东大山自然保护区喜马拉雅雪鸡(Tetraogallus himalayensis)的巢址选择

2004和2005年的4～7月,采用样方法和直接观察法,对甘肃省东大山自然保护区喜马拉雅雪鸡(Tetraogallus himalayensis)的巢址选择进行了研究.共测量36个巢址.研究表明,喜马拉雅雪鸡的巢主要分布于2601～3000 m之间,多在高山岩石草地和裸露岩石区、突出大石下和灌木下或草丛中、中坡及中坡以上的坡位、坡度26°～40°之间的阳坡和半阳坡上营巢.主成分分析表明,影响巢址选择的主要因子可分为捕食因子和食物因子两类,其主要因子依次为灌丛高度、距悬崖的距离、草本盖度、灌丛密度和物种丰富度;作为捕食因子与食物因子权衡的结果,其巢址选择有利于喜马拉雅雪鸡的野外生存.此外,悬崖环境(距悬崖的距离和500m内的悬崖数)在巢址选择中起到重要作用,这可能与雪鸡的避敌方式及飞翔能力较差有关.     

云南纳帕海自然保护区灰背伯劳的巢址选择

2013年5—6月,在云南省纳帕海自然保护区对灰背伯劳Lanius tephronotus的巢址选择进行了研究。结果显示,灰背伯劳对树种具有极强的偏好性,有78.48%(n=62)的巢位于火棘Pyracantha sp.灌丛中,枝条具刺是影响灰背伯劳选择筑巢树的首要因素。主成分分析表明,影响灰背伯劳巢址选择的因素有5类:距离因子(巢距道路距离、距居民点距离)、安全性因子(刺数量、刺长度)、觅食生境因子(耕地占比)、隐蔽度因子(树冠幅、树高)以及巢生境因子(灌木占比)。总之,灰背伯劳喜好营巢于距离居民点较近、巢周围耕地面积较大的多刺灌丛。房屋和道路修建对灌丛的侵占是威胁灰背伯劳生存的主要因素。     

扎龙保护区人工林内中华攀雀巢址特征分析

作者2011年9 ～ 10月在黑龙江省扎龙国家级自然保护区对人工林内中华攀雀(Remiz consobrinus)的巢址特征进行了研究.研究期间共发现36巢,选取巢距地面距离、巢距主干距离、巢距挂枝末端距离、巢树胸径等9个巢址因子进行主成分分析.结果表明,巢下生境、巢距地面距离和巢距主干距离以及巢距挂枝末端距离在中华攀雀巢址选择中起主要作用;巢树胸径、巢向和巢挂枝年龄次之.中华攀雀巢距地面(5.59±1.44)m,距主干距离为(1.81±0.50)m,距挂枝末段距离为(0.10±0.04)m,巢树胸径(0.29±0.08)m.巢距地面高度(P =0.002 3)和巢距明水面距离(P =0.003 7)在芦苇沼泽与林地草甸2种生境类型之间差异显著,巢树胸径在林地草甸与房屋农田2种生境类型之间差异显著(P=0.003 4),不同生境类型之间巢距主干距离、巢距挂枝末端距离和巢挂枝年龄无显著差异.     

内蒙古达赉湖自然保护区狼冬季的生境选择

内蒙古达赉湖自然保护区狼的生境受到了自然环境变化压力和人为干扰的严重影响。为了解内蒙古达赉湖自然保护区狼的冬季生境特征,于2008年10-12月,在内蒙古达赉湖国家级自然保护区对狼的冬季生境选择进行了研究。野外共测量了59个20m×20m样方中的11个生态因子,运用聚类分析和主成分分析法,对狼的冬季生境选择因子进行了分析。结果表明,狼的生境主要特征为:隐蔽程度中等以上,水源距离100m,生境类型为高草阔地、干旱苇塘和河套,植被类型是以芦苇和柳灌丛为优势种的沼泽植被,植被高度1.0m,食物丰富度良好,居民点距离1000m,距草原道路距离1000m,牧场距离500m。影响狼冬季生境选择的主要因子为植被高度、植被类型和隐蔽级。次要因子为距围栏距离、雪深、距水源距离、生境类型、距牧场距离、食物丰富度和距居民点距离。     

新疆乌伦古河流域蒙新河狸巢穴特征和巢址生境选择

2014年11—12月和2015年4月,采用样方法对新疆乌伦古河流域冷季和暖季早期蒙新河狸(Castor fiber birulai)巢穴特征和巢址生境选择进行了调查研究。确定冷季160个蒙新河狸巢穴和暖季早期158个蒙新河狸巢穴,其中61个地面巢平均长(2.54±1.69)m,宽(1.68±0.91)m,高(0.54±0.32)m。与冷季相比,暖季早期蒙新河狸利用的巢穴生境具有河宽、水域面积、水深和植物郁闭度较大,河岸坡度较小的特征,是由季节更替导致的温度等气候变化引起的,而在其他生态因子选择上无差异(P0.05)。以冷季为例,蒙新河狸巢址生境选择特征表现为:(1)地理分布因子:海拔1000m,临近水域河岸1.0m、坡度75°、水深1.0m、河面宽度和面积适中;(2)隐蔽因子:巢穴隐蔽级较高,附近的植物特征(郁闭度高,乔木密度大、灌木密度低以及高度低)也辅助实现了较好的隐蔽性;(3)干扰因子:巢穴位置选择最近公路或居民点的河流异侧;(4)食物因子:巢穴多选择在密度较高的柳树林中,且距离冬季食物堆较近。建议:寻找适合蒙新河狸生存的其他潜在生境;减少在蒙新河狸生活流域修建水坝,或者在其附近修建蒙新河狸迁徙通道;加强蒙新河狸分布区的保护管理。     

四川南充市夜鹭的巢址选择

2006年3~6月,在四川省南充市太和保护区对夜鹭的巢址选择进行了研究。野外调查了夜鹭巢47个,对照样方26个,通过主成分分析和对比分析,表明影响夜鹭巢址选择的主要因子依次为:营巢树高度、植被平均高度、巢高、竹平均直径、隐蔽度、巢上方盖度、距水(西河)距离、距白鹭巢距离、植被盖度、巢下盖度。     

长尾缝叶莺和栗头缝叶莺的巢址选择比较

2013年3—6月、2014年3—6月,在广西弄岗地区对长尾缝叶莺(Orthotomus sutorius)和栗头缝叶莺(O.cuculatus)的巢址特征进行调查,以比较两者巢址选择的差异。野外共发现64个长尾缝叶莺和47个栗头缝叶莺的巢,其中长尾缝叶莺有60巢(93.7%)位于村庄林下,4巢(6.3%)位于山脚阔叶林;栗头缝叶莺有3巢(6.3%)位于村庄林下,44巢(93.6%)位于山脚阔叶林。主成分分析结果表明:影响长尾缝叶莺巢址选择的主要生态因子为筑巢植物的高度、距林缘距离和海拔;影响栗头缝叶莺巢址选择的主要因素为筑巢植物的高度、巢四周的隐蔽度和距山峰的距离。判别分析结果表明,距山峰的距离是区分2种缝叶莺巢址选择的最重要参数。     

伏牛山北坡猪獾(Arctonyx collaris)夏季巢穴特征

2005年7月和8月在伏牛山北坡调查猪獾巢穴共43个,对巢穴的海拔、植被类型、坡度、坡向、坡位、巢穴隐蔽程度、水源距离、干扰距离、郁闭度、洞口隐蔽程度、洞口数量、巢穴类型、乔木距离、灌木距离、灌木密度、倒木等16个指标进行评估.分析结果表明,伏牛山北坡猪獾夏季巢穴的选择特征是:(1)隐蔽因子,选择在巢穴和洞口的隐蔽程度、郁闭度均较高的阔叶林中;灌木密度高,乔木距离为75～150 cm.(2)地理因子,选择在海拔为900 ～1200 m的阳坡或半阳坡上,以1个洞口的石洞为主.(3)干扰因子,没有倒木,距离人类活动村落地点较近.(4)水源因子,水源距离在100 m以内.     

新疆阜康地区家麻雀的巢址选择

2013年7月和2014年5~7月,在新疆阜康地区对家麻雀(Passer domesticus)的巢址选择进行调查,以分析影响家麻雀巢址选择的生态因子。在研究区内共找到75个家麻雀的自然巢,筑巢生境为农田和防护林带,均在白杨(Populus adenopoda)林和胡杨(P.euphratica)林中的树上筑巢。其中,繁殖成功巢40个,繁殖失败巢20个,15个巢未记录到繁殖结果。在研究区内的居民房屋、墙洞等没有发现家麻雀的巢。采用逻辑斯蒂回归和主成分分析方法对筑巢地海拔(m)、筑巢树种、筑巢树高(m)、巢距路距离(m)、巢距地面高度(m)、巢上方盖度(%)、筑巢树胸径(m)、最近邻巢的距离(m)这些家麻雀的主要巢址参数进行分析,结果表明,影响新疆阜康地区家麻雀巢址利用的主要因素为巢距地面高度(m)、巢上方盖度(%)和巢距路距离(m)。对家麻雀繁殖成功巢(n=40)和繁殖失败巢(n=20)的巢址参数进行比较,两者差异不显著,因而推测,在研究区域的尺度内,家麻雀的巢址选择并不是影响其繁殖成效的主要因素。     

龙凤保护区普通鸬鹚巢特征与巢址选择

巢址选择作为鸟类繁殖的重要环节,是动物生态学关注的热点问题。为探究中等体型湿地鸟类普通鸬鹚的巢址选择偏好及主要影响因子,2019年4—10月运用秩和检验、主成分分析等方法对黑龙江龙凤保护区内普通鸬鹚巢特征、巢址特征、巢址选择进行了分析。结果表明：(1)普通鸬鹚偏好选择巢树乔木相对较矮(P<0.05)、周围灌木相对较矮(P<0.01)、植被盖度较低(P<0.01)、人为干扰距离较远(P<0.01)、距水面距离较远(P<0.05)的区域筑巢;(2)影响普通鸬鹚巢址选择的因子为隐蔽因子(20.634%)、巢稳定因子和干扰因子(27.614%)、植被因子(13.901%)、水因子(5.782%)和巢忠诚度(5.069%)。进一步分析表明：(1)普通鸬鹚倾向选择粗细适中的巢材,巢材来源于优势植被,巢深随纬度增高而增大;(2)巢区植被特征符合普通鸬鹚对能量支配的权衡,巢区粪便对该特征有强化作用。基于上述结果,建议龙凤保护区在巢区内加种高大乔木。     

郑州郊区崖沙燕(Riparia riparia)的巢址选择

2014年3—8月,采用样方法对分布于河南省郑州市郊区的4处崖沙燕(Riparia riparia Linnaeus 1758)营巢地的13个生境因子进行了调查,测定了巢址样方和对照样方各160组数据,并利用Mann-Whitney U检验对这些数据的显著水平进行了检验;最后采用逐步判别分析(stepwise discriminate analysis)方法确定影响崖沙燕巢址选择的主要生态因子,并建立了标准化的典则判别函数。结果表明,1)崖沙燕洞巢的洞口横径(8.46±0.79)cm,纵径(8.30±0.79)cm,巢洞深(87.80±11.97)cm,巢室长径(11.25±1.33)cm,短径(10.43±1.33)cm,巢室高(9.99±1.33)cm;2)巢址样方与对照样方在植被均高、植被密度、坡位、坡度、崖高、崖长、崖龄及干扰度等8个方面差异达到显著水平,崖沙燕偏好选择的洞巢周围植被较高(97.24±8.42)cm,植被密度较大(64.34±7.15)株/m~2,坡度较大(83.78±0.35)°、上坡位(1.41±0.04)、崖较高处(7.54±0.13)m、崖壁较长(51.18±3.54)m、崖龄较短(2.41±0.05)月及人类干扰较低(1.94±0.06);3)逐步判别分析结果表明,影响崖沙燕营巢地选择的主要生境因子是坡位、崖龄和干扰度,标准化的典则判别函数为y=0.753×坡位+0.681×崖龄+0.288×干扰度。建议在城市化建设过程中针对崖沙燕的巢址选择特性建立合理的保护措施。     

新疆北部白冠攀雀的巢与巢址选择

2008年4—7月,在新疆北部对白冠攀雀巢址选择进行了研究。白冠攀雀的营巢习性特殊,巢呈囊袋状,结构甚为精致。对于白冠攀雀巢的研究,采用总面积调查法,进行地毯式的搜寻,并结合标图法对其进行标记,绘制分布图。研究结果共发现巢125个,营巢位于于临近湖泊、河流等水域附近的柳树、杨树、桦树等阔叶树上。营巢树种以柳树为主,占68.80%。巢的高度平均为(5.3±2.5)m,营巢于乔木的中下部（约1/3处）,约70%的巢离河边不足30 m。对于巢址选择的研究,将原始记录中与巢址选择有关的特征变量进行主成分分析,分析表明,影响白冠攀雀巢址选择的主要因素有4种,依次为：郁闭度因素（包括营巢树胸径、巢上郁闭度）、营巢树种因素(包括营巢树种、树高、巢位高度和乔木种类)、方位因素（包括距河边距离和巢向）、食物与巢材因素。     

内蒙古达赉湖地区蒙原羚冬季采食生境选择

蒙原羚是欧亚大陆温带草原生态系统中的特有物种和数量最多的有蹄类动物。2010年11月—2011年1月,在内蒙古达赉湖地区开展了蒙原羚冬季采食生境选择研究。结果表明:蒙原羚冬季选择利用雪深<6cm,地上生物量>50g.m-2,距围栏1000～2000m,植被高度>20cm,植被盖度>40%,隐蔽条件(可视距离)3000～4000m,到居民点距离>2000m,距家畜>2000m,坡度<20°,中上坡位,针茅(Stipa spp.)和羊草(Aneurolepidium chinnenses)等植被类型的生境采食;生境因子综合影响蒙原羚的冬季采食生境选择,依照贡献值的大小依次为到围栏距离、地上生物量、雪深和隐蔽条件。逐步判别分析表明,由这4个变量构成的判别方程在对蒙原羚采食样方进行区分时,正确判别率为82.1%。因此,建立合理的围栏管理制度、提高可利用食物量等是蒙原羚保护的关键。     

The influence of nest-site characteristics on the nesting success of the Karoo Prinia (Prinia maculosa)

Choice of nest site has important consequences for nest survival. We examined nest-site characteristics relative to nest success in Karoo Prinias breeding in coastal dwarf shrubland, where high nest predation is the main cause of nest failure. Initially, we compared nests that failed during the building, laying, incubation and nestling stages and those from which young were successfully raised, to test whether nests that survived to progressive stages in the nesting cycle differed in their nest-site characteristics. Subsequently, we compared the characteristics of successful nests with those of unsuccessful nests. The nest-site characteristics considered included nest height, nest-plant height, nest-plant species, distance from lateral foliage edge, nest concealment, nest-patch heterogeneity and vegetation cover at four different heights. We were unable to distinguish between the nest-site characteristics of nests that failed during the various stages of the nesting cycle. Concealment was the main nest-site characteristic that differentiated successful nests from unsuccessful nests, with successful nests being located in more concealed sites. The other variables that contributed to the discrimination between successful and unsuccessful nests by discriminant function analysis included nest-plant type and distance from edge, which are also directly related to concealment. This suggests that nest concealment is the most important variable influencing nesting success at this site, which has a preponderance of visually-oriented predators.     

Nest survival of piping plovers at a dynamic reservoir indicates an ecological trap for a threatened population

In the past 60 years, reservoirs have reshaped riverine ecosystems and transformed breeding habitats used by the threatened piping plover (Charadrius melodus; hereafter plover). Currently, 29 % of the Northern Great Plains plover population nests at reservoirs that might function as ecological traps because reservoirs have more diverse habitat features and greater dynamics in water levels than habitats historically used by breeding plovers. We examined factors influencing daily survival rates (DSR) of 346 plover nests at Lake Sakakawea (SAK; reservoir) during 2006–2009 by evaluating multiple a priori models, and we used our best model to hindcast nest success of plovers during 1985–2009. Our observed and hindcast estimates of nest success were low compared to published estimates. Previous findings indicate that plovers prefer nest sites that are low relative to water level. We found that elevation of nests above the water level had a strong positive correlation with DSR because water levels of SAK typically increased throughout the nesting period. Habitat characteristics on the reservoir differ from those that shaped nest-site selection for plovers. Accordingly, extraordinary nest loss occurs there in many years, largely due to inundation of nests, and based on low fledging rates those losses were not compensated by potential changes in chick survival. Therefore, our example supports the concept of ecological traps in birds because it addresses quantitative assessments of habitat preference and productivity over 25 years (since species listing) and affects a large portion of the population.     

Factors Affecting Songbird Nest Survival in Northern Mixed-Grass Prairie

ABSTRACT Factors associated with the nest survival of mixed-grass prairie passerines are not well known, especially in the context of contemporary grassland management. We documented the nest survival of clay-colored sparrows (Spizella pallida), savannah sparrows (Passerculus sandwichensis), and bobolinks (Dolichonyx oryzivorus) in managed prairie in northwestern North Dakota, USA. We used logistic exposure models and an information-theoretic framework to estimate nest survival and evaluate support for mechanisms (grazing, temporal factors, nest parasitism, nest-site vegetation, and nest-patch factors) relevant to nest survival. Survival for the entire nesting interval (23–28 days) was low for clay-colored sparrow (18.2%), savannah sparrow (15.5%), and bobolink (3.5%). We found support for a cubic effect of nest age; survival of savannah and clay-colored sparrow nests was greatest during mid-incubation and least during the mid-nestling period. Parasitized clay-colored sparrow and bobolink nests had greater survival rates than nonparasitized nests. Nest survival of clay-colored sparrows increased with increasing vegetation height and density. For savannah sparrows, nest survival was lower when cattle were present than when cattle were absent. Characteristics of the nest patch did not have strong effects based on model coefficients and confidence intervals, though they appeared in many of the most supported models. Positive effects of vegetation height and density on nest survival of clay-colored sparrows and negative effects of cattle presence on nest survival of savannah sparrows suggest some detrimental effects of grazing. However, the need to restore and maintain intact prairies likely warrants the continuation of cattle grazing on conservation lands.     

Nest location, clutch size and nest success in the Scarlet Ibis Eudocimus ruber

Breeding success and nest-site characteristics were studied during the 1996–1997 breeding season in a colony of Scarlet Ibises Eudocimus ruber in south-eastern Brazil to test the hypothesis that nest-site characteristics and clutch size affect nest success. Two nesting pulses produced young, the earlier being more successful. Predation accounted for most failures during the first pulse, wind destruction during the second. A third pulse with few nests produced no young. Adult Ibises abandoned nests when they lost sight of other incubating birds. Logistic regression analysis indicated that nest success during the first pulse was positively related to clutch size, number of nests in the nest tree and in the nearest tree, and negatively to the distance to the nearest neighbour. During the second pulse there were significant negative associations between success, nest height and distance to the fourth nearest nest, and a positive association between success and nest cover. The results agree with the 'selfish herd' hypothesis, indicating that nest aggregation may increase breeding success, but the nest-site characteristics affecting success can differ over the course of one breeding season.