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1.
The iconic Grey Crowned Crane Balearica regulorum is facing an increase in threats to its wetland habitat and poaching for the captive trade market. This has resulted in an enduring long-term decline in population numbers, which led to the species being listed as Endangered in the IUCN Red List. In Rwanda, Grey Crowned Cranes are threatened by human factors often driven by conditions of poverty, livelihood disadvantage and lack of conservation awareness. Previous population estimates suggested there were fewer than 500 Grey Crowned Cranes left in Rwanda. The Rwanda Wildlife Conservation Association and its partners have been working to eliminate the illegal trade and boost the population numbers in Rwanda. In August 2017, the first national census of Grey Crowned Cranes in Rwanda was carried out to serve as a baseline and to increase the accuracy of previous estimations. The survey was conducted over three days using both aerial and ground survey techniques. The results show that at least 487 Grey Crowned Cranes occur in Rwanda and include details on distribution and habitat type. Challenges for Grey Crowned Crane conservation at different sites are discussed, such as wetland transformation for agriculture, and illegal activities in protected marshlands. To ensure the long-term viability of this species, there is a need for upscaling of conservation efforts in key crane areas, continued monitoring of the crane population including trans-boundary collaboration, and strategies to promote the sustainable use of wetlands.  相似文献   

2.
《Ostrich》2013,84(1-2):90-94
The three South African crane species — the Blue Crane (Anthropoides paradisea), the Wattled Crane (Bugeranus carunculatus) and the Grey Crowned Crane (Balearica regulorum regulorum) — are listed as threatened by the IUCN. This study investigated the suitability of Randomly Amplified Polymorphic DNA markers in paternity testing in these species. RAPD primers were tested for polymorphism and RAPD profiles were scored and screened for sex linkage. The average Band Sharing Coefficient (BSC) of unrelated individuals was 0.665 (±0.103) for Blue Cranes, 0.745 (±0.060) for Grey Crowned Cranes and 0.736 (±0.056) for Wattled Cranes. Comparisons of these BSC values for unrelated individuals with BSC values of parent:offspring combination within the Blue Crane and the Grey Crowned Crane gave inconsistent results, with some parent:offspring BSC values being lower than the BSC of unrelated individuals. The results indicate that RAPDs are inappropriate for use in paternity testing in South African cranes. In the future, microsatellites should be investigated as an alternative paternity-testing technique to RAPD analysis.  相似文献   

3.
W. R. Siegfried 《Ostrich》2013,84(1-3):101-103
Siegfried, W. R. 1985. Relative abundance of cranes (Gruidae) in the Cape Province. Ostrich 56:101-103.

The results of monthly roadside counts of Crowned Cranes Balearica regulorum, Wattled Cranes Grus carunculatas and Blue Cranes Anthropoides paradisea show that Blue and Crowned cranes occurred most abundantly and densely in the eastern part of the Cape Province in 1965–1966. The Blue Crane's average relative abundance was approximately four times that of the Crowned Crane whose population occupied tend to breed in summer, the Blue Crane slightly earlier than the Crowned Crane. The population of the Wattled Crane was a small relict, occurrin in East Griqualand. Based on a rough estimate, there were about 1000–1500 Crowned Cranes and about 7000–10000 Blue Cranes in the Cape Province in the mid-1960s.  相似文献   

4.
William Olupot 《Ostrich》2016,87(3):263-270
The Grey Crowned Crane Balearica regulorum was uplisted to globally Endangered in 2012. There is urgent need to determine the threats they face at local levels for their conservation. I conducted formal point-count surveys around the wetlands of eastern Uganda and observed no cranes. Groups of cranes were encountered when following directions from local inhabitants. Results from a questionnaire survey suggested that cranes make use of most of the wetlands in the region, and that the birds occur in small flocks averaging 6–8 individuals. Wetland loss through farming was reported to be the main threat, but I also documented poisoning, roost disturbance, and the collection of eggs and chicks. Rigorous conservation and education programs are needed to ensure the long-term survival of cranes and storks in this region.  相似文献   

5.
《Ostrich》2013,84(3-4):186-194
There The Wattled Crane Bugeranus carunculatus is one of the top five most threatened bird species in South Africa, with the main threat being the loss of undisturbed breeding habitat. A basic understanding of this species' use of its environment is needed to implement conservation action. This quantitative study focused on determining the home range size of active breeding pairs in the KwaZulu-Natal midlands of South Africa, and assessing the land use composition of these home ranges. Wattled Cranes were found to have an average home range size of 16.64km2, consisting mostly of open natural grassland (mean of 75.5% of the overall home range of pairs). Other significant land use contributions to the home ranges were temporary irrigated and dryland cultivated agriculture. The core breeding area (wetland) of the home range constituted only 2.3% of the overall home range size, consisting of similar proportions of both wetland (48.9%) and grassland (51.8%) habitat. This indicates the dependence of Wattled Cranes on specific wetland habitats, surrounded by natural grassland. Wattled Cranes show home range sizes larger than other similar-sized crane species, suggesting that this may be as a result of their large body size and their occupation of highly transformed and fragmented habitats in an agricultural landscape. However, the occurrence of transformed land use types in home ranges suggests that breeding pairs tolerate some degree of disturbance within their home ranges. The home ranges do not appear to be currently restricted by surrounding land use types, indicating that factors other than habitat loss may be contributing to breeding site losses. The study has therefore indicated the need for closer working relationships between conservationists and agricultural communities to promote the conservation of valuable natural grasslands surrounding wetlands.  相似文献   

6.
中国鹤类现状及其保护对策   总被引:17,自引:2,他引:15  
中国有9种鹤类,其中灰鹤(Grus grus)、黑颈鹤(Grus nigricollis)、丹顶鹤(Grus japonensis)、白枕鹤(Grus vipio)、赤颈鹤(Grus antigone)、蓑羽鹤(Anthropoides virgo)在中国进行繁殖。中国政府为保护鹤类采取了大量有效措施。本文在结合当前鹤类数量和保护现状的基础上,对中国鹤类的保护对策进行探讨。  相似文献   

7.
Paul Mafabi 《Ostrich》2013,84(1-2):96-98
Mafabi, P. 2000. The role of wetland policies in the conservation of waterbirds: the case of Uganda. Ostrich 71 (1 & 2): 96–98.

Wetlands in Uganda provide important habitats for birds including several endemic species. With the ever increasing pressure to convert wetlands to agricultural lands, several species have lost their habitats, while others have become pests due to their opportunistic behaviour in modified habitats. The causes of wetland drainage and conversion in Uganda include population growth, economic reforms and a severe lack of information, legislation and inter-sectoral co-ordination. Community uses of wetlands have clear impacts on waterbirds. At Busolwe (case study 1) there is competition for land-use between Crowned Crane Balearica regulorum and man. Priority community uses of wetlands include fish-farming, agro-forestry and bee-keeping. There is a need for integrating bird conservation into overall wetland conservation objectives, especially with the aim of maintaining conditions suitable for waterbird survival during critical stages of the life-cycle. National wetland policies can play an important role in the conservation of waterbirds, as learned from Uganda's experiences. Recommendations for integrating bird conservation into the national wetland policy framework (as well as into national, district and local level planning processes) are made, which point to close co-operation between stakeholders for better management and on improved appreciation of wetlands values.  相似文献   

8.
就地保护中实施迁地保护是濒危物种保护的较为有效的形式。扎龙保护区自1976年筹建以来,就计划并开展了以人工辅助繁育丹顶鹤(Grus japonensis)种群为平台的孵化、训飞、放飞工作,本文通过常规的统计方法对扎龙保护区自建区以来的丹顶鹤孵化、训飞、放飞数据进行了分析。结果显示,建区至今,人工辅助繁育丹顶鹤种群的年均孵化成功率为77.41%(1981年最高,为100%);孵化成活量整体呈上升趋势,年均约为27只(2003年最高,为52只),近10年来基本维持在30~50只之间;训飞规模在逐年提高,近年来基本维持在100~120只之间;放飞规模与训飞规模同步也在逐年提高,年均放飞8只,2009年以来维持在10只以上;放飞野化的丹顶鹤已记录于中国的江苏盐城保护区、山东黄河三角洲保护区、韩国铁原地区。进一步分析表明,扎龙保护区在丹顶鹤保护方面已取得了一定的成绩。  相似文献   

9.
贵州草海湿地是世界上最大的黑颈鹤东部种群越冬地之一。黑颈鹤在草海越冬期极其依赖农耕地觅食存活,但当地人鸟争地冲突严重、觅食地萎缩加剧。为此,运用空间点格局分析及缓冲区叠加分析,探究黑颈鹤觅食地与农耕地空间关联性,并精确确定出重点保护管理区域,结果表明:1)研究期间,两年共在草海湿地周边农地确定黑颈鹤觅食点216处,其中家庭鹤觅食地99处、集群鹤觅食地117处,越冬种群中83%的个体依赖农耕区觅食;2)区域尺度上,家庭鹤与集群鹤的觅食点分布均为聚集分布,但集群鹤觅食点聚集程度较家庭鹤更高;觅食地与农耕地在空间聚类上呈正相关关系,并在3.2 km距离尺度下聚类程度最高;3)基于空间关联性,通过缓冲区叠加分析,共确定最适宜的农地觅食地53.74 km2,并划定2处重点核心保护区域及2处次重核心保护区域范围。研究结果对于揭示区域尺度上黑颈鹤觅食地与农耕地空间关系,指导保护管理者加强重点区域管理,以及对区域土地利用规划和缓解人鸟争地矛盾,具有重要的理论与实践意义。  相似文献   

10.
鄱阳湖围垦区藕塘越冬白鹤的时间分配与行为节律   总被引:1,自引:0,他引:1  
邵明勤  龚浩林  戴年华  植毅进  徐宁  卢萍 《生态学报》2018,38(14):5206-5212
2016年12月—2017年3月,采用瞬时扫描法研究了鄱阳湖围垦区藕塘生境中白鹤Grus leucogeranus越冬期的行为,共扫描2560次,23219只次,包括18031只次成鹤和5188只次幼鹤。结果表明,觅食(41.78%)、警戒(25.02%)、修整(15.00%)和休息(10.84%)是白鹤越冬期的主要行为。与自然生境相比,藕塘生境中白鹤主要采取多休息和修整的策略来节省能量支出。成鹤的觅食行为(35.29%)显著低于幼鹤(62.42%)(F_(1,12)=45.977,P0.01),警戒行为(28.66%)则显著高于幼鹤(10.26%)(F_(1,12)=38.975,P0.01)。家庭群成鹤觅食行为(43.96%)极显著高于非家庭群成鹤(27.04%)(F_(1,12)=60.169,P0.01)。家庭群成鹤需要喂食幼鹤,它们花费更多的时间觅食弥补能量的消耗。行为节律上,白鹤各时段觅食行为占总行为的比例均较高,11:00—11:59出现明显高峰,占总行为的48.64%。警戒行为无明显的低谷和高峰。成鹤在各时段的觅食行为比例均明显低于幼鹤,成鹤和幼鹤的觅食曲线变化趋势相似,即觅食比例的升高和降低比较同步。成鹤在各时段的警戒行为和修整行为比例均明显高于幼鹤,成幼鹤的休息行为比例在各时段差别不大,均在14:00—14:59有个明显的高峰。家庭群成鹤的觅食行为比例几乎在各时段均明显高于非家庭群,家庭群成鹤的修整行为和休息行为在大部分时段均低于非家庭群成鹤。因此家庭群成鹤采取多取食,少休息和修整的策略提高自身的适合度,同时保证对后代的抚育。  相似文献   

11.
对鸟类巢期的研究不仅可以丰富鸟类繁殖生物学资料,也可为理解和研究鸟类的生态适应与进化提供重要线索和依据。2013—2014年3月份至7月份,在若尔盖湿地保护区及周边对55对繁殖黑颈鹤的营巢时长进行了研究,调查结果显示:黑颈鹤的营巢时长在0.5—40 d之间,平均巢期为(6.7±9.3)d;在其营造的4种巢型中,巢期长短依次为:泥堆巢草堆巢草墩巢岛地巢,且差异性极显著(P0.001),巢期与巢型显著相关(r=0.728);在其营巢的3种巢址生境中,巢期长短依次为:湖泊生境沼泽生境河流生境,且差异性极显著(P0.001),巢期与巢址生境显著相关(r=0.315);从不同营巢月份看,巢期长短依次为:4月份巢5月份巢6月份巢,且差异性极显著(P0.01),巢期与筑巢月份显著相关(r=0.664);巢期与巢体积大小具有显著相关性(r=0.856),即营巢时间越长巢体积越大。黑颈鹤的营巢时间长短主要受营巢生境、月份和做巢类型的影响。  相似文献   

12.
Nathan Gichuki 《Ostrich》2013,84(1-2):74-79
Gichuki, N. 2000. Influence of breeding on foraging behaviour and diet of crowned cranes. Ostrich 71 (1 & 2): 74–79.

This study investigated the effects of breeding on the foraging behaviour and diet of Grey Crowned Cranes Balearica regulorum in the Kitale area, western Kenya. During the study period (July 1994 to June 1996), 86 pairs successfully bred in 290 ha of wetlands. Egg-laying extended from July to November, indicating that the timing of nesting was flexible. Breeding and non-breeding adult cranes as well as immature birds foraged in grasslands, crop stubble, sown fields and wetlands. These habitats were not used according to the available proportions. Breeding commitments restricted parental adults to habitats within their territories while non-parental adults and sub-adults exploited a wider range of habitats. Further, breeding adults and juveniles had smaller foraging range sizes than those of non- breeding adults and sub-adults. Reduced foraging ranges by breeding birds appear to be a trade-off between energy expenditure in self-maintenance and reproduction. The diet of breeding and non-breeding adults was generally similar consisting of graminoid seeds and arthropods. Breeding birds, however, increased consumption of protein rich animal food and non-seed plant material. Selectivity of food items was greatest among breeding adults. Overall, breeding commitments resulted in reduced foraging range and variety of food items available but the major components of the diet remained the same for all adults and immature birds.  相似文献   

13.
Agbelusi, E.A. & Afolayan, T.A. 2000. Distribution of waterfowl in the wetland of Northern Nigeria. Ostrich 71 (1 & 2): 73.

Nigeria with a land area of 923 850 km2 has approximately 24 000 km2 of wetland. These wetlands are scattered all over the country and include the man-made lakes. The wetlands of northern Nigeria are important breeding sites for Afrotropical duck and also serve as the winter refuge for Palearctic birds from Europe. About 13 sites have been identified as the actual habitat and concentration points for waterfowl in the wetlands of northern Nigeria. Among these areas, the Hadeija-Nguru wetland represents one of the most productive and ecologically significant wetlands in Nigeria. This area supports about 58 000 waterbirds, belonging to about 376 species, which consist mostly of Palearctic and Afrotropical migratory birds. Some of the important bird species that are associated with the wetland of northern Nigeria are Black Crowned Crane, Pintail, White Pelican, White-faced Tree Duck, Knob-billed Goose, Spur-winged Goose, Gull-billed Tern and Saddle-billed Stork. The paper also discusses the management implications for waterfowl conservation and tourism in Nigeria.  相似文献   

14.
Habitat loss is one of the key factors underlying the decline of many waterbird species, including Siberian Crane (Grus leucogeranus), a threatened species worldwide. Wetlands are the primary stopover for many waterbirds and restoration of these wetlands involves both hydrological restoration and water resource management. To protect the stopover sites of Siberian Cranes, we collected Siberian Crane stopover numbers, meteorological and hydrological data, and remote sensing data from 2008 to 2011 in Momoge National Nature Reserve, one of the largest wetlands in northeastern China. A model was developed to estimate the suitability of Siberian Crane stopover sites. According to our results, the most suitable daily water level for Siberian Cranes between 2008 and 2012 occurred in the spring of 2008 and in the Scirpus planiculmis growing season and autumn of 2010. We suggest a season-dependent water management strategy in order to provide suitable conditions at Siberian Crane stopover sites.  相似文献   

15.
The spring mound deposit Florisbad (Free State, South Africa) yielded several bird remains dating to the late Middle Pleistocene. These specimens derive from spring vent structures and are the product of natural taphonomic processes relating to the spring as primary sampling agent. The bird fossils can be assigned to Ostrich, Struthio camelus; Greater Flamingo, Phoenicopterus ruber roseus; Wattled Crane, Bugeranus carunculatus; an anatine dabbling duck; and a francolin with strong resemblance to Shelley’s Francolin, Scleroptila shelleyi. As in the case of the large mammal record, the bird remains from the Florisbad spring reflect two components in the palaeoenvironment. Evidence for Greater Flamingo, Wattled Crane, and a dabbling duck strongly supports previous hypotheses regarding the presence of a palaeolake system, while records for Ostrich and a francolin, but also Wattled Crane accord with the presence of open landscapes, such as grasslands.  相似文献   

16.
ABSTRACT.   Because their breeding and wintering areas are in remote locations, little is known about the biology of Black-necked Cranes ( Grus nigricollis ), including their migratory behavior. Using satellite telemetry, we monitored the migration of Black-necked Cranes ( N = 6) in China to determine migration routes and the location of stopover sites. From 2005 to 2007, four cranes were tracked during two spring migrations and one fall migration, one was tracked during one spring and one fall migration, and one was tracked during one spring migration. On average, the cranes made seven flights over a 5-d period to migrate 651 km to breeding areas in the spring. In the fall, birds averaged six flights in 5 d to migrate 694 km. The routes traveled by cranes during spring and autumn migration were similar. Both the migration distances and duration of migration are the shortest reported for any crane species to date. Most stopover sites were in areas along rivers and close to wetlands in the Daliang Mountains and the Ruoergai Plateau. Conservation measures are needed to reduce habitat loss (wetland and pasture) in the Daliang Mountains and establish a reserve for stopover sites in the Ruoergai marshes, such as Longriba and Bai River in Hongyuan County.  相似文献   

17.
鄱阳湖是世界重要的候鸟越冬地,承载了全球约98%的白鹤(Leucogeranus leucogeranus)。然而,近年来鄱阳湖沉水植被退化严重,白鹤的传统食物苦草(Vallisneria spp.)冬芽丰富度急剧减少。食物短缺导致白鹤的觅食生境由自然湿地的浅水生境转移至稻田、藕塘等人工生境,稻田在白鹤保护中发挥的作用日益突出。了解鄱阳湖周边稻田对白鹤的承载力可为白鹤的保护和管理提供科学依据。为此,调查了鄱阳湖周边稻田散落稻谷的生物量,测量了稻谷的营养成分,并利用遥感影像对鄱阳湖周边10 km范围内稻田的总面积进行估算,从而得出鄱阳湖周边稻田散落稻谷能提供的总能量。然后,计算稻田中以稻谷为主要食物的6种鸟类的日能量消耗,用以表示日能量摄入。最后,依据稻田能提供的总能量、鸟类的日能量摄入、鸟类的越冬时长、以及各种鸟类的数量占比,计算得出鄱阳湖周边稻田能承载的白鹤数量。结果表明,鄱阳湖周边稻田散落稻谷的生物量为6.494 g/m2,环鄱阳湖周边10 km范围内稻田的总面积为1984.46 km2,这些稻田能承载的鸟类总数量为140860只,其中能承载的白鹤数量为10775只,超过了全球白鹤的总数量(3500-4000只)。因此,鄱阳湖周边稻田能为白鹤等鸟类提供丰富的食物资源。  相似文献   

18.
East African and south African churchills (Petrocephalus, Mormyridae) were synonymised in 1959 to become members of a single species of subcontinental, southern African distribution, Petrocephalus catostoma (Günther, 1866). By comparison with the type material for P. catostoma from the Ruvuma River and P. stuhlmanni from the Ruvu River, both of East African origin, we confirm the South African form of churchill to represent a new species, P. wesselsi, ranging from the northern Limpopo and Incomati systems south to the Pongola River (Natal) as its southern limit. We also compared churchills from the Sabie River (25° S, South Africa, Incomati system) with churchills from the Upper Zambezi River (17° S, Namibia), using electric organ discharges (EODs) and morphology. The duration of an EOD pulse of the South African form (N = 39; 943.2±S.E. 18.82µs) is, on average, more than twice that of the Upper Zambezi form (N = 37; 436.6±15.1µs), and the amplitude of the second head-positive phase (P2 phase relative to P1 = 1) significantly weaker (0.133 ± 0.0005 vs. 0.472 ± 0.002 for Upper Zambezi males, 0.363 ± 0.03 for Upper Zambezi females). In contrast to the Upper Zambezi form, the EOD of the South African form exhibits no difference between the sexes. Fish from the two origins differ significantly in 11 out of 14 anatomical characters studied, confirming molecular genetic differentiation on the species level.  相似文献   

19.
Species primarily dependent on habitats outside protected areas have to cope with the direct pressure of human utilization or harassment, and the indirect pressure of habitat modification. In Uganda, wetlands mainly used by cranes occur mostly outside protected areas. The country's wetlands are however under heavy modification, and this and other pressures are thought to have reduced crane populations to 10–30% of the number in the early 1970s. From January 2005 to January 2006, we assessed the status of crane breeding and distribution in the country. Breeding and foraging sites were assessed through a nationwide newspaper survey, and visits to wetlands. We established occurrence of 21 nests during the study period, and crane use of 27 out of 30 districts surveyed. Crane harassment and trapping were common during breeding, as was crop damage by cranes. This is the first attempt to show the distribution of crane breeding outside protected areas throughout the country. In addition to maintaining suitable breeding habitat, survival of cranes in Uganda lies in part in community engagement and punishing crimes related to hunting and destruction of nests.  相似文献   

20.
白鹤(Leucogeranus Leucogeranus)是国家Ⅰ级重点保护野生动物,唯一一种极度濒危(CR)鹤类,分布和种群数量是评估其濒危程度的重要参数。无人机调查作为目前生态学研究的一个重要调查方法,为查明白鹤的越冬分布、种群数量及幼鸟比例,于2022年1月使用地面监测结合无人机调查的方法在江西、山东、安徽、湖南、湖北等地的湖泊和农田中开展越冬白鹤调查。野外调查共记录白鹤5607只,网络信息检索在调查区域外的8个地点记录白鹤9只,合计记录越冬白鹤5616只。其中江西鄱阳湖记录到越冬白鹤4813只,占总数的85.7%,主要分布在康山垦殖场、五星垦殖场和成新垦殖场;山东黄河三角洲记录到越冬白鹤625只,占总数的11.1%。安徽、湖南、湖北分别记录到越冬白鹤34,63和72只。对部分群体的白鹤幼鸟数量进行统计,4680只白鹤中,记录到幼鸟674只,幼鸟比例为14.4%,其中湖南越冬白鹤幼鸟比例最高,达28.6%,山东越冬白鹤幼鸟比例最低,为11.5%。调查刷新了白鹤种群数量,证实了山东黄河三角洲是目前除江西鄱阳湖外最重要的白鹤越冬地,缓解了白鹤越冬期过度集中的压力。基于本研究结果,我们...  相似文献   

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