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1.
The list of the actions spent in the summer of 2005 in territory of the Tyumen region, in connection with a destruction of wild birds and poultry from the avian flu is submitted. Except for the quarantine and other sanitary-epidemic measures warning drift of a avian influenza virus in facilities, it is carried out of serological monitoring among workers of poultry-farming facilities and the population of the struck settlements on presence of antibodies to an influenza A (H5N1) virus. Taking into account ways of migration of a wild waterfowl in this territory, probability of contact to it and risk of infection of people, the conclusion about necessity of continuation the monitoring behind circulation of an avian influenza virus in region is made.  相似文献   

2.
Wildlife-related accidents are a serious problem in different countries and describing their temporal pattern allows for the development of measures to mitigate them. We described the temporal pattern of wild ungulate-related accidents occurring between January 2006 and December 2010 in the Autonomous Region of Galicia, northwest of Spain. We examined the temporal distribution of the accidents according to months, phenological and hunting seasons, days of the week and time of the day. From the 6,255 wild ungulate-related traffic accidents analysed, 36.5% were related to roe deer Capreolus capreolus and 62.8% were related to wild boar Sus scrofa. The monthly distribution of accidents was not random but follows a characteristic pattern for each species. Roe deer-related accidents have their maximum in April and May, coinciding with the breeding season, followed by July, coinciding with the rut. Wild boar-related accidents have their maximum between October and January, coinciding with the hunting season but also with months with the longest nights. Both roe deer- and wild boar-related accidents showed an increase at weekends, specially on Sundays. During the hunting season, the wild boar-related accidents showed a marked peak on the same day. This weekly pattern was explained by drivers’ behaviour and by hunting. For roe deer, peaks of accidents occurred between 19:00 and 22:00 (about dusk) and between 05:00 and 08:00 (about dawn). For wild boar, 69% of accidents occurred between 18:00 and 23:00, coinciding with dusk and night. This daily pattern of accidents was explained by the behaviour of the species.  相似文献   

3.
Infectious disease emergence represents a global threat to human, agricultural animal and wildlife health. West Nile virus (WNV) first emerged in the Americas in 1999 following its introduction to New York from the Old World. This flavivirus rapidly spread across much of North America, causing human, equine and avian mortalities and population declines of multiple wild bird species. It has now spread to Central and South America, and there is concern that the virus will reach the Galápagos Islands, a UNESCO World Heritage Site famous for its unique biodiversity, with potentially catastrophic results. Here, we use wild bird surveillance to examine the current WNV status in the Galapagos Islands and around the Ecuadorian city of Guayaquil (the main air and sea port serving Galápagos). We conducted serosurveys of wild birds on three Galápagos Islands (Baltra, San Cristobal and Santa Cruz) with direct transport links to the South American continent. In addition, dead birds killed by car collisions on Santa Cruz were tested for WNV infection. On mainland Ecuador, serosurveys of wild birds were conducted at three sites around Guayaquil. No evidence of WNV seropositivity or infection was detected. Although wider testing is recommended on the mainland, the study highlights a limit of WNV spread within South America. Our results indicate the continued absence of WNV on Galápagos and suggest the current likelihood of human-mediated transport of WNV to Galápagos to be low. The risk of emergence will almost certainly increase over time, however, and stringent biosecurity and surveillance measures should be put in place to minimise the risk of the introduction of WNV (and other alien pathogens) to Galápagos.  相似文献   

4.
Human and non-human animals tend to avoid risky prospects. If such patterns of economic choice are adaptive, risk preferences should reflect the typical decision-making environments faced by organisms. However, this approach has not been widely used to examine the risk sensitivity in closely related species with different ecologies. Here, we experimentally examined risk-sensitive behaviour in chimpanzees (Pan troglodytes) and bonobos (Pan paniscus), closely related species whose distinct ecologies are thought to be the major selective force shaping their unique behavioural repertoires. Because chimpanzees exploit riskier food sources in the wild, we predicted that they would exhibit greater tolerance for risk in choices about food. Results confirmed this prediction: chimpanzees significantly preferred the risky option, whereas bonobos preferred the fixed option. These results provide a relatively rare example of risk-prone behaviour in the context of gains and show how ecological pressures can sculpt economic decision making.  相似文献   

5.
转基因植物外源基因逃逸的途径   总被引:13,自引:0,他引:13  
随着转基因植物商品化进程的加快,对其进行生态风险性评价也日益引起许多学者和科学家的重视,人们对转基因逃逸到其它亲缘物种中能否产生超级杂草,昆虫是否会产生耐受性及转基因植物对生物多样性的影响等问题进行了广泛的研究,本文对转基因植物外中源基因逃逸的几种主要途径作了综述,并对研究方法与手段进行了简要讨论,希望能为有关决策和科研部门提供一些思路。  相似文献   

6.
随着转基因植物商品化进程的加快,对其进行生态风险性评价也日益引起许多学者和科学家的重视。人们对转基因逃逸到其它亲缘物种中能否产生超级杂草、昆虫是否会产生耐受性及转基因植物对生物多样性的影响等问题进行了广泛的研究。本文对转基因植物中外源基因逃逸的几种主要途径作了综述,并对研究方法与手段进行了简要讨论,希望能为有关决策和科研部门提供一些思路。  相似文献   

7.
转基因作物与其野生亲缘种间的基因流   总被引:41,自引:0,他引:41  
随着基因工程技术的突飞猛进,许多主要的农作物经过遗传修饰获得了优良的性状,并被批准进入市场。在美国,到1996年5月为止,经政府批准商业化的转基因作物已有7种;而在欧共体,仅在1991~1994年被释放作大田试验的转基因植物就达291个[1]。对于转...  相似文献   

8.
There is compelling evidence about the manifest effects of inbreeding depression on individual fitness and populations' risk of extinction. The majority of studies addressing inbreeding depression on wild populations are generally based on indirect measures of inbreeding using neutral markers. However, the study of functional loci, such as genes of the major histocompatibility complex (MHC), is highly recommended. MHC genes constitute an essential component of the immune system of individuals, which is directly related to individual fitness and survival. In this study, we analyse heterozygosity fitness correlations of neutral and adaptive genetic variation (22 microsatellite loci and two loci of the MHC class II, respectively) with the age of recruitment and breeding success of a decimated and geographically isolated population of a long-lived territorial vulture. Our results indicate a negative correlation between neutral genetic diversity and age of recruitment, suggesting that inbreeding may be delaying reproduction. We also found a positive correlation between functional (MHC) genetic diversity and breeding success, together with a specific positive effect of the most frequent pair of cosegregating MHC alleles in the population. Globally, our findings demonstrate that genetic depauperation in small populations has a negative impact on the individual fitness, thus increasing the populations' extinction risk.  相似文献   

9.
湖南张家界市大鲵资源调查   总被引:4,自引:0,他引:4  
为科学确定张家界大鲵国家级自然保护区境内大鲵Andrias davidianus资源状况,2006~2008年对该保护区大鲵资源的分布区域和数量进行了调查.结果表明,近年该保护区野生大鲵呈不连续点状分布,约为0.2万尾,资源量仍有衰退趋势,人工养殖资源量增加较大,约3.21万尾.需要加强野生大鲵保护管理,增加人工放流数量与效益,以逐步恢复野生大鲵资源,同时继续发展大鲵人工养殖,不断增加大鲵的资源总量.  相似文献   

10.
Knowledge about changes in behavioural traits related to wildness and tameness is for most mammals lacking, despite the increased trend of using domestic stock to re‐establish wild populations into historical ranges. To test for persistence of behavioural traits of wild reindeer (Rangifer tarandus L.) exposed to hunting, we sampled DNA, vigilance and flight responses in wild reindeer herds with varying domestic ancestry. Analyses of 14 DNA microsatellite loci revealed a dichotomous main genetic structure reflecting their native origin, with the Rondane reindeer genetically different from the others and with least differentiation towards the Hardangervidda reindeer. The genetic clustering of the reindeer in Norefjell‐Reinsjøfjell, Ottadalen and Forollhogna, together with domestic reindeer, supports a predominant domestic origin of these herds. Despite extensive hunting in all herds, the behavioural measures indicate increasing vigilance, alert and flight responses with increasing genetic dissimilarity with domestic herds. Vigilance frequency and time spent vigilant were higher in Rondane compared to Hardangervidda, which again were higher than herds with a domestic origin. We conclude that previous domestication has preserved a hard wired behavioural trait in some reindeer herds exhibiting less fright responses towards humans that extensive hunting has, but only slightly, altered. This brings novel and relevant knowledge to discussions about genetic diversity of wildlife in general and wild reindeer herds in Norway in specific.  相似文献   

11.
A comparative study of the genetic structure of natural and anthropogenic populations of G. soja gives significant information about formation of different populations, and allows developing measures for preservation of unique natural gene bank of wild soybean, the species closely related to cultivated soybean. In this study, ISSR markers were used to carry out a comparative analysis of genetic structure of natural and anthropogenic subpopulations of G. soja for studying possible mutual influence of subpopulations of anthropogenic and natural phytocenosis on the formation of their genetic diversity and to study genetic structure of natural subpopulations of wild soybean in the contact places between the two types ofcenoses. As a result, the characteristics that describe the genetic diversity of studied populations have been identified and the important role of an interaction between subpopulations of different phytocenoses on formation of the spatial genetic structure of population in the valley of Tsukanovka river has been demonstrated.  相似文献   

12.
A new epidemiological scenario involving the oral transmission of Chagas disease, mainly in the Amazon basin, requires innovative control measures. Geospatial analyses of the Trypanosoma cruzi transmission cycle in the wild mammals have been scarce. We applied interpolation and map algebra methods to evaluate mammalian fauna variables related to small wild mammals and the T. cruzi infection pattern in dogs to identify hotspot areas of transmission. We also evaluated the use of dogs as sentinels of epidemiological risk of Chagas disease. Dogs (n = 649) were examined by two parasitological and three distinct serological assays. kDNA amplification was performed in patent infections, although the infection was mainly sub-patent in dogs. The distribution of T. cruzi infection in dogs was not homogeneous, ranging from 11–89% in different localities. The interpolation method and map algebra were employed to test the associations between the lower richness in mammal species and the risk of exposure of dogs to T. cruzi infection. Geospatial analysis indicated that the reduction of the mammal fauna (richness and abundance) was associated with higher parasitemia in small wild mammals and higher exposure of dogs to infection. A Generalized Linear Model (GLM) demonstrated that species richness and positive hemocultures in wild mammals were associated with T. cruzi infection in dogs. Domestic canine infection rates differed significantly between areas with and without Chagas disease outbreaks (Chi-squared test). Geospatial analysis by interpolation and map algebra methods proved to be a powerful tool in the evaluation of areas of T. cruzi transmission. Dog infection was shown to not only be an efficient indicator of reduction of wild mammalian fauna richness but to also act as a signal for the presence of small wild mammals with high parasitemia. The lower richness of small mammal species is discussed as a risk factor for the re-emergence of Chagas disease.  相似文献   

13.
In south-central Spain, the harvest of Eurasian wild boar (Sus scrofa) has increased significantly during recent decades in association with more intensive management actions to increase hunting yields and with consequent effects on the health status of the wild boar populations. We investigated the spatio-temporal trends and the risk factors related to the prevalence of Trichinella spp. in wild boar in order to obtain the annual probability of occurrence for these parasites in the Ciudad Real province of south-central Spain. Based on muscle samples collected during the hunting seasons from 1998/1999 to 2009/2010, the mean prevalence for Trichinella spp. in 95,070 wild boar was 0.2% (95% confidence interval 0.17-0.23). A subsample of 1,432 wild boar was also tested by ELISA. No correlation was observed between the prevalence of infection detected by serology and by the artificial digestion of muscle. The presence of Trichinella infections in wild boar showed a decreasing trend during the study period and was negatively related with fenced wild boar populations. The predicted 'favourability' for Trichinella infections disappeared almost completely after the 2006/2007 hunting season. Risk maps based on biogeographical tools showed, however, that most hunting estates presented favourable risk factors for these parasites during at least one of the hunting seasons studied.  相似文献   

14.
Long-term and widespread monitoring programs are essential to understanding the role of human-dominated landscapes in supporting wild bee populations. Urbanization results in increased impervious surfaces throughout the landscape, fragmentation of green space, and a loss of naturally occurring floral vegetation. All of these changes have a negative impact on pollinator diversity. The objective of this study was to assess the abundance and richness of wild bee species throughout a small city in northwest Pennsylvania and identify how management of land throughout the city may influence bee communities. Seventeen sites across a land use gradient, moving from areas with large open spaces and mainly permeable surfaces, to sites in the city center consisting of mainly impermeable surfaces, were sampled over a 2-year period. During this time, 106 known species were identified with four state records and 1 undescribed species. Bee species richness was greatest at sites with the largest amount of permeable surface and naturally-occurring, native vegetation. Richness decreased on the college campus and city center where landscapes were highly managed and impermeable surfaces were most abundant. While floral richness was not related to bee abundance and richness, the number of open blooms near traps did have a positive impact on bee species richness. Overall, this survey revealed considerable richness never before recorded for northwest Pennsylvania, suggesting the importance of conservation management in homeowner and community yard space.  相似文献   

15.
To successfully reproduce, many carnivorous mammals need access to suitable den sites. Den site selection is often based on fitness related criteria like escape from predators, food availability and shelter from extreme weather conditions. African wild dogs are cooperative breeders that use a den to give birth to their offspring. They often co-exist with lions and spotted hyenas, both of which are known to kill African wild dog pups. Little is known about den site selection by African wild dogs. In this study, we compared vegetation characteristics and distribution of roads and waterholes around den sites and random sites, in areas with high and low lion and spotted hyena densities. In both areas, African wild dogs selected den sites in closed woodland with little visibility, which is likely to reduce detection by predators, increase the likelihood of escape when detected, and might provide shelter from extreme weather conditions. In the high predator density area, African wild dogs seemed to spatially avoid predators by selecting den sites in this type of habitat relatively further away from waterholes and roads. African wild dogs have high energetic costs of gestation. Therefore, even when predation risk is relatively low, they are likely to try to maximise their fitness by choosing a den site in habitat that will provide optimal protection for their offspring, leaving little additional options to respond to a higher predation pressure.  相似文献   

16.
We compared the diet of hatchery-reared steelhead produced from an integrated hatchery program as emigrating spring smolts and non-migrating hatchery residuals to their sympatric wild counterparts. Our results suggest that there is a potential for hatchery fish to affect wild steelhead populations due to dietary overlap and subyearling salmonid predation; however, relative ecological risk did not increase as steelhead delayed or forwent emigration. Predation by hatchery smolts was related to release timing, but not experience with native fish. Diet composition appears to be more strongly affected by seasonal and yearly differences in prey abundance and presence rather than differences in rearing environments. Hatchery and wild steelhead showed small but important foraging differences. Hatchery smolts did not consume as many salmonids as wild fish and hatchery residuals showed relatively stronger surface oriented feeding behavior than wild parr. Because most hatchery smolts emigrated shortly after release and the overall number of residuals in the study creek was low, we speculate that in this case there is low dietary and predatory-based risk of hatchery steelhead in Abernathy Creek negatively impacting wild salmonids.  相似文献   

17.
Hybridization between wild and captive-bred individuals is a serious conservation issue that requires measures to prevent negative effects. Such measures are, however, often considered controversial by the public, especially when concerning charismatic species. One of the threats to the critically endangered Fennoscandian arctic fox Alopex lagopus is hybridization with escaped farm foxes, conveying a risk of outbreeding depression through loss of local adaptations to the lemming cycle. In this study, we investigate the existence of escaped farm foxes among wild arctic foxes and whether hybridization has occurred in the wild. We analysed mitochondrial control region sequences and 10 microsatellite loci in samples from free-ranging foxes and compared them with reference samples of known farm foxes and true Fennoscandian arctic foxes. We identified the farm fox specific mitochondrial haplotype H9 in 25 out of 182 samples, 21 of which had been collected within or nearby the wild subpopulation on Hardangervidda in south-western Norway. Genetic analyses of museum specimens collected on Hardangervidda (1897–1975) suggested that farm fox genotypes have recently been introduced to the area. Principal component analysis as well as both model- and frequency-based analyses of microsatellite data imply that the free-ranging H9s were farm foxes rather than wild arctic foxes and that the entire Hardangervidda population consisted of farm foxes or putative hybrids. We strongly recommend removal of farm foxes and hybrids in the wild to prevent genetic pollution of the remaining wild subpopulations of threatened arctic foxes.  相似文献   

18.
This study explores the relations between captive and noncaptive (literature-reported wild) adult weights in 53 anthropoid primate species. Based on recent studies of variation in growth among wild populations, it is expected that captive and wild weights are highly correlated. In addition, the lack of a relation between species size and captive and wild weights is anticipated. Differences between wild and captive weights are investigated. Correlations between captive and wild weights are high. Within groups of closely related species, correlations can be expected to average r = .95 for both males and females. At low taxonomic levels (within genera), correlations are not generally as high. However, captive and noncaptive intrageneric correlations are comparable to intrageneric correlations based solely on wild weights reported by different literature sources. Size appears to be unrelated to differences in captive and wild weights. Species that appear to be at elevated risk of obesity are identified. This analysis finds that deviations between captive and wild weights are positively related to growth duration (measured for captive primates). This finding implies that, in long-growing species, wild weights may underestimate asymptotic size. Hypotheses explaining this phenomenon are developed. In general, extensive overlap in weight between samples of captive and wild primates is documented. © 1994 Wiley-Liss, Inc.  相似文献   

19.
湖北省神农架林区野猪分布与传播非洲猪瘟风险分析   总被引:1,自引:0,他引:1  
野猪是非洲猪瘟(ASF)传播的重要媒介,神农架林区野猪种群数量高、分布广,调查野猪分布对ASF防控有着重要意义.本研究首先通过布设红外相机117台、样线287条调查神农架林区野猪实体和痕迹位点后,应用最大熵模型预测林区野猪分布,再根据野猪、居民区、交通要道的空间分布数据,应用核密度估计法分析神农架林区各地野猪传播ASF...  相似文献   

20.
Personality affects many aspects of an individual's behaviour, life history and fitness, and has been shown to be moderately heritable in wild populations. Correlations between personality and risk‐taking that lead to life history tradeoffs could act to maintain variation in personality within a population, but this has not yet been tested. In this study, we used females from a marked population of North American red squirrels in Kluane, Yukon, to determine whether personality predicts risk‐taking in the wild, and whether these risk‐taking behaviours result in life history tradeoffs. We measured personality in open field and mirror image stimulation tests and extracted two traits, activity and aggressiveness, using principal component analysis and mixed model techniques. Using trapping records for individuals from February to September 2005, we obtained three measures of risk‐taking: the number of trapping events, the number of different trapping locations, and the maximum distance between the home territory and a trapping event. We used GLMs to determine whether the activity and aggressiveness of individuals are related to these risk‐taking behaviours, and found that active squirrels were trapped significantly more frequently and at a greater number of locations. There was also a significant interaction between activity and aggressiveness to affect the maximum capture distance. To determine if there are fitness tradeoffs associated with these risk‐taking behaviours, we examined female bequeathal behaviour and survival. Bequeathing a territory increases offspring probability of overwinter survival, and we found that an increasing number of trapping locations was associated with an increasing tendency to bequeath. Active females were less likely to survive until the following spring. Risk‐taking is therefore predicted by personality in this population, and they affect both survival and territorial bequeathal. These fitness tradeoffs may therefore lead to the maintenance of variation in personality.  相似文献   

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