四川雅江县四川雉鹑的生活习性

四川雉鹑Tetraophasis szechenyii是我国的特有种,国家一级保护动物,分布区狭窄。在四川省雅江县调查了四川雉鹑的栖息环境、种群数量,活动规律、食性等生活习性。四川雉鹑主要栖息于针叶林,针叶林内遇见率最高,在旁母林南坡种群密度高于北坡,其食物以植物为主,昼间大都3-5只集群活动, 夜晚栖息在树上。调查区种群密度为3-11只/km^2,在雅江地区四川雉鹑的数量相对较多,这可能与该地的地理环境和气候有关,同时还与得力的保护措施有关。     

雉鹑和绿尾虹雉的羽毛数

经有关部门批准,作者在四川白河保护区剖析了6只雉鹑(3(?)(?)3♀♀)和5只绿尾虹雉 (3(?)(?)2♀♀),统计了这两种鸡类的羽毛数。 统计结果:雉鹑5516—6592,绿尾虹雉为9061—10159。     

利用PCR鉴定四川雉鹑性别

四川雉鹑是我国特有珍稀濒危雉类,为国家Ⅰ级保护动物.本文通过设计引物,扩增四川雉鹑W染色体上雌性特异基因HINTW,利用PCR产物有无对其进行性别鉴定,发现在四川雉鹑中雄性个体无阳性产物,而雌性扩增出500 bp和300 bp 2条条带.应用通用引物扩增四川雉鹑基因组CHD基因,其中雄性个体扩增出约500 bp的条带,而雌性个体则扩增出500 bp和750 bp 2条条带,通过其Z/W染色体上基因片段长度差异可进行性别鉴定.上述两种方法对9个四川雉鹑的性别鉴定结果均一致.     

四川雉鹑繁殖习性初报

2005～2008年,在四川省雅江县对四川雉鹑(Tetraophasis szechenyii)的繁殖习性,包括巢、卵、孵卵时间、生长量度和日行为节律进行了初步观察.四川雉鹑同时营树上巢和地面巢,以树上巢为主,占68%(n=25);产卵期集中在4月,正常窝卵数2～5枚(n=9),窝卵孵化率为63.89%(n=12);雌鸟在孵卵期每天离巢1次,离巢平均时间(63.0±22.6)min(n=18),孵卵期24～29 d(n=4);150日龄幼鸟的体重接近成体.在繁殖期,四川雉鹑6:30～7:00时从夜栖树上飞下,行至觅食地觅食,17:00时左右返回夜栖地,19:00～19:30时上树夜栖.     

夏秋季四川雉鹑植物类食物资源及其分布

2006年6月～2009年10月,采用直接观察法和样带样方法在四川省雅江县帕姆岭对四川雉鹑夏秋季的植物性食物及其资源分布状况进行了调查.四川雉鹑采食的植物种类有34种,其中草本植物32种,木本植物2种.在夏季取食的种类有28种,秋季18种,两个季节同时取食的植物种类有12种.四川雉鹑取食强度高的物种有15种,中度的有11种,低度的有8种.夏季四川雉鹑主要取食草本植物的叶与根茎,秋季主要采食的是成熟的种子和果实.在不同生境类型中四川雉鹑的食物组成与丰富度存在差异,光亮杜鹃灌丛和高山杂草类草甸生境的食物种类和食物总量都相对较高,是四川雉鹑的食物基地,而鳞皮冷杉-川滇杜鹃林和高山松林的食物种类和数量相对较低.     

血雉分类地位和遗传分化的探讨

长期以来对血雉Ithaginis应划归雉类还是鹑类和是多型属还是单型属一直存在着争议.在此对3个亚种,西藏亚种Ithaginis cruentus tibetanus,甘肃亚种I.c.berezawskii和四川亚种I.c.geoffroyii的6个个体的血雉与典型的雉类雉属Phasiamus、锦鸡属Chrysolophus、长尾雉属Syrmaticus及典型的鹑类石鸡属Alectoris、鹌鹑属Coturnix和雪鸡属Tetraogallus的线粒体DNA细胞色素6的部分基因序列比较,系统进化树中血雉与雉类聚在一起.根据血雉地理分布,多亚种中心理论,区域地理历史,环境演变和分子钟指示的时间,血雉可能于早上新世起源于横断山脉.3个亚种之间序列差异为4.1%-7.2%,与雉科其它属的种问差异度比较,其遗传分化已达到种的水平,与形态差异相吻合.     

以线粒体DNA Cytb确立红喉雉鹑和黄喉雉鹑的分类地位

采用PCR技术获得红喉雉鹑Tetraophasis obscurus和黄喉雉鹑Tetraophasis szechenyii等物种的828 bp Cytb基因片段,雉鹑属Tetraophasis可变位点为26个,并用MEGA3和K-Estimator 6.1软件进行了序列分析.研究发现红喉雉鹑和黄喉雉鹑之间序列差异为3.0%～3.1%,与其它属种间序列差异相比较,两种雉鹑之间的序列差异达到了种的水平;它们地理分布互相替代;形态差异稳定.地理分布、形态特征和遗传特征均验证了它们应为两个独立的种.依据分子进化速率推测,两种雉鹑分歧时间距今2.0Myr左右,与早更新世冰期发生的时间一致.雉鹑起源于青藏高原,随着青藏高原的抬升,早更新世冰期气候变冷,寒温性针叶林的林线下移,大面积高原草甸出现,雉鹑的祖先种群被隔离进化,而形成了两种雉鹑.     

四川雉鹑的冬季夜栖地选择

四川雉鹑(Tetraophasis szechenyii)是中国特有物种,国家Ⅰ级重点保护野生动物,对其冬季夜栖地选择的了解,有助于理解物种的生存策略,为物种保护提供参考。利用徒步跟踪和无线电遥测的方法,我们于2006年9月到2007年4月在四川省雅江县帕姆岭进行了野外研究。采用卡方检验、配对样本t检验和二元逻辑斯缔回归等方法对数据进行分析。结果发现:(1)四川雉鹑利用鳞皮冷杉(Abies squamata)和大果红杉(Larix potaninii var.macrocarpa)两种树夜栖,卡方检验分析发现四川雉鹑对这两树种没有明显的选择偏好(χ2=0.745,df=1,P=0.388);(2)夜栖树的胸径为(25.8±1.3)cm,夜栖枝条离地高度为(6.3±0.3)m,直径为(3.3±0.1)cm;(3)与对照样地相比,夜栖地生境一般靠近林缘,乔木的平均胸径大、林下盖度小、倒木数量多,夜栖树胸径大、最近乔木胸径大和最近乔木距离远;(4)逻辑斯缔回归分析表明:夜栖树第一枝距地面高为冬季四川雉鹑夜栖地选择的关键因子;倒木数量、平均乔木胸径、最近林缘距离为次关键因子,该模型对夜栖地的预测正确率为80.9%。冬季四川雉鹑选择夜栖地是安全、能量和地点转移三个因素综合作用的结果,在不同的环境下,同一物种对环境会有不同的适应策略。     

四川卧龙国家级自然保护区三种高山同域鸡形目鸟类的时空生态位比较

高海拔山区气候条件恶劣, 资源匮乏, 探究同域分布的近缘物种如何利用有限的资源以实现稳定共存, 对于了解高山生态系统生物多样性格局的形成和维持机制具有重要意义。鸡形目鸟类飞行能力弱, 属于典型的地栖物种, 生态位空间相对狭窄, 可能面临更高的种间竞争压力。本研究旨在比较几种同域分布的鸡形目鸟类的时空生态位, 为了解高山生态系统同域物种的共存机制提供新的研究案例。2020年4-9月, 研究人员在四川卧龙国家级自然保护区海拔3,300-4,200 m的高山区域进行了野外调查, 通过样线法和样方法对鸡形目鸟类群落优势物种绿尾虹雉(Lophophorus lhuysii)、雉鹑(Tetraophasis obscurus)和雪鹑(Lerwa lerwa)繁殖期的微生境进行调查, 使用红外相机对其活动节律进行监测, 并运用核密度估计法从微生境利用和日活动节律两个生态维度进行了种间生态位比较。结果显示, 雪鹑在微生境利用和日活动节律上均与其他两个物种存在显著差异。绿尾虹雉与雉鹑在微生境的利用上具有相似偏好; 但绿尾虹雉的早活动高峰晚于雉鹑, 晚活动高峰早于雉鹑, 表现出显著的种间日活动节律差异; 然而, 整合两个维度后, 绿尾虹雉和雉鹑的整体生态位仍然高度重叠, 没有显著分化。本研究表明高山鸡形目物种间的生态位分化体现于多个不同的生态维度, 并且不同物种之间的分化方式有所差异。在空间和时间生态位上的显著分化使雪鹑与同域物种间的竞争压力相对较小, 有利于其实现稳定共存。而绿尾虹雉与雉鹑的整体生态位高度重叠, 建议进一步对其食性开展研究, 探讨营养生态位上的潜在种间分化。     

四川王朗国家级自然保护区红喉雉鹑的日活动节律及种群密度

红喉雉鹑Tetraophasis obscurus是我国特有高山雉类,国家一级重点保护野生动物。为了解其生活习性及种群参数,2020—2021年在四川王朗国家级自然保护区采用红外相机技术、样线法和样点法对红喉雉鹑的日活动节律及其种群密度进行了调查。红喉雉鹑在保护区分布海拔为2 773～3 777 m,主要活动在3 200～3 400 m,常见于针叶林和针阔混交林,未在草甸生境中记录到;核密度函数绘制的日活动节律曲线表明,红喉雉鹑为昼行性动物,全年日活动曲线整体呈单峰模式,日活动强度在06∶00后快速升高,在08∶00—10∶00达到最高,之后快速降低至12∶00,其后缓慢下降,20∶00趋近于无;繁殖季和非繁殖季的日活动节律均呈双峰模式,但差异不显著（Δ=0.79）,均以早晨最为活跃,非繁殖季比繁殖季的活动高峰推迟1～2 h;红外相机拍摄的群体平均大小为2.63只/群,样线调查的为3只/群,样线法和样点法估算的种群密度分别为7.60只/km²和5.42～6.18只/km²。本研究丰富了红喉雉鹑的野外生态学资料,为其保护管理和种群监测、评估提供...     

State-dependent incubation behaviour in the zebra finch

State dependence is thought to be an important factor in resource allocation decisions, particularly in those decisions relating to parental care. Incubation behaviour is a costly part of avian parental care, and therefore likely to depend on the parent's body condition. We manipulated the body condition of zebra finches, Taeniopygia guttata, during incubation by using prelaying diets of different protein content, and induced birds to lay a similar number of eggs. We tested the hypothesis that birds in better body condition would invest more in incubation than birds in poorer condition when incubating on the same diet. Females that had received a high-protein prelaying diet lost more body mass than those that had received a low-protein diet. They also increased the length of their incubation bouts between early and middle incubation, whereas females that had received a low-protein prelaying diet increased bout length only between middle and late incubation. There were no differences between males from the two diet groups, and males were responsible for a lesser proportion of incubation than females. These results indicate that incubation behaviour is state dependent in female zebra finches, and that birds of different body condition adopt different incubation strategies. We found no differences in incubation duration and hatching success between the two incubation strategies in captivity, but the potential risk of nest predation in the wild may differ. We suggest that only females in good condition can afford to adopt a strategy of increasing bout length early in incubation; females in poorer condition first have to recover their body condition after having produced a clutch. Copyright 2003 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour       

Experimental dissociation of the effects of diet, age and breeding experience on primary reproductive effort in zebra finches Taeniopygia guttata

Reproductive performance varies with age in a wide range of organisms, and increasingly such patterns are interpreted in terms of state-dependent models. We sought to characterise 'state' with regards to age-related variation in clutch size, egg mass and timing of breeding in captive zebra finches Taeniopygia guttata , focusing on the roles of diet quality, age and breeding experience. Females on a high-quality diet laid larger clutches of larger eggs than did females on a low-quality diet. The effect of age on reproductive performance was examined by comparing females breeding (i.e. paired) for the first time at either 3- and/or 6-months of age. Clutch size increased with age but on the low-quality diet only, not on the high-quality diet. Furthermore, clutch size decreased between 3- and 6-months of age in birds bred first on the high-quality diet and then on the low-quality diet. Age did not affect egg mass but older birds had shorter laying intervals. Reproductive performance did not differ between females breeding at 6-months of age for the first or second time: the effects of age were not due to 'training' effects or experience specific to breeding (e.g. undergoing the physiological process of egg formation). In conclusion, nutritional condition (diet) emerged as a central component of state that could strongly influence, and even reverse, any age-dependent increase in primary reproductive performance.     

A contribution to the ecology and reproductive biology of the Marabou stork (Leptoptilos crumeniferus) in East Africa

Marabous are common scavengers in regions where game or domestic animals are abundant or near human settlements. Adults are able to subsist for long periods on a diet of carrion, but the rapidly growing nestlings require a high-calcium diet containing some small whole vertebrates, such as fish or frogs. Most breeding colonies are situated near a source of carrion as well as a freshwater feeding area. Breeding generally takes place in the dry season, when aquatic vertebrates are concentrated and carrion is easier to obtain. Observations are presented on the various phases of the breeding cycle. The incubation period averaged 30–3 days, and the young stayed in the nest an average of 116 days before their first flight. Parents commonly bring water, as well as food, to young in the nests. Only a small percentage of the population appears to breed in any given year, and the rate of productivity is low; some birds must live to be very old. Population size is probably controlled by food availability and its influence on reproductive success.     

Physiological and Ecological Correlates of Prolonged Incubation in Sea Birds

Sea birds with long incubation periods are identified, togetherwith the features of their incubation physiology which distinguishthem from birds in general. Most sea birds with prolonged incubationare members of the order Procellariformes. The majority of Pelecaniformesand Charadniformes with long incubation periods are tropicalspecies. The total amount of water lost from the egg duringincubation is a similar fraction of the initial egg weight insea birds with prolonged incubation as in other birds. The oxygenconsumption of the newly hatched chick is similarly relatedto the chick weight, regardless of the duration of incubation.Within the constraints imposed by these similarities, sea birdswith prolonged incubation display a number of adaptations. Thedaily rate of water loss from the egg, the water vapor conductanceof the egg shell, and the total functional pore area of theegg are all relatively low in sea birds with prolonged incubation.The eggs of sea birds with long incubation times are large inrelation to the size of the adult bird in the two species thathave been studied, the high energy content of the egg is paralleledby the greater total amount of oxygen consumed during incubation.However, the growth of the embryo is relatively slow in at leastone sea bird with a long incubation time so that prolonged incubationprobably entails a comparatively high allocation of energy resourcesto maintenance requirements. In some species with prolongedincubation, the interval between pipping and hatching is alsolong and it appears to be a period of great physiological importance.Ecologically prolonged incubation is associated with eitherpelagic feeding habits or a tropical environment, both factorsmay be related to food supply.     

Elevational range and timing of breeding in the birds of Ladakh: the effects of body mass, status and diet

We studied the effects of body mass, status (resident or migratory) and diet on the breeding elevation range and timing of reproduction of the birds in the Trans-Himalayan region of Ladakh, northwestern India. Most of breeding birds of Ladakh are Palearctic or breed at high elevations in the mountains. There is a small proportion of Oriental species, and no bird is endemic to this region. We found that heavier birds tended to start their egg-laying earlier than lighter ones. Since body mass is related to the length of incubation and nesting periods, it would appear that one result of this phenomenon is that the time of peak demand for food for most birds coincides with peak food abundance in summer. Status affected the elevation of the breeding range, with resident birds tending to breed at higher elevations than summer visitors. Residents and summer breeders also differed significantly in their diet composition, with the former feeding mainly on plants and seeds, and the latter feeding on molluscs, insects and worms.     

Getting a head start: diet, sub-adult growth, and associative learning in a seed-eating passerine

Developmental stress, and individual variation in response to it, can have important fitness consequences. Here we investigated the consequences of variable dietary protein on the duration of growth and associative learning abilities of zebra finches, Taeniopygia guttata, which are obligate graminivores. The high-protein conditions that zebra finches would experience in nature when half-ripe seed is available were mimicked by the use of egg protein to supplement mature seed, which is low in protein content. Growth rates and relative body proportions of males reared either on a low-protein diet (mature seed only) or a high-protein diet (seed plus egg) were determined from body size traits (mass, head width, and tarsus) measured at three developmental stages. Birds reared on the high-protein diet were larger in all size traits at all ages, but growth rates of size traits showed no treatment effects. Relative head size of birds reared on the two diets differed from age day 95 onward, with high-diet birds having larger heads in proportion to both tarsus length and body mass. High-diet birds mastered an associative learning task in fewer bouts than those reared on the low-protein diet. In both diet treatments, amount of sub-adult head growth varied directly, and sub-adult mass change varied inversely, with performance on the learning task. Results indicate that small differences in head growth during the sub-adult period can be associated with substantial differences in adult cognitive performance. Contrary to a previous report, we found no evidence for growth compensation among birds on the low-protein diet. These results have implications for the study of vertebrate cognition, developmental stress, and growth compensation.     

The demands of incubation and avian clutch size

We reviewed information on the demands of incubation to examine whether these could influence the optimal clutch size of birds. The results indicate that appreciable metabolic costs of incubation commonly exist, and that the incubation of enlarged clutches can impose penalties on birds. In 23 studies on 19 species, incubation metabolic rate (IMR) was not elevated above the metabolic rate of resting non-incubating birds (RMR), but contrary to the physiological predictions of King and others, IMR was greater than RMR in 15 studies on 15 species. Across species, IMR was substantially above basal metabolic rate (BMR), averaging 1.606 × BMR. Of six studies on three species performed under thermo-neutral conditions, none found IMR to be in excess of RMR. IMRs measured exclusively within the thermo-neutral zone averaged only 1.08 × BMR contrasting with the significantly higher figure of 1.72 × BMR under wider conditions. 16 of 17 studies on procellariiforms found IMR below RMR, indicating a significant difference between this and other orders. We could find no other taxonomic, or ecological factors which had clear effects on IMR. Where clutch size was adjusted experimentally during incubation, larger clutches were associated with: significantly lower percentage hatching success in 11 of 19 studies; longer incubation periods in eight of ten studies; greater loss of adult body condition in two of five studies; and higher adult energy expenditure in eight of nine studies. Given that incubation does involve metabolic costs and given that the demands of incubation increase sufficiently with clutch size to affect breeding performance, we propose that the optimal clutch size of birds may in part by shaped by the number of eggs the parents can afford to incubate.     

Prenatal developmental conditions have long-term effects on offspring fecundity

Maternal effects, in which differences in parental state cause differences in offspring fitness, are important in trade-offs influencing an individual's optimal reproductive strategy. In zebra finches (Taeniopygia guttata) we manipulated the nutritional state for four weeks before the start of breeding through protein supplementation. Zebra finches were kept on identical diets during the rest of the experiment. We then tested the effects of maternal state on offspring size, survival and fecundity. In order to separate the effects of maternal state occurring through egg production, incubation and chick-rearing, we used a cross-fostering experiment. We show that a protein-rich diet prior to laying improved maternal body weight prior to breeding compared with birds on a protein-poor diet. Poorer maternal state prior to breeding gave rise to offspring with lower fecundity than offspring from birds in a better nutritional state. Maternal state is thought to affect the conditions developing offspring experience through the bird's ability to produce and incubate eggs. Male and female embryos differed in their responses to conditions at different developmental stages. This shows that embryonic developmental conditions and sex differences in vulnerability to these conditions need to be incorporated into future models of selection, life-history evolution and sex-ratio theory.     

Do T3 levels in incubating eiders reflect the cost of incubation among clutch sizes?

Complete development of avian eggs requires external heat, inducing in most species an energetic cost of incubation for the parents. Triiodothyronine (T(3)) has been implicated in the control of the metabolic rate and is decreased during fasting in most bird species. This raises the question of the regulation of T(3) during reproduction when incubation (thus heat production) is associated with fasting (and energy sparing). In this study, plasma concentrations of T(3) were studied for different clutch sizes in incubating, as well as in nonincubating, fasting female eiders. Our results show that the T(3) levels decrease during fasting in nonincubating birds, whereas they were maintained during the incubation fast. T(3) levels increased in female eiders at hatching. The plasma T(3) level did not vary among natural clutch sizes in eiders but did so when manipulated. T(3) levels increased when eggs were added (to a maximum of six eggs, i.e., the biggest natural clutch size) or removed (to two eggs, i.e., the smallest natural clutch size). Our results suggest that (1) high T(3) levels during incubation may participate to a threshold of heat production and incubation metabolic rate in eiders despite the fact that they are fasting; (2) since T(3) is associated with the energy expenditure in birds, incubating an enlarged or reduced clutch size may lead to a higher energetic cost of incubation in eiders; and (3) the energy demand of the ducklings at hatching is probably important, as the female T(3) concentrations are then at their highest levels. Thus, any modification of the natural clutch size leads to a rise in the T(3) level of the incubating female, suggesting an additional cost of incubation. Knowing that there is no variation of T(3) levels among natural clutch sizes, this study suggests that a female eider produces a number of eggs corresponding to the energy she can invest in incubation.     

The evolution of egg shape in birds: selection during the incubation period

A recent broad comparative study suggested that factors during egg formation – in particular ‘flight efficiency’, which explained only 4% of the interspecific variation – are the main forces of selection on the evolution of egg shape in birds. As an alternative, we tested whether selection during the incubation period might also influence egg shape in two taxa with a wide range of egg shapes, the alcids (Alcidae) and the penguins (Spheniscidae). To do this, we analysed data from 30 species of these two distantly related but ecologically similar bird families with egg shapes ranging from nearly spherical to the most pyriform eggs found in birds. The shape of pyriform eggs, in particular, has previously proven difficult to quantify. Using three egg‐shape indices – pointedness, polar‐asymmetry and elongation – that accurately describe the shapes of all birds’ eggs, we examined the effects of egg size, chick developmental mode, clutch size and incubation site on egg shape. Linear models that include only these factors explained 70–85% of the variation in these egg‐shape indices, with incubation site consistently explaining > 60% of the variation in shape. The five species of alcids and penguins that produce the most pyriform eggs all incubate in an upright posture on flat or sloping substrates, whereas species that incubate in a cup nest have more spherical eggs. We suggest that breeding sites and incubation posture influence the ability of parents to manipulate egg position, and thus selection acting during incubation may influence egg‐shape variation across birds as a whole.