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1.
九寨沟自然保护区川金丝猴的分布及种群数量   总被引:1,自引:0,他引:1  
2014年2月至5月,对四川省九寨沟自然保护区野生川金丝猴的种群分布、数量及其社会结构进行调查,初步探讨该种群与其他种群在外部形态和社会结构方面的差异性。采用"V"型路线法调查,发现九寨沟保护区共有川金丝猴4群。然后结合长时间的持续跟踪观察,证实家庭单元19个,全雄群3个,能区分不同个体296只。OMU大小平均为12.7只,其中OMU内的成年个体占38%,青少年个体占53%,幼仔占9%。成年与青少年比例为1∶1.39,成年雌雄的比例为3.84∶1。与秦岭种群的外部形态相比,该种群的成年雄性更为壮大,毛发弯曲程度明显;成年雌性毛发略显灰黑色,金黄色暗淡,大部分个体嘴角长有很小的肉瘤;青少年个体毛色泛白。亦发现九寨沟种群倾向于选择海拔偏高(2400—3550 m)的针叶林带活动。  相似文献   

2.
海南南湾猕猴种群增长的研究   总被引:3,自引:0,他引:3  
江海声  练健生 《兽类学报》1998,18(2):100-106
对海南南湾猕猴1965~1994年间的种群动态和雌性猴生命表的研究表明,该种群年均增长率为9.7%,1987年后种群增长率和繁殖率有所下降,猴群中非成年猴比例已不足50%。半驯化雌性猴的逐年存活率到17岁仍达0.58,通过对存活曲线和寿命期望曲线的分析,南湾雌猴寿命可达33~38岁。婴猴死亡率较低、成年猴死亡率较高,存活曲线属Ⅰ形即凸形。研究表明静态生命表编制方法不适于灵长类,在建立标准化存活曲线时应考虑种群综合死亡系数。猕猴通过存活率、繁殖率、群体结构变化等社群调节机制达到种群平衡。对南湾猕猴近年内每年可捕捉利用100~150只左右,10岁以上的猴应占50%以上,在不影响种群遗传多样性水平上,可适当多捕一些成年雄猴。  相似文献   

3.
山地麻蜥生态的初步研究   总被引:1,自引:0,他引:1  
山地麻蜥主要栖息在市郊海拔大于100m的山丘上部及山顶。研究结果表明,山地麻蜥正常密度大约为1只/100m^2,其数量与山丘土石状况、植被盖度及海拔高度有一定关系,与植被类型关系不大。山地麻蜥似乎有一定的“护洞”行为。主食昆虫和蜘蛛,春季食物生态位宽度大于秋季,食物生态位重叠度为0.61。性比变化较大,出蛰仞期和冬眠前期雄多雌少;而5~10月份期间,性比接近1。幼体至成体发育期间,雄性生长快于雌性;但成年期后,雌性头体部分的生长快于雄性,可能与怀卵有关。山地麻蜥种群可分为4个年龄组,个体数量比约为幼年:亚成年:成年A:成年B≈1.8:1.9:3.1:1,但成体与非成体的数量比约为1.2:1,应属于稳定型种群。个体自然寿命约为5.5~6周年。人类干扰是山地麻蜥种群下降的原因之一。  相似文献   

4.
为了评价生态保留带对小型兽类种群的影响,2003年7月至2004年6月在瑞士西部Salavaux,chevmux和Montbrelloz 3个地区采用标志重捕方法对小型兽类种群进行了研究。在3个生态保留带中,共发现6种1206只小型兽类,其中普通田鼠、小林姬鼠、中麝晌捕获数量多。普通田鼠为优势种。普通田鼠的种群数量在生态保留带间有差异,但具有相同的季节性波动趋势,一般种群数量随着植被覆盖度和食物丰富度的增加,春季末开始出现增加,仲夏达到最高水平。种群中雌雄个体年龄结构之间有明显的差异,成体和亚成体的数量比幼体多,雄性亚成体的数量比雌性多,雌性成体数量比雄性多(X^2=44.09,df=10,P〈0.001,N=203)。普通田鼠种群中雌雄个体体重之间有明显的差异,雄性的体重比雌性大(t一检验:t=5.011,df=162,P〈0.05,N=213)。种群性比之间有明显的月间变化,雌性的捕获次数比雄性大。普通田鼠只在短距离范围内活动,在生态保留带中的巢区为350~400m^2,雌雄个体的巢区大小之间没有显著性差异。  相似文献   

5.
麻应太  田联会 《兽类学报》2002,22(4):248-253
1998年1-白对牛背梁国家级自然保护区内羚牛种群数量与分布做了调查。结果表明,保护区内有11群羚牛,总数量119-130头(包括独牛),整个保护区内羚牛分布密度为0.0073-0.0079头/hm^2。在冬季,羚牛分布于海拔1900-2700m块相互隔离的栖息地中,以海拔2200-2600m之间分布更为集中。在1981-1998年的17年间,保护区内的羚牛种群分布范围在逐渐缩小;从上世纪50年代至90年代,羚牛最低的分布高度比历史分布高度至少上升了400m,周边地区人为干扰,生境不断丧失和保护区内生境破裂化是导致羚牛分布现状最直接的原因。  相似文献   

6.
贺兰山岩羊种群结构的季节性变化   总被引:12,自引:2,他引:10  
2001年3月至2002年2月,每月定期在固定的样线上,采用样线法对贺兰山3929只岩羊种群结构进行调查。小群体是贺兰山岩羊种群的基本特征,全年群平均数为5.5只,独羊全年存在,以雄性成体为主,在雌性群中,母仔群全年稳定,占雌性群的44.0%。岩羊雌性群群体大小平均3.5只,雄性群群体平均4.5只,混合群群体平均8.0只;全年雌性多于雄性,雌性群小于雄性群。群体表现为雌性群群体小,群体数量多;混合群体大,群体数量少。混合群群体大小范围离散,雄性群次之,雌性群群体范围变化最小。全年雌幼比为100:48。雌雄性比全年100:71,其中,2~6月份,雌雄性比为100:130~155;7—12月份,雌雄性比为100:43.68。另外,中还指出3.5~8.5龄雄羊占63.9%,1.5~3.5龄和超过8.5龄老年雄性岩羊所占的百分率明显较少。  相似文献   

7.
黄龙大熊猫种群数量及年龄结构调查   总被引:6,自引:0,他引:6  
1996年6 ̄10月,在野外采用路线-聚类法对黄龙寺自然保护区内大熊猫种群数量进行了调查。结果表明:保护区内现有大熊猫23只,竹林内生态密度为0.439只/km^2。此外,首次采用了离差平方和聚类的方法,将该种群划分为4个年龄组。其中幼年组个体上占13.33%,青年组个体占6.67%,成年组个体占60%,老年组个体占20%。最后还对结果进行了讨论。并提出了保护措施。  相似文献   

8.
海南坡鹿种群生活史特征及种群动态趋势预测   总被引:1,自引:1,他引:0  
本文应用生命表和Leslie矩阵等生活史常规研究方法,分析了生存于海南邦溪自然保护区的国家I级珍稀濒危哺乳动物海南坡鹿种群的年龄结构、特定年龄存活率、特定年龄繁殖率、初次产仔年龄、产仔季节、性比、寿命等重要生活史特征,并预测其种群动态趋势.邦溪海南坡鹿种群平均寿命4.6岁,雌性平均寿命略高于雄性,分别为4.7岁,4.4岁;雌性平均初次产仔年龄为24月龄;雌性平均性成熟年龄为16月龄;雌性最长繁殖寿命为8.5岁,雄性最长繁殖寿命约为4岁;成年雌性平均一年一胎,胎仔数为1;新生幼仔数量雄性大于雌性,性比为1.33∶1;种群动态生命表的分析结果表明,各年龄段雄性存活率高于雌性.幼体(0~2岁)死亡数雌性高于雄性,壮年成体(3~8岁)死亡数雄性高于雌性,老体(9岁~)死亡数两性几乎相等.雌性幼体受到较强的自然选择作用,体弱个体被淘汰;壮年雄体为繁殖付出较高的代价,死亡个体数量较高.Leslie矩阵预测结果表明,如果影响出生率和死亡率的因子不变,种群数量将逐年增长,周限增长率为λ≈1.011; 种群内禀增长率r≈0.012;种群世代增长率R0 ≈1.06;世代长度T≈5.12年.产仔时间为秋季与冬季,春、夏季节不产仔,此为适应海南岛独特的热带环境选择压力的结果.  相似文献   

9.
秦岭羚牛中独栖现象的初步观察   总被引:12,自引:4,他引:8  
曾治高  宋延龄 《兽类学报》1999,19(3):169-175
在群栖的秦岭羚牛种群中,存在着少数单独活动的羚牛,称为独牛。野外见到独牛50只次,占见到羚牛总数的459%。独牛中有老年雄性个体、青壮年雄性个体、雌性个体、亚成体和幼仔。在繁殖季节独牛出现的次数最多,其中大部分是雄性个体,也有雌性个体。与羚牛的四川亚种不同,在秦岭亚种中很少见到公牛集群的现象。羚牛种群中独牛的形成主要与繁殖有关,同时还与疾病及防御迁移有关。独牛在不同季节、不同生境内均可见到,绝大多数老年独牛活动区域的海拔高度低于集群的羚牛活动的高度。老年独牛在离群活动后,其活动节律与群体中的雄牛有一定的差异,这种差异在夜间的活动时间和活动率方面表现得更加明显。  相似文献   

10.
在2006年6月至2007年9月,通过种群个体识别、社区监测网络、样线调查和村寨访问等方法对尚勇保护区亚洲象的种群动态和季节性分布格局进行研究.结果显示:目前在尚勇保护区的亚洲象种群数量约为68头;拍摄到亚洲象共计347头次,通过个体识别方法识别出亚洲象53头,其中幼体、青少年体、亚成体和成体数量及所占比例分别为:3(...  相似文献   

11.
Two alternative models are used to explain maintenance of polymorphism of B chromosomes (Bs) in populations of a great number of species. The parasitic model suggests deleterious effects of Bs on fitness of carriers, while the heterotic model assumes that, in the absence of drive, equilibrium is produced by beneficial effects of Bs at low numbers. In order to determine the potential contribution of Bs to genetic differentiation and diversity, four populations of Apodemus flavicollis, differing in frequency of Bs (from 0.23 to 0.38) and settled in ecologically different habitats, were analyzed by 471 AFLP markers. Although numerous loci were demonstrated to be population specific, none of them was associated with individuals with Bs. AMOVA showed that the presence of Bs does not affect population differentiation, pointing to greater genetic similarity of Bs to A chromosomes. The greatest genetic diversity (0.241) was found in the population settled in optimal conditions for this species featured by the lowest frequency of animals with Bs (0.23). We found that the majority of loci marked as loci under directional selection, are characteristic of either a population with lower or one with a higher frequency of Bs. Several loci detected as outliers were associated with environmental variables that could directly and/or indirectly influence population dynamics of A. flavicollis. Thus, we suggest that the different frequency of Bs carriers in populations is related to adaptive differentiation to diverse habitats, which is in accordance with the heterotic model of Bs maintenance.  相似文献   

12.
13.
Eighty-five sifakas (Propithecus verreauxi) have been captured, marked, released, and monitored between September 1984 and August 1988 at the Beza Mahafaly Special Reserve in southwest Madagascar. Estimates are presented of the age and sex structure of this population and of age-specific fertility and survival. Using data from this and other studies, it is shown that sifaka tertiary sex ratios do not depart significantly from 50:50, but that they do differ significantly from those of haplorhine primates, which have strongly female-biased tertiary sex ratios. Two demographic mechanisms that could give rise to this distinction are considered: 1) intermittently male-biased birth cohorts among sifakas and 2) different patterns of survivorship in haplorhines and sifakas.  相似文献   

14.
In this study, mitochondrial 16S rRNA and cytochrome b sequences were used to infer the genetic structure of Pseudopus apodus (Pallas, 1775) populations sampled from 40° North latitude of Turkey. Mean percent G-C contents of 47.13 and 46.66 were determined for 16S rRNA and cytochrome b datasets, respectively. Two haplotypes were found using 16S rRNA dataset, with 6 variable loci and a haplotype diversity of 0.1053, while Cytochrome b dataset consist of 10 haplotypes, with 18 variable loci and a haplotype diversity of 0.1943. Also mean genetic distance was found to be eight times higher in the cytochrome b dataset. Kimura 2-parameter genetic distance matrix was evaluated together with neighbor joining tree and median joining network in order to reveal possible divergence points in both datasets. Results indicated signs of 3 regional populations, including potential cryptic species from Digor or subspecies from Samsun and Sinop.  相似文献   

15.
Distribution of Gm and Km allotypes among ten populations of Assam, India   总被引:1,自引:0,他引:1  
Serum samples from ten endogamous populations of Assam, India-Brahmins, Kalitas, Kaibartas, Muslims, Ahoms, Karbis, Kacharis, Sonowals, Chutiyas, and Rajbanshis-were typed for G1m (1, 2, 3, 17), G3m (5, 10, 11, 13, 14, 15, 16, 21, 26), and Km (1). Among Brahmins, Kalitas, Kaibartas, Muslims, Ahoms, Sonowals, Chutiyas, and Rajbanshis, five different Gm haplotypes were found: Gm1,17;21,26; Gm1,17;10,11,13,15,16; Gm1,2,17;21,26; Gm1,3;5,10,11,13,14,26; and Gm3;5,10,11,13,14,26. Kacharis and Karbis show only four of these haplotypes: Gm3;5,10,11,13,14,26 is absent among them. The intergroup variability in the distribution of these haplotypes is considerable, which can be explained by the ethnohistory of these populations. Genetic distance analysis, in which five Chinese population samples were included, revealed the existence of three main clusters: 1) North and Central Chinese; 2) Kalitas, Kaibartas, Chutiyas, Rajbanshis, Muslims, and Brahmins; and 3) Ahoms, Sonowals, Kacharis, South Chinese, and Karbis. The clusters suggest some genetic relation between these four Assamese populations and South Chinese, which is again understandable considering the ethnohistory of the populations of Northeast India. In the Km system, too, a remarkable variability is seen in distribution of phenotype and allele frequency.  相似文献   

16.
Experimental research has identified many putative agents of amphibian decline, yet the population-level consequences of these agents remain unknown, owing to lack of information on compensatory density dependence in natural populations. Here, we investigate the relative importance of intrinsic (density-dependent) and extrinsic (climatic) factors impacting the dynamics of a tree frog (Hyla arborea) population over 22 years. A combination of log-linear density dependence and rainfall (with a 2-year time lag corresponding to development time) explain 75% of the variance in the rate of increase. Such fluctuations around a variable return point might be responsible for the seemingly erratic demography and disequilibrium dynamics of many amphibian populations.  相似文献   

17.
C. A. Toft 《Oecologia》1987,73(3):338-350
Summary This paper documents population structure in a solitary wasp, Microbembex cubana (Hymenoptera, Sphecidae, Nyssoninae), on a small (15 km2) Bahamian island. A relatively isolated portion of this population was studied April–June 1985. The population comprised small aggregations of territorial males and nesting females. Individuals of both sexes were with rare exceptions faithful to a home aggregation during their one- to two-month adult lifespans, conducting all reproductive activities there. Individuals from different aggregations, however, mixed daily during these activities: feeding on nectar, hunting for provisions and retiring to clustered sleeping burrows. Significant variation occurred among the nine breeding aggregations in size, density, sex-ratio (which was on average 2:1 in favor of males) and survival (which was 0.93–0.99 per individual/per day and which was not higher for females than for males). Aggregations retained the same characteristics for longer than the life expectancies of individuals in them.Factors affecting reproductive success and survivorship in M. cubana are complex: they are apparently only partially overlapping between males and females and subject to spatial variation. Patterns in the data suggest several hypotheses about how behavior, morphology and habitat interact to shape population processes. I propose that aggregations arise and are characterized by considerable behavioral inertia because individual M. cubana use conspecifics as sources of information on resource quality. Because M. cubana occurs in secondary habitats, individuals retain flexibility in responding to better opportunities for reproduction, but this population exhibits more viscosity than reported for other ground-nesting solitary Hymenoptera.  相似文献   

18.
Existence, uniqueness and asymptotic stability of stochastic equilibrium are established in multi-dimensional population models with monotone dynamics.  相似文献   

19.
Blood samples from 103 Kotas and 58 Badagas residing in the Nilgiri Hills, South India, were examined for HLA-A and -B antigen profiles. The Kota group was characterized by fairly high frequencies of A2 and B7 antigens as well as the haplotype A2-B7. The frequencies of Aw19, A28, and Bw22 were found to be higher in Badagas than in Kotas. The results are compared with the literature available on other Indian populations.  相似文献   

20.
澄清植物种类是植物分类学研究的基础,也是开展iFlora编研的前提,而植物物种调查则为其提供了最为基础和重要的研究素材。传统的植物物种调查,或以植物区系调查为目的,或是专类植物资源搜集.往往较为忽视种群层面的调查。iFlora计划中,基于地方种群的植物物种调查应予以重视和贯彻实施。系统的植物物种调查将以“个体(标本)一(地方繁育)种群一物种”为核心展开,其中地方繁育种群是调查的中心环节。调查内容将兼顾种群的形态学、生态学和遗传学三方面的学科需求,以期获得全面详实的物种数据,并藉此建立一套完整规范的物种“档案”。在整个植物物种调查中,“模式产地种群”是关注的重点,需制定缜密的调查方案并优先实施。由于模式标本的残缺、原始描述的简略,在未来的物种分类研究中,植物分类学者必须认真考虑“产地模式标本”和“模式产地种群”所扮演的重要角色。作为自然界中客观存在的群体,“模式产地种群”不仅仅是模式标本的注脚和补充,它犹如地质学上的“金钉子”.将为研究者提供最为权威和充分的形态学、生态学和遗传学等研究信息,从而真正将物种分类研究从“故纸堆”的困境中解放出来。  相似文献   

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