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1.
皮质酮是鸟类重要的糖皮质激素,在其适应环境变化及压力应激反应中起重要的调节作用。非应激状态时,鸟类血浆皮质酮浓度处于基线水平,当鸟类面对应激刺激时,血浆皮质酮浓度迅速升高,应激水平的皮质酮对鸟类个体生存至关重要。然而,目前繁殖季鸟类血浆应激水平的皮质酮浓度变化及其与繁殖投入关系的研究结果存在种间差异,仍需在不同的物种中进行实验研究。本研究分析了繁殖季杂色山雀(Sittiparus varius)血浆应激水平的皮质酮浓度在繁殖阶段的变化,及育雏期亲鸟血浆应激水平的皮质酮浓度与繁殖参数和亲鸟育雏投入的关系。结果显示,与求偶期相比,育雏期杂色山雀亲鸟血浆应激水平的皮质酮浓度极显著升高(P < 0.001),雌性与雄性亲鸟之间无显著性差异(P > 0.05);雌性与雄性亲鸟血浆应激水平的皮质酮浓度与繁殖参数、亲鸟递食投入、巢防卫行为均无显著相关性(P > 0.05)。  相似文献   
2.
新疆北部白冠攀雀的巢与巢址选择   总被引:1,自引:0,他引:1  
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。  相似文献   
3.
Capsule Woodland birds were significantly less likely to occur in gardens in years of high beechmast crop.

Aim To test the hypothesis that woodland species that feed on beechmast will have significantly lower occurrence rates at garden feeders in mast years.

Methods Weekly winter occurrence rates at garden feeders between 1970/71 and 1999/2000 for 40 species were analysed in relation to annual beechmast abundance, classified into low, medium and high years. A repeated-measures logistic regression model was used to assess whether beechmast abundance explained further significant variation additional to underlying seasonal and annual trends.

Results Seven species that commonly feed on beechmast showed significantly lower occurrence in gardens in years of highest beechmast abundance: Great Spotted Woodpecker Dendrocopos major, Woodpigeon Columba palumbus, Great Tit Parus major, Coal Tit Periparus ater, Nuthatch Sitta europaea, Jay Garrulus glandarius and Chaffinch Fringilla coelebs. Blackbird Turdus merula and Siskin Carduelis spinus, which showed similar significant patterns, are likely to take beechmast as elements of their diet. Pied Wagtail Motacilla alba was the only insectivorous species to show significant effects, but occurrence was lowest in years of intermediate beechmast abundance. For the latter species, this may have been due to confounding effects of temperature, but there were no such confounding effects of either temperature, or the number of bird feeders provided in gardens, for the other nine species.

Conclusion Use of artificial food sources by birds in gardens is influenced by resources in the surrounding countryside, suggesting that food provided in gardens may play a significant part in the population dynamics of these species, that population monitoring without consideration of the garden habitat may be deficient, and that volunteer-based garden bird recording may provide data that can be used as an indicator of changes in the wider countryside.  相似文献   
4.
Woodland birds have experienced widespread population declines across Europe, resulting partly from a decrease in management practices such as coppicing. Increasing fuelwood demand may reverse the decline of coppicing, making it timely to attempt a fuller understanding of its effects. Here, the impact of coppicing on year‐round habitat use by adults and juveniles of 16 songbird species was quantified from a quasi‐experimental study over 32 years (1978–2009) in Treswell Wood, Nottinghamshire, UK. Habitat use was inferred using capture rates from more than 10 000 h of mist‐netting (> 25 000 captures) and detailed information on coppicing. Capture rates varied with coppice age in different ways: (1) increases as coppice aged (e.g. Marsh Tit Poecile palustris, juvenile Eurasian Treecreepers Certhia familiaris); (2) declines as coppice aged (e.g. Eurasian Blue Tit Cyanistes caeruleus, Great Tit Parus major); (3) peaks in capture rates at intermediate coppice age (i.e. 5–15 years) (e.g. Garden Warbler Sylvia borin, Willow Warbler Phylloscopus trochilus, adult Treecreepers); and (4) a peak at intermediate ages, followed by a decline, before an increase in use again at the oldest coppice ages (i.e. > 20 years) (e.g. Common Blackbird Turdus merula, Eurasian Blackcap Sylvia atricapilla, Eurasian Bullfinch Pyrrhula pyrrhula). Responses to coppice age were similar in different seasons, although Willow Tits Poecile montana showed little preference during breeding but avoided older coppice at other times. Juveniles and adults often differed in their responses to coppice age. The analyses reveal patterns in habitat use that are relevant to woodland management and conservation policy. They suggest that a mosaic of age structures in woodland is beneficial to a wide range of woodland species, and that management should consider the requirements of all age‐classes of birds at different times of year.  相似文献   
5.
Jolyon Troscianko 《Ibis》2014,156(4):874-878
The geometrical properties of eggs – such as volume and surface area – have uses ranging from ecological, physiological and morphological studies in birds, to predictions of chick condition in the poultry industry. Although measurements of an egg's length and breadth can be used to approximate its geometry, the coefficients used in these models are specific to the original test population, and intraspecific variation in egg shape means these methods cannot be used reliably beyond that population. Here I present a novel mathematical formula to describe the curvature of a bird's egg that can be used to calculate the shape, volume and surface area of an egg precisely from digital images. Using data from several species I demonstrate that the model has a greater level of accuracy than length‐ and breadth‐based methods, and release the user‐friendly tool for others to use for measuring eggs from digital images.  相似文献   
6.
The current study examined the economics of cooperation in controlled-payoffgames by using captive blue jays, Cyanocitta cristata. Thisinvestigation used a special feeding apparatus to test for thestability of cooperative choice in a series of iterated games.The jays experienced experimentally determined game theoreticalpayoff matrices, which determined the distribution of food tothemselves and their opponent, depending on their decision tocooperate or defect. The experiment tested four game matrices,called the cooperate only, defect only, prisoner's dilemma,and opponent control treatments. This study found little cooperationin the defect only and prisoner's dilemma treatments. Cooperationoccurred significantly more often in the opponent control treatment.These findings suggest that the jays attend to short-term consequences;they do not cooperate in the absence of an immediate benefit(defect only), even if a long-term benefit may exist (prisoner'sdilemma). The opponent control treatment suggests that cooperationcan occur when an individual's benefits depend completely onthe actions of others; therefore, generosity is cheap. Thisstudy, therefore, agrees with recent studies in proposing alternativemodels of cooperation.  相似文献   
7.
Knowledge of cooperative breeding in birds from longitudinal studies is available only for a small proportion of species. This paper reports data from a 12‐year study on the Tibetan Ground Tit Pseudopodoces humilis. On average, 27.2% (range: 13.0–36.1%) of monogamous pairs in each year contained one (85.4%) or more (14.6%) male helpers, 83.7% of which were yearlings staying on natal territories. Most helpers (89.6%) helped once and then bred independently. Adults had male‐biased sex ratios, low annual survival rates (averaging 0.50) and shorter longevities (averaging 1.8 years) compared with low‐altitude avian cooperative breeders, suggesting that mate shortage promotes helping behaviour in this species. Incest occurred rarely (2.1% of pairs), probably because kin recognition occurs through year‐around living in family groups. There was a low level (3.1% of broods) of extra‐pair parentage, which could facilitate the maintenance of cooperative breeding.  相似文献   
8.
黑冠山雀(Parus rubidiventris)和煤山雀(P.ater)在瓦屋山同域分布,生态位相似,是潜在的竞争者。在垂直分布上,煤山雀的生态位宽度为5.237,显著高于黑冠山雀的2.792,而在水平分布和活动基质2个维度上,二者的生态位宽度值相当。尽管3个维度上2种山雀生态位重叠值均大于0.7,但是它们对3个维度上的资源利用分别存在不同的偏好和侧重。2种山雀的身体量度除了喙宽外均有极显著差异,这应该是2种山雀对环境适应的结果。这2种山雀在巢址选择上各项参数差异均不显著,表明适宜的洞巢可能是它们种间竞争的主要对象。2种山雀的种群数量可能与居留类型有关。空间生态位或食物生态位的分离及适宜的种群数量和比例是它们得以共存的几个重要因素。  相似文献   
9.
杂色山雀对人工巢箱内苔藓类巢材的选择   总被引:1,自引:0,他引:1  
2008年及2009年每年的3~8月,在辽宁省仙人洞国家级自然保护区对杂色山雀(Parus varius)人工巢箱内苔藓类巢材进行了收集和鉴定,发现巢中共有藓类植物7科9属。其中,小锦藓属(Brotherella)、青藓属(Brachytheccium)、棉藓属(Plagiothecium)及绢藓属(Entodon)所占比重较大。我们分别按照样方和苔藓群落采集了周围环境中的藓类植物,鉴定出7科8属的藓类植物;采集到35个苔藓群落,出现最多的是东亚小锦藓(B.fauriei)群落。结果显示,杂色山雀对苔藓的选择可能与苔藓的生物学特性、分布和数量有关。另外通过统计分析和比较得出,按照苔藓群落来采集的方式更适合本文的研究。  相似文献   
10.
2016和2017年,采用焦点动物取样法及全事件记录法,在新疆和静县巴仑台镇研究了4个繁殖巢的秃鹫(Aegypius monachus)繁殖行为。通过红外相机和人工观察,构建了秃鹫巢内育雏期的行为谱,将秃鹫亲鸟的行为划分为9类33种,将雏鸟行为划分为6类28种。结果表明,亲鸟喂食次数的最高峰出现在12:30~13:30时,随后在15:30~18:30时之间出现一个小高峰。在育雏期,亲鸟行为以护幼、观望和警戒为主,雏鸟则以休息和观望为主。将巢内育雏期分为三个阶段:育雏前期(4~5月)、育雏中期(6月)、育雏后期(7月),运用单因素方差分析(one-way ANOVA)检验不同育雏阶段亲鸟、雏鸟行为时间分配的差异。结果显示,育雏前期与后期之间亲鸟的行为时间分配差异不显著(P0.05),前期与中期和中期与后期之间,亲鸟的行为时间分配差异均显著(P0.01);育雏前期、中期与后期的雏鸟行为时间分配差异均显著(P0.01)。国内秃鹫繁殖主要面临食物短缺、人类活动干扰等威胁。  相似文献   
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