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1.
The purpose of this field study has been to assess major changes in rhesus monkey populations of north central India over a period of 28 yrs from 1959 to 1986. Population censuses have been done in Aligarh District three times per year, and extensive regional surveys were done in 1959–1960, 1964–1965, 1977–1978, and 1985–1986. Throughout the 1960s and 1970s, rhesus populations in India declined more than 90%, from an estimated 2 million animals in 1960 to approximately 180,000 by 1980. These declines were attributed to increasing agricultural pressures in India, loss of primate habitats, less protection for monkeys, and high levels of trapping. In the 1970s, as India's agricultural production rose and stronger wildlife conservation programs developed, local populations of rhesus began to increase. These increases became more prominent after 1978, when India imposed a ban on export of monkeys. By 1985 a population in Aligarh District had returned to its 1960 level in total population size, although the number of groups remained low. Other local populations showed even more striking growth and greatly exceeded former levels. Some areas of India, however, have shown no improvement in rhesus populations. Overall, extensive field surveys of rural habitats in 1985–1986 showed a 53% recovery in the number of rhesus groups, and a 129% recovery in total rhesus from their low points in 1977–1978. We estimate the rhesus population of India in 1985 in the vicinity of 410,000–460,000 individuals.  相似文献   

2.
A population of rhesus monkeys (Macaca mulatta) at the ancient site of Tughlaqabad on the southern outskirts of New Delhi, India, showed moderate growth throughout the 1960s and 1970s and very rapid growth in the last 4 years. Between July 1980 and July 1983, the population increased 79%, from two groups of 160 monkeys to five groups of 286 monkeys, an average annual increase of 21.4%. The natality of the population has been high, averaging 82.4% over three birth seasons. Mortality and disappearance rates, especially of juveniles and adults, have been remarkably low with total annual mortality averaging only 3.7% from 1980 to 1983. We believe the striking record of population growth in this population can be attributed to total protection, abundant food, good cover, a lack of predators, a generally improving habitat, and low disease. With the right combination of ecological and behavioral factors, rhesus populations can double in four years. The Tughlaqabad population provides important guidelines for the restoration and conservation of primate populations.  相似文献   

3.
A population of rhesus macaques in the Taihang mountains on the Henan-Shanxi border is probably the northernmost population of the species. A more northerly population north of Beijing was locally extirpated in 1988. In the Taihang mountains, 26 natural groups, with >2000 monkeys, have been found. Six of them have been studied for 8 years. They live in a deciduous forest with temperate climate and cold snowy winters. The average group size is 82 individuals, and the population density is 3.1–7.2 individuals per km2. Home rangs are very large, varying from 11 to 22 km2. A natural reserve for the rhesus was established at Jiyuan in 1982, and one group, monitored and provisioned since 1984, has increased from 47 to 83 individuals, an increase of 76.5%.  相似文献   

4.
Rhesus monkeys (Macaca mulatta) at the Nanwan peninsula of Hainan Island, China, have been observed in the field for 25 years, and have been studied intensively for eight years, beginning in 1981. There were about 115 monkeys in 5 natural groups when the Nanwan Reserve was founded in 1965. From 1965 to 1984, the number of groups increased from 5 to 19, and the total population increased from 115 to 930 individuals, an annual population increase of 12.7%. From 1984 to 1987, the population continued a slower rate of increase (8.9%) to approximately 1200 monkeys in 20 groups. The home ranges of each monkey group at Nanwan varied from 0.16 to 0.72 km2, with a mean and standard deviation of 0.37 ± 0.18. The size of the home range of the rhesus was affected by the quality of vegetation and rhesus population density. The average birth rate per year was 77.8 ± 13.9%, varying from 53.8% to 100% since 1978. From 1978, the birth rates of two food provisioned groups were higher in alternate years (x? = 91.7%) and lower in intervening years (x? = 68.8%; P = <0.01). A minority (26.5%) of females have given birth at 4 years of age, most at 5 years. The sex ratio of newborns in any one year varied from 0.3 to 3.5 males to females, with a mean and standard error of 1.09 ± 0.37 males to females.  相似文献   

5.
The TRIM5α restriction factor can protect some species of monkeys, but not humans, from HIV infection. It has also emerged that some monkeys have a cyclophilin A domain retrotransposed into the TRIM5 locus resulting in the expression of a TRIMCyp protein with anti-retroviral activity. A high degree of sequence variation in the primate TRIM5 gene has been reported that varies between populations of rhesus macaques, a widely used non-human primate model of HIV/AIDS, and recently shown to correlate with susceptibility to simian immunodeficiency viruses in this species. Cynomolgus macaques are also used widely in HIV research. A non-indigenous population on Mauritius has highly restricted genetic diversity compared with macaques from Indonesia. The relative allelic diversity of TRIM5α and TRIMCyp within these two sub-populations may impact on the susceptibility of the macaques to simian immunodeficiency virus thereby influencing the outcome of studies using these monkeys. We sought to establish the genetic diversity of these alleles in cynomolgus macaques. We identified seven TRIM5α alleles in Indonesian macaques, three of which are novel, but only three in the Mauritian-origin macaques. Strikingly, 87% of Indonesian, but none of the Mauritian macaques, possessed a retrotransposed Cyp domain. A splice acceptor site single-nucleotide polymorphism that allows formation of a TRIMCyp protein was absent for the TRIM5α alleles found in the Mauritian macaques. The level of allelic diversity reported here is greater than previously proposed for cynomolgus macaque species.  相似文献   

6.
Five infant rhesus monkeys reared togather in free-ranging natural environment for about eight months were subjected to peer separation. Separation of an infant was inflicted by way of removing all the other infants from their home range. The infants so separated showed exceedingly high levels of locomotion and vocalizations in the beginning of separation phase, but their such excited behaviour did not last for more than a day, and during the remaining separation period they appeared to be quite depressed as mainly indicated by their reduced range of locomotion, reduced motivation for food and water, and reduced level of vocalization and environmental exploration. Thus, the animals showed a biphasic response to separation, which was characterized by an initial phase of ‘protest’ followed by a ‘despair’ stage, basically similar to what has been reported in infant rhesus monkeys subjected to peer or mother separation under laboratory conditions. The main project of which this research was a part is being financed by Indian Council of Social Science Research (ICSSR).  相似文献   

7.
Lao leaf monkeys (Trachypithecus (francoisi) laotum) are endemic to a small area of central and, marginally, north Lao. They are known from a few, mostly vague, historical records. We here present a detailed examination of the distribution of this little-known taxon and discuss its conservation status. Surveys since 1992 show its range to be centered upon the karst-dominated Phou Hin Poun National Protected Area (NPA), Nam Sanam Provincial Protected Area, and the southern part of Nam Kading NPA. The known range encompasses <2000 km2, within which occurrence is patchy, reflecting habitat availability. The taxonomic identity of leaf monkeys plausibly of this group reported to the north of this area is not known. In the south of Phou Hin Poun NPA, village reports that the monkeys have black heads are corroborated by the few sightings; their taxonomic relationship with typical Trachypithecus laotum is unknown. In the mid–late 1990s large populations remained and individuals were easily seen. There is no apparent large-scale threat to their habitat. There has been no significant reassessment of status since the late 1990s, nor is there any active conservation action in place. Although the monkeys are to a significant extent protected by the arduous terrain, this cannot be relied upon indefinitely: Trade-directed hunting, although apparently limited in the 1990s, is a potential threat that could cause rapid population declines. Local traditions offer significant starting points for conserving these monkeys.  相似文献   

8.
This study attempted to describe the pattern of social affiliations in a colony of free-ranging rhesus monkeys (Macaca mulatta) on Key Lois Island, Florida. Monkeys arrived to Key Lois in nine distinct groups that were held in a 50×100 ft enclosure for between 30 and 60 days and then released. The data consisted of observations of groups of monkeys seen together at various times in various locations. The study tested the hypothesis that monkeys that were in the same quarantine group would more frequently be seen together in the free-range than monkeys from different quarantine groups. The hypothesis was confirmed in seven of the nine groups. Chi-square =2137.1 (p<.001),Cohen’s kappa =.38 (p<.001) (1960). Prior common group membership was found to be predictive of future social affiliations. Explanations of residual kin structure from India, the effect of a primary social experience in a new environment, and the possibility of in-group versus out-group forces between the successively introduced groups were advanced as possible reasons for the findings.  相似文献   

9.
This article presents the distribution and status of bustards, which are listed as first-category protected animals according to the survey results during 1990–2002 in China. The Chinese populations of Otis tarda dybowskii are breeding in south-west of Heilongjiang Province, western Jilin Province, east and middle Inner Mongolia, north Ningxia Hui Autonomous Region, and Gansu Province. A few can winter in the south breeding-range. Its winter-range lies from the south to the Yellow River, as far as to Guizhou Province and Jiangxi Province. Its population number is about 200–300 or 500–800. The Chinese populations of O. t. tarda are breeding in the north and west of Xinjiang. It is unclear about its winter-range, which is presumed to be in south Asia. Recently we found individuals wintering in Chabuchaer and west Xinjiang. The population number is about 2000–3000. The habitat in breeding range includes steppe, grassland, desert grassland, and farmland. The habitat in winter range is the beach of rivers and lakes, meadows, meadow-grassland, and wheatland. The Chinese populations of Chlamydotis undulata macqueeni are breeding in the fringe of the Jungar Basin, the banks of the Ulungur River, Balikun and south Turpan Basin in Xinjiang, west Inner Mongolia, and west Gansu. NortheastMulei in eastern Jungar Basin of Xinjiang is the main breeding-range in the world. The bird uses desert and desert grassland as its habitat. Its winter-range is west Asia and south Asia. Its population number is about 2000. The Chinese populations of Tetrax tetrax are breeding in north Xinjiang, and China is located on the east border of its breeding-range. Its habitat is grassland and semi-desert, and its winter-range lies in south Asia. Its population in China is very scarce. In addition, we analyzed the causes of their endangerment and put forward protection tactics of Chinese Bustards. __________ Translated from Arid Zone Research, 2007, 24(2): 179–186 [译自: 干旱区研究]  相似文献   

10.
To develop a microsatellite marker set applicable to genome-wide screening of cynomolgus monkeys (Macaca fascicularis), 148 microsatellite markers were selected from the human genome database. The polymorphisms and inheritance of PCR products were determined by screening twenty unrelated monkeys and by analysis of three families, respectively. As a result, 106 primers (72%) gave PCR products of the size expected for humans and rhesus monkeys. Among these products, polymorphism and single-gene inheritance in cynomolgus monkeys was observed for 66 markers (62%). The average number of alleles at the 66 polymorphic loci was 5.86 (range 2–10), and average heterozygosity was 0.63 (range 0.10–0.88). This is the first report of microsatellite markers for cynomolgus monkeys. Chromosomal mapping of these markers is now in progress.  相似文献   

11.
South‐East Asia has an exceptionally high diversity of snakes, with more than 250 snake species currently recorded from Thailand. This diversity likely reflects the diverse range of geographical and climatic conditions under which they live, but the evolutionary history and population genetics of many snake species in South‐East Asia have been little investigated in comparison with morphological studies. Here, we investigated genetic variation in the monocled cobra, Naja kaouthia, Lesson, 1831, across its distribution range in Thailand using mitochondrial DNA (cytochrome b, control region) for ~100 individuals and the nuclear DNA gene (C‐mos) for a small subset. Using population genetic and phylogenetic methods, we show high levels of genetic variation between regional populations of this non‐spitting cobra, including the north‐eastern, north‐central and southern regions, in addition to a population on Pha‐ngan Island, 150 km offshore from the southern peninsula. Moreover, inclusion of the north‐eastern population renders N. kaouthia paraphyletic in relation to other regional Naja species. The north‐eastern population is therefore probably specifically distinct. Given that these cobras are otherwise undifferentiated based on colour and general appearance to the “typical” cobra type of this region, they would represent a cryptic species. As has been shown in other animal groups from Thailand, it is likely that the geographical characteristics and/or tectonic alteration of these regions have facilitated high levels of population divergence of N. kaouthia in this region. Our study highlights the need for dense sampling of snake populations to reveal their systematics, plan conservation and facilitate anti‐snake venom development.  相似文献   

12.

Background  

Studied since the early 1940's, chromosomal polymorphisms in the deciduous woods species Drosophila robusta have been characterized by well-defined latitudinal, longitudinal, and elevational clines, but – until at least ten years ago – stable, local population frequencies. Recent biogeographical analyses indicate that D. robusta invaded North America from southeast Asia and has persisted in eastern temperate forests for at least 20–25 my without speciating. The abundant chromosome polymorphisms found across the range of D. robusta are thus likely to be relatively ancient, having accumulated over many well known climatic cycles in North America. Sufficient long-term data are now available such that we can now gauge the rate of these evolutionary changes in natural populations due to environmental change.  相似文献   

13.
Mitochondrial DNA, purified from 36 samples of 23 local populations which are widely distributed in Vietnam, Burma, and 10 provinces of China, has been analyzed to model the phylogeny of rhesus monkeys. The 20 local populations of China may represent nearly all major populations in China. Using 20 restriction endonucleases of 6-bp recognition, we observed a total of 50–61 sites in the various samples. By combining the cleavage patterns for each enzyme, the 36 samples were classified into 23 restriction types, each of which was found exclusively in the respective population from which samples were obtained. By combining the earlier study of Indian rheusus monkeys, phylogenetic trees, which have been constructed on the basis of genetic distance, indicate that rhesus monkeys in China, Vietnam, India, and Burma can be divided into seven groups. Integrating morphological and geographical data, we suggest that rhesus monkeys in China, Vietnam, and Burma may be classified into six subspecies—M. m. mulatta, M. m. brevicaudus, M. m. lasiotis, M. m. littoralis, M. m. vestita, and M. m. tcheliensis-and rhesus monkeys in India may be another valid subspecies.M. m. tcheliensis is the most endangered subspecies in China. Divergence among subspecies may have begun 0.9–1.6 Ma. The radiation of rhesus monkeys in China may have spread from the southwest toward the east. The taxonomic status of the Hainan monkey and the Taiwan monkey require further investigation.  相似文献   

14.
 Interleukin 16 (IL-16) is synthesized as a 67 000 M r precursor (pro-IL-16), but only a carboxy terminal part of 12 000–14 000 M r is secreted by CD8(+) lymphocytes. This lymphokine binds to CD4 and has been shown to induce migration, affect the activation state of T cells, and inhibit immunodeficiency virus replication. It has been suggested that CD8(+) cell-derived soluble factors play a pivotal role in protecting natural-host nonhuman primates from developing immunodeficiency following SIV infection. In a first attempt to address this question, we cloned and sequenced the IL-16 cDNA from different primates. Here we report the pro-IL-16 sequence from chimpanzees, African green monkeys (AGM), rhesus macaques, and cynomolgus macaques. In order to compare and analyze structural motifs possibly involved in processing, intracellular targeting, or secretion, we extended our study to the New World monkeys saimiri and aotus and to the mouse. Alignments of deduced amino acids reveal that the human protein shares 99% similarity to that of chimpanzees, approximately 95% to rhesus, cynomolgus and AGM, about 90% to aotus and saimiri, and 77.5% to the mouse. Phylogenetic analyses revealed the expected evolutionary groupings. Received: 27 August 1997 / Revised: 7 October 1997  相似文献   

15.
Previous studies have used home range size to predict a species’ vulnerability to forest fragmentation. Northern bearded saki monkeys (Chiropotes satanas chiropotes) are medium-bodied frugivores with large home ranges, but sometimes they reside in forest fragments that are smaller than the species’ characteristic home range size. Here we examine how travel and spatial patterns differ among groups living in forest fragments of 3 size classes (1 ha, 10 ha, and 100 ha) versus continuous forest. We collected data in 6 research cycles from July–August 2003 and January 2005–June 2006 at the Biological Dynamics of Forest Fragments Project (BDFFP), north of Manaus, Brazil. For each cycle, we followed the monkeys at each study site from dawn until dusk for 3 consecutive days, and recorded their location. Although bearded saki monkeys living in 10-ha and 1-ha fragments had smaller day ranges and traveled shorter daily distances, they traveled greater distances than expected based on the size of the forest fragment. Monkeys in the small fragments revisited a greater percentage of feeding trees each day, traveled in more circular patterns, and used the fragments in a more uniform pattern than monkeys in the continuous forest. Our results suggest that monkeys in the small fragments maximize their use of the forest, and that the preservation of large tracts of forest is essential for species conservation. Species with large home ranges sometimes inhabit forest fragments, but doing so can alter behavior, demographics, and ecology, and the monkeys may be vulnerable to stochastic events.  相似文献   

16.
颜尉珂  雷宇  王磊  张新宇  刘强 《生态学报》2023,43(24):10387-10398
气候变化和人为引种正在改变世界物种的分布格局,对生态系统中的关键物种构建分布模型,有助于理解全球气候变化背景下物种的分布变化规律,并预测其对生态系统的潜在影响。灰喜鹊(Cyanopica cyanus)是重要的食虫鸟类,对控制虫害、维持森林生态系统的稳定性具有重要意义,由于人为引种等原因,目前灰喜鹊已在其自然分布地外建立了多处可自我维持的种群。基于气候生态位理论,使用最大熵模型构建了自然分布地模型、引入地模型及综合分布模型等3种模型,模拟灰喜鹊在当前时期、2050s时期及2070s时期的潜在适生区,并以此分析灰喜鹊的分布格局与变化趋势。结果表明:(1)当前时期,自然分布地种群的适生区主要分布于华北、华中和华东地区,而引入地种群的适生区则主要分布于华南和西南地区;(2)在未来气候变化的背景下,各模型结果均表明灰喜鹊有显著的扩张趋势,自然分布地种群主要表现为向高纬度、高海拔地区扩散,截至2070s时期,适生区的质心向北偏东25°方向移动了229.16 km,而引入地种群扩张趋势较缓,截至2070s时期,质心仅向北偏东46°方向移动了67.69 km;(3)从适宜值方面来看,自然分布地模型中...  相似文献   

17.
侯沁文  铁军  白海艳 《生态学报》2014,34(23):6954-6962
选择山西蟒河猕猴国家级自然保护区针阔叶混交林、阔叶落叶林、杂木林和灌木林4种植被类型为调查样地来初步了解蛾类群落结构及多样性。共采集蛾类标本4709只,隶属24科184种,其中螟蛾科种类和个体数量最多。在4种植被类型中,灌木林的蛾类种数最多,有20科132种,灌木林中螟蛾科为优势科;阔叶落叶林中最少,14科74种,尺蛾科为优势科;针阔叶混交林和杂木林居中,其中前者优势科不明显,后者以草螟科占优势。对4种植被类型中蛾类物种丰富度、多度、多样性和均匀度指数进行了计算和分析,结果表明:蛾类的多度指数在阔叶落叶林中显著低于其余3种植被类型;蛾类的丰富度、多样性和均匀度指数在灌木林中均最高,在针阔叶混交林和杂木林中则相近。蛾类种-多度曲线在针阔叶混交林、杂木林和灌木林中符合对数正态分布模型,而在阔叶落叶林中不符合对数正态分布模型。  相似文献   

18.
Three of 16 juvenile rhesus monkeys (Macaca mulatta) and 1 rhesus of 79 adult rhesus and cynomolgus monkeys (Macaca fascicularis) were found comatose in a state of profound hypothermia after a heating failure occurred in the room in which they were housed. One juvenile monkey died shortly thereafter. The three other monkeys were revived with gradual warming and supportive therapy but later experienced separate acute clinical crises manifesting shock and died at 19, 31, and 51 days after the initial episode. Histopathologic findings of severe bone marrow depletion were observed in each of the three monkeys that died after the initial episode.  相似文献   

19.
The main objective of this study was to estimate the population density and demographic structure of spider monkeys living in wet forest in the vicinity of Sirena Biological Station, Corcovado National Park, Costa Rica. Results of a 14-month line-transect survey showed that spider monkeys of Sirena have one of the highest population densities ever recorded for this genus. Density estimates varied, however, depending on the method chosen to estimate transect width. Data from behavioral monitoring were available to compare density estimates derived from the survey, providing a check of the survey’s accuracy. A combination of factors has most probably contributed to the high density of Ateles, including habitat protection within a national park and high diversity of trees of the fig family, Moraceae. Although natural densities of spider monkeys at Sirena are substantially higher than those recorded at most other sites and in previous studies at this site, mean subgroup size and age ratios were similar to those determined in previous studies. Sex ratios were similar to those of other sites with high productivity. Although high densities of preferred fruit trees in the wet, productive forests of Sirena may support a dense population of spider monkeys, other demographic traits recorded at Sirena fall well within the range of values recorded elsewhere for the species.  相似文献   

20.
The North American greater snow goose population has increased dramatically during the last 40 years. We evaluated whether refuge creation, changes in land use on the wintering and staging grounds, and climate warming have contributed to this expansion by affecting the distribution, habitat use, body condition, and migration phenology of birds. We also reviewed the effects of the increasing population on marshes on the wintering grounds, along the migratory routes and on the tundra in summer. Refuges established before 1970 may have contributed to the initial demographic increase. The most important change, however, was the switch from a diet entirely based on marsh plants in spring and winter (rhizomes of Scirpus/Spartina) to one dominated by crops (corn/young grass shoots) during the 1970s and 1980s. Geese now winter further north along the US Atlantic coast, leading to reduced hunting mortality. Their migratory routes now include portions of southwestern Québec where corn production has increased exponentially. Since the mid‐1960s, average temperatures have increased by 1–2.4°C throughout the geographic range of geese, which may have contributed to the northward shift in wintering range and an earlier migration in spring. Access to spilled corn in spring improved fat reserves upon departure for the Arctic and may have contributed to a high fecundity. The population increase has led to intense grazing of natural wetlands used by geese although these habitats are still largely undamaged. The foraging in fields allowed the population to exceed limits imposed by natural marshes in winter and spring, but also prevented permanent damage because of their overgrazing.  相似文献   

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