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1.
Ecol Evol ; 14(4): e11270, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38633522

ABSTRACT

The Sichuan golden snub-nosed monkey (Rhinopithecus roxellana) is a rare and endangered primate species endemic to China. Conducting research on the population distribution changes of the Sichuan golden snub-nosed monkey holds paramount importance for its conservation. Our study represented a comprehensive investigation into the population distribution of the Sichuan snub-nosed monkey by integrating data acquired from field surveys, protected areas, and historical records and using Geographic Information Systems (GIS) to explore changes in distribution across various time periods, including the historical (the Mid-to-Late Pleistocene), recent (1980-2000), and current (2001-2023). The research findings demonstrate a significant shift in the distribution range of the Sichuan golden snub-nosed monkey compared to historical time frames. Notably, between 1980 and 2000, there was a sharp decline in distribution area. Analyses revealed that the southernmost distribution county for the Sichuan golden snub-nosed monkey in Sichuan Province has shifted northward from Huili to Kangding. Furthermore, distribution changes in Sichuan Province are not solely characterized by a reduction in habitat area but also by a decrease in vertical distribution zones. Regions in the northeastern part of Sichuan with elevations below 1000 m, such as Guang'an City, Bazhong City, Dazhou City, and Nanchong City, no longer support the presence of the Sichuan golden snub-nosed monkey. At present, the distribution range is confined to elevations between 1000 and 4000 m in the two major mountain ranges of Qionglai and Minshan. A holistic approach is required to safeguard this species. The establishment of movement corridors can play a critical role in enhancing the overall connectivity of current distribution areas. Additionally, we propose implementing a hierarchical approach to protect current habitats. Spatially differentiated conservation measures should be implemented to prioritize the protection of key habitats while simultaneously monitoring anthropogenic activities in non-key habitats to prevent further fragmentation and isolation of the monkey's distribution areas.

2.
Animals (Basel) ; 12(11)2022 May 31.
Article in English | MEDLINE | ID: mdl-35681886

ABSTRACT

Personal injury and property damage caused by wildlife can worsen the relationship between humans and wildlife. In recent years, conflicts between herders and Tibetan brown bears (Ursus arctos pruinosus) (human-bear conflicts; HBCs) on the Qinghai-Tibetan Plateau have increased dramatically, severely affecting community motivation for the conservation of brown bears and other species. Understanding the types, effectiveness, and flaws of current HBC mitigation measures is critical to develop effective strategies to alleviate HBC. From 2017 to 2019, we conducted a systematic field survey regarding HBCs on the Qinghai-Tibetan Plateau. In addition, we invited bear specialists and multiple interest groups to hold an HBC seminar and proposed some potential mitigation strategies. We surveyed 312 families via semi-structured interviews and documented 16 types of HBC mitigation measures. A total of 96% of respondents were using more than two mitigation measures simultaneously. The effectiveness evaluation of HBC mitigation measures showed that: (1) removing food from winter homes while herders were at their summer pastures and asking people to keep watch of winter homes were effective at protecting food and houses; (2) traditional grazing methods (human guarding of livestock all day) and solar soundboxes (attached to livestock) were effective at protecting free-range livestock; (3) solar street lights had a deterrent effect on brown bears and were effective in protecting livestock, houses, and people; and (4) due to the unstable power supply of photovoltaic cells and improper installation of ground wires, electric fences were not ideal in practice. Evaluation of the potential mitigation measures at the seminar showed that upgrading electric fence technology, expanding electric fence pilot areas, installing diversionary feeders, and introducing bear spray were the most optimal solutions. This study provides a scientific basis for creating human-bear coexistence plans on the Qinghai-Tibet Plateau.

3.
Ecol Evol ; 11(23): 17202-17218, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34938503

ABSTRACT

Assessing species' vulnerability to climate change is a prerequisite for developing effective strategies to reduce emerging climate-related threats. We used the maximum entropy algorithm (MaxEnt model) to assess potential changes in suitable snow leopard (Panthera uncia) habitat in Qinghai Province, China, under a mild climate change scenario. Our results showed that the area of suitable snow leopard habitat in Qinghai Province was 302,821 km2 under current conditions and 228,997 km2 under the 2050s climatic scenario, with a mean upward shift in elevation of 90 m. At present, nature reserves protect 38.78% of currently suitable habitat and will protect 42.56% of future suitable habitat. Current areas of climate refugia amounted to 212,341 km2 and are mainly distributed in the Sanjiangyuan region, Qilian mountains, and surrounding areas. Our results provide valuable information for formulating strategies to meet future conservation challenges brought on by climate stress. We suggest that conservation efforts in Qinghai Province should focus on protecting areas of climate refugia and on maintaining or building corridors when planning for future species management.

4.
Sci Total Environ ; 772: 145012, 2021 Jun 10.
Article in English | MEDLINE | ID: mdl-33581527

ABSTRACT

Personal injury and property loss caused by wildlife often deteriorates the relationship between humans and animals, prompting retaliatory killings that threaten species survival. Conflicts between humans and Tibetan brown bears (Ursus arctos pruinosus) (Human-Bear Conflicts, HBC) in the Sanjiangyuan region have recently dramatically increased, seriously affecting community enthusiasm for brown bears and the conservation of other species. In order to understand the driving mechanisms of HBC, we proposed six potential drivers leading to increased occurrences of HBC. We conducted field research in Zhiduo County of the Sanjiangyuan region from 2017 to 2019 to test hypotheses through semi-constructed interviews, marmot (Marmota himalayana) density surveys and brown bear diet analysis based on metagenomic sequencing. Analysis of herder perceptions revealed that the driving factors of HBC were related to changes in their settlement practice and living habits, changes in foraging behavior of brown bears and recovery of the brown bear population. Since the establishment of winter homes, brown bears have gradually learned to utilize the food in unattended homes. Although 91.4% (n = 285) of the respondents no longer store food in unattended homes, brown bears were reported to still frequently approach winter homes for food due to improper disposal of dead livestock and household garbage. The frequency and abundance of marmots were found to be high in brown bear diet, indicating that marmots were the bears' primary food. However, marmot density had no significant effect on brown bears utilizing human food (P = 0.329), and HBC appears to not be caused by natural food shortages. Distance to rocky outcrops (P = 0.022) and winter homes (P = 0.040) were the key factors linked to brown bears pursuing human food. The number of brown bears has increased over the past decade, and HBC is likely linked to its population recovery. Our findings will provide scientific basis for formulating effective mitigation measures and protection countermeasures for brown bears.


Subject(s)
Ursidae , Animals , China , Humans , Seasons
5.
PeerJ ; 8: e10353, 2020.
Article in English | MEDLINE | ID: mdl-33304652

ABSTRACT

Understanding animals' migration, distribution and activity patterns is vital for the development of effective conservation action plans; however, such data for many species are lacking. In this study, we used camera trapping to document the spatial and temporal activity patterns of golden takins (Budorcas taxicolor bedfordi) in Changqing National Nature Reserve in the Qinling mountains, China, from April 2014 to October 2017. Our study obtained 3,323 independent detections (from a total of 12,351 detections) during a total camera trapping effort of 93,606 effective camera trap days at 573 sites. Results showed that: (1) the golden takin's utilization distributions showed seasonal variation, with larger utilization distributions during spring and autumn compared to summer and winter; (2) the species was recorded at the highest elevations in July, and lowest elevations in December, with the species moving to higher-elevations in summer, lower-elevations in spring and autumn; (3) during all four seasons, golden takins showed bimodal activity peaks at dawn and dusk, with activity intensity higher in the second peak than the first, and overall low levels of activity recorded from 20:00-06:00; and (4) there were two annual activity peaks, the first being in April and the second in November, with camera capture rate during these two months higher than in other months, and activity levels in spring and autumn higher than in summer and winter. This study is the first application of camera traps to assess the spatial and temporal activity patterns of golden takins at a population level. Our findings suggest that the proposed national park should be designed to include golden takin habitat and that ongoing consistent monitoring efforts will be crucial to mitigating novel and ongoing threats to the species.

6.
Ecol Evol ; 9(23): 13278-13293, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31871644

ABSTRACT

Climate change has direct impacts on wildlife and future biodiversity protection efforts. Vulnerability assessment and habitat connectivity analyses are necessary for drafting effective conservation strategies for threatened species such as the Tibetan brown bear (Ursus arctos pruinosus). We used the maximum entropy (MaxEnt) model to assess the current (1950-2000) and future (2041-2060) habitat suitability by combining bioclimatic and environmental variables, and identified potential climate refugia for Tibetan brown bears in Sanjiangyuan National Park, China. Next, we selected Circuit model to simulate potential migration paths based on current and future climatically suitable habitat. Results indicate a total area of potential suitable habitat under the current climate scenario of approximately 31,649.46 km2, of which 28,778.29 km2 would be unsuitable by the 2050s. Potentially suitable habitat under the future climate scenario was projected to cover an area of 23,738.6 km2. Climate refugia occupied 2,871.17 km2, primarily in the midwestern and northeastern regions of Yangtze River Zone, as well as the northern region of Yellow River Zone. The altitude of climate refugia ranged from 4,307 to 5,524 m, with 52.93% lying at altitudes between 4,300 and 4,600 m. Refugia were mainly distributed on bare rock, alpine steppe, and alpine meadow. Corridors linking areas of potentially suitable brown bear habitat and a substantial portion of paths with low-resistance value were distributed in climate refugia. We recommend various actions to ameliorate the impact of climate change on brown bears, such as protecting climatically suitable habitat, establishing habitat corridors, restructuring conservation areas, and strengthening monitoring efforts.

7.
Ecol Evol ; 9(24): 13979-13990, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31938496

ABSTRACT

Damage to homesteads by brown bears (Ursus arctos) has become commonplace in Asia, Europe, and the Americas. Science-based solutions for preventing damages can contribute to the establishment of mechanisms that promote human-bear coexistence. We examined the spatial distribution patterns of house break-ins by Tibetan brown bears (U. a. pruinosus) in Zhiduo County of the Sanjiangyuan region in China. Occurrence points of bear damage were collected from field surveys completed from 2017 to 2019. The maximum entropy (MaxEnt) model was then used to assess house break-in risk. Circuit theory modeling was used to simulate risk diffusion paths based on the risk map generated from our MaxEnt model. The results showed that (a) the total risk area of house break-ins caused by brown bears was 11,577.91 km2, accounting for 29.85% of Zhiduo County, with most of the risk areas were distributed in Sanjiangyuan National Park, accounting for 58.31% of the total risk area; (b) regions of alpine meadow located in Sanjiangyuan National Park with a high human population density were associated with higher risk; (c) risk diffusion paths extended southeast to northwest, connecting the inside of Sanjiangyuan National Park to its outside border; and (d) eastern Suojia, southern Zhahe, eastern Duocai, and southern Jiajiboluo had more risk diffusion paths than other areas examined, indicating higher risk for brown bear break-ins in these areas. Risk diffusion paths will need strong conservation management to facilitate migration and gene flow of brown bears and to alleviate bear damage, and implementation of compensation schemes may be necessary in risk areas to offset financial burdens. Our analytical methods can be applied to conflict reduction efforts and wildlife conservation planning across the Qinghai-Tibet Plateau.

8.
J Hered ; 108(6): 597-607, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28498961

ABSTRACT

The snow leopard, Panthera uncia, is an elusive high-altitude specialist that inhabits vast, inaccessible habitat across Asia. We conducted the first range-wide genetic assessment of snow leopards based on noninvasive scat surveys. Thirty-three microsatellites were genotyped and a total of 683 bp of mitochondrial DNA sequenced in 70 individuals. Snow leopards exhibited low genetic diversity at microsatellites (AN = 5.8, HO = 0.433, HE = 0.568), virtually no mtDNA variation, and underwent a bottleneck in the Holocene (∼8000 years ago) coinciding with increased temperatures, precipitation, and upward treeline shift in the Tibetan Plateau. Multiple analyses supported 3 primary genetic clusters: (1) Northern (the Altai region), (2) Central (core Himalaya and Tibetan Plateau), and (3) Western (Tian Shan, Pamir, trans-Himalaya regions). Accordingly, we recognize 3 subspecies, Panthera uncia irbis (Northern group), Panthera uncia uncia (Western group), and Panthera uncia uncioides (Central group) based upon genetic distinctness, low levels of admixture, unambiguous population assignment, and geographic separation. The patterns of variation were consistent with desert-basin "barrier effects" of the Gobi isolating the northern subspecies (Mongolia), and the trans-Himalaya dividing the central (Qinghai, Tibet, Bhutan, and Nepal) and western subspecies (India, Pakistan, Tajikistan, and Kyrgyzstan). Hierarchical Bayesian clustering analysis revealed additional subdivision into a minimum of 6 proposed management units: western Mongolia, southern Mongolia, Tian Shan, Pamir-Himalaya, Tibet-Himalaya, and Qinghai, with spatial autocorrelation suggesting potential connectivity by dispersing individuals up to ∼400 km. We provide a foundation for global conservation of snow leopard subspecies, and set the stage for in-depth landscape genetics and genomic studies.


Subject(s)
Genetic Speciation , Genetic Variation , Genetics, Population , Panthera/genetics , Animals , Asia , Bayes Theorem , Cluster Analysis , DNA, Mitochondrial/genetics , Microsatellite Repeats , Panthera/classification , Phylogeography , Sequence Analysis, DNA
9.
Clin Nucl Med ; 41(10): e443-4, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27488427

ABSTRACT

The recently introduced PSMA PET has developed as a powerful imaging tool for staging of prostate cancer. This case showed an intense uptake of Ga-PSMA in a soft-tissue mass of the rectus femoris muscle. Histopathology revealed the diagnosis of fasciitis nodularis. Therefore, it advises caution particularly in patients with solitary and atypical located lesions as they might not be indicative for metastatic prostate cancer, but eventually be caused by different conditions.


Subject(s)
Antigens, Surface/metabolism , Fasciitis/diagnostic imaging , Fasciitis/metabolism , Gallium Radioisotopes , Glutamate Carboxypeptidase II/metabolism , Magnetic Resonance Imaging , Positron-Emission Tomography , Prostatic Neoplasms/pathology , Diagnosis, Differential , Humans , Male , Middle Aged , Neoplasm Metastasis , Protein Transport
10.
Zoo Biol ; 35(4): 355-61, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27291643

ABSTRACT

Elephants in the wild face several conservation issues. With the rebranding of zoos as conservation and education pioneers, they have the ability to both educate and inspire guests to action. The purpose of this research was to analyze visitor perceptions and attitudes toward elephant conservation and outcomes post-exhibit visit. A one-page survey was randomly administered to assess perceptions of elephant behavior, attitudes about elephant conservation, and intended conservation-related outcomes from September 2013 to January 2014. Principle component analysis identified three major components: concern for elephants in zoos, importance of elephants in the wild, and modification of nature. Visitors who scored highly on conservation intent were those with positive attitudes towards elephants in the wild and negative attitudes regarding the modification of nature. The greatest changes in conservation intent were a result of a self-reported up-close encounter and the ability to witness active behaviors. Providing guests with the opportunity to witness or experience such occurrences may aid in a more successful delivery of the zoo's conservation message. Further research into guest emotions and affective states in relation to viewing elephants in a zoological institution would provide greater insight into improving the guest experience and helping zoos meet their conservation mission. Zoo Biol. 35:355-361, 2016. © 2016 Wiley Periodicals, Inc.


Subject(s)
Animals, Zoo , Attitude , Conservation of Natural Resources , Elephants , Perception , Adolescent , Adult , Animals , Behavior, Animal , California , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , Young Adult
11.
J Appl Anim Welf Sci ; 19(3): 271-9, 2016.
Article in English | MEDLINE | ID: mdl-26963741

ABSTRACT

With increased scrutiny surrounding the welfare of elephants in zoological institutions, it is important to have empirical evidence on their current welfare status. If elephants are not receiving adequate exercise, it could lead to obesity, which can lead to many issues including acyclicity and potentially heart disease. The goal of the current study was to compare the walking rates of elephants in the wild versus elephants in zoos to determine if elephants are walking similar distances relative to their wild counterparts. Eleven wild elephants throughout different habitats and locations in Botswana were compared to 8 elephants at the San Diego Zoo Safari Park. Direct comparisons revealed no significant difference in average walking rates of zoo elephants when compared with wild elephants. These results suggest that elephants at the San Diego Zoo Safari Park walk similar rates to those of wild elephants and may be meeting their exercise needs.


Subject(s)
Animals, Wild/psychology , Animals, Zoo/psychology , Behavior, Animal , Elephants/psychology , Walking/statistics & numerical data , Animal Welfare , Animals , Botswana , California , Female , Geographic Information Systems , Male , Obesity/prevention & control , Obesity/veterinary , Sex Distribution , Time
12.
Clin Chim Acta ; 433: 62-8, 2014 Jun 10.
Article in English | MEDLINE | ID: mdl-24631133

ABSTRACT

Falsely elevated concentrations of immunosuppressants can be caused by reversible adsorption to central venous catheter (CVC) systems. If undetected, this may lead to dose reduction resulting in underdosage which may even entail graft-versus-host disease or organ rejection. We analyzed the adsorption and release for cyclosporine A (CsA) and tacrolimus (Tac) in vitro and in vivo. Four types of CVCs were examined in vitro: two made from polyurethane (PU), one from silicone and one from PU with an incorporated silver ion-based antimicrobial agent. All 26 CVCs analyzed in vitro showed significant reversible adsorption of CsA (n=13; p=0.001) and Tac (n=13; p=0.001, Wilcoxon signed rank test). Immediately after infusing the drugs, the mean concentrations of 6420ng/mL of CsA and 250ng/mL of Tac were measured. Flushing with NaCl lowered the drug release. Besides, blood samples of fifteen patients were taken simultaneously from all lumina of the CVC and via venipuncture. The samples from contaminated lumina showed the mean elevations by a factor of 11 for CsA (n=12) and 89 for Tac (n=3). Blood sampling for immunosuppressant monitoring should thus never be performed from lumina previously used for infusing the drug even after prolonged periods of time and extensive rinsing.


Subject(s)
Blood Chemical Analysis , Central Venous Catheters , Cyclosporine/blood , Cyclosporine/chemistry , Tacrolimus/blood , Tacrolimus/chemistry , Adsorption , Adult , Aged , Edetic Acid/chemistry , False Positive Reactions , Fats/chemistry , Humans , Immunosuppressive Agents/blood , Immunosuppressive Agents/chemistry , Middle Aged , Stem Cell Transplantation , Time Factors , Water/chemistry , Young Adult
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