scholarly journals Modeling Distribution and Habitat Suitability for the Snow Leopard in Bhutan

2021 ◽  
Vol 2 ◽  
Author(s):  
Dechen Lham ◽  
Gabriele Cozzi ◽  
Stefan Sommer ◽  
Phuntsho Thinley ◽  
Namgay Wangchuk ◽  
...  
Keyword(s):  
Protected Areas ◽  
Species Distribution ◽  
Habitat Suitability ◽  
Anthropogenic Factors ◽  
Suitable Habitat ◽  
Snow Leopard ◽  
Potential Contribution ◽  
Ensemble Model ◽  
Model Framework ◽  
Biological Corridors

The snow leopard (Panthera uncia) is one of the world's most elusive felids. In Bhutan, which is one of the 12 countries where the species still persists, reliable information on its distribution and habitat suitability is lacking, thus impeding effective conservation planning for the species. To fill this knowledge gap, we created a country-wide species distribution model using “presence-only” data from 420 snow leopard occurrences (345 from a sign survey and 77 from a camera-trapping survey) and 12 environmental covariates consisting of biophysical and anthropogenic factors. We analyzed the data in an ensemble model framework which combines the outputs from several species distribution models. To assess the adequacy of Bhutan's network of protected areas and their potential contribution toward the conservation of the species, we overlaid the output of the ensemble model on the spatial layers of protected areas and biological corridors. The ensemble model identified 7,206 km2 of Bhutan as suitable for the snow leopard: 3,647 km2 as highly suitable, 2,681 km2 as moderately suitable, and 878 km2 as marginally suitable. Forty percent of the total suitable habitat consisted of protected areas and a further 8% of biological corridors. These suitable habitats were characterized by a mean livestock density of 1.3 individuals per hectare, and a mean slope of 25°; they closely match the distribution of the snow leopard's main wild prey, the bharal (Pseudois nayaur). Our study shows that Bhutan's northern protected areas are a centre for snow leopard conservation both at the national and regional scale.

scholarly journals The benefits of using topographic features to predict climate-resilient habitat for migratory forest landbirds: An example for the Rusty Blackbird, Olive-sided Flycatcher, and Canada Warbler

The Condor ◽  
2020 ◽  
Vol 122 (1) ◽  
Author(s):  
Shannon Bale ◽  
Karen F Beazley ◽  
Alana Westwood ◽  
Peter Bush
Keyword(s):  
Nova Scotia ◽  
Species Distribution ◽  
Habitat Suitability ◽  
Strong Association ◽  
Breeding Habitat ◽  
Important Predictor ◽  
Suitable Habitat ◽  
Topographic Features ◽  
Precipitation Regimes ◽  
Rusty Blackbird

Abstract Maintaining a functionally connected network of high-quality habitat is one of the most effective responses to biodiversity loss. However, the spatial distribution of suitable habitat may shift over time in response to climate change. Taxa such as migratory forest landbirds are already undergoing climate-driven range shifts. Therefore, patches of climate-resilient habitat (also known as “climate refugia”) are especially valuable from a conservation perspective. Here, we performed maximum entropy (Maxent) species distribution modeling to predict suitable and potentially climate-resilient habitat in Nova Scotia, Canada, for 3 migratory forest landbirds: Rusty Blackbird (Euphagus carolinus), Olive-sided Flycatcher (Contopus cooperi), and Canada Warbler (Cardellina canadensis). We used a reverse stepwise elimination technique to identify covariates that influence habitat suitability for the target species at broad scales, including abiotic (topographic control of moisture and nutrient accumulation) and biotic (forest characteristics) covariates. As topography should be relatively unaffected by a changing climate and helps regulate the structure and composition of forest habitat, we posit that the inclusion of appropriate topographic features may support the identification of climate-resilient habitat. Of all covariates, depth to water table was the most important predictor of relative habitat suitability for the Rusty Blackbird and Canada Warbler, with both species showing a strong association with wet areas. Mean canopy height was the most important predictor for the Olive-sided Flycatcher, whereby the species was associated with taller trees. Our models, which comprise the finest-scale species distribution models available for these species in this region, further indicated that, for all species, habitat (1) remains relatively abundant and well distributed in Nova Scotia and (2) is often located in wet lowlands (a climate-resilient topographic landform). These findings suggest that opportunities remain to conserve breeding habitat for these species despite changing temperature and precipitation regimes.

scholarly journals Environmental requirements for three sea pen species: relevance to distribution and conservation

2014 ◽  
Vol 72 (2) ◽  
pp. 576-586 ◽  
Author(s):  
C. Greathead ◽  
J. M. González-Irusta ◽  
J. Clarke ◽  
P. Boulcott ◽  
L. Blackadder ◽  
...  
Keyword(s):  
Protected Areas ◽  
Marine Protected Areas ◽  
Habitat Suitability ◽  
Environmental Variables ◽  
Suitable Habitat ◽  
Habitat Suitability Index ◽  
Suitability Index ◽  
Environmental Requirements ◽  
Adequacy Criterion ◽  
Suitable Area

Abstract The aim is to determine the environmental requirements, estimate the extent of suitable habitat for three sea pen species, and assess the implications for marine protected areas (MPAs). The sea pen Funiculina quadrangularis and the habitat associated with two further sea pen species, Virgularia mirabilis and Pennatula phosphorea, are of key conservation importance and are recommended for protection within MPAs. This study models their potential distributions using the MAXimum ENTropy algorithm and assesses these in relation to five possible marine protected areas (pMPAs) proposed for Scottish waters. Metrics relevant to assessing the efficacy of MPAs are also presented. Four environmental variables of prime importance for predicting the presence of all three species of sea pen were identified: mud, minimum salinity, depth, and gravel. The habitat suitability index increased with mud content. The modelled distribution of F. quadrangularis indicated a deeper distribution than V. mirabilis or P. phosphorea and was not present in sediment with gravel content above 30%. Pennatula phosphorea had the smallest area of suitable habitat, while V. mirabilis had the largest. The percentage predicted suitable area for each species that was encompassed by the five pMPAs ranged from 11% for F. quadrangularis to 15% for P. phosphorea. Some of the largest areas predicted as suitable for F. quadrangularis lay outside the pMPAs. The model results indicated differences in the environmental requirements of the three species of sea pen that can be linked to the autecology of each species. Patch sizes, calculated from a binary output of the model, were used to estimate the degree of habitat fragmentation, thereby giving a partial assessment of the adequacy criterion for these pMPAs. The results suggest that potential MPAs within the study area cover sizeable areas of potential sea pen habitat. However, further areas suitable for F. quadrangularis could be considered.

scholarly journals Niche divergence corresponds to genetic differentiation within the parrot-beaked tortoise Homopus areolatus (Reptilia: Testudinidae), endemic to South Africa

2020 ◽  
Author(s):  
Margaretha D Hofmeyr ◽  
Flora Ihlow ◽  
Pierre Fouche ◽  
Savel R Daniels
Keyword(s):  
Genetic Differentiation ◽  
Habitat Suitability ◽  
Genetic Divergence ◽  
Taxonomic Status ◽  
Anthropogenic Factors ◽  
Suitable Habitat ◽  
The West ◽  
Niche Divergence ◽  
Rainfall Seasonality ◽  
Clade 1

Abstract We assessed genetic differentiation and habitat suitability for Homopus areolatus during current and Last Glacial Maximum (LGM) conditions. The ND4 locus retrieved two monophyletic mtDNA clades with lower diversity in clade 1, in the west, than in clade 2, in the south-east. Clade 1 showed a north–south and clade 2 a west-to-east genetic divergence, and the clades co-occur in the syntaxis zone of the Cape Fold Mountains. The clades occupy distinct niches with limited overlap. Rainfall seasonality contributed most to habitat suitability, with clade 1 being restricted to winter rainfall and clade 2 to all-year rainfall regions. Precipitation variables contributed 90% and 60%, respectively, to habitat suitability of clades 1 and 2, with temperature, particularly mean temperature of the driest quarter, being of greater importance for clade 2 than clade 1. Suitable habitat shrank from the LGM to current conditions, probably due to reduced rainfall in the west and higher temperatures in most regions. We conclude that patterns of genetic divergence are strongly associated with ecological niche divergence of H. areolatus clades. More studies are needed to assess the taxonomic status of clade 1, particularly in view of its shrinking habitat due to climate change and anthropogenic factors.

scholarly journals Accessing habitat suitability and connectivity for the westernmost population of Asian black bear (Ursus thibetanus gedrosianus, Blanford, 1877) based on climate changes scenarios in Iran

PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0242432
Author(s):  
Maryam Morovati ◽  
Peyman Karami ◽  
Fatemeh Bahadori Amjas
Keyword(s):  
Climate Change ◽  
Protected Areas ◽  
Habitat Suitability ◽  
Black Bear ◽  
Circuit Theory ◽  
Support Vector ◽  
Ensemble Model ◽  
Ursus Thibetanus ◽  
Annual Range ◽  
Suitable Habitats

Climate change, as an emerging phenomenon, has led to changes in the distribution, movement, and even risk of extinction of various wildlife species and this has raised concerns among conservation biologists. Different species have two options in the face of climate change, either to adopt or follow their climatic niche to new places through the connectivity of habitats. The modeling of interpatch landscape communications can serve as an effective decision support tool for wildlife managers. This study was conducted to assess the effects of climate change on the distribution and habitat connectivity of the endangered subspecies of Asian black bear (Ursus thibetanus gedrosianus) in the southern and southeastern Iran. The presence points of the species were collected in Provinces of Kerman, Hormozgan, and Sistan-Baluchestan. Habitat modeling was done by the Generalized Linear Model, and 3 machine learning models including Maximum Entropy, Back Propagation based artificial Neural Network, and Support Vector Machine. In order to achieve the ensemble model, the results of the mentioned models were merged based on the method of “accuracy rate as weight” derived from their validation. To construct pseudo-absence points for the use in the mentioned models, the Ensemble model of presence-only models was used. The modeling was performed using 15 habitat variables related to climatic, vegetation, topographic, and anthropogenic parameters. The three general circulation models of BCC-CSM1, CCSM4, and MRI-CGCM3 were selected under the two scenarios of RCP2.6 and RCP8.5 by 2070. To investigate the effect of climate change on the habitat connections, the protected areas of 3 provinces were considered as focal nodes and the connections between them were established based on electrical circuit theory and Pairwise method. The true skill statistic was employed to convert the continuous suitability layers to binary suitable/unsuitable range maps to assess the effectiveness of the protected areas in the coverage of suitable habitats for the species. Due to the high power of the stochastic forest model in determining the importance of variables, this method was used. The results showed that presence/absence models were successful in the implementation and well distinguished the points of presence and pseudo-absence from each other. Based on the random forests model, the variables of Precipitation of Driest Quarter, Precipitation of Coldest Quarter, and Temperature Annual Range have the greatest impact on the habitat suitability. Comparing the modeling findings to the realities of the species distribution range indicated that the suitable habitats are located in areas with high humidity and rainfall, which are mostly in the northern areas of Bandar Abbas, south of Kerman, and west and south of Sistan-Baluchestan. The area of suitable habitats, in the MRI-CGCM3 (189731 Km2) and CCSM4 (179007 Km2) models under the RCP2.6 scenario, is larger than the current distribution (174001 Km2). However, in terms of the performance of protected areas, the optimal coverage of the species by the boundary of the protected areas, under each of the RCP2.6 and RCP8.5 scenarios, is less than the present time. According to the electric circuit theory, connecting the populations in the protected areas of Sistan-Baluchestan province to those in the northern Hormozgan and the southern Kerman would be based on the crossing through the heights of Sistan-Baluchestan and Hormozgan provinces and the plains between these heights would be the movement pinch points under the current and future scenarios. Populations in the protected areas of Kerman have higher quality patch connections than that of the other two provinces. The areas such as Sang-e_Mes, Kouh_Shir, Zaryab, and Bahr_Aseman in Kerman Province and Kouhbaz and Geno in Hormozgan Province can provide suitable habitats for the species in the distribution models. The findings revealed that the conservation of the heights along with the caves inside them could be a protective priority to counteract the effects of climate change on the species.

scholarly journals Large carnivore habitat suitability modelling for Romania and associated predictions for protected areas

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6549 ◽  
Author(s):  
Bogdan Cristescu ◽  
Csaba Domokos ◽  
Kristine J. Teichman ◽  
Scott E. Nielsen
Keyword(s):  
Protected Areas ◽  
Habitat Suitability ◽  
Forest Type ◽  
National Level ◽  
Natura 2000 ◽  
Habitat Characteristics ◽  
Suitable Habitat ◽  
Lynx Lynx ◽  
Landscape Characteristics ◽  
Traffic Volumes

Habitat characteristics associated with species occurrences represent important baseline information for wildlife management and conservation, but have rarely been assessed for countries recently joining the EU. We used footprint tracking data and landscape characteristics in Romania to investigate the occurrence of brown bear (Ursus arctos), gray wolf (Canis lupus) and Eurasian lynx (Lynx lynx) and to compare model predictions between Natura 2000 and national-level protected areas (gap analysis). Wolves were more likely to occur where rugged terrain was present. Increasing proportion of forest was positively associated with occurrence of all large carnivores, but forest type (broadleaf, mixed, or conifer) generally varied with carnivore species. Areas where cultivated lands were extensive had little suitable habitat for lynx, whereas bear occurrence probability decreased with increasing proportion of built areas. Pastures were positively associated with wolf and lynx occurrence. Brown bears occurred primarily where national roads with high traffic volumes were at low density, while bears and lynx occurred at medium-high densities of communal roads that had lower traffic volumes. Based on predictions of carnivore distributions, natural areas protected in national parks were most suitable for carnivores, nature parks were less suitable, whereas EU-legislated Natura 2000 sites had the lowest probability of carnivore presence. Our spatially explicit carnivore habitat suitability predictions can be used by managers to amend borders of existing sites, delineate new protected areas, and establish corridors for ecological connectivity. To assist recovery and recolonization, management could also focus on habitat predicted to be suitable but where carnivores were not tracked.

scholarly journals Habitat suitability and connectivity inform a co-managed policy of protected areas networks for Asian elephants in China

2018 ◽  
Author(s):  
Cheng Huang ◽  
Xueyou Li ◽  
Laxman Khanal ◽  
Xuelong Jiang
Keyword(s):  
Protected Areas ◽  
Habitat Suitability ◽  
Forest Cover ◽  
Habitat Requirements ◽  
Suitable Habitat ◽  
Asian Elephants ◽  
Maximum Entropy Modeling ◽  
Economic Context ◽  
Level Of Economic Development

Enlarging protected areas (PAs) network is critical to ensure the long-term viability of Asian elephants from habitat fragmentation and loss. While challenges are raised in the strictly government-managed policy of PAs networks due to the difficulties in persuading participation of stakeholders and meeting habitat requirements of the elephants. This study hypothesized that a co-managed policy is more plausible than the strict policy to enlarge PAs network for Asian elephants in a “developing” world. We identified the suitable habitat for Asian elephants using the maximum entropy modeling approach (MaxEnt) and examined the socio-economic context of the habitat. The hypothesis was supported by our results: (1) Asian elephants prefer forest matrix with multiple land use (50% forest cover) rather than interior of large forest and roam in proximity of human habitations (mean distance 1.85 km); (2) suitability and the level of economic development of the habitats are negatively correlated (p = 0.04). Additionally, we provided an empirical study on corridor designing for the study area in China.

scholarly journals Habitat suitability and connectivity inform a co-managed policy of protected areas networks for Asian elephants in China

2018 ◽  
Author(s):  
Cheng Huang ◽  
Xueyou Li ◽  
Laxman Khanal ◽  
Xuelong Jiang
Keyword(s):  
Protected Areas ◽  
Habitat Suitability ◽  
Forest Cover ◽  
Habitat Requirements ◽  
Suitable Habitat ◽  
Asian Elephants ◽  
Maximum Entropy Modeling ◽  
Economic Context ◽  
Level Of Economic Development

Enlarging protected areas (PAs) network is critical to ensure the long-term viability of Asian elephants from habitat fragmentation and loss. While challenges are raised in the strictly government-managed policy of PAs networks due to the difficulties in persuading participation of stakeholders and meeting habitat requirements of the elephants. This study hypothesized that a co-managed policy is more plausible than the strict policy to enlarge PAs network for Asian elephants in a “developing” world. We identified the suitable habitat for Asian elephants using the maximum entropy modeling approach (MaxEnt) and examined the socio-economic context of the habitat. The hypothesis was supported by our results: (1) Asian elephants prefer forest matrix with multiple land use (50% forest cover) rather than interior of large forest and roam in proximity of human habitations (mean distance 1.85 km); (2) suitability and the level of economic development of the habitats are negatively correlated (p = 0.04). Additionally, we provided an empirical study on corridor designing for the study area in China.

scholarly journals Predicting the impact of climate change on the distribution pattern of Agamura persica (Dumeril, 1856) (Squamata: Gekkonidae) in Iran

2017 ◽  
Vol 147 (2) ◽  
Author(s):  
Sayyed Saeed Hosseinian Yousefkhani ◽  
Mansour Aliabadian ◽  
Eskandar Rastegar-Pouyani ◽  
Jamshid Darvish
Keyword(s):  
Climate Change ◽  
Species Distribution ◽  
Habitat Suitability ◽  
Vegetation Type ◽  
Area Under The Curve ◽  
Suitable Habitat ◽  
Ecological Data ◽  
Central Plateau ◽  
Impact Of Climate Change ◽  
The Impact

Species distribution modeling is an important tool that uses ecological data to aid in biological conservation. In the present study we used prediction methods, including maximum entropy (Maxent), to project the distribution of the Persian Spider gecko and the impact of climate change on its distribution in Iran. The results were consistent between models and indicated that two of the most important variables in determining distribution of Agamura persica are mean temperature of the wettest quarter and temperature seasonality. All of the models used in this study obtained high area-under-the-curve (AUC) values. Because of the nocturnal behavior of the species, these variables can directly affect species’ activity by determining the vegetation type in habitat. Suitable habitats of Agamura persica were in two locations in eastern Iran and a third location in the central plateau. Habitat suitability for this species was increased in the last glacial maximum (LGM), at which time most parts of the Iranian Plateau were suitable (even southwest Iran). However, the suitable habitat area is restricted to the central part of the plateau in the current period. Predictions from four scenarios indicate that future habitat suitability will be patchy and that the central part of the plateau will remain the most important part of the species distribution.

scholarly journals A distribution model for Glossina brevipalpis and Glossina austeni in Southern Mozambique, Eswatini and South Africa for enhanced area-wide integrated pest management approaches

2021 ◽  
Vol 15 (11) ◽  
pp. e0009989
Author(s):  
Chantel J. de Beer ◽  
Ahmadou H. Dicko ◽  
Jerome Ntshangase ◽  
Percy Moyaba ◽  
Moeti O. Taioe ◽  
...  
Keyword(s):  
South Africa ◽  
Protected Areas ◽  
Species Distribution ◽  
Habitat Suitability ◽  
Species Distribution Model ◽  
Distribution Model ◽  
Distribution Models ◽  
Glossina Austeni ◽  
Suitability Maps ◽  
Glossina Brevipalpis

Background Glossina austeni and Glossina brevipalpis (Diptera: Glossinidae) are the sole cyclical vectors of African trypanosomes in South Africa, Eswatini and southern Mozambique. These populations represent the southernmost distribution of tsetse flies on the African continent. Accurate knowledge of infested areas is a prerequisite to develop and implement efficient and cost-effective control strategies, and distribution models may reduce large-scale, extensive entomological surveys that are time consuming and expensive. The objective was to develop a MaxEnt species distribution model and habitat suitability maps for the southern tsetse belt of South Africa, Eswatini and southern Mozambique. Methodology/Principal findings The present study used existing entomological survey data of G. austeni and G. brevipalpis to develop a MaxEnt species distribution model and habitat suitability maps. Distribution models and a checkerboard analysis indicated an overlapping presence of the two species and the most suitable habitat for both species were protected areas and the coastal strip in KwaZulu-Natal Province, South Africa and Maputo Province, Mozambique. The predicted presence extents, to a small degree, into communal farming areas adjacent to the protected areas and coastline, especially in the Matutuíne District of Mozambique. The quality of the MaxEnt model was assessed using an independent data set and indicated good performance with high predictive power (AUC > 0.80 for both species). Conclusions/Significance The models indicated that cattle density, land surface temperature and protected areas, in relation with vegetation are the main factors contributing to the distribution of the two tsetse species in the area. Changes in the climate, agricultural practices and land-use have had a significant and rapid impact on tsetse abundance in the area. The model predicted low habitat suitability in the Gaza and Inhambane Provinces of Mozambique, i.e., the area north of the Matutuíne District. This might indicate that the southern tsetse population is isolated from the main tsetse belt in the north of Mozambique. The updated distribution models will be useful for planning tsetse and trypanosomosis interventions in the area.

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