Changes In Habitat Suitability Research Articles

Improve the roles of nature reserves in conservation of endangered pheasant in a highly urbanized region

Nature reserves play an extraordinarily important role in conserving animal populations and their habitats. However, landscape change and unreasonable zoning designations often render these protected areas inadequate. Therefore, regular evaluation of the efficacy of protected lands is critical for maintaining and improving management strategies. Using species distribution models and GAP analysis, we assessed the changes in suitable habitat for the Brown Eared-pheasant (Crossoptilon mantchuricum) in two Chinese nature reserves between 1995 and 2013. Our results showed that the habitat suitability of Brown Eared-pheasant has changed dramatically during this period, and fragmentation analyses showed an increase in concentration area and decrease in patch area. In particular, our findings show that the national nature reserves need to adjust their ranges to ensure the conservation of this flagship species. Our study further provides a new viewpoint for evaluating the efficacy of protected lands, particularly in highly urbanized regions where conservation goals must be balanced with changing landscapes.

Using fire to enhance rewilding when agricultural policies fail

Rewilding has been proposed as an opportunity for biodiversity conservation in abandoned landscapes. However, rewilding is challenged by the increasing fire risk associated with more flammable landscapes, and the loss of open-habitat specialist species. Contrastingly, supporting High Nature Value farmlands (HNVf) has been also highlighted as a valuable option, but the effective implementation of agricultural policies often fails leading to uncertain scenarios wherein the effects of wildfire management remain largely unexplored. Herein, we simulated fire-landscape dynamics to evaluate how fire suppression scenarios affect fire regime and biodiversity (102 species of vertebrates) under rewilding and HNVf policies in the future (2050), in a transnational biosphere reserve (Gerês-Xurés Mountains, Portugal-Spain). Rewilding and HNVf scenarios were modulated by three different levels of fire suppression effectiveness. Then, we quantified scenario effects on fire regime (burned and suppressed areas) and biodiversity (habitat suitability change for 2050). Simulations confirm HNVf as a long-term opportunity for fire suppression (up to 30,000 ha of additional suppressed areas between 2031 and 2050 in comparison to rewilding scenario) and for conservation (benefiting around 60% of species). Rewilding benefits some species (20%), including critically endangered, vulnerable and endemic taxa, while several species (33%) also profit from open habitats created by fire. Although HNVf remains the best scenario, rewilding reinforced by low fire suppression management may provide a nature-based solution when societal support through agricultural policies fails.

Population genetic structure and demographic history of the lone star tick, Amblyomma americanum (Ixodida: Ixodidae): New evidence supporting old records.

Range expansions are a potential outcome of changes in habitat suitability, which commonly result as a consequence of climate change. Hypotheses on such changes in the geographic distribution of a certain species can be evaluated using population genetic structure and demography. In this study we explore the population genetic structure, genetic variability, demographic history of, and habitat suitability for Amblyomma americanum, a North American tick species that is a known vector of several pathogenic microorganisms. We used a double digestion restriction site-associated DNA sequencing technique (dd-RAD seq) and discovered 8,181 independent single nucleotide polymorphisms (SNPs) in 189 ticks from across the geographic range of the species. Genetic diversity was low, particularly when considering the broad geographic range of this species. The edge populations were less diverse than populations belonging to the historic range, possibly indicative of a range expansion, but this hypothesis was not statistically supported by a test based on genetic data. Nonetheless, moderate levels of population structure and substructure were detected between geographic regions. For New England, demographic and species distribution models support a scenario where A.americanum was present in more northern locations in the past, underwent a bottleneck, and subsequently recovered. These results are consistent with a hypothesis that this species is re-establishing in this area, rather than one focused on range expansion from the south. This hypothesis is consistent with old records describing the presence of A.americanum in the northeastern US in the early colonial period.

Modeling the interactive effects of nutrient loads, meteorology, and invasive mussels on suitable habitat for Bighead and Silver Carp in Lake Michigan

Anthropogenic stressors that affect ecological processes in the Laurentian Great Lakes can impact their susceptibility to bioinvasions. Bighead Hypophthalmichthys nobilis and Silver Carp H. molitrix, collectively ‘bigheaded carps’ (BHC), are planktivorous fishes threatening to invade Lake Michigan. While previous studies indicate the lake contains habitat suitable for BHC growth, there is a need to understand how anthropogenic-driven changes to the abiotic and biotic environment could alter its vulnerability to BHC. We applied a spatially explicit model of BHC growth rate potential (GRP; g g−1 d−1) to nine biophysical model scenarios to evaluate changes in habitat suitability in Lake Michigan. Scenarios differed in meteorology (cool, reference, warm), annual tributary phosphorus loads (0, 3300, and 5600 MTA), and the presence/absence of invasive dreissenid mussels. Mussel effects on BHC GRP relied on their contact with the surface mixed layer (SML), the depth of which was affected by meteorology. The warm year advanced the expansion of Bighead Carp habitat by increasing temperature-dependent foraging rates and lessening the time of competitive interaction with mussels due to earlier stratification separating mussels from the SML. Phosphorus loads were the most influential driver of the lake’s suitability. Compared to present conditions, we estimate BHC could have grown an additional 8–40% annually in the 1980s when mussels were not in the lake and phosphorus loads were higher. Our study demonstrates how climate change and nutrient enrichment can increase Lake Michigan’s vulnerability to BHC by affecting thermal regime and productivity, thereby limiting negative effects of dreissenid mussels on BHC growth.

Clearing up the Crystal Ball: Understanding Uncertainty in Future Climate Suitability Projections for Amphibians

Amphibian populations are threatened globally, and one of the hypotheses for these declines is climate change. Species distribution models are frequently used to predict changes in suitable habitat as a result of changing climates; however, these projections can be heavily influenced by choice of modeling approach. To evaluate global predictions for amphibians, we conducted a literature review of studies that utilize correlative species distribution models to project changes in climate suitability under various climate change scenarios. We paid particular attention to the use of model selection in choosing among candidate species distribution models (SDMs) so as to control for overparameterization of SDMs. In addition, we conducted a case study with three species of Slender Salamanders (Batrachoseps) to further investigate the impact of differences in modeling decisions on projected amphibian climate suitability. We found 83 studies (including the present case study) in which projections of future climate suitability were made for amphibian species. Of those studies, 36 included estimates of percent change in climate suitability and thus were included in our meta-analysis. These studies included projections for over 1000 species or species complexes, with the majority being Anurans (86%), and encompassed five continents with the most representation in South America, Europe, and North America. Across these studies, average projected change in climate suitability ranged from －70% to 167%, and these projected changes varied with dispersal assumptions representative concentration pathway (RCP) used, the projection year, and taxonomic order. Only three of the 36 studies reported the use of Akaike information criterion (AIC)-based model selection to choose a best-fit SDM. However, our case study demonstrated that predicted change in climate suitability varied whether the best-fit or default SDM was used for projections. Further, this result varied among species (ΔAIC = 0), suggesting that the impact of overparameterization differs across species. Our results illustrate that there is a pressing need to project climate suitability across more species and more geographic regions. In addition, we may need to revisit projections for previously investigated species to evaluate additional climate scenarios and whether overparameterization may have influenced projections. Our ability to accurately model future changes in climate suitability will be essential for successful conservation and management plans for amphibians.

Factors influencing initial population establishment and habitat expansion of introduced nutrias (Myocastor coypus) in South Korea

Biological invasions have increased in recent years, as these are facilitated by traffic networks of human infrastructure. Accidental release from the animal industry is an important cause of biological invasions, and allows for the clear determination of the source of non-native species. Such examples of invasion can be beneficial for studies on the relative importance of local environments by comparing establishment successes from different sources. Nutrias (Myocastor coypus), originally introduced to South Korea for meat and fur production, escaped from local farms into the wild in the late 1990s. Using ensemble species distribution models (ESDM), we assessed 1) suitable habitat conditions for nutrias, 2) establishment success from different source localities after the nutrias' escape from farms, and 3) changes in habitat suitability based on regional climate scenarios. We found that the distribution of nutrias was largely influenced by temperature regime (i.e., minimum temperature during the winter; 44.1 ± 11.4% of variable contribution in the ESDM) and invasion success of nutrias that had escaped from different local farms was also related to the local climate conditions. Escaped nutrias were widely observed around the farms with favorable habitat conditions. Our model predicted a gradual expansion of habitats suitable for nutrias; however, core habitats are isolated by high-mountain ridges and watershed boundaries. National campaigns to prevent translocation between different watersheds are important to control further expansion of escaped nutrias.

The changes in suitable habitats for 114 endemic bird species in China during climate warming will depend on the probability

Quantifying the uncertainty and risk of reducing distribution ranges of the birds in a shifting climate is crucial regarding decision-making on the adaptation of biodiversity to climate warming. By using the representative concentration pathway scenarios of changing climate, fuzzy set classifications, and Monte Carlo techniques, an investigation of the uncertainty and risk of shifting ranges for 114 endemic birds in China from climate change was conducted. In response to non-stochastic changing climate conditions, the abundance of 114 species would increase in some locations of western and northeastern China and would decline in some sites of southeastern, eastern, northern, and central China; approximately 40–60 species would lose less than 20% or 20–40% of their current suitable areas, and about 110 species would exhibit distributions covering more than 80% of their total ranges. For stochastic changing climate scenarios, the number of the birds that lost distinct extents of the suitable ranges decreased with enhancing the likelihood; with a probability of beyond 0.6, the number of the birds that lost less than 20%, 20–40%, 40–60%, 60–80%, and greater than 80% of their present ranges was approximately 13–20, 10–22, 1–8, 1–3, and 5–8, respectively, and the number of the birds that inhabited less than 20%, 20–40%, 40–60%, 60–80%, and over 80% of their all suitable ranges was approximately 7–10, 15–25, 6–11, 1–4, and 26–30, respectively. Approximately 36 species of 114 endemic bird species will be posed extinction risk by climate warming if without any adaptation measures.

An ensemble high‐resolution projection of changes in the future habitat of American lobster and sea scallop in the Northeast US continental shelf

AbstractAimTo address the uncertainty associated with climate‐driven biogeographical changes in commercial fisheries species through an ensemble species distribution modelling (SDM) approach.LocationNortheast US Continental Shelf Large Marine Ecosystem (NEUS‐LME).MethodsWe combined an ensemble SDM platform (BIOMOD 2) and a high‐resolution global climate model (NOAA GFDL CM2.6) to quantify spatiotemporal changes in habitat of two commercially important species in the Northeast US Continental Shelf Large Marine Ecosystem (NEUS‐LME); American lobster (Homarus americanus); and sea scallop (Placopecten magellanicus). An ensemble SDM was calibrated using multi‐decadal fisheries‐independent surveys (1984–2016). Statistically weighted species‐specific ensemble SDM outputs were combined with 80 years of projected bottom temperature and salinity changes in response to a high greenhouse gas emissions scenario (an annual 1% increase in atmospheric CO2).ResultsStatistically significant changes (p < .05) in habitat suitability for both species were found over a large portion of the study area. Sea scallop undergoes a northward shift over the study period, while American lobster moves further offshore. The ensemble projections showed that several management zones were identified with increases and decreases in species‐specific habitat. Uncertainty due to variations in ensemble member models was also found in the direction of change within each management zone.Main conclusionsThis study provides ensemble estimates of climate‐driven changes and associated uncertainties in the biogeography of two economically important species in the United States. Projected climate change in the NEUS‐LME will pose management challenges, and our ensemble projections provide useful information for climate‐ready management of commercial fisheries.

Changes in habitat suitability over a two decade period before and after Asian elephant recolonization

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.

The effect of scale in quantifying fire impacts on species habitats

BackgroundFire size and severity have increased in the western United States in recent decades, and are expected to continue to increase with warming climate. Habitats for many species are threatened by large and high-severity fires, but the effect of spatial scale on the relationship between fires and habitat modifications is poorly understood. We used the 2011 Wallow Fire—the largest wildfire in the state history of Arizona, USA—as a case study and assessed changes in predicted nesting habitat of the threatened Mexican spotted owl (Strix occidentalis Xántus de Vésey) in the first three years following the fire. Our objective was to explore potential relationships between burn severity and changes in habitat suitability at different spatial scales. To accomplish this, we applied a multi-scale optimized habitat selection model to pre- and post-fire landscapes and compared the differences in predictions along a continuous scale gradient.ResultsFire effects on habitat quality were spatially variable and the strength and direction of relationships were scale-dependent. Spatial patterns of burn-severity mosaic resembled the patterns of habitat suitability change. High burn severity reduced nesting habitat suitability and this relationship was strongest at broad scales. Pre-fire habitat suitability was positively related to burn severity, again at fairly broad scales, but the relationship was weak. Low-severity fires had little effect on habitat suitability.ConclusionsMulti-scale analysis may influence the statistical measures of goodness of fit in assessing fire effects on species and their habitats. Future studies should explicitly address spatial scale when quantifying fire effects.

Challenges and Opportunities for Terrapene carolina carolina Under Different Climate Scenarios

An unprecedented rate of global climate change as a result of human impacts has affected both endotherms and ectotherms. This is of special concern for ectotherms, such as reptiles, as these species are suffering from large population declines and lack the dispersal ability of other taxa. There are many protected areas across the United States; however, these areas are fragmented, which hinders dispersal. We examined species distribution and dispersal capabilities for Terrapene carolina carolina, a relatively narrow range, low dispersal, and vulnerable species. We created climatic suitability models to predict changes in suitable habitat and identified important predictor variables. We modeled three time periods using MaxEnt and hypothesized that there would be an increase in northern habitat. We found that most of the suitable habitat changed at the northern end of the range and that mean temperature of driest quarter had the most influence on future predictions. Overall there were relatively moderate changes in suitable habitat, but where these changes occur affects accessibility. As an example, we examined these local scale movements within Oak Openings Region and found that individuals are capable of dispersing to new suitable habitats; however, other physical barriers will hinder movements. In conclusion, there is a critical need to protect this vulnerable reptilian species and our results suggest that T. c. carolina will expand their distribution northward. We suggest that land managers increase connectivity among protected areas to facilitate dispersal, but future studies should incorporate other dynamic ecological factors at finer spatial scale.

Evaporative water loss simulation improves models' prediction of habitat suitability for a high-elevation forest skink.

Accurate evaluation of habitat availability for wildlife is relevant for ecological applications. Researchers have frequently used models to simulate habitats thermally suitable for reptiles, but these results have limited application for species highly selective for habitat humidity. Here, we use the biophysical Niche Mapper™ model to investigate impacts of vegetation cover on the habitat quality of a high-elevation forest skink, Sphenomorphus taiwanensis, and to predict changes in habitat suitability in a future warmer climate (3°C increase in air temperature). We assess habitat suitability with different densities of canopy cover in our study areas using two ecologically relevant estimates for lizards: maximum activity time and evaporative water loss (EWL) during the activity season. We measured preferred body temperature and EWL of this species for model parameterization, and behavioral response to EWL to supplement habitat quality assessment. The results indicated that this species is sensitive to EWL and reduces its activity when dehydrated. The model predicted that denser canopy levels increase microclimate cooling and humidity, and that most canopy levels are thermally suitable for this species, as the lizard can thermoregulate to manage adverse temperatures. Nevertheless, increasing canopy density could significantly decrease EWL during activity. In the warmer climate scenario, simulated maximum activity time and EWL changed little because of thermoregulation behavior. Our results suggest that habitat preference of this species is a consequence of water and energy requirements, and we note that combining EWL and maximum activity time data can enhance model accuracy of lizards' habitat quality in a warmer climate.

Importance of spatio–temporal connectivity to maintain species experiencing range shifts

Climate change can affect the habitat resources available to species by changing habitat quantity, suitability and spatial configuration, which largely determine population persistence in the landscape. In this context, dispersal is a central process for species to track their niche. Assessments of the amount of reachable habitat (ARH) using static snap‐shots do not account, however, for the temporal overlap of habitat patches that may enhance stepping‐stone effects. Here, we quantified the impacts of climate change on the ARH using a spatio–temporal connectivity model. We first explored the importance of spatio–temporal connectivity relative to purely spatial connectivity in a changing climate by generating virtual species distributions and analyzed the relative effects of changes in habitat quantity, suitability and configuration. Then, we studied the importance of spatio–temporal connectivity in three vertebrate species with divergent responses to climate change in North America (grey wolf, Canadian lynx and white‐tailed deer). We found that the spatio–temporal connectivity could enhance the stepping‐stone effect for species predicted to experience range contractions, and the relative importance of the spatio–temporal connectivity increased with the reduction in habitat quantity and suitability. Conversely, for species that are likely to expand their ranges, spatio–temporal connectivity had no additional contribution to improve the ARH. We also found that changes in habitat amount (quantity and suitability) were more influential than changes in habitat configuration in determining the relative importance of spatio–temporal connectivity. We conclude that spatio–temporal connectivity may provide less biased and more realistic estimates of habitat connectivity than purely spatial connectivity.

Climate change and the potential expansion of buffelgrass (Cenchrus ciliaris L., Poaceae) in biotic communities of Southwest United States and northern Mexico

In the last decades, more than six hundred exotic species have become established throughout the region of the southwestern United States and northwestern Mexico, including the African buffelgrass (Cenchrus ciliaris L.). Buffelgrass often causes negative impacts on natural ecosystems and it is considered a highly invasive species in many parts of the world. We used 18,550 records from 260 datasets and species distribution modeling (SDM) to provide support for the climatically based and topographic hypotheses, which claim that current climate and topography affect species distribution patterns of plants. We also investigated (1) the geographical distribution of habitat suitability across biotic communities of the Southwest United States and northern Mexico, (2) the association between habitat suitability, climate variables and topography, and (3) the potential effects of climate change on the future distribution of buffelgrass. We found that the geographic pattern of suitability in the southwest generally increases west- and southward, with some high suitability areas also occurring in southern areas of Arizona, USA, and across the state of Sonora, Mexico. We observed that mean temperature and annual precipitation explain spatial variation in suitability better than other climatic and non-climatic variables. Climate change models indicated significant opportunities for contraction across the buffelgrass’ range and fewer for range expansion. In all scenarios, SDMs predicted a high contraction of suitable habitat. Most of these contractions would occur in portions of the Sonoran Desert and the foothills of the Sierra Madre Occidental. We show, for the first time, the potential changes in buffelgrass habitat suitability across major biomes of the Southwest region, under future climate change scenarios.

Changes in streamflow and water temperature affect fish habitat in the Athabasca River basin in the context of climate change

Changes to natural flow and air temperature in the context of climate change can have impacts on physiology, distribution and survival of fish. Of particular interest is the Athabasca River basin, a highly biologically productive basin that includes one of the largest boreal freshwater inland river deltas in the world and serves as habitat for many fish species. Earlier melt events, higher winter and spring flows and lower summer flows are expected as a consequence of climate change in this basin. Here, we model changes in river flow and water temperature under changing climate scenarios through the integration of a physically-based semi-distributed hydrological model and a 1D stream water temperature model forced by climate change scenarios. The modeled changes in streamflow and water temperature are used to predict changes in habitat suitability for the Athabasca Rainbow Trout (ART) (Oncorhynchus mykiss), a unique ecotype of trout considered as a ‘species at risk’. The results indicate that future flow decreases in most of the basin can lead to reduced flow velocities and water depths making current ART habitat suboptimal. Also, warming low-land habitats and increasing water temperatures will increase metabolic rates and stress fish forcing them to migrate upstream to cooler waters confining their habitat range.

Dispersal and local persistence shape the genetic structure of a widespread Neotropical plant species with a patchy distribution.

Isolated populations constitute an ideal laboratory to study the consequences of intraspecific divergence, because intrinsic incompatibilities are more likely to accumulate under reduced gene flow. Here, we use a widespread bromeliad with a patchy distribution, Pitcairnia lanuginosa, as a model to infer processes driving Neotropical diversification and, thus, to improve our understanding of the origin and evolutionary dynamics of biodiversity in this highly speciose region. We assessed the timing of lineage divergence, genetic structural patterns and historical demography of P. lanuginosa, based on microsatellites, and plastid and nuclear sequence data sets using coalescent analyses and an Approximate Bayesian Computation framework. Additionally, we used species distribution models (SDMs) to independently estimate potential changes in habitat suitability. Despite morphological uniformity, plastid and nuclear DNA data revealed two distinct P. lanuginosa lineages that probably diverged through dispersal from the Cerrado to the Central Andean Yungas, following the final uplift of the Andes, and passed through long-term isolation with no evidence of migration. Microsatellite data indicate low genetic diversity and high levels of inbreeding within populations, and restricted gene flow among populations, which are likely to be a consequence of bottlenecks (or founder events), and high selfing rates promoting population persistence in isolation. SDMs showed a slight expansion of the suitable range for P. lanuginosa lineages during the Last Glacial Maximum, although molecular data revealed a signature of older divergence. Pleistocene climatic oscillations thus seem to have played only a minor role in the diversification of P. lanuginosa, which probably persisted through adverse conditions in riparian forests. Our results imply drift as a major force shaping the evolution of P. lanuginosa, and suggest that dispersal events have a prominent role in connecting Neotropical open and forest biomes.

The trade-off between tidal-turbine array yield and environmental impact: A habitat suitability modelling approach

In the drive towards a carbon-free society, tidal energy has the potential to become a valuable part of the UK energy supply. Developments are subject to intense scrutiny, and potential environmental impacts must be assessed. Unfortunately many of these impacts are still poorly understood, including the implications that come with altering the hydrodynamics. Here, methods are proposed to quantify ecological impact and to incorporate its minimisation into the array design process. Four tidal developments in the Pentland Firth are modelled with the array optimisation tool OpenTidalFarm, that designs arrays to generate the maximum possible profit. Maximum entropy modelling is used to create habitat suitability maps for species that respond to changes in bed-shear stress. Changes in habitat suitability caused by an altered tidal regime are assessed. OpenTidalFarm is adapted to simultaneously optimise array design to maximise both this habitat suitability and to maximise the profit of the array. The problem is thus posed as a multi-objective optimisation problem, and a set of Pareto solutions found, allowing trade-offs between these two objectives to be identified. The methods proposed generate array designs that have reduced negative impact, or even positive impact, on the habitat suitability of specific species or habitats of interest.

Predicting seasonal occurrence of leatherback turtles (Dermochelys coriacea) in eastern Canadian waters from turtle and ocean sunfish (Mola mola) sighting data and habitat characteristics

Part of the western Atlantic population of leatherback turtles (Dermochelys coriacea (Vandelli, 1761)) forage in Canadian waters, where high-use areas have been identified using satellite telemetry and opportunistic sightings. Here, we use sightings of leatherback turtles and ocean sunfish (Mola mola (Linnaeus, 1758)) obtained during a systematic large-scale aerial survey, along with opportunistic turtle sightings, to examine the seasonal occurrence and distribution of leatherback turtles in eastern Canada. Using environmental correlates, we predict the spatial and seasonal development of potentially suitable habitats. All data sets confirmed the presence of leatherback turtles off Nova Scotia during summer. They also highlighted turtle occurrence off southern Newfoundland. Opportunistic sightings suggest a seasonal shift in main turtle concentrations from southwest to northeast, with use of southern Newfoundland waters extending into September. A generalized additive model linking environmental characteristics and turtle observations suggests adding the Grand Banks off Newfoundland and waters east of Anticosti Island in the Gulf of St. Lawrence to the potentially important habitat for leatherback turtles. Direct observations helped delineate habitat currently used by leatherback turtles. In the context of climate change, this modelling approach may improve our ability to forecast changes in turtle habitat suitability and the risks of entrapment or collision associated with potentially changing usage patterns.

Spatiotemporal dynamics in habitat suitability of a large Arctic herbivore: Environmental heterogeneity is key to a sedentary lifestyle

Quantifying spatial and temporal variation in habitat suitability is crucial to understand changes in animal distribution and to inform conservation and management initiatives, especially for species occupying regions profoundly impacted by climatic and environmental change. A detailed understanding of the environmental conditions shaping seasonal habitat suitability of free-ranging muskoxen (Ovibos moschatus), a key species in the Arctic tundra ecosystem, is currently lacking. We applied the maximum entropy modelling algorithm (MaxEnt) to build seasonal species distribution models (SDMs) over four years to quantify variation in habitat suitability in time and space. Suitable habitat was predicted based on location data from 27 GPS-collared adult female muskoxen in northeast Greenland and the spatial distribution of topographic variables and landcover within the study area. Overall, our results highlight distinct seasonal differences in both the spatial extent and distribution of suitable muskox habitat. Suitable space was smallest and spatially most clustered during autumn, and increased in extent and dispersion throughout the snow-covered period until peaking in summer. Nonetheless, the importance of environmental variables influencing habitat suitability was consistent across inter-annual and seasonal scales as habitat suitability was consistently predicted to be highest in vegetated, flat to moderately rugged terrain at low to medium elevation (<500–600 m.a.s.l.) close to the coast (<5–10 km). One year with extraordinary large amounts of snow differed from the general pattern, exhibiting markedly smaller areas of suitable habitat and higher spatial clustering. The results support the notion that adult female muskoxen are able to lead a relatively sedentary lifestyle due to the close proximity of suitable habitats across all seasons. However, above-average snow depths appear to be a potential bottleneck limiting access to suitable habitat, with consequences even beyond the snow-covered season. Our study provides the foundation for assessing potential future changes in habitat suitability and distribution of this key Arctic herbivore.

Phylogeography, population genetics and distribution modelling reveal vulnerability of Scirpus longii (Cyperaceae) and the Atlantic Coastal Plain Flora to climate change.

A proactive approach to conservation must be predictive, anticipating how habitats will change and which species are likely to decline or prosper. We use composite species distribution modelling to identify suitable habitats for 18 members of the North American Atlantic Coastal Plain Flora (ACPF) since the Last Glacial Maximum and project these into the future. We then use Scirpus longii (Cyperaceae), a globally imperiled ACPF sedge with many of the characteristics of extinction vulnerability, as a case study. We integrate phylogeographical and population genetic analyses and species distribution modelling to develop a broad view of its current condition and prognosis for conservation. We use genotyping-by-sequencing to characterize the genomes of 142 S.longii individuals from 20 populations distributed throughout its range (New Jersey to Nova Scotia). We measure the distribution of genetic diversity in the species and reconstruct its phylogeographical history using the snapp and rase models. Extant populations of S.longii originated from a single refugium south of the Laurentide ice sheet around 25ka. The genetic diversity of S.longii is exceedingly low, populations exhibit little genetic structure and the species is slightly inbred. Projected climate scenarios indicate that nearly half of extant populations of S.longii will be exposed to unsuitable climate by 2070. Similar changes in suitable habitat will occur for many other northern ACPF species-centres of diversity will shift northward and Nova Scotia may become the last refuges for those species not extinguished.