scholarly journals Habitat of the Vulnerable Formosan sambar deerRusa unicolor swinhoiiin Taiwan

Oryx ◽  
2013 ◽  
Vol 48 (2) ◽  
pp. 232-240 ◽  
Author(s):  
Shih-Ching Yen ◽  
Ying Wang ◽  
Heng-You Ou

AbstractThe sambar deerRusa unicoloris categorized as Vulnerable on the IUCN Red List because of continuous population decline across its native range. In Taiwan the Formosan sambar deerR. unicolor swinhoiiis listed as a protected species under the Wildlife Conservation Act because of human overexploitation. However, its population status remains unclear. We used presence and absence data from line transect and camera-trap surveys to identify key habitat variables and to map potential habitats available to this subspecies in Taiwan. We applied five habitat-suitability models: logistic regression, discriminant analysis, ecological-niche factor analysis, genetic algorithm for rule-set production, and maximum entropy. We then combined the results of all five models into an ensemble-forecasting model to facilitate a more robust prediction. This model indicated the existence of 7,865 km2of suitable habitat for the sambar deer. Distance from roads and elevation were identified as the most important environmental variables for habitat suitability, and deer preferred areas far from roads and > 1,500 m altitude. The results predicted that suitable deer habitat is mainly located in Taiwan's Central Mountain Range and Xue Mountain Range, with c. 70% of this suitable habitat in protected areas. However, the habitat predicted to be suitable is in five areas separated by mountain highways. We recommend that deer habitats close to the highways should be monitored for the future establishment of corridors between Formosan sambar deer sub-populations.

2021 ◽  
Vol 42 (3(SI)) ◽  
pp. 806-811
Author(s):  
N.F. Khodri ◽  
◽  
T. Lihan ◽  
M.A. Mustapha ◽  
T.M. Taher ◽  
...  

Aim: This research assessed the distribution of leopard to predict the habitat suitability in Taman Negara National Park and adjacent forest area. Methodology: Environmental factors for habitat suitability were derived from geographical information system (GIS) data such as elevation, slope, land-use, distance from urban and distance from river. Leopard presence data from 1993 to 2008 were integrated with the environmental parameters using maximum entropy (MaxEnt) modeling to assess habitat suitability across the study area. Results: The results showed that distance from river contributed the most (39.3%) in the habitat suitability modeling followed by distance from urban (31.4%), elevation (12.3%), land use types (10.1%), and slope (6.9%). Distance from river and urban showed highest contribution that influenced leopard distribution in which most suitable habitat occurred in proximity with river and further from urban. Habitat suitability of leopard were distributed among 48% over 2,218,389 ha of the study area. Interpretation: The findings of this study provides knowledge on how the species move and exploit different habitat niches for more effective conservation management. It provide models for future wildlife conservation and urban planning.


2019 ◽  
Vol 5 (2) ◽  
pp. 62-71
Author(s):  
Mananya Pla-ard ◽  
Ronglarp Sukmasuang ◽  
Khanchit Srinopawan

Abstract The aim of this study was to investigate the population and habitat of wild elephants in the Khao Yai National Park, to provide elephant population densities using the line transect method. Habitat suitability was also assessed based on the data obtained from the location of the species during monthly ranger patrol across the park area, with the rate of dung decay used for population calculation. The population structure and age class were studied by direct observation to estimate the population trend. On the basis of 116 systematic transect lines that were 2 km in length and separated by 500-m intervals, a total of 1,209 elephant dung piles were found in more than 213.20 km. The analysis of the combined data showed that the dung density was 531.49 dung piles/km2, with a decay rate of 0.0039 dung piles/day based on 56 dung piles checked every 7 days. The annual data showed that the population density was 0.15 individuals/km2. The population structure comprising calf:juvenile:subadult:adult was 1: 1.09:1.14:2.10; the sex ratio of adult male to adult female elephants was 1:1.10; and the ratio of reproductive ability among adult females, juveniles, and calves was 1.00:0.99:0.90. The combined data also showed that the main environmental factor affecting the presence of the animals was salt lick sites. The pooled data analysis found that the habitat most suitable for the elephants covered an area of 220.59 km2. The habitat suitability, based on the dry season appearance data, covered an area of 258.64 km2, whereas during the wet season, it covered an area of 517.45 km2. As the most suitable habitat for elephants appears around the park boundary, habitat improvements for wild elephants should address the central areas of the national park. A greater emphasis should be placed on creating salt licks, being far from human activity sites.


Oryx ◽  
2013 ◽  
Vol 48 (4) ◽  
pp. 540-547 ◽  
Author(s):  
C. N. Z. Coudrat ◽  
C. Nanthavong ◽  
K. A. I. Nekaris

AbstractThe Endangered red-shanked douc Pygathrix nemaeus is a charismatic Asian colobine endemic to Vietnam, Cambodia and Lao People's Democratic Republic (PDR). The largest population is found in central-eastern Lao PDR but it has never been quantified. We conducted line-transect surveys in Nakai–Nam Theun National Protected Area in 2011–2012. We used distance sampling combined with a habitat suitability model to estimate group density and group abundance in the area. Our analysis yielded a density of 2.8 (range 1.9–4.1) groups per km2 and c. 4,420 groups within the predicted c. 1,600 km2 of suitable habitat in Nakai–Nam Theun. These are the only available data for P. nemaeus in Lao PDR to date. We discuss the limitations of our survey, which involved potential violations of the distance sampling method, and highlight the challenges of using this method for primates. We also consider the importance of assessing limitations in distance sampling studies, to evaluate reliability and facilitate comparisons. The population of P. nemaeus in Lao PDR is under threat from illegal hunting and is not the focus of any specific conservation action. To avoid a repetition of the decline the species has already experienced in Vietnam, and to secure the species' global survival, conservation projects need to target the population in Nakai–Nam Theun. A long-term conservation and research project in this key biodiversity area will also benefit other threatened and unique co-existing species.


2018 ◽  
Vol 10 (8) ◽  
pp. 11999 ◽  
Author(s):  
Saru Rimal ◽  
Hari Adhikari ◽  
Shankar Tripathi

The Greater One-horned Rhinoceros Rhinoceros unicornis has been listed as a Vulnerable species on IUCN Red List, Appendix I of CITES, and a protected animal under the National Parks and Wildlife Conservation Act 2029 B.S., 1973.  In Nepal, it was found only in Chitwan, Bardia, Shuklaphanta and Parsa national parks, but it has recently been also reported from the forests of Rautahat.  The main objectives of the study were to assess habitat suitability and threats for rhinoceros in Rautahat at an elevation range of approximately 300–1,000 m.  Remote sensing data and geospatial modeling techniques were used to assess habitat suitability of rhinoceros.  Vegetation assessment was carried out for tree, shrubs, and herbs of plot size 10m × 10m, 5m × 5m, 1m × 1m respectively for habitat suitability.  Threat analysis was carried out using purposive sampling among local people and their perceptions were collected on the movement of rhinoceros and threats.  The integration of nine explanatory variables showed that about 0.06%, 29.18%, 20.45%, and 50.31% of the study area was found to be most suitable, suitable, moderately suitable and unsuitable habitat respectively for rhinoceros.  Out of 30 respondents, 37%, 23%, 20%, and 20% identified the main threat to rhinoceros to be unmanaged habitat, poaching, human-wildlife conflict and environmental factors, respectively.  This study recommends parts of the Rautahat District to be extended as the habitat of rhinoceros and starting of immediate conservation initiatives in the area.  


2011 ◽  
Vol 366 (1578) ◽  
pp. 2633-2641 ◽  
Author(s):  
Carlo Rondinini ◽  
Moreno Di Marco ◽  
Federica Chiozza ◽  
Giulia Santulli ◽  
Daniele Baisero ◽  
...  

Detailed large-scale information on mammal distribution has often been lacking, hindering conservation efforts. We used the information from the 2009 IUCN Red List of Threatened Species as a baseline for developing habitat suitability models for 5027 out of 5330 known terrestrial mammal species, based on their habitat relationships. We focused on the following environmental variables: land cover, elevation and hydrological features. Models were developed at 300 m resolution and limited to within species' known geographical ranges. A subset of the models was validated using points of known species occurrence. We conducted a global, fine-scale analysis of patterns of species richness. The richness of mammal species estimated by the overlap of their suitable habitat is on average one-third less than that estimated by the overlap of their geographical ranges. The highest absolute difference is found in tropical and subtropical regions in South America, Africa and Southeast Asia that are not covered by dense forest. The proportion of suitable habitat within mammal geographical ranges correlates with the IUCN Red List category to which they have been assigned, decreasing monotonically from Least Concern to Endangered. These results demonstrate the importance of fine-resolution distribution data for the development of global conservation strategies for mammals.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Zhenhua Luo ◽  
Xiaoyi Wang ◽  
Shaofa Yang ◽  
Xinlan Cheng ◽  
Yang Liu ◽  
...  

Abstract Background Understanding the impacts of past and contemporary climate change on biodiversity is critical for effective conservation. Amphibians have weak dispersal abilities, putting them at risk of habitat fragmentation and loss. Both climate change and anthropogenic disturbances exacerbate these risks, increasing the likelihood of additional amphibian extinctions in the near future. The giant spiny frog (Quasipaa spinosa), an endemic species to East Asia, has faced a dramatic population decline over the last few decades. Using the giant spiny frog as an indicator to explore how past and future climate changes affect landscape connectivity, we characterized the shifts in the suitable habitat and habitat connectivity of the frog. Results We found a clear northward shift and a reduction in the extent of suitable habitat during the Last Glacial Maximum for giant spiny frogs; since that time, there has been an expansion of the available habitat. Our modelling showed that “overwarm” climatic conditions would most likely cause a decrease in the available habitat and an increase in the magnitude of population fragmentation in the future. We found that the habitat connectivity of the studied frogs will decrease by 50–75% under future climate change. Our results strengthen the notion that the mountains in southern China and the Sino-Vietnamese transboundary regions can act as critical refugia and priority areas of conservation planning going forward. Conclusions Given that amphibians are highly sensitive to environmental changes, our findings highlight that the responses of habitat suitability and connectivity to climate change can be critical considerations in future conservation measures for species with weak dispersal abilities and should not be neglected, as they all too often are.


2021 ◽  
Author(s):  
Andri A Wibowo

Babirusa is a mammal belongs to Suidae family. This mammal belongs to Babyrousa genus is known endemic to Indonesia. Recently there are 3 species of Babyrousa, one species is Babyrousa babyrussa, listed as Vulnerable on the IUCN Red List of Threatened Species. Babyrousa occurs in Indonesia on Sulawesi island, Togian, Sula islands, and Taliabu, Mangole and Buru islands in the Molucca regions. The Moluccan Babirusa is now restricted to upland forests and mountainous terrain. Then this study aims to assess the suitability of Buru island as habitat for Moluccan Babirusa. The suitability analysis was based on GIS analysis using 4 determinant environmental variables required by B. babyrussa species including NDVI, barren soil, elevation, and river network. The particular location was a Batabual landscape sizing 292.60 km2 located in the east parts of Buru island. Based on NDVI, less vegetation covers were observed in north and east parts of Batabual. In contrast, NDVI values were higher in the central, west, and south indicating that half of the landscape was covered by intact primary forest. Batabual has a hilly landscape surrounded by coastal areas with hilly areas were observed in the south and west. There were 2 river streams in the east parts. The analysis has divided the landscape into several parts based on the habitat suitability levels. About one third of the landscape located in north was considered less and not suitable for Babirusa. Some areas in west were also considered moderate to be inhabited by Babirusa considering a presence of hilly landscape that may limit the vertical distribution of Babirusa. Most suitable habitats were estimated in central parts of the landscape spanning to the south. South parts of the landscape were characterized by high NDVI values and forest covers then these areas were considered as suitable habitats for Babirusa. The size of this suitable habitat was estimated around 188.62 km2 or more than half of the size (64.46%) of Batabual landscape.


2010 ◽  
Vol 20 (4) ◽  
pp. 410-431 ◽  
Author(s):  
JUAN F. FREILE ◽  
JUAN LUIS PARRA ◽  
CATHERINE H. GRAHAM

SummaryThe current ranges of many tropical species of conservation concern are poorly known, yet this information is critical for assessing their conservation status against the IUCN Red List criteria and implementing species-level management. Antpittas in the generaGrallariaandGrallariculaare elusive, ground-foraging insectivores, highly susceptible to a range of threats. For these genera, we combine environmental niche modelling with expert knowledge in order to predict species’ geographic distributions, and we use current estimates of deforestation to evaluate their conservation status in Ecuador. We use BIOCLIM to generate a first pass geographic prediction, which was further aided by expert knowledge of their natural history. This methodology allowed us to assess the conservation status of each species, revising previous assessments at the national level and making recommendations for revision of global IUCN Red List categories. Based on inferred rates of population decline, derived from estimates of loss of suitable habitat, we suggest ranking three species as ‘Endangered’ in Ecuador, one as 'Vulnerable', and three as ‘Near Threatened’. Predicted national ranges vary in size from 56.05 km2to 112,745 km2. Patterns of range loss were different for each Andean slope, with higher deforestation on the western slope. The combination of niche modelling and knowledge of habitat loss can be a powerful tool to aid conservation efforts in the face of a poor understanding of population demographics, as is the case for many Neotropical taxa. We hope the methodology and results provided here will increase our understanding, and focus future attention on the conservation of this poorly known avian group.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6791 ◽  
Author(s):  
Cheng Huang ◽  
Xueyou Li ◽  
Laxman Khanal ◽  
Xuelong Jiang

Enlarging protected area networks (PANs) is critical to ensure the long-term population viability of Asian elephants (Elephas maximus), which are threatened by habitat loss and fragmentation. Strict policies of PAN enlargement that focus on wildlife conservation have failed largely due to difficulties in encouraging stakeholder participation and meeting the elephant habitat requirement. A co-management policy that promotes sustainable resource use, wildlife conservation, and stakeholder participation may have greater feasibility than the strict policies in a developing world. Here, we identified the suitable habitat of elephants using maximum entropy models and examined whether habitat suitability is indirectly associated with local economic development in human-dominated landscapes. We found that (1) the suitable habitat was mainly in areas of forest matrix (50% natural forest cover) with multiple land-use practices rather than relatively intact forest and near communities (mean distance two km) and (2) habitat suitability was negatively associated with local economic development (rP = −0.37, P = 0.04). From the standpoint of elephant habitat and its socio-economic background, our results indicate that co-management will be more effective than the currently strict approaches of enlarging PAN. Additionally, our results provide on-ground information for elephant corridor design in southern China.


2020 ◽  
Vol 641 ◽  
pp. 159-175
Author(s):  
J Runnebaum ◽  
KR Tanaka ◽  
L Guan ◽  
J Cao ◽  
L O’Brien ◽  
...  

Bycatch remains a global problem in managing sustainable fisheries. A critical aspect of management is understanding the timing and spatial extent of bycatch. Fisheries management often relies on observed bycatch data, which are not always available due to a lack of reporting or observer coverage. Alternatively, analyzing the overlap in suitable habitat for the target and non-target species can provide a spatial management tool to understand where bycatch interactions are likely to occur. Potential bycatch hotspots based on suitable habitat were predicted for cusk Brosme brosme incidentally caught in the Gulf of Maine American lobster Homarus americanus fishery. Data from multiple fisheries-independent surveys were combined in a delta-generalized linear mixed model to generate spatially explicit density estimates for use in an independent habitat suitability index. The habitat suitability indices for American lobster and cusk were then compared to predict potential bycatch hotspot locations. Suitable habitat for American lobster has increased between 1980 and 2013 while suitable habitat for cusk decreased throughout most of the Gulf of Maine, except for Georges Basin and the Great South Channel. The proportion of overlap in suitable habitat varied interannually but decreased slightly in the spring and remained relatively stable in the fall over the time series. As Gulf of Maine temperatures continue to increase, the interactions between American lobster and cusk are predicted to decline as cusk habitat continues to constrict. This framework can contribute to fisheries managers’ understanding of changes in habitat overlap as climate conditions continue to change and alter where bycatch interactions could occur.


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