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21.
The study on the population status and human impacts on the endemic and endangered Swayne’s hartebeest (Alcelaphus buselaphus swaynei) was carried out in Nechisar Plains, Nechisar National Park, between 2009 and 2010. Direct and total count methods were applied in the population census. Data collected since 1967 were also examined to indicate trends of Swayne’s hartebeest populations and their translocation status. In eight illegal Guji Oromo settlements, a total of 134 household samples were identified for group discussion and interview. A trend on livestock population was carried out. The total count of Swayne’s hartebeest was 12, 11 and 12 during the 1st, 2nd and 3rd counts, respectively. The population has been decreasing and nowadays only 12 individuals remain. Most respondents had a negative attitude towards conservation areas. The increase in livestock population from 1985 to 1996 was 47.8%. It also increased by 49.9% and 56.5% during 2006 and 2010, respectively. There were 12,531 heads of livestock that depended on the grass plains illegally. Overstocking rate of livestock, illegal resource exploitation and loss of wildlife habitat were the major problems encountered. Active measures have to be implemented to control the human impact and safeguard the future of Swayne’s hartebeest. 相似文献
22.
Toshitaka Iwamoto Akio Mori Masao Kawai Afework Bekele 《Primates; journal of primatology》1996,37(4):389-397
The anti-predator behavior of gelada baboons has been observed to consist of simple flight (i.e. they flee to cliffs after
becoming alarmed by potential predators). However, active antipredator behavior was observed in a recently found gelada population
in Arsi, Ethiopia. This population showed frequent active counter-attacks and severe mobbing at predators. Males fought domestic
dogs on the plain and exhibited a systematic mobbing behavior towards a leopard on the cliff face to chase it off. These active
anti-predator behaviors are the first confirmed reports on gelada baboons and may provide a useful insight for the understanding
of the process of evolutionary adaptation to highland habitats by gelada baboons, as well as for the origin of this small
southern population. 相似文献
23.
Occurrence, seasonality and genetic diversity of Vibrio vulnificus in coastal seaweeds and water along the Kii Channel, Japan 总被引:1,自引:0,他引:1
Mahmud ZH Neogi SB Kassu A Mai Huong BT Jahid IK Islam MS Ota F 《FEMS microbiology ecology》2008,64(2):209-218
Vibrio vulnificus is a ubiquitous toxigenic bacterium found in a coastal environment but little is known about its occurrence and seasonality among seaweeds, which are widely consumed as seafood in Japan. Therefore, we have observed the bacterium's abundance in seawater and seaweed samples from three areas of the Kii Channel, Japan, during June 2003 to May 2004. A total of 192 samples were collected: 24 from each source in summer, autumn, winter and spring. The samples were selectively cultivated following the most probable number (MPN) technique. Vibrio vulnificus population ranged from 0 to 10(3) MPN 100 mL(-1) seawater or 10 g seaweeds; higher counts were observed during summer. The optimum temperature, salinity and pH for the bacterium were 20-24 degrees C, 24-28 p.p.t. and 7.95-8.15, respectively. However, seaweeds always contained higher V. vulnificus than seawater. Among 280 V. vulnificus strains, detected by species-specific colony hybridization and PCR, 78, 74, 11 and 16 were from seaweeds and 46, 42, 2 and 11 were from seawater during summer, autumn, winter and spring, respectively. Ribotyping of 160 selected strains revealed a higher genotypic diversity (18 patterns) among strains from seaweeds than from seawater (10 patterns). Seaweeds can thus act as a potential habitat for V. vulnificus and are more unsafe for consumption during summer. 相似文献
24.
Anagaw Atickem Stuart Williams Afework Bekele Simon Thirgood 《African Journal of Ecology》2010,48(4):1076-1082
In the Web Valley of the Bale Mountains National Park, the pastoral people suffer from livestock predation by wild carnivores. A total of 704 livestock were reported to be killed by wild carnivores over a 3‐year period, causing a loss of potential revenue of 12 USD per year per household. Reported annual predation rates equated to 1.4% of the livestock population of the study area. Spotted hyaenas were responsible for most livestock predation (57%), followed by leopards (18%), common jackals (16%) and servals (9%). Hyaenas killed all livestock types (horses, donkeys, mules, cattle, goats and sheep) whilst leopards, common jackals and servals killed mostly goats and sheep. A survey of 362 households revealed that the pastoral people keep dogs to protect livestock from carnivores. During 250 nights of observation in the ten settlements, pastoralists were alerted to the presence of hyaenas on 80 occasions by the barking of their dogs. Such tradition of keeping dogs presents a threat to the persistence of the endangered Ethiopian wolf through diseases transmission. Given the frequency of carnivore attacks on livestock, it is desirable to develop alternative livestock protection methods that both minimize livestock losses and reduce the risk of disease transmission to Ethiopian wolves. 相似文献
25.
Population structure and group size of geladas (Theropithecus gelada) at Chenek,Simien Mountains National Park,Ethiopia 下载免费PDF全文
The aim of this study was to investigate population structure and group size of geladas (Theropithecus gelada) at Chenek, Simien Mountains National Park. The study was carried out from January 2010 to June 2011 using total count method by classifying the study site into five different blocks. Size of the group was determined by counting individuals of geladas within an hour interval. A total of 397 geladas were counted and the ratio of adult males to adult females was 1 : 1.25, and this difference showed statistical significant (t = 8.157, P < 0.05). There was also significant difference between adult females with juveniles and infants (t = 21.027, P < 0.05). Population structure of geladas in a band comprised a single reproductive male and a number of females, subadults, juveniles and infants. Fission and fusion of individual geladas among different bands were observed during the study period. Geladas at the study site showed population growth and were seen competing for available food. They also stole food from local people and tourists and were seen to be interactive with people. Thus, the interference of people and livestock within the geladas natural habitat should be minimized to avoid human disturbance on the species and its natural habitat. 相似文献
26.
We studied the population dynamics of endangered mountain nyala Tragelaphus buxtoni between 2003-2005 in the Bale Mountains National Park. Line-transect sampling and total count methods were used to gather data on demographics and movement patterns. The population's age-group composition was 58% adults, 25% sub-adults, 9% juveniles, 5% calves and 3% unidentified with a female-male sex ratio of 2:1. Population density was found to be significantly different between the two sub-populations (Dinsho Sanctuary a... 相似文献
27.
To understand habitat preferences, seasonal abundance and diets of rodents in wet and dry season surveys were conducted in Alage, Southern Ethiopia. Sherman and snap traps were used to capture rodents from the four habitats: bushland, Acacia woodland, maize and wheat farmlands. A total of 3312 trap nights, from the four trapping habitats, yielded 776 individuals that represented 11 species of rodents. The distribution of rodents varied between habitats and seasons. Wet season rodent abundance was 52.3% while in the dry season it was 47.7%. Seasonal differences in species abundance were insignificant. Bushland habitat had high wet and dry season abundances with 137 and 211 individuals, respectively. Abundance was low in maize farm (57 individuals) in the wet season and wheat farm (10 individuals) in the dry season. Stomach content composition analysis of snap‐trapped rodents from different habitats showed differences between species and across seasons. Six rodent species were recorded as pests on the farmlands in this study area. In conclusion, variation in habitat preferences and diet of rodents in different habitats and across seasons might be due to the role of ground cover and food sources. 相似文献
28.
To document the species composition, relative abundance and habitat association of small mammals, wet and dry season surveys were conducted along the altitudinal gradient of Jiren Mountain, Jimma area, Ethiopia. Sherman traps were used to capture small mammals from the six habitats: wetland, mixed plantation, open shrub, eucalyptus plantation, montane grassland and coffee plantation. The 393 trap nights, from the six habitat types, yielded 106 individual small mammals of tweleve species. The trapped rodents were Lophuromys flavopunctatus, Stenocephalemys albipes, Desmomys harringtoni, Mus mahomet, Lemniscomys barbarous, L. striatus, Tachyoryctes splendens, Mastomys natalensis and the insectivores Crocidura fumosa and C. turba. Two species of rodents Hystrix cristata and Helioscuirus gambianus were observed. Lophuromys flavopunctatus and S. albipes contributed 83.8% of the total capture. L. flavopunctatus, S. albipes and D. harringtoni were distributed in all habitats and gradients. T. splendens was captured from montane habitat, while the zebra mice were associated with the lower altitude habitats. Lophuromys flavopunctatus and M. natalensis extended their range deep into the coffee plantation habitats. Uncontrolled vegetation exploitation of the mountains for timber production and fire wood collection are the major threats. Conservation of the area to reduce the anthropogenic pressure is essential. 相似文献
29.
Zouré HG Wanji S Noma M Amazigo UV Diggle PJ Tekle AH Remme JH 《PLoS neglected tropical diseases》2011,5(6):e1210
Background
Loiasis is a major obstacle to ivermectin treatment for onchocerciasis control and lymphatic filariasis elimination in central Africa. In communities with a high level of loiasis endemicity, there is a significant risk of severe adverse reactions to ivermectin treatment. Information on the geographic distribution of loiasis in Africa is urgently needed but available information is limited. The African Programme for Onchocerciasis Control (APOC) undertook large scale mapping of loiasis in 11 potentially endemic countries using a rapid assessment procedure for loiasis (RAPLOA) that uses a simple questionnaire on the history of eye worm.Methodology/Principal Findings
RAPLOA surveys were done in a spatial sample of 4798 villages covering an area of 2500×3000 km centred on the heartland of loiasis in Africa. The surveys showed high risk levels of loiasis in 10 countries where an estimated 14.4 million people live in high risk areas. There was a strong spatial correlation among RAPLOA data, and kriging was used to produce spatially smoothed contour maps of the interpolated prevalence of eye worm and the predictive probability that the prevalence exceeds 40%.Conclusion/Significance
The contour map of eye worm prevalence provides the first global map of loiasis based on actual survey data. It shows a clear distribution with two zones of hyper endemicity, large areas that are free of loiasis and several borderline or intermediate zones. The surveys detected several previously unknown hyperendemic foci, clarified the distribution of loiasis in the Central African Republic and large parts of the Republic of Congo and the Democratic Republic of Congo for which hardly any information was available, and confirmed known loiasis foci. The new maps of the prevalence of eye worm and the probability that the prevalence exceeds the risk threshold of 40% provide critical information for ivermectin treatment programs among millions of people in Africa. 相似文献30.