崇明东滩鸻鹬类迁徙路线的环志分析

崇明东滩为东亚-澳大利西亚鸻鹬类迁徙路线上的重要迁徙停歇地.本文通过分析崇明东滩回收的异地环志鸻鹬类记录及异地回收的崇明东滩环志的鸻鹬类记录,研究崇明东滩鸻鹬类的迁徙路线.1979～2008年间,崇明东滩共回收到来自澳大利亚西北部、澳大利亚维多利亚、美国阿拉斯加及新西兰北岛等17个国家与地区环志的鸻鹬类265只,包括大滨鹬(Calidris tenuirostris)、斑尾塍鹬(Limosa lapponica)、红腹滨鹬(C.canutus)等16种鸟类,其中春季北迁期间的记录占总数的93%;2003～2008年间,澳大利亚西北部、新西兰南岛、中国大陆及新西兰北岛等10个国家与地区回收到崇明东滩环志的大滨鹬、斑尾塍鹬、红腹滨鹬等12种鸟类,共计164只.在所有与崇明东滩鸻鹬类存在迁徙连接的20个国家和地区中,澳大利亚西北部的回收记录占全部回收记录的55%.根据斑尾塍鹬和红腹滨鹬不同亚种的越冬地分布,崇明东滩回收的斑尾塍鹬有L.l.menzbieri与L.l.baueri两个亚种,红腹滨鹬有C.a.piersmai和C.a.rogersi两个亚种.     

麻雀身体大小的性二态和基于身体量度的性别判定

身体大小的性二态是鸟类中较为普遍的现象。性二态的研究是理解性选择的关键,也能为性二态鸟类的野外快速性别判定提供依据。麻雀Passer montanus通常被认为是一种性单态鸟类,野外很难通过外在特征识别性别,有关麻雀性二态和性别判定的研究很少。2017—2018年每年的1—3月,在甘肃省庆阳市陇东学院校园内用雾网捕捉到67只麻雀成鸟,并测量了这些麻雀的10个身体量度。通过观察生殖腺鉴定了性别,确定为31只雄鸟和36只雌鸟。结果发现,总体上麻雀身体量度存在显著的两性差异(MANOVA:Pillai's Trace=0.492,F_(10,56)=5.426,P0.001),雄鸟的全长、尾长、翅长、跗跖长和中趾长显著大于雌鸟(t-test:P0.05)。利用这5个身体量度变量构建判别方程来判定麻雀性别,发现:在所有的单变量判别方程中,翅长构建的判别方程具有最高的性别判定准确率,达77.6%;由5个身体量度变量构建的典型判别方程,性别判定准确率为82.1%;而由全长和翅长构建的逐步判别方程,性别判定准确率为79.1%。麻雀存在身体大小的性二态,而这使得野外通过测量身体量度构建判别方程能较容易、准确地判定麻雀的性别。     

新疆鸟类新纪录——尖尾滨鹬、长趾滨鹬

2009年8月25～29日,笔者在新疆奎屯市北部泉沟污水池(44°29′N, 84°55′E,海拔390 m)连续拍摄到2只尖尾滨鹬Calidris acuminata和1只长趾滨鹬Calidris subminuta.经过仔细观察和鉴定,均为新疆鸟类新纪录种.在新疆的五彩湾(吉木萨尔)、克拉玛依、英吉沙等地也有过长趾滨鹬记录.     

嘉陵江下游蛇鮈的两性异形与雌性个体生殖力

为了解蛇鮈雌雄间是否存在显著的外部形态差异及雌性个体生殖力情况, 在繁殖期对嘉陵江下游(合川江段)共76尾蛇鮈样本的两性异形、性比及雌性个体生殖力进行分析.结果表明: 嘉陵江下游蛇鮈繁殖群体的性比接近1∶1,且蛇鮈两性的体型大小相同,但局部特征(如头部和躯干部等)呈现出显著的两性异形,如成体雄性蛇鮈的头部、胸鳍和腹鳍均较雌性蛇鮈大,而躯干部的体宽、体高和躯干长则是雌性蛇鮈大于雄性蛇鮈,这可能是性选择长期作用的结果.主成分分析显示,前3个主成分的累积贡献率达75.2%,但雌雄个体间形态特征相互重叠,无法将两者截然分开;利用判别函数对蛇鮈性别进行回判,综合判别准确率为92.1%.蛇鮈雌性个体绝对生殖力在979～19979粒;且与体长和去内脏体质量均呈显著正相关.同历史资料相比,本研究中嘉陵江蛇鮈的生殖力增大显著,这可能是蛇鮈对种群资源量下降和水环境变化主动适应的结果.     

形目15种鸟类线粒体ND6基因序列差异及其系统进化关系

采用PCR和质粒克隆测序方法 ,首次获得形目 15种鸟类线粒体基因组的ND6基因全长 5 2 2bp的序列。经对位排列 ,序列间未见有插入和缺失 ,共有 2 16个变异位点 ,种间序列差异为 5 17%～ 19 92 %。以白鹳为外群 ,用NJ法构建 15种鸟类的进化关系树。研究结果表明 :构建的系统树将形目 15种鸟类分为 2个支系。第 1支系包括蒙古沙、环颈、灰斑和反嘴鹬。第 2支系包括红脚鹬、林鹬、青脚鹬、翘嘴鹬、翻石鹬、大滨鹬、尖尾滨鹬、斑尾塍鹬、中杓鹬、大杓鹬和白腰杓鹬 ,其中鹬属的 3个种和杓鹬属的 3个种分别组成一个单系 ;翘嘴鹬和翻石鹬、大滨鹬和尖尾滨鹬分别聚为姊妹群 ,表现出较近的亲缘关系 ;斑尾塍鹬独立分支出来。分子证据提示 :鹬科中的塍鹬属、科中的斑属应提升为亚科分类阶元 ;反嘴鹬与科鸟类亲缘关系较近 ,组成一个单系 ,将其归入科下属的一个类群更为合理 ,与核型研究结果及Sibley新分类体系的观点相一致 [动物学报 49(1) :6 1～ 6 7,2 0 0 3]。     

4种水鸟途经北京的新记录

自 1 987年《北京鸟类志》出版以来 ,陆续又有一些北京地区鸟类的新分布记录。 2 0 0 3～ 2 0 0 4年 ,我们在开展“北京地区生物多样性现状与可持续发展规划方案研究”项目研究时又发现了 4种北京地区尚未记述过的鸟类。现报道如下。1 .阔嘴鹬 (Limicolafalcinellus)2 0 0 3年 9月 1 8日约 1 5 :0 0时 ,在北京市延庆野鸭湖湿地自然保护区记录到 1只亚成体水鸟。该鸟体型似滨鹬类 ,但喙基宽阔 ,喙长而尖端下弯 ;羽色似沙锥 ,具白色眉纹和黑色过眼纹。经照片鉴定 ,该鸟为阔嘴鹬的亚成体。阔嘴鹬繁殖于欧亚大陆北部 ,越冬于地中海、红海、印度…     

四眼斑水龟个体大小和体形的两性异形

研究龟鳖的两性异形对理解形态适应具有重要意义。通过测量41只(21♀,20♂)成体四眼斑水龟(Sacalia quadriocellata)的20个形态特征指标,研究四眼斑水龟个体大小和体形的两性异形。结果表明:除头长、头宽、尾长和尾长肛前段长外,四眼斑水龟其他的形态特征均与背甲长呈正相关。雌性的背甲长、腹甲长、腹甲中线长、腹甲曲线长显著大于雄性;雄性的头长、头宽、后肢长、尾长和尾长肛前段长显著大于雌性;雌雄两性的体重、体周长、前肢长、腹甲宽、肛盾切口长、肛盾切口宽以及除背甲长外的所有背甲形态特征指标均无显著差异。研究结果表明,四眼斑水龟存在个体大小和体形两性异形。     

棒花鱼形态特征的两性异形和雌性个体生育力

测定了棒花鱼(Abbottina rivularis)繁殖期形态特征包括体长、头长、头宽、头高、眼间距、鼻间距、背鳍基长、胸鳍长、胸鳍腹鳍间距、尾柄长、尾鳍长和体重的两性异形和雌性个体生育力。结果表明,雄性个体的数量显著多于雌性个体,雄性个体的体长显著大于雌性个体。特定体长的雌性个体的胸鳍腹鳍间距显著大于雄性个体,头长、头宽、头高、眼间距、鼻间距、背鳍基长、胸鳍长、尾柄长和尾鳍长显著小于雄性个体,雌雄两性体重不存在显著差异。棒花鱼的怀卵数量与体长和体重回归关系显著。偏相关分析显示,当控制第三者恒定时,怀卵数量与体长和体重呈正相关但不显著。棒花鱼存在个体大小和其他局部特征显著的两性异形,雌性个体主要通过腹腔容积的增加提高个体生育力。棒花鱼形态特征的两性异形是性选择和生育力选择共同作用的结果。     

四川省鸟类新记录——大滨鹬

正2020年9月20日,笔者在四川省宜宾市翠屏区菜坝镇鱼尾坝进行鸟类调查时,发现数量较多的鸻鹬类,当日13∶00,1只体型比旁边的红脚鹬Tringa totanus更小、比黑腹滨鹬Calidris alpina更大的鸟,停落到正在觅食的三趾滨鹬Calidris alba旁,三趾滨鹬奋力驱赶,因此,该鸟站立几秒钟即飞离,由于距离较近,拍摄到照片(图1)。该鸟体羽灰褐色,上体色深并具模糊纵纹,头顶纵纹明显,胸部和两侧具黑色点斑,喙黑色。     

鲶鱼和胡子鲶的两性异形与雌性个体生育力

检测了鲶鱼(Silurus asotus)和胡子鲶(Clarias fuscus)繁殖期18个形态特征的两性异形以及雌性个体生育力。结果表明,鲶鱼和胡子鲶雌雄性别比例均符合1∶1。One-way ANOVA显示,鲶鱼雌雄个体体长差异不显著,胡子鲶雌性个体体长显著小于雄性个体(P0.05)。以体长为协变量的One-way ANCOVA显示,特定体长的鲶鱼雌性个体的眼间距和体高显著大于雄性个体(P0.05),两性间其它局部特征不存在显著的两性差异;特定体长的胡子鲶雌性个体的体高、腹鳍基前距和腹鳍臀鳍间距显著大于雄性个体,雌性个体的臀鳍基长、尾柄高和尾鳍长显著小于雄性个体(P0.05),两性间其它局部特征不存在显著的两性差异。Two-way ANOVA显示,胡子鲶体长显著大于鲶鱼(P0.05),性别及物种与性别两因素的相互作用对体长影响不显著。以体长为协变量的Two-way ANCOVA显示,胡子鲶的头长、头宽、吻长、眼间距、尾柄高、尾鳍长、背鳍基前距、背鳍基长、腹鳍基前距、腹鳍臀鳍间距、体重和去内脏体重显著大于鲶鱼,头高、体高、臀鳍基长显著小于鲶鱼(P0.05),物种间的其他形态特征变量差异不显著;雌性个体的体高、背鳍基前距、腹鳍基前距、腹鳍臀鳍间距显著大于雄性个体,臀鳍基长、尾柄高、尾鳍长、背鳍基长显著小于雄性个体(P0.05),两性间的其他形态特征变量差异不显著;物种与性别两因素的相互作用对体高、臀鳍基长、尾柄高、尾鳍长、背鳍基长和腹鳍臀鳍间距影响显著,对其余的形态特征变量影响不显著。15个形态特征变量的主成分分析(Eigenvalue≥1)发现,前2个主成分共解释68.4%的变异。头宽、眼间距、尾柄高、尾鳍长、背鳍基前距、背鳍基长、腹鳍基前距和腹鳍臀鳍间距在第一主成分有较高的正负载系数,臀鳍基长在第一主成分有较高的负负载系数(解释51.2%变异);眼后头长在第二主成分有较高的负负载系数(解释17.2%变异)。胡子鲶在第一主成分和第二主成分的分值均显著大于鲶鱼,雌雄两性的差异以及两因素的相互作用对分值的影响均不显著。实验检测的鲶鱼、胡子鲶的怀卵数量与体长和体重回归关系显著。One-way ANCOVA及矫正平均值Tukey's检验显示,特定体长的胡子鲶的产卵数量显著大于鲶鱼。性选择是胡子鲶大个体雄性形成的主要原因,同时影响与运动相关的尾部特征。生育力选择更多的影响与雌性胡子鲶较大腹腔容积相关的形态特征变异。环境因子、食物可得性和营养状况同时影响了个体大小两性异形的形成。     

Bill length: a reliable method for sexing Purple Sandpipers

ABSTRACT.   Purple Sandpipers ( Calidris maritima ) are sexually dimorphic, with females larger than males. We tested the reliability of using bill length to sex individuals and estimate the sex ratio at a stopover site in Iceland in May 2003 and 2005. Feather samples from 65 of 324 captured birds were used for molecular sexing, and generalized linear models (GLMs) were used to discriminate the sexes from body measurements of the molecularly sexed birds. About 3% of the 324 individuals were misclassified by the Harding-Cassie method, and the proportion of males was 0.657 compared to 0.656 according to the best GLM. Our results showed that the reliability of determining the sex and sex ratio of Purple Sandpipers using a Harding-Cassie plot of bill length measurements was high, but that reliability was improved by including other variables in a GLM. The estimate of an uneven sex ratio in the population we studied was not due to a systematic error, and supports the conclusion of earlier studies that Purple Sandpipers exhibit an uneven sex ratio in favor of males.     

Use of wetlands at the mouth of the Yangtze River by shorebirds during spring and fall migration

ABSTRACT.   The mouth of the Yangtze River is an important stopover site for migratory shorebirds using the East Asian-Australasian Flyway. From 1984 to 2004, we censused and banded shorebirds and monitored hunting activities at the mouth of the Yangtze River to understand how shorebirds used the study area. Counts and banding data revealed greater numbers of shorebirds at the mouth of the Yangtze River during northward migration (spring) than during southward migration (fall), with ratios varying from 1.5:1 to 7.2:1 at different sites from 1984 to 2005. The most common species observed during spring (northward) migration were Great Knots ( Calidris tenuirostris ), Red Knots ( Calidris canutus ), Bar-tailed Godwits ( Limosa lapponica ), Sharp-tailed Sandpipers ( Calidris acuminata ), and Red-necked Stints ( Calidris ruficollis ). During spring 2003–2004, 96.98% of the shorebirds observed were adults (ASY or older) and 3% were after hatching-year and second-year birds (AHY or SY). In contrast, almost all (94.73%) birds counted during the fall were hatching-year (HY) birds. These results indicate that adult shorebirds either use a different migration route during fall migration or use the same route, but do not stop at the mouth of the Yangtze River. HY birds, however, may depend on the coastal stopover sites for feeding during their first southward passage.     

Sexual size dimorphism and sex identification using morphological traits of two Aegithalidae species

The black-throated tit, Aegithalos concinnus, and long-tailed tit, A. caudatus, are two widely-distributed species of Aegithalidae. They are thought to be monomorphic and thus difficult to differentiate between sexes in the field. We determined the sex of 296 black-throated tits and 129 long-tailed tits using DNA analysis, evaluated their sexual size dimorphism, and developed discriminant models to identify sex based on morphometries, including bill length, bill depth, bill-head length, maximum tarsus length, tarsus width, wing length, tail length, total body length, and body mass. Both species were sexually dimorphic in size, with males having larger measurements than females, except for bill length in black-throated tits, and both bill length and body mass in long-tailed tits. Moreover, both species showed similar sexual size dimorphism (SSD) among the morphological features, with tail length having the highest SSD value. The multivariate discriminant models for sex identification had an accuracy of 82% for both species, which was slightly higher than the best univariate discriminatory model for each species. Because of the complicated nature of the multivariate model, we recommend univariate models for sex identification using D = 0.491 × tail length - 24.498 (accuracy 80%) for black-throated tits and D = 0.807 × wing length - 45.934 (accuracy 78%) for long-tailed tits. Females in both species showed generally higher morphological variation than did males, resulting in lower accuracies in all discriminate functions regardless of univariate or multivariate approach. This could be the result of a sex-biased selective pressure in which males have higher selective pressures for these morphological features.     

发冠卷尾性别判定的初步研究

摘要：发冠卷尾（Dicrurus hottentottus）由于被认为是雌雄同态而在野外难以鉴别性别。我们研究了河南董寨国家级自然保护区79只已用分子生物学方法鉴定出性别的发冠卷尾（D.h.brevirostris）在形态量度上的性别差异,并据此构建了判别式方程,用于鉴定其性别。所考察的体征包括体重、喙长、喙粗、头喙长...     

Sex determination of African Penguins Spheniscus demersus using bill measurements: method comparisons and implications for use

African Penguins Spheniscus demersus are sexually dimorphic; on average, males are larger than females but measurements overlap making sex determination difficult through observations alone. We developed a discriminant function, using bill length and depth from a sample of birds sexed from gonad visualisation during post-mortem, which correctly classified 93% of the individuals. Cross-validation correctly assigned 90% of DNA-sexed birds and 91% of birds sexed by partner measurement comparisons. The use of discriminant function score cutpoints, while leaving 16% and 29% of birds unclassified, improved accuracy of birds sexed by DNA to 97% and of those sexed by partner comparison to 99%. Bill depth was found to be a discriminating variable. However, two techniques for measuring bill depth are currently in use for African Penguins. While these measurements are correlated (r = 0.85), they differ on average by 1.4?mm hindering accuracy of sex determination when using a discriminant function developed from the other bill depth measurement. Exploration of adult bill morphology of birds sexed from DNA at different colonies suggests the discriminant functions can be applied throughout the African Penguins’ South African range.     

Latitudinal clines in sex ratio, bill, and wing length in Least Sandpipers

ABSTRACT.   Differential distribution of nonbreeding Least Sandpipers ( Calidris minutilla ) according to sex, bill, and wing length was documented using capture data from six locations between California and Ecuador. The distribution of age classes did not vary with latitude. Females, which are slightly larger than males, migrated further south. Wing length increased toward the south for both males and females, which is consistent with the notion that longer wings are adaptive for longer migrations. Bill length also increased in both sexes from north to south. A latitudinal cline in prey burying depth may underlie the clines in bill length as well as in sex ratio.     

ON THE SOUTH AFRICAN RACE OF THE LITTLE SPOTTED WOODPECKER

Discriminant analysis functions have previously been determined for sexing Mediterranean Yellow-legged Gulls Larus michahellis michahellis from the western Mediterranean basin. However, data from eastern Mediterranean populations are lacking. In this work, we used morphometric data from a sample of 81 Mediterranean Yellow-legged Gulls (39 males and 42 females) breeding in the Gulf of Gabès in south-eastern Tunisia to (1) determine a discriminant function useful for sex discrimination, and (2) assess the accuracy of previously published functions in sexing Mediterranean Yellow-legged Gulls from our study area. Our results showed marked sexual differences in all morphological measurements, with males being significantly larger than females. The best discriminant function included head length, bill depth and wing length, and accurately classified 93% of sampled birds. We also found that Mediterranean Yellow-legged Gulls from the Gulf of Gabès could accurately be sexed using discriminant functions determined for another North African population, but not with a function determined for a South European population, although distances between sites are almost the same.     

Sex determination of Antarctic Petrels Thalassoica antarctica by discriminant analysis of morphometric characters

We present data on sexual dimorphism in some morphological measurements (wing length, head length, bill depth and bill length) in the Antarctic Petrel Thalassoica antarctica. Males were on average larger than females for all measurements. Sexual dimorphism was on average largest for bill depths whereas wing lengths discriminated least between the sexes. A discriminant function including bill depth, head length and wing length correctly sexed 92% of the sample. Due to between-measurer variation it is recommended that morphometric measurements obtained by others on sexed birds are compared with ours before proceeding with the use of the discriminant function on unsexed individuals.Publication No. 116 of the Norwegian Antarctic Research Expeditions (1991/92)     

The Feeding of Nestling St. Kilda Wrens

Annual breeding productivity of Knots Calidris canutus was estimated by the proportion of first-year birds in winter ringing samples. Significant associations were found between the productivity of Knots, other species that are known to breed on the Taimyr Peninsula, and lemming abundance in that region. It is inferred from this that Knots wintering in southern Africa are of the Russian subspecies canutus unlike British wintering birds which do not show these correlations and are subspecies islandica.     

Sexing terns using biometrics: the advantage of within-pair comparisons

Capsule Within-pair comparisons substantially improve the accuracy of sexing from biometrics for two congeneric species of seabird with monomorphic plumage and soft-tissue colouration.

Aims To examine the extent to which statistical limitations of sexing birds from biometrics using sample-level analysis could be overcome by sexing Common and Arctic Terns (Sterna hirundo and S. paradisaea) using measurements obtained from breeding pairs.

Methods Incubating adults were caught at the nest using walk-in traps and wing, tarsus, head-plus-bill, tail length, tail fork, and body mass measured. Each bird was individually colour-ringed and dyed with picric acid, enabling subsequent sexing by behavioural observations of copulation and courtship feeding. Birds were sexed using biometrics and the proportion of birds sexed correctly this way at the sample level was compared with the accuracy achieved if, within a pair, the larger bird was classified as male.

Results Head-plus-bill length was the single most accurate measurement for sexing individuals of both species, and correctly classified 72% of Arctic Terns and 73% of Common Terns. Combinations of measurements derived from discriminant analysis achieved slightly higher accuracy (73% and 78% respectively). Within-pair comparisons were more accurate than sample-level analysis for both single measurements and discriminant functions, and were able to sex 84% of Arctic Terns and 86% of Common Terns correctly.

Conclusion Comparing birds within pairs improves accuracy and can eliminate the need to calculate cut points or discriminant functions from a sample of birds of known sex for each particular study. We strongly advocate such comparisons wherever possible to increase accuracy and simplify computational procedures for predicting sex, thus reducing associated sources of error.