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Studying the dietary flexibility of primates that live in human‐modified environments is crucial for understanding their ecological adaptations as well as developing management and conservation plans. Southern gelada (Theropithecus gelada obscurus) is an endemic little‐known subspecies of gelada that inhabits human‐modified landscapes in the northern central highlands of Ethiopia. During an 18‐month period, we conducted this intensive study in an unprotected area of a human‐modified landscape at Kosheme in Wollo to investigate the feeding ecology of southern geladas and their dietary responses to seasonal variations. We quantified the monthly and seasonal diet data from a band of southern geladas using instantaneous scan sampling method at 15‐min intervals, and green grass phenology and availability using visual inspection from the randomly selected permanent plots. The overall average diet of southern geladas at Kosheme constituted grass blades 55.4%, grass undergrounds 13.2%, grass bulbs 5.6%, grass seeds 5.4%, herb leaves 4.0, fruits 7.3%, and cereal crops 5.6%. Grass blade consumption increased with increasing green grass availability, while underground food consumption increased with decreasing green grass availability, and vice versa. Southern geladas spent significantly more time feeding on the grass blades and herb leaves and significantly less time on bulbs during the wet season than the dry season. Underground grass items (rhizomes and corms) were not consumed during the wet season, but made up 22.3% of the dry season diet. Thus, although grass blades are staple diet items for geladas, underground diet items are important “fallback foods” at Kosheme. Our result shows insights into the dietary flexibility southern geladas adopt to cope with human‐modified landscapes of the north‐central Ethiopian Highlands. Thus, the study contributes to a better understanding of how changing environments shape primate ecology and evolution. 相似文献
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We investigated the geographic variation of eight Ethiopian populations of the rodent Lophuromys flavopunctatus and compared them to the Bale endemic species L. melanonyx. We used multivariate morphometrics and analysed independently skull and external body linear measurements, in an attempt to relate morphological variability to geography (latitude, longitude, altitude). There is a high morphological diversity in these Ethiopian populations, which form three distinct recognizable groups, with the Bale population being the most distinct. The results of analyses on the two character sets corroborate each other and indicate that the kind of variation is not 'ecological' but rather there is a phylogenetic cause, and relations at higher taxonomic level are suggested. There is a homogeneous group with five populations within which there is a recognizable pattern of clinal variation related to altitude, with a decrease in body size and a change in skull shape. 相似文献
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Pregnant women in developing countries are vulnerable to multiple micronutrient deficiencies. Studies assessing serum levels
of the micronutrients and magnitude of their deficiencies are very scarce in African subjects. This study was aimed at determining
serum levels of micronutrients in 375 pregnant (42 HIV seropositive) and 76 non-pregnant women (20 HIV seropositive) who visited
the University of Gondar Hospital, Gondar, Ethiopia. Serum concentrations of zinc,\ copper, selenium, calcium, and magnesium
were determined using an inductively coupled plasma mass spectrometer. Irrespective of HIV serostatus, pregnant women had
significantly higher serum concentrations of copper and copper/zinc ratio and significantly lower magnesium compared to those
in non-pregnant women (P < 0.05). Except for selenium, which was significantly lower in HIV-seropositive pregnant women (P < 0.05), the mean serum concentrations of zinc, copper, calcium, and magnesium were not significantly different between pregnant
women by HIV serostatus. The prevalence of deficiency in zinc, magnesium, selenium, and calcium in the pregnant women, irrespective
of their HIV serostatus, was 66.7%, 25.6%, 21.9%, and 9.3%, respectively. The magnitude of deficiency in zinc, magnesium,
and selenium was significantly higher in HIV seropositive pregnant women (76.2%, 52.4%, and 45.2%) than that in HIV-seronegative
pregnant women (65.5%, 22.2%, and 18.9%) and in HIV-seronegative non-pregnant women (42.9%, 8.1%, and 30.4%; P < 0.05). Deficiency in one, two, three, or four mineral elements was observed in 44.8%, 14.4%, 9.9%, and 5.1% of the pregnant
women, respectively. Only 25.9% of the pregnant women and 44.7% of the non-pregnant women were not deficient in any of the
micronutrients. The high prevalence of micronutrient deficiencies in pregnant and non-pregnant women in Gondar, Ethiopia warrants
the need for strategies on prevention and control of the deficiencies. 相似文献
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Addisu Mekonnen Afework Bekele Peter J. Fashing Graham Hemson Anagaw Atickem 《International journal of primatology》2010,31(3):339-362
Bale monkeys (Chlorocebus djamdjamensis) are little-known primates endemic to the forests of the Bale Massif and Hagere Selam regions of Ethiopia. From August 2007
to May 2008, we conducted the first ever study of the species’ behavior and ecology, focusing in particular on its diet, activity
patterns, and ranging ecology in the Odobullu Forest. We studied 2 neighboring groups (group A: 55–60 members; group B: 46–50
members) and conducted behavioral scan samples on the first 2–5 individuals sighted at 15-min intervals. Feeding accounted
for 65.7% of the activity budget, followed by moving (14.4%), resting (10.7%), social (7.1%), and other behaviors (2.4%).
Overall diet during the study was dominated by young leaves (80.2%), though subjects also ate fruits (9.6%), flowers (3.1%),
animal prey (2.3%), shoots (1.5%), stems (1.4%), mature leaves (1.1%), and roots (0.9%). Bale monkeys consumed only 11 plant
species; of these, the top 5 species accounted for 94.3% of their diet. The top food item, bamboo (Arundinaria alpina), was responsible for a remarkable 76.7% of their diet, with most (95.2%) of the bamboo consumption consisting of young leaves.
Mean daily path length for the study groups was 928 m and mean (100% minimum convex polygon) home range size was 15.2 ha.
Though we are cautious in drawing conclusions from only 2 groups, the larger group traveled further per day and occupied a
larger home range, patterns suggesting scramble competition may be occurring in Bale monkey groups at Odobullu. The dietary
specialization of Bale monkeys on bamboo makes them unique among Chlorocebus spp. and suggests an intriguing ecological convergence with the golden monkeys (Cercopithecus mitis kandti) of Uganda and bamboo lemurs (Hapalemur spp.) of Madagascar. Their narrow ecological niche, limited geographic distribution, and bamboo harvesting by local people
for commercial purposes place Bale monkeys at risk of extinction. To ensure the long-term survival of Bale monkeys, appropriate
management action should be taken to conserve the species and the bamboo forests upon which it depends. 相似文献
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Girma MENGESHA Afework BEKELE 《动物学报》2008,54(1):20-29
于2004年8月-2005年3月间研究了Alatish国家公园在雨季和旱季期间大型哺乳动物的多样性和分布.基于地形图、卫片和预调查结果,在4种生境类型中识别出37个100 km2或者更小的斑块.在4个植被类型中随机选择了11个斑块,沿随机选择的样线进行了调查,样线10 km 长,0.2 km宽,覆盖了该区域面积的20%.使用Shannon-Wiener多样性指数、DISTANCE 5.0 软件以及 Simpson相似性指数分析了大型哺乳动物的多样性以及分布的相似性.记录了20种体型较大的哺乳动物;河边林地在雨季和旱季都有最高的多样性,林地的多样性最低;旱季中4种类型的栖息地具有相似的分布型;由于栖息地退化不能确定物种的分布格局.联合距离取样分析揭示出,旱季和雨季大型哺乳动物的密度较低,分别为4.067只/km2和6.263只/km2.所观察的哺乳动物可分为草食动物(15%)、游牧动物(30%)、杂食动物(25%)与食肉动物(30%). 相似文献
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Fanuel Kebede Patricia D. Moehlman Afework Bekele Paul H. Evangelista 《African Journal of Ecology》2014,52(4):533-542
The African wild ass (Equus africanus) is the most endangered wild equid in the world and is listed as a Critically Endangered (CR) on the IUCN Red list. Today, only relict populations remain in Ethiopia and Eritrea. The current Ethiopian population persists in the Danakil Desert at a very low density. Wildlife managers need to identify the extent of the remaining suitable habitat and understand human–wildlife interactions for appropriate conservation strategies. This study employed the maximum entropy model (Maxent) to determine suitable habitat and seasonal distribution of African wild ass in the Danakil Desert of Ethiopia. Field surveys were conducted four times annually, twice during the wet season and twice during the dry season, for 2 years. Field data and predictor variables were separated into the dry and wet seasons, and models were generated for each season independently. Distance from water, distance from settlements, herbaceous cover and slope were the best predictors of suitable habitat for both dry and wet seasons. Evaluations of model performances were high with area under the curve (AUC) values of 0.94 and 0.95 for the dry and wet seasons, respectively. Our results will be critical for identifying the available suitable habitat that should be conserved to safeguard this species from extinction. 相似文献
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Diets of the African Civet Civettictis civetta (Schreber, 1778) in selected coffee forest habitat,south‐western Ethiopia
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Tadesse Habtamu Afework Bekele Raya Ahmed Tsegaye Gadisa Belay Birlie Taye Tolemariam Berhanu Belay 《African Journal of Ecology》2017,55(4):573-579
Feeding ecology of the African civet, Civettictis civetta (Schreber, 1778), was studied in selected coffee forest habitat for two seasons between December 2012 and October 2013. The study was conducted in Limu Seka district, south‐west Ethiopia. Faecal analysis was employed to assess the diet spectrum, seasonal abundance and relative importance of food items. Over 55 different food items were identified from the analysis of 387 scat samples collected during the dry and wet seasons. In the coffee forest habitat, African civets showed omnivorous feeding habit with plant‐to‐animal diet biomass ratio of 1 : 1.36. A slight diet specialization was observed during the wet season (BA = 0.46) favouring animal prey. However, during the dry season, they showed generalist feeding habit (BA = 0.87) with more plant biomass in their diet. With over 64% occurrence and 14.4% biomass, coffee berries significantly contributed to the civets dry season plant diets. The excreted coffee beans, after civets ingested ripe coffee berries, are the tastiest product used by farmers for consumption and market. Seasonal collection of civet coffee from coffee forest floor economically supports the farmers while increasing the importance of civets in the habitat and hence contributing for its conservation. 相似文献
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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
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