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1.
The Cao Vit gibbon is a critically endangered species with only about 110 individuals remaining in a degraded karst forest along the China-Vietnam border. Behavioral data from this site are particularly useful in understanding gibbon behavioral adaptations to different sets of ecological conditions and will contribute to the conservation of the species. We studied seasonal variation in the time budget and diet of the Cao Vit gibbon in response to variation in food availability and ambient temperature by observing two groups for 1,379 hr between January and December 2009. We used 5-min scan samples to record the activity of gibbons. Both ambient temperature and food availability varied from month to month. Gibbon groups increased resting time and huddled together in sleeping places in cold months. Gibbons spent more time feeding on fruit when fruit was more abundant suggesting that fruit was their preferred food. Alternatively, leaf eating was negatively correlated with leaf availability which suggested that leaves may be used as a fallback food. Gibbons increased their diet diversity when they ate more leaves. This might be a strategy to cope with toxins or digestion inhibitor accumulation associated with feeding from a limited number of leaf species. Individuals consumed more buds when Broussonetia papyrifera produced buds in March and April. During this period, they decreased traveling time and engaged in less frequent social interactions. Gibbons spent more time searching for and feeding on invertebrates during June and October. However, we did not collect data on invertebrate abundance and therefore cannot determine the relationship between invertebrate feeding and availability. We conclude that flexibility in consuming diverse food types and food species, and in responding to the availability of preferred foods, has enabled the Cao Vit gibbon to survive in a degraded karst forest habitat.  相似文献   

2.
The Cao Vit gibbon (Nomascus nasutus) was rediscovered in 2002 in Vietnam and then in 2006 in China. This is the only known population with about 110 individuals located along the China-Vietnam border. Little is known about it other than its population size and distribution. We describe the social structure and group dynamics of the Cao Vit gibbons in China based on 2 years of monitoring from 2007 to 2009. Four established study groups at this site consisted of 1 adult male, 2 adult females and 2-6 offspring. Two juveniles in 2 groups disappeared during the research. Four infants were born in 3 groups from November 2008 to February 2009. In 2 of the groups, both adult females had dependent infants. These observations suggest that Cao Vit gibbons live in polygynous groups, contrary to the usual monogamous group with only 1 adult female, but nevertheless similar to the social organization of both N. concolor and N. hainanus. We observed a coordinated dispersal of 1 adult male and 2 large juveniles, and the male formed a pair with a newly arrived female. Our observations support a growing awareness of variability in gibbon social organization.  相似文献   

3.
We studied the sleep‐related behavior of two Cao Vit gibbon (Nomascus nasutus) groups in Bangliang Nature Reserve in Jingxi County, China between January 2008 and December 2009 to test four hypotheses related to sleeping tree selection (predation avoidance, thermoregulation, food access, and range defense). Gibbons entered sleeping trees 88 ± SD 37 min before sunset before their main potential nocturnal predator become active. They usually moved rapidly and straight to sleeping trees and kept silent once settled. Over the course of the study, gibbon groups used many (87 and 57 per group) sleeping trees and reused them irregularly. They also tended to sleep in relatively tall trees without lianas, choosing small branches close to the treetop. These behaviors would make it difficult for potential terrestrial predators to detect and approach the gibbons. Therefore, these results strongly support the predation avoidance hypothesis. Gibbons tended to sleep closer to ridges than to valley bottoms and they did not sleep at lower elevations in colder months. They thus appeared not to select sleeping trees to minimize thermoregulatory stress. Gibbons very rarely slept in feeding trees, instead generally sleeping more than 100 m away from the last feeding trees of the day or the first feeding tree of the next morning. These patterns led us to reject the food access hypothesis. Lastly, we did not find evidence to support the range defense hypothesis because gibbons did not sleep in overlap areas with neighbors more often than expected based on the proportion of overlap and exclusively used areas. Am. J. Primatol. 74:998‐1005, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

4.
Summary The leaf-monkey Presbytis johnii has been found to exhibit considerable selectivity in its dietary utilization of mature foliage in a rain-forest habitat. To investigate the basis of this selectivity and to examine the hypothesis that the observed selection is related to the digestibility and toxicity of the available foliage, chemical analyses have been made on 16 of the most important tree species in the monkey's habitat. It has been found that the most heavily used items, which form a staple part of the diet of P. johnii, are characterized by a low fibre content and a very low condensed tannin content. However, neither class of compound is an absolute feeding deterrent as minor, but still significant, mature leaf food items contain considerable amounts of both. It is suggested that the feeding deterrents in these minor items, which may be ingested to supply specific dietary requirements, can perhaps be tolerated because of their dilution in the gut by the dietary staples. An examination of the pepsin/cellulase digestibility of available mature foliage showed that the staple food items tended to be highly digestible. Little correlation has been found between alkaloid content and food selection and it is suggested that the colobine forestomach microflora has the ability to detoxify at least some alkaloids. Additional data on mature leaf petioles and young leaves suggest that the high ratio of cell-sap to cell-wall in these items, and their related high digestibility, explain the high relative abundance of these items in the P. johnii diet.  相似文献   

5.
K. M. Kool 《Oecologia》1992,90(4):527-533
Summary Samples of leaves and fruits exploited as food items byTrachypithecus auratus sondaicus were analysed for nitrogen content, acid detergent fibre (ADF), pepsin cellulase digestibility (CDIG), condensed tannins (CT), total phenolics (TP) and protein precipitation capacity (PP) and compared with fruits and leaves not eaten. Differences in chemical measures for items eaten and not eaten were not statistically significant but trends indicate that leaves may have been selected for their lower fibre content and greater digestibility. Fruits eaten also had a higher mean level of CDIG and lower mean level of ADF than fruits not eaten but these measures are not considered to be of major importance in fruit selection as CDIG was lower and ADF higher in fruits eaten than in leaves eaten. Levels of CT, TP and PP capacity were higher in fruits eaten than in fruits not eaten but lower in leaves eaten than in leaves not eaten. The role of tannins and phenolics in food selection is discussed. Leaves (and fruits) were not strongly selected on the basis of protein content. Approximately half the dietary intake ofT. auratus sondaicus was leaves, a protein-rich food source. Possibly, protein levels in foliage at Pangandaran were sufficient that selection for this nutrient was not required. A nutrient other than protein (for example, soluble carbohydrates) may have been maximised through food selection. The protein/ADF ratio may provide an indicator of the acceptability of foliage in a habitat as potential food for a colobine. However, this ratio did not govern food selection byT. auratus sondaicus at Pangandaran.  相似文献   

6.
Black colobus monkeys (Golobus salanas) in the Douala-Edea Reserve, a rain-forest on the coast of Cameroon, have been shown to avoid young and mature leaves of most of the common plants in their habitat and to feed disproportionately heavily on leaves of rare plants. The proportion of leaves in the diet was low compared to most colobines studied, and the monkeys spent over half their feeding time eating seeds. Patterns of food selection were analysed in relation to distribution of nutrients, digestion–inhibitors and toxins in the vegetation. Colobw satanas select food items that are rich in mineral nutrients and nitrogen and low in content of the general digestion-inhibitors, lignin and tannin. They achieve this in the following ways: (i) by feeding preferentially on young leaves, which have higher nutrient content and lower contents of digestion-inhibitors than mature leaves; (ii) by eating those mature leaves with highest nument content relative to content of digestion-inhibitors; and (iii) by eating seeds, which are sources of readily available energy and which, as an item class, are less rich in digestion-inhibitors. Seeds at Douala-Edea appear to contain Ins nitrogen than leaves and C. satanas selects those seeds with highest nitrogen content. It is suggested that seed-feeding may be facilitated by the ability of the forestomach flora of these ruminant-like monkeys to detoxify some of the secondary compounds contained in seeds. Avoidance of most unused young and mature leaf items is correlated with a low nutrienudigestion-inhibitor ratio; avoidance of most unused seeds could be accounted for by their low nitrogen contents. Most items whose avoidance could not be explained in terms of these major constraints on food selection possess secondary compounds likely to be toxic. It is proposed that relative importance of digestion-inhibitors, low nutrient content and toxins as constraints on food selection by generalist herbivores will vary greatly among forests with different nutrient and secondary chemistry profiles.  相似文献   

7.
Julie J. Calvert 《Oecologia》1985,65(2):236-246
Summary Samples of stems, leaves, shoots and fruit (N=36) from lowland, African rain forest are analyzed for nutrients, digestibility and digestion-inhibiting substances. Plants from which the samples are drawn are all important in the diet of western gorillas, large generalist herbivores in coastal Cameroon. Many of the plants are common in the early succession following disturbance to the forest. Analysis of food chemistry in relation to food preference indicates that lignin, digestibility and crude protein are the most significant factors in food selection for western gorillas at this site. Food chemistry of western gorillas is compared to food chemistry of mountain gorillas in the montane forest of East Africa. Foliage consumed by western gorillas contains more condensed tannin than does foliage consumed by mountain gorillas. The greater content of condensed tannin in the leaves consumed by western gorillas is related to the greater representation of woody plants in the western diet.  相似文献   

8.
The diets of the banded leaf monkey ( Presbytis melalophos ) at Kuala Lompat in the Krau Game Reserve of West Malaysia and the red leaf monkey ( Presbytis rubicunda ) in Sepilok Virgin Jungle Reserve, Sabah, East Malaysia have been examined in relation to plant chemistry. Both monkeys spent about half their time eating foliage, and about half their time eating fruits and seeds. They both favoured leaves with high digestibility (due to relatively low levels of fibre) and high levels of protein, a combination found predominantly in young leaves and some flowers. The monkeys appeared to favour seeds and fruits with high concentrations of storage carbohydrates or fats, but not those rich in simple sugars. Selection of seeds and fruits was not correlated with protein content.
An analysis of the fibre and protein contents of foods showed that, on an annual basis, the two monkeys achieved a comparable intake for both items. However, these diets were obtained in radically different ways. Presbytis melalophos was able to eat foliage from many of the common tree species in its home range, whereas P. rubicunda relied on rare trees and lianas. This difference is attributed to the very high density of Dipterocarpaceae at Sepilok, a tree family that provides little food for colobines. The rarity of P. rubicunda's food plants at Sepilok is considered to be the main reason for the greater home range size and lower population density in comparison to P. melalophos.
Finally, the biochemical profiles of the young leaf diet of these two monkeys were compared with previously published information on two African and one south Indian colobines. In many respects the intake of supposed critical components, protein and fibre, showed marked similarities between different animals, considering contrasts in their habitats.  相似文献   

9.
Abstract.  Phenotypic flexibility in food selection and digestive efficiency in response is examined in relation to variations in food quality in a detritivorous species of Mediterranean ecosystems, the woodlouse Porcellio laevis Latreille (Isopoda: Oniscidea). It is hypothesized that diet selection should show a positive correlation between diet quality and digestive efficiency. The studied plants are isocaloric but exhibit significant differences in terms of nitrogen, carbon and fibre content. The observations appear to support the hypothesis that these isopods show compensatory feeding behaviour when feeding on poor diets. Contrary to expectation, a dietary effect on relative growth rate is not observed. It is concluded that behavioural skills associated with diet selection and physiological flexibility may allow P. laevis to satisfy and maintain equivalent nutritional levels during exposure to different diet qualities. In general, it appears that physiological flexibility plays an important role in determining nutritional balance in P. laevis , which can be of great benefit in the highly seasonal environment that it inhabits.  相似文献   

10.
Food plant selection by reindeer during winter in relation to plant quality   总被引:5,自引:0,他引:5  
The relative palatabilities of nine plant taxa used as winter food by reindeer were estimated by presenting them in cafeteria and pairwise tests Feeding p reference indices were then related to the chemical composition of the plants High preference indices were obtained for the lichens Bryoria spp, Cladina arbuscula, C rangiferina and C stellaris, while low values were obtained for the moss Pleurozium schrebel and the dwarf shrubs Empetrum hermaphroditum and Vaccinium myrttllus The grass Deschampsia flexuosa and the lichen Stereocaulon paschale received intermediate scores Feeding preferences showed a strong negative correlation with acid detergent fiber (ADF)-values No statistically significant correlations were found between feeding preferences and contents of nitrogen, in vitro organic matter digestibility (IVOMD) or neutral detergent fiber (NDF)  相似文献   

11.
The food selection and diet of juvenile three-spined sticklebacks (Gasterosteus aculeatus L.) was studied in the littoral of a brackish-water sea area. The sampling stations were located in a eutrophicated area, where the plankton was characterized by rotifers, in a noneutrophicated zone, where copepods predominated, and in the intermediate zone, characterized by cladocerans. In all areas the fish preferred microcrustaceans to rotifers, but they did not feed strictly according to the size-selection hypothesis. Nor did they take the most abundant prey species. With some exceptions the species chiefly eaten by and also selected by fish, were those which had the largest biomass in the plankton.  相似文献   

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14.
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  
范朋飞 《兽类学报》2012,32(3):248-258
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   

15.
药用植物数据库的建立与相关数据挖掘,对民族药物学的研究具有重要意义。该研究在顶层设计的基础上,对广西靖西端午节药市及周边地区实地调查时获得的药用植物标本和照片进行形态学特征、药用价值、民族传统利用方式等信息的整理,由此设计和建立开放的民族药用植物数据库系统。主要应用Microsoft Office Access和Java编程对数据进行管理、查询和统计,通过提取药用植物特征的不同权值来计算不同科属和类别之间的相似度。结果表明:该数据库系统能以柱状图或饼状图的形式将数据之间的关系直观地展示出来,从而反映出各种植物特征和各种功能属性之间的联系。同时该数据库系统还可以用于数据的管理、检索和查询相关民族药用植物的背景资料、药用价值等信息,并能进行相应的统计分析,有利于挖掘数据和发现新线索。  相似文献   

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17.
The moose (Alces alces cameloides) population in northeastern China is on the southernmost edge of its distribution in Asia. A survey was conducted to determine moose resource selection and the effects of human disturbance on moose in a study area of 20,661 ha located on the northwestern slope of the Lesser Khingan Mountains, located in northeastern China. Predictive models of resource selection were developed using logistic and autologistic regression. All models considered resource variable selection at two spatial scales, patch and landscape. At the patch scale, moose preferred larger birch (Betula platyphylla) patches, but avoided larger tamarack (Larix gmelinii) patches. At the landscape scale, moose preferred higher densities of tamarack patches, i.e., heterogeneity of tamarack stands, selected areas with more abundant annual shoots, terrain conducive to better concealment, higher altitudes and areas saturated with soil moisture. Roads and forest harvest intervals were identified as important human disturbance factors. This is the first time that moose have been reported to avoid roads, and the avoidance distance was nearly 3 km. We believe that in this region moose under the influence of roads are behaviorally plastic, compared with the indifference of moose to the presence of roads in other regions. Moose avoided forest areas logged more than 3 years previously and preferred areas logged 1–2 years previously. In addition, it may be necessary to monitor the effect of the dynamic of density of roe deer on the spatial distribution of the moose population.  相似文献   

18.
In various vegetation types in Zimbabwe, the catches of Glossina pallidipes Austen and G. morsitans morsitans Westw. (Diptera: Glossinidae) at a target baited with odour (acetone, 1-octen-3-ol and two phenols) were positively correlated with catches of the same species at an unbaited net. No correlation existed between target catches and hand net catches of tsetse flies sitting on the vegetation. G. pallidipes females caught at a target and at an unbaited net were older than those caught from vegetation. Of the female G. pallidipes caught at the target, 46% were in the first 3 days of pregnancy. Of those caught at the unbaited net, significantly fewer, 21%, were in this stage. G. pallidipes males caught from vegetation contained more fat (3.07±0.333 mg) than those caught at the unbaited net (2.06±0.339 mg) or at the target (2.19±0.218 mg). It is inferred that target catches consisted predominantly of tsetse which were already in flight when they sensed the stimuli from the target, and that target catches were biased towards female G. pallidipes in the first 3 days of pregnancy.  相似文献   

19.
广西靖西西南桦天然林种子雨的时空动态   总被引:2,自引:0,他引:2       下载免费PDF全文
以一片西南桦(Betula alnoides)天然林和一个西南桦独立单株为研究对象, 通过收集散种期内与林分或母树不同距离的种子以及测定风速和风向, 研究了西南桦群落和个体水平上种子雨的时空动态及其与风速和风向的关系。结果表明: 群落水平上, 西南桦种子散布的初始期、高峰期、消退期分别历时11天、32天和40天, 而个体水平上则为9天、25天和26天。高峰期内群落和个体水平的散种量分别占其总量的83.1%和68.7%, 而且白天的种子雨密度高于夜间; 西南桦个体白天种子雨密度最大的时段为12:00-16:00, 与此时段内风速较高有关。在个体水平上, 距离母树0-30 m范围内散落的种子占总散种量的79.6%; 而在群落水平上, 距离林缘0-45 m范围内集中了总散种量的81.2%。西南桦种子散布具有方向性, 无论个体还是群落水平上不同方向间种子雨密度差异极显著(p < 0.01), 与散种期内的主要风向有关; 而且种子雨密度与风速亦呈极显著正相关关系。研究结果将有助于揭示西南桦天然更新动态和更新机制, 亦为开展西南桦人工促进天然更新提供理论依据。  相似文献   

20.

Information

Taxonomy, distribution, and status of gibbons (Hylobates) in Southern China and adjacent areas  相似文献   

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