共查询到18条相似文献，搜索用时 156 毫秒
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2011年4月,在七星河保护区内用生境因子测定法、样方法对苍鹭的巢选择进行了初步研究。结果表明:(1)七星河保护区苍鹭巢为地面型,均营巢于芦苇沼泽,窝卵数以4～5枚卵居多(84.21%);(2)巢外径为95.31±1.30 cm,巢内径为40.29±0.54 cm,巢高为57.51±1.91 cm,巢深为11.51±0.35 cm;(3)巢周水深为42.18±1.94 cm,距道路距离为446.58±13.9 m,巢周芦苇高度为323.12±3.87 cm,密度为263.17±4.20根/m~2,直径为8.11±0.41 mm,盖度为1.32±0.07%。进一步比较分析发现:栖息型、水位、芦苇处理方式的不同,苍鹭巢特征和巢周环境也不同。 相似文献
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野生动物种群格局分析方法 总被引：1，自引：0，他引：1
本文综述了几种种群格局分析方法，以苍鹭营巢的分布格局为例，探讨了这些方法在野生动物种群生态学上的应用，为研究野生动物种群的数量动态及其行为规律提供了理论基础。 相似文献
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为了研究江苏大丰麋鹿国家级自然保护区互花米草生境中繁殖鸟巢的被捕食情况及影响捕食的因素,2014年3~6月,在保护区第三核心区鸟类繁殖生境中,使用人工巢及真实鹌鹑蛋进行巢捕食实验的方法进行巢捕食实验,分析不同巢高度、覆盖度、边缘距离、植被密度等因素对鸟巢被捕食的影响。实验共放置520个人工巢,1 040枚卵,使用红外相机对部分人工巢进行监测。结果表明:在江苏大丰麋鹿自然保护区互花米草生境内,人工巢存在较高的被捕食率,共有352巢被捕食,占67.7%,对11个变量进行逻辑斯蒂回归,巢高度、植被均高、主要植被密度、距边缘距离、水平覆盖度、上层垂直覆盖度等6个变量进人最终模型,巢高度、距边缘距离与巢被捕食显著相关。通过红外相机拍摄从102个监测巢中记录到69个捕食事件,68巢黑线姬鼠(Apodemus agrarius)和1巢黑眉锦蛇(Elaphe taeniura)捕食。我们认为互花米草生境中缺乏啮齿类动物的天敌是当地人工巢被捕食的主要原因。 相似文献
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黑龙江安邦河自然保护区黑翅长脚鹬繁殖生境初步研究 总被引：3，自引：0，他引：3
2009年5～6月,在安邦河自然保护区对黑翅长脚鹬的繁殖期生境选择进行了初步研究。利用样方法、因子测定法对黑翅长脚鹬的繁殖生境的植被（种类、高度、密度、盖度）、水深（巢区、距巢5 m、距巢30 m）、巢间距离、人为干扰距离等进行了测量,得到黑翅长脚鹬繁殖生境数据。并对数据做了方差分析和平均值比较等处理,结果显示黑翅长脚鹬偏爱在近岸浅水中营巢,对水深有严格的要求,巢周围平均水深在7.8 cm。巢区1 m×1 m样方内植被平均高度68.72 cm,密度为7.3棵/m~2,巢间平均距离76.49 m,平均人为干扰距离632.5 m。 相似文献
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2006年5月,对贵州中部的鹭鸟群巢进行了调查,共记录到11个繁殖群、1587巢,种类包括小白鹭(Egretta garzetta)、牛背鹭(Bubulcus ibis)、池鹭(Ardeola bacchus)、夜鹭(Nycticorax nycticorax)和苍鹭(Ardea cinema).最大的繁殖群在黄平风云崖和赤水宴府.种类以小白鹭为优势种,其巢数量占总巢数的49.7%;而苍鹭最少,仪占0.1%.所有鹭鸟巢均只发现于贵州中、北部,而南部的雷公山地区没有调查到.鹭鸟群巢在贵州中部的分布明显受到农田种植模式(冬天种植小麦和油菜,夏天种植水稻)的影响,繁殖巢主要分布于稻作区.但在贵州南部的主要稻作区却没有发现鹭鸟繁殖群巢,其原因尚待调查.对贵州黄平和赤水这两个较大鹭鸟群巢所在地需重点加以保护. 相似文献
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《经济动物学报》2021,(3)
为加强对海南捕鸟蛛(Cyriopagopus hainanus)的保育利用,在海南省三亚育才镇、乐东尖峰岭、五指山市三地,采用踏查和详查相结合的方式对海南捕鸟蛛巢穴生境特性及不同生境条件下巢穴密度与几何特征等筑巢生态学特征进行了研究。结果表明:海南捕鸟蛛适宜活动温度为24.0～27.3℃,巢周相对湿度为88%左右,多筑巢于西坡、南坡和西南坡的坡面与坎面上。其成体蛛巢密度的排序为次生林橡胶林槟榔林。成体蛛巢穴洞口直径和洞穴容积在三亚育才镇不同植被类型下差异显著(P0.05),其中,橡胶林次生林槟榔林;当植被类型为次生林时,成体蛛巢洞口直径和洞穴容积在三亚育才镇显著大于其他调查地(P0.05);当植被类型为橡胶林时,成体蛛巢洞穴容积在五指山市显著小于三亚育才镇(P0.05)。幼体蛛巢仅五指山市不同植被类型下的洞深值具有显著差异,表现为槟榔林下显著大于次生林下(P0.05),橡胶林下洞深值介于二者之间,与二者均无显著差异。说明生境可能影响海南捕鸟蛛巢穴的分布、密度与几何特征。 相似文献
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鹭岛位于黑龙江省海林县三道河子公社边安大队西一里之遥的牡丹江中。岛呈半月形,南北长约五百米,东西宽约一百米。岛上灌木丛生,蒿草过膝。全岛有三十七棵高二、三十米的老榆树,其中二十棵树上筑有鸟巢,最多的一棵树上筑有十七个巢。全岛共有一百六十五个巢,有千只苍鹭在树上栖息。这些苍鹭毫不惧人,昂首挺立排列枝头,时而发出“krok、krok”的低沉叫声。 相似文献
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John P. Severson Christian A. Hagen Jeremy D. Maestas David E. Naugle J. Todd Forbes Kerry P. Reese 《Strength and Conditioning Journal》2017,70(1):50-58
Conifer woodlands expanding into sage-steppe (Artemisia spp.) are a threat to sagebrush obligate species including the imperiled greater sage-grouse (Centrocercus urophasianus). Conifer removal is accelerating rapidly despite a lack of empirical evidence to assess outcomes to grouse. Using a before-after-control-impact design, we evaluated short-term effects of conifer removal on nesting habitat use by monitoring 262 sage-grouse nests in the northern Great Basin during 2010–2014. Tree removal made available for nesting an additional 28% of the treatment landscape by expanding habitat an estimated 9603 ha (3201 ha [± 480 SE] annually). Relative probability of nesting in newly restored sites increased by 22% annually, and females were 43% more likely to nest within 1000 m of treatments. From 2011 (pretreatment) to 2014 (3 yr after treatments began), 29% of the marked population (9.5% [± 1.2 SE] annually) had shifted its nesting activities into mountain big sagebrush habitats that were cleared of encroaching conifer. Grouping treatments likely contributed to beneficial outcomes for grouse as individual removal projects averaged just 87 ha in size but cumulatively covered a fifth of the study area. Collaboratively identifying future priority watersheds and implementing treatments across public and private ownerships is vital to effectively restore the sage-steppe ecosystem for nesting sage-grouse. 相似文献
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黑冠(开鳥)(Gorsachius melanolophus)分布于南亚、东南亚及东亚的热带和亚热带地区.由于此鸟种常繁殖于密林中,对其生态学特征知之甚少,目前仅有少量关于其食性的信息.我们通过分析日本南部八重山群岛黑冠(开鳥)食丸和胃的内含物,定量分析了该地区黑冠(开鳥)的食性特征.结果表明,黑冠(开鳥)最喜捕食陆地... 相似文献
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Saâd HANANE 《Integrative zoology》2014,9(3):349-359
The woodpigeon (Columba palumbus) is a common and widespread bird in Morocco (North Africa). I examined, over 2 years (2010 and 2011), the breeding density and nest placement of this game species in relation to nest site habitat and degree of human disturbance. The study area was in the Middle Atlas Tighboula mountain forest, Morocco, in a disturbed and an undisturbed site. Using data collected in the 2 study sites, I aimed to identify the factors influencing the placement of nests within holm oak trees (Quercus rotundifolia) and their densities. I found that habitat structures, influenced by grazing disturbance, have affected nesting density and the location of nests of this species. Woodpigeons place their nests in a higher position (3.42 ± 0.19 m) when disturbance intensity is high and lower (1.68 ± 0.1 m) when disturbance intensity is low, and show higher nesting density in less disturbed zone (3.1 ± 0.4 nests/ha) than in highly disturbed zones (1.4 ± 0.2 nests/ha). Grazing disturbance could pose a threat to population persistence at a broader scale and could potentially reduce the abundance of this species by altering the composition and the structure of the forest nesting habitat. Further multi‐scale studies are needed to assess the effects of different levels of grazing disturbance on woodpigeon nest density and placement, and to enhance our knowledge of the breeding behavior of this game species under variable environments. 相似文献
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Dead and sick grey heron chicks with multiple fractures of the leg and wing bones and/or bone deformities have been reported at Besthorpe Nature Reserve heronry in north Nottinghamshire since 1996. Forty-five grey heron carcases were examined, 35 from the Besthorpe colony and 10 from other colonies where bone disease was not known to occur. On the basis of the results of radiological studies, postmortem examinations, peripheral quantitative computed tomography scanning and four-point bending tests, it was concluded that the skeletal abnormalities were probably due to metabolic bone disease. 相似文献
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The behaviour of polyandrous and monogamous pale chanting goshawks Melierax canorus was investigated to determine if co-breeders, by defending the territory and nest contents, helped to increase the fitness of polyandrous trios. Polyandrous trios consisted of a female and male breeder, as well as a subordinate co-breeding male. Pale chanting goshawk males performed most of the interspecific territorial maintenance duties, as well as participating in aggressive intraspecific interactions against other mates on territory borders. Intraspecific territorial interactions were almost exclusively recorded in high-quality habitat, Karroid Broken Veld, and probably functioned in the defence of foraging habitat and potential mates, In this habitat, males of polyandrous families largely occupied exclusive sections of a territory. It is suggested that the cost of defending territories in Karroid Broken Veld was offset by the co-breeder’s contribution to high-risk, intraspecific territorial defence. During the nestling period females of polyandrous trios stayed at nesting sites for longer periods than did monogamous females and all males, enabling these females to guard the nest and act as sentinels. Predation of nestlings was recorded at the nests of monogamous pairs, but not at those of polyandrous trios. Co-breeders did not guard the nesting site but contributed directly to nest defence by either coming to the female‘s aid when solicited, or attacking potential predators when present at the nesting site. Co-breeders may also have helped indirectly, through activities such as provisioning prey to females that relieved them of their hunting duties. We suggest that the female’s nest guarding and the resulting lower nest predation may hold reproductive and fitness benefits for polyandrous breeders. 相似文献
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《Strength and Conditioning Journal》2020,73(1):128-137
Many grassland species coevolved with large herbivores and require habitats along the entire structural gradient created by grazing. Widespread declines of grassland birds, however, have prompted concerns about rangeland management. Conceptually, rest-rotation grazing functions as a conservation strategy to mimic historic disturbance regimes and create pasture-level heterogeneity in the absence of fire, but its utility for improving wildlife habitat has not been directly tested, particularly in the mesic mixed-grass prairie. We evaluated rest-rotation grazing as a conservation management technique compared with more traditional grazing systems, including summer rotation and season-long grazing, and assessed effects of different grazing systems and stocking rates on nest site selection and nest survival of sharp-tailed grouse (Tympanuchus phasianellus), an indicator species for grassland ecosystems. Both nest site selection and nest survival were directly related to vertical nesting cover, which was only weakly related to grazing management variables, including grazing system and stocking rate, at moderate stocking rates (≤ 2 animal unit month [AUM] ha− 1). Cattle presence during the nesting period had a positive effect on daily nest survival, potentially through an effect by either the cows or rancher presence on predator behavior. Overall, our results suggest that rest-rotation grazing did not contribute to pasture-level vegetation heterogeneity and that both the selective foraging of cattle and inherent topographic and edaphic variability in our study area may be stronger drivers of heterogeneity at the small spatial scale required by female grouse. 相似文献