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An investigation of the distribution and population of chimpanzees in the Republic of Guinea was carried out with the help
of the Government authorities on the basis of a questionnaire. As a result, at least 20 out of the 36 prefectures in the country
were confirmed to be inhabited by chimpanzees, and the estimated total number of animals in the present population amounted
to 6,625. This number represented an approximately 50% reduction from the 13,940 estimated by the same informants on the same
questionnaire based on assumptions for the past (20–60 years ago). On comparing these data with our observations in some localities,
the present number of chimpanzees as estimated from the questionnaire appeared to be overestimated. Among the 16 other prefectures
without any reply, at least 7 have chimpanzees according to our own and our colleagues' observations. On our modest estimate,
the number of chimpanzees at present could be only about 1,420 for 30 prefectures rather than 6,625 for 20 prefectures. The
true population size in the whole country may lie between the two estimates, 1,420–6,625, even including other prefectures
with no information. The reduction in population size during the last 20–60 years must be half or even more. The reason for
this drastic reduction of the chimpanzee population is thought to be mainly the destruction of its habitat and poaching in
some prefectures adjacent to Sierra Leone and Liberia. These findings emphasize that urgent efforts need to be directed towards
the conservation of the chimpanzees and their habitat, especially through international cooperative programmes. 相似文献
3.
Preliminary studies for the population estimation of the cryptomeria red mite,Oligonychus hondoensis
This is the second paper dealing with techniques necessary to the population estimation of the Cryptomeria red mite feeding on a coniferous Cryptomeria tree, with the final object of determining the absolute population. Results are as follows:
- The population can be defined as the whole of mites existing on branches with foliage younger than two years old, because more than 95% of individuals are always there.
- Optimal sampling unit varies according to mite population. Unless a fixed unit is necessary, seasonal placement of units is recommended.
- Since significant variance is associated with crown levels, representative sampling from each level is designed. These calculation should be based on the data transformed to logarithms, as the relation between mean and variance suggests that the population data are of contagious distribution.
- A trial to calculate the total length of branches for each age, which is needed for the conversion to absolute population, is described.
4.
Report on the distribution,population, and ecology of the yunnan snub-nosed monkey (Rhinopithecus bieti) 总被引:2,自引:0,他引:2
Yongcheng Long Craig R. Kirkpatrick Zhongtai Xiaolin 《Primates; journal of primatology》1994,35(2):241-250
The Yunnan snub-nosed monkey (Rhinopithecus bieti), an endangered species in China, has received more protection in theory than in practice. Therefore it is on the very verge
of extinction. The population of the species was estimated less than 2,000 individuals spread in 19 distinct groups. It was
confirmed that the monkey was confined to the Yunling Mountain System, the area between the Yangtze River (Changjiang, aka
Jinshajiang) to the east and the Mekong River (Lancangjiang) to the west. We further concluded that a lowland belt to the
east, about 100 km long and 20 – 30 km wide was not suitable habitat for the monkeys, and appeared to serve as the natural
ecogeologic barrier for the species. Our results indicated that the southern limit of the distribution was at Longma (26°14′N),
and that the northern limit of the distribution was at Xiaochangdu (29°20′N). The distribution area of the species was substantially
smaller than previously estimated. There were substantial ecological differences between the southern and northern parts of
the species range. The monkey was found only in fir-larch forest. 相似文献
5.
Seiji Hayashi Kenji Hayasaka Osamu Takenaka Satoshi Horai 《Journal of molecular evolution》1995,41(3):359-365
We analyzed the 896 base-pair (bp) mitochondrial DNA (mtDNA) sequences for seven gibbons, representative of three out of four subgenera. The result from our molecular analysis is consistent with previous studies as to the monophyly of subgenus Hylobates species, yet the relationship among subgenera remains slightly ambiguous. A striking result of the analysis is the phylogenetic location of Kloss's gibbon (H. klossii). Kloss's gibbon has been considered to be an initial off-shoot of the subgenus Hylobates because of its morphological primitiveness. However, our molecular data strongly suggest that Kloss's gibbon speciated most recently within the subgenus Hylobates.
Correspondence to: S. Horai 相似文献
6.
Flexibility, or a capacity for situational variation, is an important characteristic of gibbon vocalization—one which may
be seen as necessary to the functional effectiveness of species-typical songs. This paper reviews literature reporting flexibility
of gibbon vocal behavior in relation to reinforcement contingencies, the singing of neighboring gibbons, development of pair
coordination in the duet-singing of siamang gibbons, sequential progression in the elaboration of organizing sequences in
siamang gibbons, and “repairs” of organizing and great-call sequences. A theoretical framework to account for the development
of flexibility in species-typical behaviors is drawn on the basis ofGlickman's andSchiff's (1967) proposal of the reinforcing power of species-typical behaviors and associated feedback and consequent stimuli. 相似文献
7.
渤海是黄渤海江豚种群的重要分布区,但是有关该区域江豚的种群数量的资料极其匮乏。2015年至2016年,采用截线抽样法在渤海水域开展了6个航次的目视调查,收集了渤海江豚的分布数据,首次评估了区域内的江豚种群数量,为制定有效的渤海江豚种群生态保护策略提供了基础资料。调查结果显示,在2015年8月、2016年5~7月、9月和11月进行的6个调查航次共计8972 km的有效航程中,发现江豚87次、136头次。江豚在渤海各海湾和中部水域都可观察到;14:00-18:00时段、离岸15~35km范围内较易观察到江豚;黄河口外、秦皇岛东北侧老龙口和莱州外沿岸河口水域,江豚出现频次较多。各季节中,以5月在黄河口外20~40km范围内发现江豚的频次和数量最多。采用Distance 7.0软件估算渤海江豚种群数量,其中探测概率分别取值0.399、0.85和1时,渤海江豚种群数量估算值分别为7883头(CV=0.21)、3701头(CV=0.21)和3124头(CV=0.21),对应的种群密度分别为1.441头/km2、0.066头/km2和0.056头/km2,均低于已报道的南黄海和日本海江豚种群相应值。受海上天气、调查条件和经验所限,本文估值可能存在偏差,但限于渤海江豚历史资料缺乏的现状,本文的结果对于认识渤海江豚的种群状况仍具有重要参考意义。 相似文献
8.
Susan M. Cheyne David J. Chivers Jito Sugardjito 《Biodiversity and Conservation》2008,17(7):1741-1751
We observed and recorded the behaviours of gibbons undergoing rehabilitation, before and after release, to document the behavioural
and social changes of gibbons in the rehabilitation program and develop criteria for determining the suitability of a pair
of gibbons for release. Hylobates albibarbis were observed at the Kalaweit Gibbon Rehabilitation Project in Kalimantan, Indonesia. Data were collected on animals both
pre- and post-release and on wild gibbons for comparison. Data presented here show that reintroduced gibbons are capable of
surviving without human intervention. In addition, their behaviour is similar to that of wild gibbons in terms of activity
budgets, position in the canopy, body posture, pair association (PA) and diet. Prior to this study, no attempt has been made
to quantify the rehabilitation process for gibbons, and rehabilitation project personnel require data reporting all aspects
of a release so that improvements can be made. It is important to report these data for the benefit of future releases. Criteria,
based on the behaviour of wild gibbons, are proposed to assist rehabilitation centers in assessing the suitability of gibbon
pairs for release. 相似文献
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10.
A new estimator for the finite population distribution function 总被引:2,自引:0,他引:2
11.
普氏原羚的分布和种群数量调查 总被引:8,自引:1,他引:8
2003 年8 ~9 月,对青海省境内普氏原羚的分布和种群数量进行了专项调查。调查结果表明,普氏原羚现存7 个种群,累计数量为602 只;其中塔勒旋果种群属首次报道。与以往报道相比,目前元者和鸟岛种群数量呈下降趋势;海晏—刚察种群数量增长明显;湖东—克图种群数量有所回升,但仍没有达到20 世纪80 年代中期时的种群数量。普氏原羚种群数量变化与栖息地质量及人为干扰程度有密切相关。本次调查显示,普氏原羚现存栖息地呈不连续的间断分布,随着区域经济开发力度的加大,其栖息地在不断缩减、生存环境质量仍在继续恶化。 相似文献
12.
Tatsuro Kono 《Population Ecology》1953,2(1):95-105
Contributions from the Entomological Laboratory, Kyoto University, No. 231. 相似文献
13.
中国长臂猿科动物的分类和保护现状 总被引:3,自引:0,他引:3
根据最新的长臂猿科分类系统和近年来开展的多次长臂猿调查,本文对我国长臂猿科的分类和保护进行了全面的回顾和综述,将为以后中国长臂猿的研究和保护提供基础资料。长臂猿科(Hylobatidae) 分为4 个属(Nomascus,Symphalangus,Hylobates, Hoolock ) 17 个种,其中我国分布有3 属6 种: 西黑冠长臂猿(N. concolor)、东黑冠长臂猿(N. nasutus)、海南长臂猿(N.hainanus)、北白颊长臂猿(N. leucogenys)、东白眉长臂猿(Hoolock leuconedys)和白掌长臂猿(Hylobates lar)。长臂猿曾经广泛分布于我国大部分地区,受栖息地丧失、退化和猎杀等因素的影响,目前长臂猿仅分布于云南、广西和海南等地。我国长臂猿的保护形势十分严峻,白掌长臂猿和北白颊长臂猿可能已经从中国消失;东黑冠长臂猿和海南长臂猿的数量都不足30 只,接近灭绝边缘;东白眉长臂猿的数量不足200 只;即使是数量最多的西黑冠长臂猿,其数量也仅有1 000 至1 300 只。严格执法、意识教育、科普宣传、长期的科学研究将有利于我国的长臂猿保护。 相似文献
14.
Thomas Geissmann 《Primates; journal of primatology》1991,32(3):357-363
White-handed gibbons (Hylobates lar) are not known to occur to the east or southeast of Bangkok. The reliably documented localities ofH. lar nearest to this area are about 120 km northeast of Bangkok. There, in the Kao Yai National Park, is the only known zone of
contact betweenH. lar and the pileated gibbon (H. pileatus), another species of the so-calledlar group. Unpublished documents dating from 1925 indicate, however, that sympatry between these two species may also have existed
in the region of Sriracha, about 80 km southeast of Bangkok. Therefore, a large zone of overlap in the distribution of the
two species may originally have existed. In most parts of this hypothetical zone, gibbon habitat appears to have been destroyed,
with the Khao Yai Park possibly representing the last remnant of the once large contact zone. 相似文献
15.
Cheyne SM Thompson CJ Phillips AC Hill RM Limin SH 《Primates; journal of primatology》2008,49(1):50-56
We demonstrate that although auditory sampling is a useful tool, this method alone will not provide a truly accurate indication
of population size, density and distribution of gibbons in an area. If auditory sampling alone is employed, we show that data
collection must take place over a sufficient period to account for variation in calling patterns across seasons. The population
of Hylobates albibarbis in the Sabangau catchment, Central Kalimantan, Indonesia, was surveyed from July to December 2005 using methods established
previously. In addition, auditory sampling was complemented by detailed behavioural data on six habituated groups within the
study area. Here we compare results from this study to those of a 1-month study conducted in 2004. The total population of
the Sabangau catchment is estimated to be about in the tens of thousands, though numbers, distribution and density for the
different forest subtypes vary considerably. We propose that future density surveys of gibbons must include data from all
forest subtypes where gibbons are found and that extrapolating from one forest subtype is likely to yield inaccurate density
and population estimates. We also propose that auditory census be carried out by using at least three listening posts (LP)
in order to increase the area sampled and the chances of hearing groups. Our results suggest that the Sabangau catchment contains
one of the largest remaining contiguous populations of Bornean agile gibbon. 相似文献
16.
Cathaya argyrophylla Chun et Kuang is a China endemic and endangered evergreen conifer, listed in the Red Data Book of plant in China, with less than 5000 individuals remaining on earth. The age structure of C. argyrophylla population in Bamianshan Mountain showed its stability, but was different among metapopulations, especially in the aged Cathaya forests there often appeared a lack of generation continuety. Though the aboveground biomass of the population varied from 30000 kg · ha-1 to 110000 kg · ha-1 with different metapopulations, the increment of the biomass had no significant difference among metapopulations but could basically reflect the productivity of this population in that area. Its distribution patterns were mainly contagious, even when the shrub cover was very high and random in young Cathaya stands. 相似文献
17.
18.
One hundred and forty mammals of fifteen different species belonging to nine families, collected during one-year survey period in Turaif province of Saudi Arabia, are reported. Collections were made during studying the diversity of land vertebrate fauna of Turaif area at the northern province of Saudi Arabia. Cricetidae (n?=?64) was the most common family. Jaculus jaculus vocator (n?=?34) was recorded the highest number of events for any mammal in the surveyed area followed by Gerbillus nanus (n?=?23). Two species of mammals namely G. nanus (n?=?23) and Felis margarita (n?=?3) were reported for the first time in the study area. The geographical distribution of the collected species within this province was mapped. 相似文献
19.
沙地云杉种群结构与动态的研究 总被引:20,自引:5,他引:20
本文用种群大小结构代替年龄结构研究了沙地云杉种群的大小结构、分布格局和动态规律。结果表明,样地1、2、3、5的沙地云杉种群属于增长型,样地4的沙地云杉种群为稳定型,将样地1、2、3作为一块样地,其分布格局为集群型,但从幼树到大树,则由集群分布变为随机分布。 相似文献
20.
坡向对四川冶勒红豆杉种群分布格局的影响——基于斑块信息的分析 总被引:8,自引:1,他引:8
在斑块信息的基础上,利用GIS技术分析了坡向对四川冶勒红豆杉种群分布格局的影响.结果表明,冶勒红豆杉种群主要分布在西北向、东北向、东向和北向斑块上,这些斑块在分布面积、平均斑块大小、平均斑块周长以及红豆杉个体的分布数量方面均占绝对优势.红豆杉种群的分布同坡向之间存在极显著的关联性,种群优先分布于北坡、东北坡、西北坡和东坡斑块,其次为西坡和西南坡斑块,最后为平地和东南坡斑块.冶勒红豆杉种群的分布格局绝大多数为聚集分布(除南向斑块外).其中,种群聚集强度最大的是北向斑块,其CE值高达0.906,其次为东北向、西北向斑块,其CE值分别为0.797和0.563,而其余坡向斑块上的CE值均低于0.5.聚集强度CE值与斑块数量、斑块总周长以及斑块上分布的红豆杉个体数呈显著正相关(相关系数分别为0.936、0.735和0.802),而与斑块面积、平均斑块大小、平均斑块周长、平均形状指数无显著相关. 相似文献