首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
    
ABSTRACT Little information on foraging habitats of sympatric species of skunks in Texas, USA, is available. We compared 11 western spotted skunks (Spilogale gracilis) and 10 striped skunks (Mephitis mephitis) using radiotelemetry data to assess habitat use during foraging at broad levels of selection in a fragmented habitat. Western spotted skunks used areas with more large mesquite (Prosopis glandulosa) trees than did striped skunks and randomly selected points. Striped skunk habitat use was not different from randomly chosen locations. Contrary to previous research, both species appear to avoid agricultural habitat. A habitat management plan may be difficult to implement for striped skunks in Texas because they did not favor any available habitat. Conservation of western spotted skunks in west-central Texas should focus on areas with older mesquite trees, areas that are now often brush controlled for management of livestock.  相似文献   

2.
    
The eastern spotted skunk (Spilogale putorius) is a species of conservation concern in much of its range and has experienced a decline since the early to mid-1990s. But the subspecies that inhabits peninsular Florida, the Florida spotted skunk (S. p. ambarvalis), might still be abundant and is an important nest predator of the endangered Florida grasshopper sparrow (Ammodramus savannarum floridanus). To gain insight on this little-studied subspecies and inform potential management strategies, we conducted a resource selection study on the Florida spotted skunk. We examined 5 hypotheses for den site selection related to den type, vegetation, and landscape characteristics in a dry prairie ecosystem in central Florida. We tracked 36 individual skunks to 757 den sites. Using discrete choice analysis, we found that male and nonbreeding female skunks at our study site were 5 times more likely to select a mammal burrow over a gopher tortoise (Gopherus polyphemus) burrow, that selection of a den site increased 34% for each 1-burrow increase in the number of nearby burrows, and that selection of a den site increased 3% for every 10-cm increase in a visual obstruction index. Similarly, breeding female skunks were more likely to select mammal burrows and shallow depressions over gopher tortoise burrows by 16-fold and 13-fold, respectively, and selection of a den site increased by 75% for every 1-burrow increase in the number of nearby burrows. In contrast to previous studies that occurred in forested, mountainous environments elsewhere in the species' range, our findings suggest that den characteristics might be more important than landscape or vegetation characteristics to Florida spotted skunk den site selection in dry prairie. Additionally, the frequency of prescribed fires on the landscape did not appear to affect Florida spotted skunk den site selection. Thus, Florida spotted skunks in this ecosystem might be landscape generalists, thereby potentially limiting the ability of managers to control nest predation by this subspecies through habitat management. © 2019 The Wildlife Society.  相似文献   

3.
4.
We report 10 polymorphic microsatellite loci primers developed for striped skunks (Mephitis mephitis), a widespread mesocarnivore in North America. Numbers of alleles in these loci ranged from seven to 14 and the observed heterozygosity ranged from 0.76 to 1.0. These primers will be useful for studying population dynamics of skunks where rabies is endemic and will be useful to estimate genetic relatedness among females sharing winter dens. Most of these primers amplify across species within the Mephitidae.  相似文献   

5.
6.
    
The eastern spotted skunk (Spilogale putorius) is a poorly understood mesocarnivore species that suffered a range-wide decline in the mid-1900s. Little is known about its current distribution or habitat needs, and in the southern Appalachians, where the Carolinas and Georgia converge, eastern spotted skunks were only recently discovered to persist. From January–April in 2016 and 2017, we used camera trap surveys to monitor eastern spotted skunks and used occupancy modeling to evaluate factors we hypothesized would influence the probability of spotted skunk detection and occurrence at the landscape scale. We detected spotted skunks at 55.6% of our sites and on 18.5% of sampling occasions. Our results suggest that detection probability was influenced by predation risk, camera setup, and the type of scent-based attractant used. Eastern spotted skunk occupancy probability had a negative relationship with elevation, such that the probability of occupancy on average increased 7% for every 100-m decrease in elevation. These results differ from previous findings from the northern Appalachian region, and suggest spotted skunks in the southern Appalachians may be more widely distributed than previously thought. To inform management, there remains a critical need for finer-scale investigations into resource selection and demographic trends. © 2019 The Wildlife Society.  相似文献   

7.
    
ABSTRACT Since the 1940s, eastern spotted skunks (Spilogale putorius) have declined dramatically throughout the Midwest. One hypothesis for the decline is the loss of suitable habitat, although little is known about the ecological requirements of this species. To elucidate seasonal home range and habitat selection by eastern spotted skunks, we conducted telemetry-based field work in the Ouachita Mountains of western Arkansas, USA. During 2 years of field work, we collected day- and nighttime radiolocations for 33 eastern spotted skunks. We used kernel-based utilization distributions, volume of intersection indices, and weighted compositional analysis to evaluate seasonal home range dynamics and habitat selection. Although we found moderate adult male site fidelity, there were large seasonal differences in home range size, with ranges of between 76 ha and 175 ha (± 22–62 SE) during summer, fall, and winter, and home ranges of 866 ha (± 235 SE) during spring. Male home range increases in the spring were likely caused by questing behavior in search of reproductive females. Females maintained home ranges of 54 ha to 135 ha (± 7–30 SE) and moderate site fidelity during all seasons. During each season, we observed selection of young shortleaf pine (Pinus echinata) and hardwood stands over other available cover types, likely due to a preference for a dense, complex understory and a closed canopy overstory to reduce predation risk. Most habitats in the study region were managed for an herbaceous understory and an older, more open canopy, in part to benefit red-cockaded woodpecker (Picoides borealis) populations. Thus, if simultaneous management for these 2 vertebrates is a goal, a balance of early and late successional habitat should be reached.  相似文献   

8.
采用千米网格的方法,对黄河三角洲滨海湿地进行土壤采样和植被群落调查,利用MaxEnt模型和GIS空间分析技术,模拟该地区优势物种的潜在分布,定量分析优势物种的主导环境影响因子及其生态位参数.结果表明: 黄河三角洲滨海湿地的优势物种为柽柳、芦苇和盐地碱蓬.影响柽柳、芦苇和盐地碱蓬潜在分布的主导环境因子分别为硝态氮、盐分、坡度、镁、海拔和铵态氮,硝态氮、盐分、全磷、pH、海拔和铵态氮,硝态氮、盐分和铵态氮.黄河三角洲滨海湿地优势物种的存在概率与盐分呈正相关,与其他主导环境影响因子呈负相关.黄河三角洲滨海湿地优势物种的潜在核心适生区主要分布在滨海地区,芦苇的分布范围较柽柳和盐地碱蓬更广泛.  相似文献   

9.
10.
    
Knowledge of threatened species’ distributions is essential for effective conservation decision‐making. Species distribution models (SDMs) are widely used to map species’ geographic ranges, identify new areas of suitable habitat and guide field surveys. In New South Wales (NSW), Australia, there are grave doubts about whether populations of the critically endangered long‐footed potoroo (Potorous longipes) remain extant, and identification of occupied sites is a high priority for its conservation. We used an SDM (Maxent) to identify regions in NSW that may have suitable habitat for the potoroo. The SDM was built with seven climate layers and had strong predictive performance (cross‐validated AUC = 0.94). We then combined this information on habitat suitability with vegetation and topography, to identify 58 survey sites across NSW. From April 2016 to May 2017, we undertook six field trips deploying six to eight cameras at each site for 52–63 days, resulting in 25 120 camera trap nights. A total of 215 759 images captured 43 native and feral animal species, but no long‐footed potoroos. Following the survey, newly available, independent presence and absence data were used to validate our model. A Kruskal–Wallis H test indicated that habitat suitability values were significantly higher at presence locations than absence locations (H = 58.66, d.f. = 1, P < 0.001). Finally, we refitted the Maxent model with the new data and identified additional regions that future surveys could explore. We conclude, however, that if the long‐footed potoroo remains extant in NSW, it is extremely rare.  相似文献   

11.
罗玫  王昊  吕植 《生态学杂志》2017,28(12):4001-4006
物种分布模型是物种研究和保护者常用的工具.不同模型的预测结果可能相差很大,对研究者选择模型造成一定的难度.本研究使用大熊猫的实际分布数据评估了两种常见物种分布模型Biomod2和最大熵模型(MaxEnt)的表现,运用ROC曲线下面积(area under the curve,AUC)、真实技巧统计值(true skill statistics,TSS)、KAPPA统计量3种指标综合评估了两种模型预测结果的准确度.结果表明: 当使用的物种分布数据和模拟重复次数足够多的时候,两者都能够给出相当准确的预测.相对于MaxEnt,Biomod2的预测准确度更高,尤其是在物种分布点稀少的情况下.然而,Biomod2使用难度较大,运行时间较长,数据处理能力有限.研究者应基于对预测结果的误差要求来选择模型.在误差要求明确且两个模型都能满足误差要求时,建议使用MaxEnt,否则应优先考虑使用Biomod2.  相似文献   

12.
    
Contemporary landscapes are subject to a multitude of human‐derived stressors. Effects of such stressors are increasingly realized by population declines and large‐scale extirpation of taxa worldwide. Most notably, cumulative effects of climate and landscape change can limit species’ local adaptation and dispersal capabilities, thereby reducing realized niche space and range extent. Resolving the cumulative effects of multiple stressors on species persistence is a pressing challenge in ecology, especially for declining species. For example, wolverines (Gulo gulo L.) persist on only 40% of their historic North American range. While climate change has been shown to be a mechanism of range retractions, anthropogenic landscape disturbance has been recently implicated. We hypothesized these two interact to effect declines. We surveyed wolverine occurrence using camera trapping and genetic tagging at 104 sites at the wolverine range edge, spanning a 15,000 km2 gradient of climate, topographic, anthropogenic, and biotic variables. We used occupancy and generalized linear models to disentangle the factors explaining wolverine distribution. Persistent spring snow pack—expected to decrease with climate change—was a significant predictor, but so was anthropogenic landscape change. Canid mesocarnivores, which we hypothesize are competitors supported by anthropogenic landscape change, had comparatively weaker effect. Wolverine population declines and range shifts likely result from climate change and landscape change operating in tandem. We contend that similar results are likely for many species and that research that simultaneously examines climate change, landscape change, and the biotic landscape is warranted. Ecology research and species conservation plans that address these interactions are more likely to meet their objectives.  相似文献   

13.
华俊钦  石江艳  李建强  杨海  徐基良 《生态学报》2020,40(20):7287-7298
森林生态系统类型自然保护区是我国最主要的自然保护区类型,该类型自然保护区通常具有复杂多样的保护对象,因此对其进行功能区划需全面考虑各种保护对象的需求。评价森林生态系统类型的自然保护区功能区划有利于提高自然保护区的保护有效性。以属于森林生态系统类型自然保护区的河南连康山国家级自然保护区功能区划为研究对象,于2016年12月至2018年12月在该自然保护区内进行样线和红外相机调查,获取白冠长尾雉及与白冠长尾雉存在种间相互作用物种的分布点数据,结合收集的环境数据,采用MaxEnt模型对白冠长尾雉(Syrmaticus reevesii)和与白冠长尾雉存在种间相互作用物种的分布进行预测,进而分析物种与该自然保护区功能区划的空间关系,及自然保护区内野生动物分布与人为干扰强度的空间关系,评估连康山国家级自然保护区现有功能区划对白冠长尾雉和与白冠长尾雉存在种间相互作用物种的保护有效性。结果表明,保护区内高保护价值区域面积为33.84 km2,核心区、缓冲区和实验区内高保护价值区域面积分别占保护区总面积的18.96%、3.84%和9.19%,自然保护区内高保护价值区域面积比例偏低。保护区现有功能区划并不能充分满足保护白冠长尾雉栖息地的需要,且核心区、缓冲区和实验区面临不同程度的人为干扰的影响,这对保护区内重点保护对象的生存产生潜在威胁。因此,结合保护区内保护价值与人为干扰分布现状,针对白冠长尾雉及相关物种的受胁情况提出两种不同的保护区功能区划优化方案,在不降低连康山国家级自然保护区面积的前提下,提高核心保护区白冠长尾雉及相关物种适宜栖息地面积的比例,同时降低保护区内人为干扰强度。本研究可为该保护区保护白冠长尾雉提供决策依据,并为其他以野生动物为保护目标的保护区功能区划优化提供指导方法。  相似文献   

14.
Summary The ultrastructure of corpora lutea obtained during the preimplantation, implantation and early postimplantation periods has been studied in 20 western spotted skunks. Fine structure of granulosa lutein cells was correlated with progesterone levels. The corpus luteum of the prolonged (7 month) preimplantation period contained undifferentiated small granulosa cells and differentiated large granulosa lutein cells. The former ranged in size between 12 and 20 and the latter between 20 and 45 . The ratio of small and large cells was about equal in an animal 2 days prior to nidation whereas only few small cells and numerous large cells were observed in an animal estimated to be 8 to 12 hours from nidation. Occasionally small cells were observed amidst large ones during the 24 hour nidation period, i.e. adhesion of trophoblast with the luminal uterine epithelium, but small cells were absent in animals after this period. Small cells had some smooth and rough endoplasmic reticulum, rod-shaped mitochondria with platelike cristae, small Golgi complex, and relatively smooth plasma membranes. Large lutein cells had abundant smooth endoplasmic reticulum, membranous whorls of smooth endoplasmic reticulum, usually round mitochondria with tubular and lamellar cristae, a well developed Golgi complex, variable amounts of lipid droplets, and highly plicated and ruffled plasma membranes. Peripheral plasma progesterone levels during the prolonged preimplantation period ranged between 1.1 and 7.9 ng/ml, but during implantation it was between 8 and 16.6 ng/ml. It is suggested that plasma progesterone levels fluctuate during the time of implantation and should not be regarded as a basis to predict actual nidation in the western spotted skunk.This research was supported in part by Grant Number HD06556 from the National Institute of Child Health and Human Development.  相似文献   

15.
    
The green anole Anolis carolinensis invaded the Ogasawara Islands in Japan, drove various native species to extinction, and its distribution expanded 14 years after initial establishment. A. carolinensis invaded Okinawa Island, but it has not expanded its distribution in more than 25 years, although its density is extremely high in the southern region. To determine whether A. carolinensis has the potential to expand its distribution on Okinawa Island, we performed phylogenetic analysis of mitochondrial ND2 DNA sequences to study the origin of A. carolinensis that invaded Okinawa Island. We further used a species distribution model (MaxEnt) based on the distribution of native populations in North America to identify ecologically suitable areas on Okinawa Island. Nucleotide sequence analysis shows that the invader A. carolinensis originated in the western part of the Gulf Coast and inland areas of the United States and that a portion of the anoles on Okinawa was not introduced via the Ogasawara Islands. The MaxEnt predictions indicate that most areas in Okinawa Island are suitable for A. carolinensis. Therefore, A. carolinensis may have the potential to expand its distribution in Okinawa Island. The predictions indicate that habitat suitability is high in areas of high annual mean temperature and urbanized areas. The values of precipitation in summer in the northern region of Okinawa Island were higher compared with those of North America, which reduced the habitat suitability in Okinawa Island. Adaptation to low temperatures, an increase in the mean temperature through global warming, and an increase in open environments through land development will likely expand the distribution of A. carolinensis in Okinawa Island. Therefore, we must continue to monitor the introduced populations and be alert to the possibility that city planning that increases open environments may cause their range to expand.  相似文献   

16.
食物资源是灵长类动物栖息地选择的重要因素,了解海南长臂猿食物资源的分布对海南长臂猿栖息地保护和恢复具有重要意义。基于研究区180块样地,获得了海南长臂猿105种食用树种分布数据,采用MaxEnt模型对6种果实食用树种进行了空间分布预测,并探讨了不同果实类型树种与气候、地形等环境因子的相关关系。结果表明:6种果实类型的模型检验结果AUC值均超过0.90,模拟精度较高;8月降水量在浆果、榕果和坚果类树种中的贡献率为43.8%、27.8%和19.6%,哈格里夫斯参考蒸发量在核果、球果和聚花果类树种的贡献率为23.6%、51.1%和58.8%,最冷月平均温度在6种果实类型贡献率均超过12%;果实类型发生概率随最冷月最低温度、哈格里夫斯参考蒸发量呈单调递减趋势;果实类型集中分布区主要在斧头岭、黑岭、雅加大岭一带,面积达2392.19 hm~2,其中2346.88 hm~2位于保护区内,比例达98.11%,表明保护区有效保护了不同果实类型的食用树种。本研究可为海南长臂猿栖息地保护和植被恢复提供参考。  相似文献   

17.
兰属(Cymbidium)中,除了兔耳兰C.lancifolium以外的所有种均被列为国家重点保护野生植物。为探究其在未来气候条件下的潜在分布格局,该研究基于兰属植物已知的分布点和19个气候因子,利用最大熵(MaxEnt)模型和地理信息系统(ArcGIS)模拟兰属以及其中20种兰属植物在9种不同气候情景(当代以及未来2030s、2050s、2070s和2090s 4个时间段各两种温室气体排放情景)下的潜在分布格局。结果表明:(1)最干旱季降水量(Bio17)、年降水量(Bio12)和温度季节性变化(Bio4)是影响兰属植物地理分布格局的主导气候因子。(2)不同兰属植物在未来情景下的适生区表现出不同的变化趋势,并且影响其分布的主导气候因子也有所不同。其中,冬凤兰(C.dayanum)等8个物种的适生区面积整体呈扩张趋势,而西藏虎头兰(C.tracyanum)等12个物种的适生区面积整体则呈缩减趋势。该研究结果为兰属植物就地保护与迁地保护提供了重要参考,对兰属等濒危野生植物的保护具有积极意义。  相似文献   

18.
兰属(Cymbidium)中,除了兔耳兰C. lancifolium以外的所有种均被列为国家重点保护野生植物。为探究其在未来气候条件下的潜在分布格局,该研究基于兰属植物已知的分布点和19个气候因子,利用最大熵(MaxEnt)模型和地理信息系统(ArcGIS)模拟兰属以及其中20种兰属植物在9种不同气候情景(当代以及未来2030s、2050s、2070s和2090s 4个时间段各两种温室气体排放情景)下的潜在分布格局。结果表明:(1)最干旱季降水量(Bio17)、年降水量(Bio12)和温度季节性变化(Bio4)是影响兰属植物地理分布格局的主导气候因子。(2)不同兰属植物在未来情景下的适生区表现出不同的变化趋势,并且影响其分布的主导气候因子也有所不同。其中,冬凤兰(C. dayanum)等8个物种的适生区面积整体呈扩张趋势,而西藏虎头兰(C. tracyanum)等12个物种的适生区面积整体则呈缩减趋势。该研究结果为兰属植物就地保护与迁地保护提供了重要参考,对兰属等濒危野生植物的保护具有积极意义。  相似文献   

19.
    
《Ecohydrology》2017,10(1)
Species distribution models were developed to predict the spatial patterns of the species diversity and the genetic diversity of stream organisms using a distributed hydrological model. We derived annual metrics of water depth and flow velocity in rivers using a hydrological model covering an entire catchment in northeastern Japan. We acquired geospatial data throughout the catchment and the presence records of six taxa within the part of the catchment. Subsequently we derived habitat suitability indices (HSIs) for these taxa using a frequency analysis or the maximum‐entropy approach (MaxEnt) to predict three metrics of species diversity. The Shannon‐Wiener's diversity index based on MaxEnt (Shannon_MaxE) most effectively represented empirical taxon richness. Subsequently, by comparing Shannon_MaxE and empirical genetic diversity for the four species of stream insects, we evaluated species‐genetic diversity correlations (SGDCs). Of the four species, only one caddisfly species (Hydropsyche orientalis ) displayed significant positive SGDCs. The result reflects the broad habitat range of this taxon throughout the catchment and its poor dispersal ability, whereas the other three species lacked SGDCs and displayed either a strong dispersal potential (Stenopsyche marmorata and Ephemera japonica ) or a narrower habitat range within upstream domains (Hydropsyche albicephala ). Finally, we estimated the spatial distribution of genetic diversity of H. orientalis populations based on the calculated Shannon_MaxE using the positive SGDC. This framework is promising for projecting future biodiversity in the context of anthropogenic perturbations such as climate change.  相似文献   

20.
邓浩  纪力强 《生物多样性》2008,16(1):96-102
本研究设计并实现了一个基于地理信息系统(GIS)的仅用物种已知分布点数据预测物种潜在分布地的PSDS系统.在这一系统中,通过层次聚类算法对物种已知分布点数据进行处理,减少了异常值对预测结果的影响,从而解决了环境包络模型预测结果过于乐观的问题,在物种已知分布数据较少时也能取得较好的结果.该系统实现了数据加载与导出、图层浏览与显示、生态因子分析与分布地预测、结果展示等功能,操作方便,简单易用.本文以白冠长尾雉(Syrmaticus reevesii)为例,根据4个省的少量已知分布点数据对其在国内的潜在分布地进行了预测,获得了较理想的结果,可为该物种的保护提供科学依据.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号