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1999-2003年,在捷克共和国特布盆地生物圈保护区(Tebo Basin Biosphere Reserve)内,我们对13个采矿后形成的人工湖中水鸟群落的形成过程进行了研究.我们假定生活在邻近鱼塘中的水鸟会逐渐向这些人工湖迁移和聚集.在这些人工湖中共记录到42种水鸟,隶属于10个目,其中17种典型的海滨鸟类是该群落的重要组成部分.这些水鸟的季节动态过程与各物种自身的生活史阶段有关(如筑巢、迁徙),同时也被人类的采矿活动所影响.环境因素和人类干扰影响了绿头鸭(Anas platyrhynchos)、疣鼻天鹅(Cygnus olor)和凤头鸊鷉(Podiceps cristatus) 等优势种的分布.沙坑湖作为一种独特的生境为本保护区的濒危物种提供了栖息地,如:小苇(开鸟)(Ixobrychus minutus)、大苇莺(Acrocephalus arundinaceus)及其它潜在分布的鸟类.对南波西米亚地区沙坑湖鸟类的研究,可为其它相似地区水鸟群落演替研究提供了重要经验 相似文献
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Waterbirds are often observed to move between different wintering sites within the same winter—for example, in response to
food availability or weather conditions. Within-winter movements may contribute to the spreading of diseases, such as avian
influenza, outside the actual migration period. The Common Pochard Aythya ferina seems to be particularly sensitive to infection with the highly pathogenic avian influenza virus H5N1 and, consequently,
could play an important role as vectors for the disease. We describe here the within-winter movements of Pochards in Europe
in relation to topography, climate, sex and age. We analysed data provided by the Euring data bank on 201 individuals for which records from different locations from the same winter (December–February) were available.
The distances and directions moved within the winter varied markedly between regions, which could be ascribed to the differing
topography (coast lines, Alps). We found no significant differences in terms of distances and directions moved between the
sexes and only weak indications of differences between the age classes. In Switzerland, juveniles moved in more westerly directions
than adults. During relatively mild winters, winter harshness had no effect on the distances travelled, but in cold winters,
a positive relationship was observed, a pattern possibly triggered by the freezing of lakes. Winter harshness did not influence
the directions of the movement. About 41% (83/201) of the Pochards that were recovered at least 1 km from the ringing site
had moved more than 200 km. A substantial number of birds moved between central/southern Europe and the north-western coast
of mainland Europe, and between the north-western coast of mainland Europe and Great Britain, whereas no direct exchange between
Great Britain and central/southern Europe was observed. Within-winter movements of Pochards seem to be a common phenomenon
in all years and possibly occur as a response to the depletion of food resources. This high tendency to move could potentially
contribute to the spread of bird-transmitted diseases outside the actual migration period. 相似文献
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崇明东滩冬季水鸟的种类和生境偏好 总被引:32,自引:2,他引:30
20 0 2年 11月~ 2 0 0 3年 1月对崇明东滩自然保护区的越冬水鸟在 5种生境类型的分布、数量分别做了 2 0 0 0m× 10 0m的样带调查。共观察到水鸟 4 9种 ,整个群落个体总数 345 0 4只。其中低潮盐藻光滩带有鸟类37种 ,占水鸟个体总数的 39% ;海三棱草外带有 19种 ,占 6 % ;海三棱草内带有 10种 ,占 5 % ;堤外芦苇带有 4种 ,占 3% ;堤内鱼塘 -芦苇区有 37种 ,占 4 7%。这一结果证实了把围垦地转变为鱼塘 -芦苇湿地的生态恢复行动的合理性 ,因为最大的越冬水鸟物种多样性和个体多度出现在这种湿地中。 相似文献
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José A. Masero 《Biodiversity and Conservation》2003,12(6):1157-1173
Because many natural waterbird habitats are threatened by human disturbance and sea level rise, it is vitally important to identify alternative wetlands that may supplement declining natural habitats. Coastal salinas are anthropogenic habitats used for obtaining salt by evaporation of sea water. These habitats support important numbers of waterbirds around the world, but their importance as feeding habitats is poorly understood. I evaluated salinas as feeding habitats relative to natural intertidal habitats by comparing time spent foraging, prey-size selection, and net energy intake rate of four overwintering small-sized shorebird species on intertidal mudflats and on adjacent salinas. In winter, Dunlin Calidris alpina, Curlew Sandpiper C. ferruginea and Sanderling C. alba predominantly used the mudflats, whereas Little Stint C. minuta fed mainly on the salina. In the pre-migration fattening period, all species preferred to feed on the salina, significantly increasing the time they spent feeding in the supratidal pans. Net energy intake rates (kJ min–1) were significantly higher on the salina than on the intertidal mudflats in 60% of all comparisons. On average, salina contributed 25.2 ± 24.2% (range: 4–54%) of the daily consumption in winter and 78.7 ± 16.4% (range: 63–100%) of the daily consumption in the pre-migration period. I recommend that modern active salinas maintain flooding conditions in the evaporation pans throughout winter, thus increasing the available surface for foraging waterbirds. I conclude that the conservation of salinas at coastal wetlands is a viable approach for shorebird conservation. 相似文献
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2008年4—6月对青海湖湖区主要水鸟的稳定性碳和氮同位素组成进行了测定,依据营养级间的同位素富集效应以及营养级计算模型(TL水鸟=3+ (δ15N水鸟-1.78-δ15N浮游动物)/3.8),分析并确定了主要水鸟在生态系统中的营养级层次。相对于水生动物而言,水鸟的δ15N具有明显的富集效应,而δ13C不显著。依据稳定性同位素的营养富集效应模型,通过普通鸬鹚(Phalacrocorax carbo)和青海湖裸鲤(Gymnocypris przewalskii)间δ15N的比对,确定了该系统中排泄尿酸的水鸟稳定性氮同位素的富集因子为1.78‰。利用δ15N建立了稳定同位素比值与营养层次的关系。浮游植物、浮游动物、青海钩虾(Gammarus suifunensis)、裸鲤和水鸟的营养层次分别为1.64—2.06、2.35—2.83、2.63、3.64—4.20和3.35—4.93。由于湖区普通鸬鹚、渔鸥(Larus ichthyaetus)、棕头鸥(Larus brunnicephalus)和凤头(Podiceps cristatus)的食物来源主要是湖体中的裸鲤,由模型计算得到它们处在最高的营养级阶层;赤麻鸭(Tadorna ferruginea)、普通燕鸥(Sterna hirundo)和红脚鹬(Tringa totanus)属杂食性水鸟,营养阶层居中;而斑头雁(Anser indicus)由于主要以水生和陆生植物为食,处在最低的营养阶层。裸鲤资源未来的状况必将影响到普通鸬鹚、渔鸥、棕头鸥,以及凤头的生长、繁衍以及整个系统的群落结构和稳定性。 相似文献
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Mariano Paracuellos 《Biodiversity and Conservation》2006,15(14):4569-4582
The factors regulating the distribution of dabbling and diving waterbirds were studied, taking into account habitat selection
by the species in a wetland complex of 26 ponds in south-eastern Spain. Such information can be used to management and conservation
of wetland threatened bird species. Direct counts and feeding-microhabitat surveys of waterbirds were conducted. The feeding-niche
width and the feeding-microhabitat use, as a function of the horizontal spatial gradient in the ponds, were related to the
mean size of ponds used for each species. While the more generalist birds, which usually feed close to the shore, probably
had available resources in small ponds, specialists that also frequently selected central zones of the pond had proportionally
more limited feeding space and, therefore, less resource availability in small ponds. The differences in habitat selection
of the different species appeared to encourage their hierarchical disappearance from the wetland complex at the same rate
as the ponds diminished in size (‘nested’ pattern). The results support the conservation, restoration or creation of, at least,
ponds of greater size in order to preserve extensive open-water zones in the wetlands and maintain the greatest number of
specialist, threatened, and area-dependent species, such as the globally endangered White-headed Duck (Oxyura leucocephala). 相似文献
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黑龙江兴凯湖位于中俄交界,该地区水鸟的迁徙路线及其保护状况受到我国及相邻国家政府和保护组织的高度关注。我们整理了兴凯湖水鸟的环志回收数据,对水鸟的迁徙规律进行了分析。结果表明,从2010年至2019年兴凯湖共环志鹤鹳类和雁鸭类968只,回收记录共29只次,其中白枕鹤(Grus vipio)6只次、东方白鹳(Ciconia boyciana)8只次、斑嘴鸭(Anas poecilorhyncha)3只次、绿头鸭(A. platyrhynchos)3只次、琵嘴鸭(A. clypeata)7只次、凤头潜鸭(Aythya fuligula)1只次和豆雁(Anser fabalis)1只次。水鸟环志回收数据揭示了兴凯湖鹤鹳类和雁鸭类的主要迁徙规律,证实了兴凯湖作为东北亚水鸟迁徙廊道的重要性,为我国与相邻国家开展水鸟的联合保护提供科学依据。 相似文献
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Landscape genetics identifies streams and drainage infrastructure as dispersal corridors for an endangered wetland bird 下载免费PDF全文
Charles B. van Rees J. Michael Reed Robert E. Wilson Jared G. Underwood Sarah A. Sonsthagen 《Ecology and evolution》2018,8(16):8328-8343
Anthropogenic alterations to landscape structure and composition can have significant impacts on biodiversity, potentially leading to species extinctions. Population‐level impacts of landscape change are mediated by animal behaviors, in particular dispersal behavior. Little is known about the dispersal habits of rails (Rallidae) due to their cryptic behavior and tendency to occupy densely vegetated habitats. The effects of landscape structure on the movement behavior of waterbirds in general are poorly studied due to their reputation for having high dispersal abilities. We used a landscape genetic approach to test hypotheses of landscape effects on dispersal behavior of the Hawaiian gallinule (Gallinula galeata sandvicensis), an endangered subspecies endemic to the Hawaiian Islands. We created a suite of alternative resistance surfaces representing biologically plausible a priori hypotheses of how gallinules might navigate the landscape matrix and ranked these surfaces by their ability to explain observed patterns in genetic distance among 12 populations on the island of O`ahu. We modeled effective distance among wetland locations on all surfaces using both cumulative least‐cost‐path and resistance‐distance approaches and evaluated relative model performance using Mantel tests, a causal modeling approach, and the mixed‐model maximum‐likelihood population‐effects framework. Across all genetic markers, simulation methods, and model comparison metrics, surfaces that treated linear water features like streams, ditches, and canals as corridors for gallinule movement outperformed all other models. This is the first landscape genetic study on the movement behavior of any waterbird species to our knowledge. Our results indicate that lotic water features, including drainage infrastructure previously thought to be of minimal habitat value, contribute to habitat connectivity in this listed subspecies. 相似文献