and the year 2013 in and around BNP. Unsuitable elephant habitat increased overall by 22% in Bardia District and 20% inside BNP. Central to elephant habitat loss has been a large human population growth, re-forestation efforts with an increase in sal forests, and elephant alteration of vegetation by grazing. Available suitable habitat for elephants in and around BNP should be conserved and managed to prevent further degradation for the maintenance of the elephant population, which will help mitigate human-elephant conflict in the region.

Abstract Background Biting aquatic insects belonging to the order Hemiptera have been suggested as potential vectors of Mycobacterium ulcerans in endemic areas for Buruli ulcer (BU). If this is the case, these insects would be expected to co-exist with M. ulcerans in the same geographical areas. Here, we studied the geographical distribution of six aquatic Hemiptera families that are thought to be vectors of M. ulcerans and explored their potential geographical overlapping with communities reporting BU cases in endemic countries. Methods We have developed ensemble ecological models of predicted distribution for six families of the Hemiptera (Naucoridae, Belostomatidae, Notonectidae, Nepidae, Corixidae and Gerridae) applying a robust modelling framework over a collection of recorded presences and a suite of environmental and topographical factors. Ecological niche factor analysis (ENFA) was first used to identify factors that best described the ecological niches for each hemipteran family. Finally, we explored the potential geographical co-occurrence of these insects and BU in two endemic countries, Cameroon and Ghana. Results Species of the families Naucoridae and Belostomatidae, according to our models, are widely distributed across Africa, although absent from drier and hotter areas. The other two families of biting Hemiptera, the Notonectidae and Nepidae, would have a more restricted distribution, being more predominant in western and southern Africa. All these four families of biting water bugs are widely distributed across coastal areas of West Africa. They would thrive in areas where annual mean temperature varies between 15–22 °C, with moderate annual precipitation (i.e. 350–1000 mm/annual) and near to water courses. Species of all hemipteran families show preference for human-made environments such as agricultural landscapes and urbanized areas. Finally, our analysis suggests that M. ulcerans and species of these aquatic insects might coexist in the same ecological niches, although there would be variation in species diversity between BU endemic areas. Conclusions Our findings predict the geographical co-existence of some species of aquatic hemipteran families and BU. Considering the existing biological evidence that points to some of these aquatic insects as potential phoretic vectors of M. ulcerans, its presence in BU endemic areas should be considered a risk factor. The ecological models here presented may be helpful to inform future environmental based models intended to delineate the potential geographical distribution of BU in the African region.

Abstract Introduction Huemul (Hippocamelus bisulcus Molina) is the most threatened flag species of Southern Patagonia, where conservation efforts were not effective to avoid the retraction of its distribution area. Habitat quality modeling can assist to design better management strategies for regional conservation planning. The objective was to elaborate one habitat suitability map for huemul, defining the environmental characteristics at landscape level, and determining the distribution of the suitable habitat inside the current natural reserve network. Methods We used a database of 453 records and explored 40 potential explanatory variables (climate, topographic, and landscape variables including human-related ones) to develop one habitat suitability map using the Environmental Niche Factor Analysis (ENFA) for Santa Cruz province (Argentina). We combined the outputs in a GIS project using different shapes, including the current natural reserve network. Results We defined the potential habitat for huemul, where forest edges and ecotone zones (e.g., mainly alpine environments) were the most important environmental variables, as well as some forest types (e.g., Nothofagus pumilio). Habitat losses were found in the extreme potential distribution areas (northern and southern areas), probably related to the increasing ranch activities. The current natural reserve network maintains approximately half of the huemul potential habitat in Santa Cruz province, where National Parks presented the similar conservation importance than the Provincial natural reserves. Conclusions Habitat suitability model for huemul can be used as a decision support system for new management strategies at different landscape levels to improve the current conservation efforts.

Abstract Background Numerous species, especially among rodents, are strongly affected by the availability of pulsed resources. The intermittent production of large seed crops in northern hemisphere tree species (e.g., beech Fagus spec.,oak Quercus spec., pine trees Pinus spec.) are prime examples of these resource pulses. Adult edible dormice are highly dependent on high energy seeds to maximize their reproductive output. For juvenile dormice the energy rich food is important to grow and fatten in a very short time period prior to hibernation. While these erratic, often large-scale synchronized mast events provide overabundant seed availability, a total lack of seed production can be observed in so-called mast failure years. We hypothesized that dormice either switch territories between mast and non-mast years, to maximize energy availability or select habitats in which alternative food sources are also available (e.g., fleshy fruits, cones). To analyze the habitat preferences of edible dormice we performed environmental niche factor analyses (ENFA) for 9 years of capture-recapture data. Results As expected, the animals mainly used areas with high canopy closure and vertical stratification, probably to avoid predation. Surprisingly, we found that dormice avoided areas with high beech tree density, but in contrast preferred areas with a relatively high proportion of coniferous trees. Conifer cones and leaves can be an alternative food source for edible dormice and are less variable in availability. Conclusion Therefore, we conclude that edible dormice try to avoid areas with large fluctuations in food availability to be able to survive years without mast in their territory.

The role of understory plants in native forests is critical for ecosystem function, wildlife protection and ecosystem productivity. The interest to estimate biodiversity increased during the last decades at landscape level. The objective was to elaborate a map of potential biodiversity (MPB) of understory species of Nothofagus forest using potential habitat suitability maps (PHS) of 15 plants in Santa Cruz province, Argentina. Additionally, we asked the following questions: (i) Were plant species differentially distributed according to the forest types?, (ii) do forest types represent different plant species assemblage with specific ecological niche requirements?, and (iii) is it possible to detect hotspots in the MBP according to the forest types? We used 721 plots database of vascular plants, from where 15 indicator species were identified. The assemblage species for different forests (Nothofagus antarctica , N. pumilio and evergreen mixed) were analysed using a detrended correspondence analysis. Also, we explored 41 potential explanatory variables to develop PHS, and combined these maps to obtain one MPB (1–100%). Finally, we analysed the outputs into a GIS through different landscapes alternatives to detect hotspot areas. Marginality and specialization values allowed identifying species assemblage that presented similar variability in the habitat requirements. MPB varied across the landscape, with higher values in the south and lower values near glaciers. MPB had the highest values in N. antarctica forest with >50% cover at landscape level. N. antarctica present more hotspots than N. pumilio forests, mainly in the south, compared to mixed evergreen forests which present few hotspots near glaciers. These results can be used as a tool to design new management and conservation strategies at landscape level. Unlabelled Image • Habitat suitability models allowed define habitat requirement for studied species. • Map of potential biodiversity synthetizes the information for the indicator species. • Understory potential biodiversity changed across the different forest types. • Nothofagus antarctica forest presented the highest potential biodiversity. • Ecotone areas with different vegetation types supported more potential biodiversity. [ABSTRACT FROM AUTHOR]

Context: Effective biodiversity conservation requires information about a species' ecology and its relationship with the geographical context. To achieve this efficiently, species distribution models can be developed, also taking into account species associations. Aims: I aimed to illustrate the habitat requirements of two threatened passerines of semi-open landscapes, i.e. the lesser grey shrike, Lanius minor , and the woodchat shrike, Lanius senator , in southern Italy. Further, I assessed whether there is heterospecific social attraction between them, by assessing how their habitat niches overlap. Methods: Data were collected by territory mapping during the 2009–13 breeding seasons. The habitat requirements of the species were investigated with the help of ecological niche factor analysis (ENFA). In addition, the areas of sympatry between the two species were defined by indicator kriging and the habitat niche overlap was analysed using the generalised linear model (GLM). Key results: The results showed that these two species inhabit open areas, with scattered vegetation such as shrubs and trees, while avoiding intensively cultivated permanent crops, such as vineyards and olive groves. Moreover, a little difference was observed in the percentage cover of shrublands, which were higher in the woodchat shrike territories than in the lesser grey ones. The strong overlap in their habitat niches suggests heterospecific social attraction between them, especially because of the species rarity. Conclusions: The lesser grey and the woodchat shrike were found to occur in very similar environments, by evidencing the overlap of their macrohabitat niches. This suggests the presence of heterospecific social attraction, corroborating the understudied hypothesis that this phenomenon is valid for migrant birds as well. The lesser grey shrike, in particular, may use occurrences of the woodchat shrike as a cue for assessing habitat quality and, thus, to establish its territory. Implications: Considering the high habitat niche overlap, habitat changes occurring in the landscape might affect them equally. Furthermore, the use of heterospecific social information in habitat selection potentially has many important conservation implications. Indeed, by reproducing the appropriate information, birds could be attracted to specific sites known to be high-quality habitat. Steppic birds are among the most threatened bird species in Europe; so, to achieve their conservation is essential to know their habitat requirements and their spatial ecology. The present paper illustrates the habitat requirements of two threatened steppic migrant birds and that their niche overlap explains heterospecific social attraction between them. [ABSTRACT FROM AUTHOR]

Balkan chamois (Rupicapra rupicapra balcanica) is a protected species with an Inadequate-Bad (U2) conservation status in Greece. Our study explores its seasonal range use pattern, demography and habitat selection in a site of the Natura 2000 network, Timfi Mountain. To this aim, we examined 1168 observations obtained from six seasonal surveys (2002: four seasons, 2014 and 2017: autumn) and performed an ecological-niche factor analysis (ENFA), using 16 environmental and human-disturbance variables. The species had an annual range of 6491 ha (25% of the study area), followed the typical range-use pattern, and presented the minimum core area during the rutting season (autumn). Timfi Mt hosted 469 individuals in 2017 (the largest population in Greece), increasing by 3.55 times since 2002. The species selected higher altitudes during summer and autumn, pinewoods over broad-leaved woods as winter grounds, and it avoided south-facing slopes. Our results supported the anthropogenic risk avoidance hypothesis; the species always selected remote areas away from roads, human settlements, and hunting grounds. In Greece, 40% of its distribution area falls within hunting ban areas (16.5% of the country). A national conservation policy is needed towards maintaining and increasing roadless areas and hunting-ban areas within Balkan chamois range nationwide.

The distribution of biodiversity at the landscape level is shaped by biotic, abiotic and anthropogenic factors. Biodiversity maps provide the basis for defining management and conservation strategies that can minimize human impacts. The objective was to elaborate a map of potential biodiversity of lizards based on habitat suitability maps of individual species in Santa Cruz (Argentina). Also, we analysed desertification influence and the representativeness of the current network of protected areas on the lizard biodiversity. For this, we used a database of eight lizard species and we explored 41 potential explanatory variables to develop habitat suitability maps, which were combined to obtain one single map of the potential biodiversity. We analysed the outputs in a GIS project using the marginality and the specialization indexes and the normalized difference vegetation index of each species. Also, we characterized the potential biodiversity using the following variables: desertification, ecological areas and current network of protected areas. We detected differences in the occupied niches for the different species throughout the landscape. The map of potential biodiversity uncovered hotspots of biodiversity in the north-east study area, where the prevalence of unique climatic conditions showed a dry steppe and a high degree of desertification due to the human impacts (e.g. livestock). These results can be readily used as a support system for conservation and management strategies at different scale levels in areas with higher human impacts or to develop new protection areas. [ABSTRACT FROM AUTHOR]

In 1997, Eurasian Eagle Owls Bubo bubo returned to Limburg, the south-eastern province of The Netherlands. However, since then the population size has stagnated, while extremely high concentrations of PCBs have been found in Eagle Owl carcasses. These observations suggest that a further expansion of the species in Limburg is under threat. The high concentrations of toxic substances may be explained by the Eagle Owls' position at the top of the food chain. Studying their hunting behaviour may help to identify possible sources of poisoning. Identifying the most important habitat characteristics of hunting grounds is a first step towards recognizing poisoning sources. For this purpose, and to gain general insight into their habitat use, a GPS tracking study was conducted on six adult Eagle Owls from three adjoining territories in 2010-2011. We found that the quarries in the region are important for the Eagle Owls since they are used as nesting sites. Other habitat characteristics that attract the species are pastures, differences in altitude, forest edges and water bodies. Major roads and town centres are avoided. The highlighted areas and habitat characteristics provide information about the most important hunting habitats of Eagle Owls and insight into the underlying causes threatening this species in Limburg. [ABSTRACT FROM AUTHOR]

Using 30 Gazella subgutturosa subgutturosa presence-only data related to maximum entropy (Maxent) and ecological niche factor analysis (ENFA) models, but gained from field surveys, the present study was an attempt to assess how the Persian gazelle (subgutturosa) was distributed in Bamoo National Park located in Shiraz, Iran. While Maxent is thought to be predictive of satisfaction of environmental requirements, ENFA is considered as a tool for investigating the niche and habitat preferences of the species. All of the analyses by the models demonstrated the species distribution and the subgutturosa habitat. According to Maxent, vegetation, trough, and predator were witnessed to be most influential in the distribution, whereas ENFA revealed that elevation and vegetation were of highest value in terms of Gazella subgutturosa subgutturosa distribution. Interestingly enough, the predator variable was found to be highly contributing by Maxent but avoidable by ENFA. Also, the prediction level of the models turned out to be higher than chance occurrence under curve (AUC) = 0.5. [ABSTRACT FROM AUTHOR]

With the aim of solving the detection problems for current complex event detection models in detecting a related event for a complex event from the high proportion disordered RFID event stream due to its big uncertainty arrival, an efficient complex event detection model based on Extended Nondeterministic Finite Automaton (ENFA) is proposed in this paper. The achievement of the paper rests on the fact that an efficient complex event detection model based on ENFA is presented to successfully realize the detection of a related event for a complex event from the high proportion disordered RFID event stream. Specially, in our model, we successfully use a new ENFA-based complex event detection model instead of an NFA-based complex event detection model to realize the detection of the related events for a complex event from the high proportion disordered RFID event stream by expanding the traditional NFA-based detection model, which can effectively address the problems above. The experimental results show that the proposed model in this paper outperforms some general models in saving detection time, memory consumption, detection latency and improving detection throughput for detecting a related event of a complex event from the high proportion out-of-order RFID event stream. [ABSTRACT FROM AUTHOR]

Abstract. Using data on the known Iberian distributions of 10 species of Lepidoptera listed in the Habitats Directive referenced to the 10 × 10 km UTM grid, we determined their potential distributions and their relationships with selected bioclimatic factors associated with mean temperature and precipitation using Ecological Niche Factor Analysis (ENFA). Scores for Specialization and Marginality were determined in order to evaluate the relationships between the predictions of the model and climatic factors. The number of squares on the Iberian Peninsula in which the species are recorded and those squares predicted to be favourable for these species were determined if they matched the network of Protected Natural Areas. This suggested that a further eight 10 × 10 km squares should be included in Protected Natural Areas. The results also indicate that climate determines the distributions of most of the species. Although overall there is a close association between the observed and predicted distributions, the less thoroughly documented geographic ranges (i.e. those of the moth species) depart from this pattern.

Habitat preference of the meridional serotine bat Eptesicus isabellinus (Temminck, 1840) in semiarid Mediterranean landscapes Several molecular studies have recently reported the presence of a second species of the genus Eptesicus in the Iberian peninsula, the meridional serotine bat, E. isabellinus. This species is present in the south of Iberia and it seems to have an allopatric distribution with its twin species, E. serotinus. Ecological studies are now needed to understand the biology of E. isabellinus in southeast Spain. In this study, we used presence–only data for E. isabellinus to perform an ecological niche factor analysis (ENFA) and to create a habitat suitability map (HSM). Our results show that the species has a low marginality index, suggesting it is well adapted to the semiarid conditions of the study area. The main habitats used by E. isabellinus are water courses, scrublands, and zones with high primary productivity. The species avoids non–irrigated cropland and shows no preference for human settlements or irrigated cropland. This study provides information about the ecology of E. isabellinus in southeast Spain and allows us to discuss relevant aspects for its conservation.

Introduction: Huemul ( Hippocamelus bisulcus Molina) is the most threatened flag species of Southern Patagonia, where conservation efforts were not effective to avoid the retraction of its distribution area. Habitat quality modeling can assist to design better management strategies for regional conservation planning. The objective was to elaborate one habitat suitability map for huemul, defining the environmental characteristics at landscape level, and determining the distribution of the suitable habitat inside the current natural reserve network. Methods: We used a database of 453 records and explored 40 potential explanatory variables (climate, topographic, and landscape variables including human-related ones) to develop one habitat suitability map using the Environmental Niche Factor Analysis (ENFA) for Santa Cruz province (Argentina). We combined the outputs in a GIS project using different shapes, including the current natural reserve network. Results: We defined the potential habitat for huemul, where forest edges and ecotone zones (e.g., mainly alpine environments) were the most important environmental variables, as well as some forest types (e.g., Nothofagus pumilio). Habitat losses were found in the extreme potential distribution areas (northern and southern areas), probably related to the increasing ranch activities. The current natural reserve network maintains approximately half of the huemul potential habitat in Santa Cruz province, where National Parks presented the similar conservation importance than the Provincial natural reserves. Conclusions: Habitat suitability model for huemul can be used as a decision support system for new management strategies at different landscape levels to improve the current conservation efforts. [ABSTRACT FROM AUTHOR]

Modeling the distribution patterns of species is a generally efficient tool to assess their ecological characteristics. In this study, we compared ecological niche factor analysis (ENFA) and maximum entropy (Maxent) techniques to predict the most suitable distribution range of Rana macrocnemis. The Maxent model predicted potential suitable habitats for R. macrocnemis with high success rates (AUC Training data = 0.877 ± 0.039). According to the map constructed, three important variables had high contribution to species presence: temperature (50.4%), land cover (24.6%) and elevation (14.4%) variables. The ENFA results were relatively similar to Maxent jackknife analysis. The results implied that R. macrocnemis prefers grassland and needle leaf deciduous forest with high elevations, and low temperature. [ABSTRACT FROM AUTHOR]

Background: Numerous species, especially among rodents, are strongly affected by the availability of pulsed resources. The intermittent production of large seed crops in northern hemisphere tree species (e.g., beech Fagus spec.,oak Quercus spec., pine trees Pinus spec.) are prime examples of these resource pulses. Adult edible dormice are highly dependent on high energy seeds to maximize their reproductive output. For juvenile dormice the energy rich food is important to grow and fatten in a very short time period prior to hibernation. While these erratic, often large-scale synchronized mast events provide overabundant seed availability, a total lack of seed production can be observed in so-called mast failure years. We hypothesized that dormice either switch territories between mast and non-mast years, to maximize energy availability or select habitats in which alternative food sources are also available (e.g., fleshy fruits, cones). To analyze the habitat preferences of edible dormice we performed environmental niche factor analyses (ENFA) for 9 years of capture-recapture data. Results: As expected, the animals mainly used areas with high canopy closure and vertical stratification, probably to avoid predation. Surprisingly, we found that dormice avoided areas with high beech tree density, but in contrast preferred areas with a relatively high proportion of coniferous trees. Conifer cones and leaves can be an alternative food source for edible dormice and are less variable in availability. Conclusion: Therefore, we conclude that edible dormice try to avoid areas with large fluctuations in food availability to be able to survive years without mast in their territory. [ABSTRACT FROM AUTHOR]

The whip-like gorgonian Viminella flagellum (Alcyonacea, Ellisellidae) has an Atlantic-Mediterranean distribution. In Italian seas, the species is a common component of deep-sea rocky environments from the north-western Mediterranean area to the Strait of Sicily. V. flagellum grows in deep habitats, sometimes outlining the environment with dense forests. This work describes its habitat in an area in the southeastern Sardinian waters (central-western Mediterranean Sea), where a dense forest of the species was found. The specimens were filmed and photographed between 120 and 260 m depth with a Remotely Operated Vehicle (ROV). High-resolution multibeam echosounder (MBES) bathymetry data of the area were acquired and morphometric parameters were derived. These parameters were assumed to be relevant for the distribution of the whip-like gorgonians and were used in an Ecological Niche Factor Analysis (ENFA) to explore the niche and habitat preference of the target species. In order to identify which Eco-geographical variables are useful to predict coral distribution, we used the Maximum Entropy model (MaxEnt). Our results gave a first description of the habitat preference of V. flagellum . Specimens were found in a distinctive habitat, with respect to the overall features of the entire studied area which was characterised by a marked slope in a simple rocky seabed system, within a water depth range of 125–150 m. [ABSTRACT FROM AUTHOR]

Carnivores and their prey occurring at the extremes of their ecological niches face particular constraints in terms of habitat suitability (HS). We combined the use of camera traps and Ecological Niche Factor Analysis (ENFA) to calculate HS for jaguars (Panthera onca), pumas (Puma concolor), and 4 prey species (3-banded armadillos, Tolypeutes tricinctus; 9-banded armadillos, Dasypus novemcinctus; collared peccaries, Pecari tajacu; and gray brocket deer, Mazama gouazoubira) in Serra da Capivara National Park (SCNP), located in the semiarid Caatinga biome of Brazil. We also evaluated HS in relation to water management applied in the Park since 1994. Considering the physiological limitations of the Caatinga's species, we used an "edge of niche" habitat-suitability algorithm. For all species examined, distance to waterholes was the ecogeographical variable with the greatest contribution for the ENFA. Water management implemented in SCNP helps to ensure the persistence of predators and prey species, since the combination of topographic characteristics and location of waterholes explained most of HS for the analyzed species. [ABSTRACT FROM AUTHOR]

The development of species distribution models (SDMs) can help conservation efforts by generating potential distributions and identifying areas of high environmental suitability for protection. Our study presents a distribution and habitat map for lowland tapir in South America. We also describe the potential habitat suitability of various geographical regions and habitat loss, inside and outside of protected areas network. Two different SDM approaches, MAXENT and ENFA, produced relative different Habitat Suitability Maps for the lowland tapir. While MAXENT was efficient at identifying areas as suitable or unsuitable, it was less efficient (when compared to the results by ENFA) at identifying the gradient of habitat suitability. MAXENT is a more multifaceted technique that establishes more complex relationships between dependent and independent variables. Our results demonstrate that for at least one species, the lowland tapir, the use of a simple consensual approach (average of ENFA and MAXENT models outputs) better reflected its current distribution patterns. The Brazilian ecoregions have the highest habitat loss for the tapir. Cerrado and Atlantic Forest account for nearly half (48.19%) of the total area lost. The Amazon region contains the largest area under protection, and the most extensive remaining habitat for the tapir, but also showed high levels of habitat loss outside protected areas, which increases the importance of support for proper management.

It is difficult to map and quantify biodiversity at landscape level in areas with low data availability, despite demand from decision-makers. We propose a methodology to determine potential biodiversity pattern using habitat suitability maps of the understory plant species with highest cover and occurrence frequency in the three different forests types of Tierra del Fuego (Argentina). We used a database of vascular plants from 535 surveys from which we identified 35 indicative species. We explored more than 50 potential explanatory variables to develop habitat suitability maps of the indicative species, which were combined to develop a map of the potential biodiversity. Correlation among environmental, topographic and forest landscape variables were discussed, as well as the marginality and the specialization of the indicative species. We detected differences in the niches of the species prevailing in the three forest types. The developed map of potential biodiversity uncovered hotspots of biodiversity in the ecotone of Nothofagus pumilio and N. antarctica as well as in the wettest part of the mixed N. pumilio- N. betuloides forests. It allowed thus to identify forest areas with different conservation potential and can be readily used as a decision support system for conservation and management strategies at different scales including the identification of land-use conflicts (e.g. of biodiversity with timber production and livestock) and the development of a network of protected areas, which currently does not cover the forests of highest conservation value. [ABSTRACT FROM AUTHOR]

Availability and improved access to high-resolution digital terrain models (DTM) enables new approaches for the analysis of spatially explicit biological data. In this study, the spatial distribution of 16 tree species in a tropical mountain rain forest in South Ecuador and its relationship with topographic variables was evaluated at a fine-scale ecological level using two presence-only species distribution modelling techniques: The maximum entropy model (Maxent) and the ecological niche factor analysis (ENFA). Spatially explicit tree data stem from long-term forest monitoring plots in three microcatchments with a total area of 11.1 ha. Topographic variables were derived from a high-resolution DTM. Model performance was assessed by the true skill statistic (TSS) and area under curve (AUC) of the receiver operator characteristic (ROC), using both a k-fold approach and null-models. Performance varied among species and techniques, but generally Maxent models showed better performance than ENFA models. Furthermore, the ecological plausibility of the models was confirmed by comparing them with a previously established forest type classification. Among the explanatory topographic variables, elevation and a Topographic Position Index (TPI) appear as the main determinants for the distribution of most of the tree species. This study demonstrates that even on a small scale, the use of presence-only species distribution modelling techniques is a viable option for modelling suitable habitat for tree species in tropical mountain rain forests, indicating suitability for supporting stand-level planning and site-species matching techniques for natural forest management. [ABSTRACT FROM AUTHOR]

Habitat suitability models (HSMs) have so far been used mainly to study broad-scale patterns of species distribution based on environmental variables; however, they can also be applied to address conservation needs at finer scales. In this study, we evaluated the feasibility of using HSMs based on presence-only data to predict bat foraging habitat suitability around maternity roosts using radio-tracking location data. We radio-marked 34 Rhinolophus ferrumequinum and 29 Myotis emarginatus from two mixed-species maternity roosts (21.5 km apart) in a Mediterranean landscape. We generated foraging habitat suitability maps for the two species and the two colonies incorporating 17 land cover variables as well as distance from the maternity roosts. We then compared the performance of four presence-only models: Mahalanobis distance, ENFA, MADIFA and MaxEnt. Our study found that all four models generated foraging habitat suitability maps that performed well at predicting the species-specific quality of foraging habitat based on the configuration of the landscape. Riparian vegetation, woodland and distance from roosts play a key role in foraging habitat selection around colonies both for R. ferrumequinum and M. emarginatus. MaxEnt was the model that best predicted suitable foraging habitats. These are also the best models at predicting foraging habitat suitability with relatively good performance around another colony maternity roost using independent radio-tracking locations. Because many bat species are threatened by foraging habitat loss, habitat suitability modeling offers a useful tool in defining appropriate conservation guidelines that protect foraging habitats around bat maternity roosts. [ABSTRACT FROM AUTHOR]

During the last century, the global population of the Great Bustard (Otis tarda) has decreased and this species is now considered vulnerable. In Iran, the status of this species is much more critical and its distribution is limited to a few areas of Bukan county. We modeled the suitability of habitat for Great Bustards in Bukan County with the goal of determining the most important of distribution limiting factors of this valuable, rare and endangered bird in order to conservation and The map of effective factors including landform, land use, water resources and human factors was prepared using field data, previous available data, interpretation of satellite images, and their processing and analysis in GIS. To prepare the map of the variables, the circular, distance, and frequency analyses and for normalization of the maps, Box-Cox conversion were used. The model validation and the map classification of habitat suitability to desirable and undesirable classes were conducted using the Boyce index. The marginality factor (1.28) indicated that Otis tarda tends to live in marginal habitats. Low tolerability (0.1) and high specialization (9.2) scores also indicate that it is a special species within the county. According to our suitability map, only 6.5% (16000 ha) of the study area consists of desirable habitat. [ABSTRACT FROM AUTHOR]

In several European estuaries, the introduced Manila clam ( Ruditapes philippinarum ) has become a widespread and predominating species supplanting the native carpet shell clam ( Ruditapes decussatus ) whereas in other estuaries such as the Bay of Santander (Gulf of Biscay) this pattern has not been detected. Using this estuary as a case study, the potential coexistence/predominance patterns between these two species were explored with the objective of providing insight into the capacity of expansion of R. philippinarum . Firstly, the Ecological Niche Factor Analysis (ENFA) was applied to determine the niches of both species, using seven contemporary environmental variables, i.e. salinity, water depth, current velocity, and sediment sand, gravel, silt and organic matter content. Secondly, ENFA-derived habitat-suitability (HS) maps were simultaneously treated, using geospatial techniques and following HS index-based criteria, to determine the potential distribution patterns. Both species models performed well according to the cross-validation evaluation method. The environmental variables that most determined the presence of both clams were depth, current velocity and salinity. ENFA factors showed that R. philippinarum habitat differs more from the mean environmental conditions over the estuary (i.e. higher marginality) and has less narrow requirements (i.e. lower specialization). R. philippinarum dominated areas, determined by relatively lower current velocities and percentages of sand, higher organic matter contents and slightly shallower depths, were very reduced (i.e. 2.0% of the bay surface) compared to coexistence (47%) and R. decussatus predominance areas (7.4%). These results suggest that HS may regulate the expansion of R. philippinarum . ENFA, together with geospatial analysis of HS index, seems to be a valuable approach to explore the expansion potential of estuarine invasive or introduced species and thus support conservation decisions regarding native species. [ABSTRACT FROM AUTHOR]

Tanzania’s Ruaha landscape, centred around Ruaha National Park (RNP), is an international priority area for large carnivores, supporting >10% of the world’s lions ( Panthera leo ) and globally significant populations of leopards ( Panthera pardus ), spotted hyaenas ( Crocuta crocuta ) and other carnivores. However, Ruaha’s carnivore populations cause intense conflict with local people, mainly due to livestock depredation, and are exposed to alarming rates of retaliatory killing, especially on village land adjacent to RNP. Depredation risk is likely to be influenced by both habitat features and livestock husbandry, but the specific environmental risk factors, and relative importance of habitat and husbandry, have never been assessed in this landscape. Here, we assessed which ecogeographic variables (EGVs) were associated with depredation risk for grazing livestock on village land, and generated a predictive map of large carnivore predation risk, based on species distribution modelling algorithms (SDMs). Secondly, we investigated the relative influence of husbandry and EGVs on depredation risk of enclosed stock, based on a generalized linear model. Grazing livestock predation risk was higher closer to rivers, and in areas of lower elevation and low percentage of tree cover, with 41% of the area mapped as high-risk. For enclosed stock, predation risk was mostly influenced by low percentage of tree cover and increased rainfall, with no discernible influence of current husbandry, which suggests that traditional husbandry was insufficient to outweigh the innate predation risks associated with high-risk landscape areas. Adopting new husbandry methods, such as specialised guarding dogs and fortified livestock enclosures, could be valuable for reducing depredation and carnivore killing in the Ruaha landscape. [ABSTRACT FROM AUTHOR]

Many phocids are capital breeders, relying on stored reserves to sustain energetic requirements while on land. Their large body size, high energy expenditure during lactation, and the insulative effects of the blubber layer can lead to thermal stress from overheating, especially in warm and temperate climates. Thermal stress can influence fine-scale site choice on breeding colonies, and behavioral thermoregulation has been proposed as an explanation for the clear preferences shown by breeding female gray seals for proximity to pools of water. However, anecdotal observations suggest that pools of water may also be preferred for drinking, though water intake is difficult to verify without real-time physiological monitoring. Here, an alternative approach demonstrates that gray seals also require access to water for drinking. Using Ecological Niche Factor Analysis to examine fine-scale physical determinants of pupping site choice at North Rona, Scotland, we found that lactating mothers showed preference for lower salinity pools. This is most pronounced early in the season, when ambient temperatures and presumably thermal stress are greatest. Given that the cooling effect of fresh and salt water should be equivalent, the most parsimonious explanation for this preference for fresh water pools is that lactating females use these pools for drinking. [ABSTRACT FROM AUTHOR]

Using data on the known Iberian distributions of 10 species of Lepidoptera listed in the Habitats Directive referenced to the 10 × 10 km UTM grid, we determined their potential distributions and their relationships with selected bioclimatic factors associated with mean temperature and precipitation using Ecological Niche Factor Analysis (ENFA). Scores for Specialization and Marginality were determined in order to evaluate the relationships between the predictions of the model and climatic factors. The number of squares on the Iberian Peninsula in which the species are recorded and those squares predicted to be favourable for these species were determined if they matched the network of Protected Natural Areas. This suggested that a further eight 10 × 10 km squares should be included in Protected Natural Areas. The results also indicate that climate determines the distributions of most of the species. Although overall there is a close association between the observed and predicted distributions, the less thoroughly documented geographic ranges (i.e. those of the moth species) depart from this pattern. [ABSTRACT FROM AUTHOR]

Abstract: The gold coral Savalia savaglia (Cnidaria, Zoantharia) is a rare component of the mesophotic zone of the Mediterranean Sea and northeastern Atlantic Ocean. During two field campaigns along the Italian coast in the South Tyrrhenian Sea, two populations of this species were discovered. The specimens were filmed and photographed by means of a Remotely Operated Vehicle (ROV). To identify the role of local bathymetry and other derived variables on presence and distribution of S. savaglia we used a Habitat Suitability (HS) modeling technique based on Ecological Niche Factor Analysis (ENFA), utilizing high-resolution multibeam bathymetry and ROV data. Among the set of environmental variables derived from multibeam data, slope, rugosity, eastness and distance to rocks, appear to be the main variables involved in S. savaglia distribution, pointing out that the habitat differs considerably from the mean environmental conditions over the study area, and that S. savaglia ecological niche is significantly narrower than the available habitat. The HS map was developed to differentiate the sea floor into suitability classes. The comparison between suitability classes and presence data showed that the HS map is coherent with the observed spatial distribution of the species. The most suitable habitat for S. savaglia is characterized by a rough sea floor with rocks that is steeply sloped, oriented northeast, and within a water depth range of 34–77m. Our study suggests that predictive modeling is an approach that can be applied to other deep coral species to locate areas with a suitable habitat. Considering the difficulties to reach the habitats in which these species live, this approach could be essential to planning further studies that help define areas where the species may be present. [Copyright &y& Elsevier]

Increasing attempts are made to understand the factors responsible for both the demographic and genetic depletion in amphibian populations. Landscape genetics aims at a spatially explicit correlation of genetic population parameters to landscape features. Using data from the endangered fire-bellied toad Bombina bombina in Brandenburg (Northeastern Germany), we performed an environmental niche factor analysis (ENFA), relating demographic (abundance) and genetic (diversity at 17 microsatellite loci and partial sequences of the mitochondrial control region in 434 individuals from 16 populations) parameters to ecological and anthropogenic variables such as temperature, precipitation, soil wetness, water runoff, vegetation density, and road/traffic impact. We found significant correlations between road disturbance and observed heterozygosity and between soil wetness and mitochondrial diversity. As the influences of the environmental variables can differ between different indicators for genetic diversity, population size and abundance data, our ENFA-based landscape genetics approach allows us to put various aspects of long- versus short term effective population size and genetic connectivity into an ecological and spatially explicit context, enabling potentially even forecast assessment under future environmental scenarios. [ABSTRACT FROM AUTHOR]