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51.
生境分析对物种保护具有重要的意义。笔者运用Maxent模型分析了48个华北豹地理分布点位和环境变量数据,对山西铁桥山省级自然保护区华北豹生境适宜性进行了评价。结果表明,华北豹生境选择的主要影响因子为:距村庄距离、坡度、距河流距离;生境适宜区主要分布在保护区西部,占总面积的45%. 相似文献
52.
ROBERT M. KIRBERGER DEWALD F. KEET WENCKE M. WAGNER 《Veterinary radiology & ultrasound》2006,47(2):145-152
Thoracic and pelvic limbs from 15 euthanized free-ranging lions (Panthera leo), ranging in age from 16 to 144 months, underwent standard radiographic evaluation. All lions had tested positive for Mycobacterium bovis by means of a modified intradermal tuberculn test. The radiographs of six lions were normal and nine had incidental findings of which six had more than one lesion. Seven lions had lesions suspected to be associated with tuberculosis, which was confirmed in specific joints in two lions. Incidental pathology was classified as traumatic injuries and degenerative or trauma-associated joint disease. The traumatic lesions were fractures of which the most remarkable was a femur malunion. Four lions had fibula and another three lions had metacarpal/tarsal and phalangeal fractures. Joint lesions included glenoid, humeral head, and accessory carpal bone osteophytes. There was evidence of a cranial cruciate ligament rupture in an 8-year-old male. Trauma induced joint lesions were seen in four stifles (fragmented or displaced sesamoid bones, fragmented meniscal ossicle, or mineralized fragments). Radiological abnormalities believed to be caused by M. bovis were present in one stifle, one radiocarpal three tibiotarsal, and one tarsometatarsal joints. These had evidence of septic arthritis with extensive bone formation and capsular mineralization. In one 20-month-old lion, changes typical of a bone abscess were found in a proximal tibia. Radiologic evidence of elbow hygromas were seen in three elbows, all believed to be caused by M. bovis. Lions appeared to cope fairly well with a variety of traumatic injuries and were also susceptible to some of the aging/incidental radiologic findings seen in dogs and cats. The suspected M. bovis osseous lesions were more likely to involve the joints, particularly the tarsal joint and were mainly proliferative. 相似文献
53.
Chunmei SHI Jing XU Nathan James ROBERTS Dan LIU Guangshun JIANG 《Integrative zoology》2023,18(1):157-168
The development of facial recognition technology has become an increasingly powerful tool in wild animal individual recognition. In this paper, we develop an automatic detection and recognition method with the combinations of body features of big cats based on the deep convolutional neural network (CNN). We collected dataset including 12 244 images from 47 individual Amur tigers (Panthera tigris altaica) at the Siberian Tiger Park by mobile phones and digital camera and 1940 images and videos of 12 individual wild Amur leopard (Panthera pardus orientalis) by infrared cameras. First, the single shot multibox detector algorithm is used to perform the automatic detection process of feature regions in each image. For the different feature regions of the image, like face stripe or spots, CNNs and multi-layer perceptron models were applied to automatically identify tiger and leopard individuals, independently. Our results show that the identification accuracy of Amur tiger can reach up to 93.27% for face front, 93.33% for right body stripe, and 93.46% for left body stripe. Furthermore, the combination of right face, left body stripe, and right body stripe achieves the highest accuracy rate, up to 95.55%. Consequently, the combination of different body parts can improve the individual identification accuracy. However, it is not the higher the number of body parts, the higher the accuracy rate. The combination model with 3 body parts has the highest accuracy. The identification accuracy of Amur leopard can reach up to 86.90% for face front, 89.13% for left body spots, and 88.33% for right body spots. The accuracy of different body parts combination is lower than the independent part. For wild Amur leopard, the combination of face with body spot part is not helpful for the improvement of identification accuracy. The most effective identification part is still the independent left or right body spot part. It can be applied in long-term monitoring of big cats, including big data analysis for animal behavior, and be helpful for the individual identification of other wildlife species. 相似文献
54.
[目的]研究东北虎在非繁殖期和发情交配期活动节律的差异,以及其活动节律之间是否存在性别差异。[方法]采用行为取样法对7只(3雌4雄)东北虎的发情交配期和非繁殖期进行了观察。[结果]东北虎发情交配期的主要行为包括休息、运动和发情交配,其中雌虎在发情交配期和非繁殖期休息和运动时间差别不大,而雄虎发情交配期的休息时间较非繁殖期明显下降,运动差异不明显;雌雄虎在非繁殖期和发情交配期的休息、运动和发情交配时间没有明显的性别差异。[结论]结果为优化东北虎的管理及提高其繁殖成功率提供了参考。 相似文献
55.
Andrey D. POYARKOV Bariushaa MUNKHTSOG Miroslav P. KORABLEV Alexander N. KUKSIN Dmitry Y. ALEXANDROV Maria D. CHISTOPOLOVA Jose Antonio HERNANDEZ‐BLANCO Ochirjav MUNKHTOGTOKH Alexander S. KARNAUKHOV Namdag LKHAMSUREN Munkhtsog BAYARAA Rodney M. JACKSON Aishwarya MAHESHWARI Viatcheslav V. ROZHNOV 《Integrative zoology》2020,15(3):224-231
The existence of a trans‐boundary population of the snow leopard (Panthera uncia) that inhabits the massifs of Tsagaanshuvuut (Mongolia) – Tsagan‐Shibetu (Russia) was determined through non‐invasive genetic analysis of scat samples and by studying the structure of territory use by a collared female individual. The genetic analysis included species identification of samples through sequencing of a fragment of the cytochrome b gene and individual identification using a panel of 8 microsatellites. The home range of a female snow leopard marked with a satellite Global Positioning System (GPS) collar was represented by the minimum convex polygon method (MCP) 100, the MCP 95 method and the fixed kernel 95 method. The results revealed insignificant genetic differentiation between snow leopards that inhabit both massifs (minimal fixation index [FST]), and the data testify to the unity of the cross‐border group. Moreover, 5 common individuals were identified from Mongolian and Russian territories. This finding clearly shows that their home range includes territories of both countries. In addition, regular movement of a collared snow leopard in Mongolia and Russia confirmed the existence of a cross‐border snow leopard group. These data support that trans‐boundary conservation is important for snow leopards in both countries. We conclude that it is crucial for Russia to study the northern range of snow leopards in Asia. 相似文献
56.
The jaguar (Panthera onca) is the largest feline in the Americas and third largest world-wide, smaller in size only to the tiger (P. tigris) and lion (P. leo). Yet, in comparison, relatively few studies on jaguar population densities have been conducted and baseline data for management purposes are needed. Camera trapping and capture-recapture sampling methods were used to estimate the size of a jaguar population in the Pantanal’s open wet grassland habitat, an important area for the long-term survival of the species. This study is the first jaguar population estimate conducted in co-operation with a GPS-telemetry study providing an important opportunity for comparing different methods of density estimation. An accessible area within a 460 km2 privately-owned ranch was sampled with equal effort during the dry seasons of 2003 and 2004. Thirty-one and twenty-five individual jaguars were identified in 2003 and 2004, respectively. Estimates of jaguar abundance were generated by program CAPTURE. Density estimates were produced according to different methods used to calculate the effectively sampled areas which ranged from 274 to 568 km2. For 2003, the currently-used mean maximum distance moved (MMDM) method produced a density of 10.3 jaguars/100 km2, while GPS-telemetry-based calculations produced a mean density of 6.6 jaguars/100 km2. For 2004, the MMDM method produced an estimate of 11.7 jaguars/100 km2 while GPS-telemetry calculations produced a density of 6.7 jaguars/100 km2. Our results suggest that the widely-used MMDM method used to calculate effectively sampled areas is significantly under-reflecting maximum distances moved by jaguars and their range-use and, thereby, considerably inflating cat density estimates. This overestimation could place a population in a difficult situation by lengthening the time taken to initiate protection measures because of underestimating the risk to that population. 相似文献
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58.
As one of five survived tiger subspecies, the South-China tiger (Panthera tigris amoyensis) specially disperses in China. This paper dedicated distribution and quantity of wild South-China tiger, and also introduced
distribution, quantity and pedigree of captive South-China tiger. In the middle of this century, about several thousands South-China
tiger distributed in following provinces, such as Hunan, Jiangxi, Guizhou, Fujian, Guangdong, Guangxi, Zhejiang, Hubei, Sichuan,
Henan, Shanxi, Shanxi, Gansu. etc. Until now, there are only about 20–30 wild South-China tigers distributing in the provinces
of Guangdong, Fujian, Jiangxi, and Hunan, Sichuan, and 50 captive South-China tiger are raised in zoos of China.
This subject is supported by Department of Wildlife and Forest Plant Conservation, Ministry of Forestry
(Responsible Editor: Zhu Hong) 相似文献
59.
Rahel Sollmann Mariana Malzoni Furtado Beth Gardner Heribert Hofer Anah T.A. Jácomo Natália Mundim Tôrres Leandro Silveira 《Biological conservation》2011,(3):1017-1024
Owing to habitat conversion and conflict with humans, many carnivores are of conservation concern. Because of their elusive nature, camera trapping is a standard tool for studying carnivores. In many vertebrates, sex-specific differences in movements – and therefore detection by cameras – are likely. We used camera trapping data and spatially explicit sex-specific capture–recapture models to estimate jaguar density in Emas National Park in the central Brazilian Cerrado grassland, an ecological hotspot of international importance. Our spatially explicit model considered differences in movements and trap encounter rate between genders and the location of camera traps (on/off road). We compared results with estimates from a sex-specific non-spatial capture–recapture model. The spatial model estimated a density of 0.29 jaguars 100 km−2 and showed that males moved larger distances and had higher trap encounter rates than females. Encounter rates with off-road traps were one tenth of those for on-road traps. In the non-spatial model, males had a higher capture probability than females; density was estimated at 0.62 individuals 100 km−2. The non-spatial model likely overestimated density because it did not adequately account for animal movements. The spatial model probably underestimated density because it assumed a uniform distribution of jaguars within and outside the reserve. Overall, the spatial model is preferable because it explicitly considers animal movements and allows incorporating site-specific and individual covariates. With both methods, jaguar density was lower than reported from most other study sites. For rare species such as grassland jaguars, spatially explicit capture–recapture models present an important advance for informed conservation planning. 相似文献
60.
All the fish used in this investigation were caught by commercial side trawlers along the eastern Cape coast of South Africa. Age and growth of P. laniarius was determined from otoliths collected monthly from April 1974 to September 1975. The validity of annuli was proved by monthly edge examination of the otoliths. There is no difference in growth between the sexes. The Von Bertalanffy equation Lt = 48,1 (l-e-0,10(e + 0.22)) was found to describe the growth of the panga in length. Some fish become sexually mature at a total length of 26 cm. Fifty percent maturity is attained at a length of 28 cm, between the ages of 4 and 5 years. All fish are sexually mature at a total length of 32 cm, at an age of 6 years. The spawning season of the panga extends from mid-September to May. 相似文献