首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Previous studies of Trachypithecus species indicated that they were selective feeders that concentrated on relatively few food species/items. From January to December 2005, I quantified potential food availability and the food species/items eaten by five groups of François' langur (Trachypithecus francoisi) in the Mayanghe Nature Reserve (MNR), People's Republic of China. These langurs fed on 164 species, of which the top ten accounted for 51% of all feeding records. Langurs consumed more species (91) in the spring than in other seasons (73 summer, 75 autumn, and 67 winter), and only 38 species were consumed in all seasons. Nontree food species, such as bushes and lianas, accounted for 47% of the total feeding records and for a majority (68%) of the feeding records in winter. The annual diet consisted of leaves (64% of feeding records), fruit and seed (32%), and other nonfoliage items (4%); the langurs switched from being more folivorous in spring (93%) and summer (79%) to being more frugivorous in autumn (53%) and winter (56%). There was no correlation between the proportion of feeding records and the food availability in the most frequently consumed species, indicating that these langurs were selective feeders; there were significant correlations between consumption and abundance in both the entire set of 112 food species and the set of 86 infrequently consumed species, indicating that foods that are more available are eaten more frequently. It appeared that in the seasonal and disturbed habitat, feeding decisions and diet composition of the langur may be driven more by food availability, and less by animal's selectivity, than at other sites. The results indicate that François' langur copes with habitat alterations by broaden its dietary breadth; this has implications for the adaptive significance of dietary breadth, and has implications for future conservation strategies for species which exist in degraded habitats. Am. J. Primatol. 73:1176–1187, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   

2.
We studied the locomotor behaviour of white-headed langurs Trachypithecus leucocephalus and Franois' langurs T.franoisi to test two hypotheses:(1) these monkeys have evolved locomotor ability to support their activities on limestone hills,and (2) Franois' langurs have evolved more diverse locomotor skills than white-headed langurs. Data were collected from 1996-1998 and in 2005 in Fusui Nature Reserve,Guangxi,and showed that the two species had similar locomotor types,but Franois' langurs had more locom...  相似文献   

3.
This paper discusses the taxonomy and distribution ofPresbytis francoisi. We are especially concerned with the classification of the white-headed langur.T'an (1957) suggested that the white-headed langur be classified as a separate species,Presbytis leucocephalus. We suggest that the white-headed langur is a subspecies ofPresbytis francoisi and should be referred to asP. francoisi leucocephalus. The distribution of the six subspecies of the françois' langur,P. f. delacouri, P. f. francoisi, P. f. hatinhensis, P. f. laotum, P. f. leucocephalus, andP. f. poliocephalus, is limited to southeastern Asia.  相似文献   

4.
5.
Data on activity budgets and ranging patterns were collected from March to December 2001 for one group of François’ langurs (Trachypithecus francoisi) inhabiting a forested part of the Fusui Nature Reserve, Guangxi province, China. Our results indicate that the total size of the home range of the study group during the study period was 19 ha. The majority of their activities (52%) occurred within a small area, 22%, of their home range, and was concentrated in or near quadrats containing their sleeping sites, which may reduce the time and energetic cost of travel. The extent of the ranging behavior varied between months, with the smallest, 7 ha, recorded in July and the largest, 13.5 ha, in November. There was no significant difference between seasons. The monthly mean daily path lengths varied from 341 to 577 m. The daily path lengths showed significant seasonal changes: the path lengths were longer during the dry season than in the rainy season, which may be related to the scarcity of preferred food resources during the dry season.  相似文献   

6.
7.
The anatomical and histological structure of the stomach was examined in François' leaf monkeys (Presbytis francoisi). The stomachs consisted of three parts, the saccus, the tubus gastricus and pars pylorica, and had well-developed taeniae and many haustra. The cardiac gland region occupied the saccular forestomach and the anterior half of the tubus gastricus, while the fundic gland region occupied the posterior half of the tubus gastricus. The pyloric gland region occupied the entire pars pylorica. In the mucosa of the cardiac gland region, villus-like processes were observed. The mucosae of the cardiac and pyloric gland regions contained not only neutral mucins but also acid mucins.  相似文献   

8.
The Health Care Ethics Consultant marks a stage in the development of ethics consultancy. Ethics consultancy is a manifestation of a newly secularized society in which a new discipline has developed to fill a gap created by the combination of the diminishing influence of traditional moral authorities and the growth of new problems associated with the development of new technology and changes in society and culture. The stated primary objective of the book is to focus attention on an immediate practical problem: the role and responsibilities, the education and training, and the certification and accreditation of health ethics consultants. An edited collection of articles, the book originated as a research project financed by the Social Sciences and Humanities Research Council of Canada, undertaken by a Strategic Research Network which included faculty members from Dalhousie University, McGill University, the University of Toronto, McMaster University and the University of Calgary.  相似文献   

9.
10.
We studied the ecology of white-headed langurs (Trachypithecus leucocephalus) in Fusui Precious Animal Reserve, Guangxi, China, in 1997/1998 and conducted surveys of them in 1996–1997 and 2003. We collected data on vegetation fragments and the activities of white-headed langurs at different levels on limestone hills. The langurs selected less fragmented habitats with less human disturbance. They spent ca. 60% of the day at lower levels of the hills during maintenance activities, including feeding. When humans were absent, the langurs even came to the ground. The hills themselves were used as a refuge from human disturbance but were not otherwise essential habitat. Results of this study have implications for improving conservation management for the langurs.  相似文献   

11.
Abstract: A total of 175 spotted snapper Lutjanus guttatus were collected monthly in the Los Cobanos and Puerto La Libertad, El Salvador, from January to December 2000 to determine its feeding habits. The fishes studied ranged 9.8 - 58.0 cm in total length. Were collected using push-net and hook and line. This snapper is a bentonic opportunistic carnivorous predator. The total biomass of the stomach contents was 260.5 g. Crustaceans (Squillidae, Portunidae, Dynomenidae. Penaeidae, Sicyoniidae, Callianassidae), were the most abundant group: they accounted for 50.4% of the total biomass. Numerically, Portunus asper was the most abundant prey. Ontogenic differences were observed in the diet. In juveniles (16 cm TL). at any time of the year, the most frequent and abundant components were crustaceans and in adults were crustaceans, fishes and mollusks. The relative importance of different components of the diet was assessed with two indexes that combine. in different ways. percentage frequency of occurrence, percentage number and percentage weight of prey categories. The commercial use this resource and the absence of management strategies are discussed.  相似文献   

12.
The Southern Espinha?o Range consists of large areas covered by quartzitic or metaliferous tropical altitudinal fields. The Espinha?o Range ecosystems are endangered by anthropic high impacts, particularly due to mining and urbanization. We conducted a one-year inventory of the bee flora and fauna at the quartzitic Ouro Branco Mountains and a two-year survey of the metaliferous Ouro Preto fields. The samples were collected twice a month, from 8:00 am to 5:00 pm. The bees (677) belonged to 91 species, five families. The family Apidae was the richest and most abundant, followed by the Halictidae and Megachilidae. The bees visited 46 flowering plant species; the most visited plants were the Asteraceae (n = 220), the Malpighiaceae (n = 95), the Melastomataceae (n = 94), the Fabaceae (n = 78), and the Solanaceae (n = 63). Diversity was higher in Ouro Branco (H = 1.47) than in Ouro Preto (H = 1.17). The low richness and abundance of bees in our research site when compared to other Brazilian "Cerrado" areas can be due to the high altitude, low temperature, and low availability of flowers we found. "Canga" and rupestrian areas house fauna and flora species that are rare and threatened by extinction. The southern Espinha?o areas can, therefore, be given the status of permanent biodiversity preservation area.  相似文献   

13.
Synopsis The feeding ecology of three characids (A. fasciatus, A. bimaculatus and A. schubarti) was studied monthly during 1988 in Lake Inferñao, a major floodplain lake of the Mogi-Guaçú River in the State of São Paulo. River flooding directly influenced the diet of the omnivorous A. bimaculatus and A. fasciatus which responded to maximum inundation (March) by consuming predominantly allochthonous insects. In contrast, A. schubarti was less influenced by the river flood cycle on qualitative changes in diet and relied basically on aquatic macrophytes and periphytic algae. The importance of zooplankton in the diet of the three species was low, and may be attributed to its low density in the water column (< 1 ind l–1). Ontogenetic diet changes were evident for the three species. For A. fasciatus and A. bimaculatus the importance of zooplankton was high at the early stages, decreasing with size. A. schubarti at younger stages consumed diversified items which gradually decreased quantitatively up to the size class of 65 mm; from this size onwards, the diet became restricted to the consumption of periphytic algae and macrophytes.  相似文献   

14.
The effects of the fruit ripening mutant gene alcoba?a (alc) and color development mutants, old gold-crimson (ogc) and high pigment (hp), on yield and post-harvest quality of tomato fruits were investigated. Five tomato hybrids were obtained by crossing near isogenic lines with Flora-Dade background [Flora-Dade (alc+/alc+ ogc+/ogc+ hp+/hp+), TOM-559 (alc/alc ogc+/ogc+ hp+/hp+), TOM-591 (alc/alc ogc/ogc hp+/hp+), TOM-593 (alc/alc ogc+/ogc+ hp/hp), and TOM-589 (alc/alc ogc/ogc hp/hp)] with the pollen parent line Mospomorist (alc+/alc+ ogc+/ogc+ hp+/hp+). Hybrid fruit was harvested at the breaker stage and stored on shelves at 15oC and 60% relative humidity for 16 days, and then evaluated for firmness, development of red color, and carotenoid contents. The different genotypic combinations at the loci alc, ogc and hp had no effect on fruit yield. The alc+/alc hybrid genotype significantly increased fruit firmness and significantly delayed the development of red color in maturing fruit. Simultaneous usage of ogc+/ogc and hp+/hp promoted an increase in the red color and lycopene content of alc+/alc hybrids, but did not have any additional effect on fruit firmness.  相似文献   

15.
Wild animals increasingly inhabit human-influenced environments such as forest fragments amid agricultural systems. Dietary studies provide a means of assessing wildlife responses to anthropogenic habitat changes. Chimpanzees are specialist frugivores that consume other plant parts, e.g., fibrous pith and leaves, in greater amounts during fruit shortages. I examined the plant diet and seasonal foraging strategies of chimpanzees inhabiting small forest fragments within a cultivated landscape in Uganda. I determined diet over 13 mo via systematic fecal analysis, supplemented by direct observation and feeding trace evidence. I identified important foods and examined their role as seasonal fallbacks. Diet composition and breadth were overall species typical. Chimpanzees were highly frugivorous and the fruit component of fecal samples exceeded that of nonfruit fiber in all months. Forest fruit availability fluctuated seasonally, including a 3-mo low fruiting season, when overall fruit intake declined. During this time chimpanzees pursued a mixed strategy of increasing fiber consumption and feeding more heavily on energy-rich cultivars, including those obtained through crop raiding. The data suggest that exploiting agricultural fruits helped chimpanzees maintain a fruit-dominated diet when forest fruit was scarce. No evidence suggested this disturbed forest–farm mosaic is a food-impoverished habitat for chimpanzees overall. Nevertheless, cultivar feeding creates conflict with people and the high nutritional quality of crops is likely offset by the inherent risk associated with obtaining them. This study adds to growing evidence of ecological and behavioral adaptability of Pan troglodytes in response to anthropogenic habitat alteration. Targeted conservation of key natural foods for wildlife —particularly fallbacks— would help reduce conflicts and improve the survival prospects of threatened species sharing environments with people.  相似文献   

16.
Monthly collections were made of man‐biting female blackflies: Simulium auripellitum Enderlein, S. guianense Wise, S. minusculum Lutz and S. nigrimanum Macquart (Diptera: Simuliidae) from four catching stations in the newly discovered focus of human onchocerciasis at Minaçu (13°35′ S 48°18′ W), 300 km north of Brasília in Goiás State. These provided baseline data on biting habits, population density and seasonal prevalence during the year before completion of the Serra da Mesa hydroelectric dam on the Rio Tocantins near Minaçu, in a project investigating the effect of dam construction on onchocerciasis transmission in the area. All four simuliid species were most abundant during the dry season, and only bit in low numbers (S. auripellitum S.minusculum, S. nigrimanum) or were absent (S. guianense) in the wet season. Simulium minusculum was the predominant species at all catching stations, being particularly abundant by the large River Tocantins. The other three species were mainly associated with smaller rivers. In the dry season, biting rhythms of S. minusculum varied with catching site, while S. nigrimanum showed peaks of activity in early morning and during the afternoon. Experimental infection with Onchocerca volvulus (Leuckart) (Nematoda: Onchocercidae), from a human volunteer, showed that this parasite could develop fully in the four simuliid species, which are all considered to be potential vectors in the area.  相似文献   

17.
This is the first record of the presence of the medically important genus Lutzomyia Fran?a in the Department of Guainía, Colombia. Sand flies were collected biting humans in the surroundings of the urban area of the Municipality of Inírida. Three Lutzomyia species were taxonomically identified as L. davisi (Root), L. olmeca bicolor Fairchild & Theodor, and L. antunesi (Coutinho). Additionally, Brumptomyia mesai Sherlock is cited for the first time in the Caribbean Coast of Colombia based on specimens collected with a modified CDC light trap in the Reserva Forestal Protectora Serranía de Coraza y Montes de María, Department of Sucre.  相似文献   

18.
Lowland rain forest chimpanzees (Pan troglodytes verus) of the Taï National Park, Ivory Coast, responded to the minor dry season (July and August) of 1988 in a predictable manner by spending more time feeding, feeding more frequently on lower quality food items, reducing day range and party size, and spending more time solitarily and less time in mixed groups than during the rainy season. These behaviors are consistent with a response to scarce resources. My findings do not support Boesch's (1991, 1996) hypothesis of bisexually bonded chimpanzees. Females spent 45% of time alone and associated with males in mixed parties only 18% of their time. This major discrepancy in our results probably stems from differences in the time of year when our studies were conducted, the year in which my study was conducted (potentially scarcer resources than on average), and methodological differences: focal animal sampling of males and females equally. Although Boesch (1991, 1996) and Steiner (1996) have demonstrated that Taï parties are usually larger and more mixed, Taï chimpanzee social structure—party size and composition—during this study closely resembles that found at other study sites.  相似文献   

19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号