小杜鹃对小鳞胸鹪鹛的巢寄生

鸟类的巢寄生现象一直被作为生物协同演化的典型模式系统之一。对杜鹃选择宿主及其巢寄生情况进行调查和观测,能够为协同演化研究提供重要基础资料。2015年7月,我们在四川省雷波县发现一个被杜鹃寄生的鸟巢。通过野外观测和分子生物学检测,确定宿主为小鳞胸鹪鹛(Pnoepyga pusilla),而寄生者为小杜鹃(Cuculus poliocephalus)。     

中杜鹃捕食比氏鹟莺的卵

许多杜鹃在产下寄生卵之前通常会先叼走或吃掉宿主的1~2枚卵,这说明杜鹃不仅是寄生性繁殖的鸟类,同时可能也是潜在的捕食者。关于杜鹃对其宿主巢捕食的动机,一般认为一是由于杜鹃发现宿主巢时,已不适合寄生,将其捕食或毁坏可迫使宿主重新筑巢,从而杜鹃会获得寄生机会;二则可能由于宿主识别并拒绝了寄生卵,一些杜鹃会通过捕食或破坏宿主的巢,作为对宿主的一种惩罚性报复。2015年6月,在贵州宽阔水自然保护区,通过录像首次记录到中杜鹃(Cuculus saturatus)捕食整巢比氏鹟莺(Seicercus latouchei)卵的行为,表明中杜鹃不仅是许多宿主鸟类的巢寄生者,同时也可能是其巢捕食者。     

大杜鹃对北红尾鸲的放牧行为

在宿主的寄生防御压力下,鸟类巢寄生者通常会进化出一系列有效的寄生行为以提高其自身的繁殖适合度。以往研究发现,部分巢寄生者可能具有类似人类的"放牧"行为,即通过破坏或捕食不适合寄生的宿主巢,促使其重新筑巢以获取新的寄生机会。然而,对于其野外行为事件的报道并不多见。2018年5至8月,在贵州六枝地区,通过对宿主北红尾鸲(Phoenicurusauroreus)的巢进行录像监控,首次记录到大杜鹃(Cuculus canorus)对正在孵卵的北红尾鸲的放牧行为。进一步查阅了大杜鹃寄生系统中已有的放牧案例,说明放牧行为很可能是大杜鹃普遍采用的一种寄生策略。     

三个东方大苇莺种群大杜鹃寄生率的变异

东方大苇莺Acrocephalus orientalis是大杜鹃Cuculus canorus的主要寄主之一。本文对东方大苇莺的3个地理种群进行杜鹃寄生率的时空比较。发现不同东方大苇莺种群被大杜鹃的巢寄生率在21.4%和65.5%之间,差异显著;不过,地理位置相近的两个种群在巢寄生率上则没有显著差异。另外,同一地理种群的巢寄生率年间也存在显著差异。     

小杜鹃在强脚树莺巢中寄生繁殖

2006年6~7月作者在贵州省宽阔水自然保护区首次发现小杜鹃(Cuculus poliocephalus)在强脚树莺(Cettiafortipes)巢中寄生(封4图片),并对这一现象进行了连续观察,对小杜鹃的雏鸟生长进行了测量。报道如下:宽阔水自然保护区位于贵州省遵义市绥阳县北部(28°06′25″~28°19′25″N     

云南楚雄发现绿孔雀繁殖巢

正绿孔雀(Pavo muticus)在我国主要分布于云南省中部、南部及西部地区,国内关于其在野生状态下的繁殖生物学资料较为缺乏,仅郑作新(1979)、杨岚等(1995)对绿孔雀的巢与卵等有简单描述记录,但迄今为止,中国境内尚无确切的野外绿孔雀巢的影像资料发表。2017年5月20日,在元江上游绿汁江流域的楚雄市双柏县(23°25′55″N,101°11′13″E,海拔1 132 m)境内进行样线调查时惊飞绿孔雀,从而发现1处绿孔雀繁殖巢(图1、2)。该巢简陋,无明显边界,几乎无巢材,仅     

甘肃莲花山红喉歌鸲繁殖巢记述

正红喉歌鸲(Luscinia calliope)在我国境内的东北和西部地区繁殖,目前繁殖资料报道仅限于《中国鸟类志·下卷·雀形目》(赵正阶2001)中的记述,该记述是基于长白山地区繁殖种群的观察,其他地区繁殖种群的繁殖资料尚未有公开报道。2011年和2012年两个年度我们在甘肃莲花山国家级自然保护区的沙河滩保护站各发现红喉歌鸲1巢,两个年度发现的巢几乎位于同一地点(34°55′56″N,103°44′16″E,海拔2 815 m)。     

北京小龙门东方中杜鹃多重寄生冕柳莺的报道

多重巢寄生是1只或多只寄生性鸟类在1个宿主巢内产2枚或多枚卵的特殊行为方式。对于雏鸟具有排他性的杜鹃而言,多重寄生被认为是种内个体之间或种间的一种竞争,但相关报道较少。通过野外观察和分子生物学检测技术,我们在北京小龙门国家森林公园确定了一个被东方中杜鹃(Cuculus optatus)多重寄生的冕柳莺(Phylloscopus coronatus)巢。     

中杜鹃在3种宿主巢中寄生繁殖

了解杜鹃对其宿主的选择和寄生情况,能为两者间的协同进化研究提供重要的基础资料。2012和2013年每年的4～8月,在贵州宽阔水国家级自然保护区对不同生境类型中的鸟巢进行搜索监测,记录到4例中杜鹃(Cuculus saturatus)寄生繁殖现象,其宿主分别是暗绿绣眼鸟(Zosterops japonicus)、棕腹柳莺(Phylloscopus subaffinis)和黄喉鹀(Emberiza elegans),其中棕腹柳莺和暗绿绣眼鸟是首次记录到被中杜鹃寄生。中杜鹃卵重(2.39±0.14)g(n=3),体积(2.24±0.18)cm3(n=3),通过T检验方法发现中杜鹃卵极显著大于暗绿绣眼鸟和棕腹柳莺卵(P0.001),同时在形状上也与两者极不相似,中杜鹃卵呈明显的长椭圆形,与黄喉鹀的卵在大小上无显著差异(P=0.1)。反射光谱的分析结果发现,寄生于不同宿主巢的中杜鹃卵在背景色和斑点上都具有一定差异,这表明中杜鹃的卵可能存在基因族群的分化。     

陕西长青发现棕腹杜鹃和八声杜鹃

正2014年7月16日和2015年6月9日,先后在陕西洋县长青国家级自然保护区内(33°38′42.25″N,107°29′54.42″E,海拔1 199~1 319 m)分别发现并拍摄到两种杜鹃科鸟类。参考相关文献(约翰·马敬能等2000,赵正阶2001,Erritz?e et al.2012),鉴定为棕腹杜鹃(Cuculus nisicolor)和八声杜鹃(Cacomantis merulinus)(图1)。两种杜鹃均为陕西省首次记录(郑光美2011)。棕腹杜鹃为亚成鸟,生境为靠近溪流的落叶阔叶林,林下为巴山木竹林(Arundinaria fargesii)。其头顶、颈     

A new species of parasitic mites of the genus Syringophiloidus Kethley 1970 (Acari: Syringophilidae) from the barn swallow Hirundo rustica Linnaeus, 1758

A new quill mite species Syringophiloidus hirundinis (Acari: Syringophilidae) is described from the Barn Swallow Hirundo rustica. The species Syringophiloidus hirundinis had a prevalence of 17.1% in the two outermost tail feathers (N = 208 adult Barn Swallows) during the breeding season of the Barn Swallow host. Intensity of infestation was 9.7 adult mites per pair of infested tail feathers. The sex ratio was highly biased towards females, with only 7.5% of all individuals being males (20:3).     

EFFECTS OF A HAEMATOPHAGOUS MITE ON THE BARN SWALLOW (HIRUNDO RUSTICA): A TEST OF THE HAMILTON AND ZUK HYPOTHESIS

I tested three assumptions of the Hamilton and Zuk hypothesis (1982), which suggests that the extravagant male plumage of many bird species allows females to choose mates that are resistant to the parasites exploiting the host population at a given time. By choosing such males as mates, females will rear offspring carrying the genes for resistance. I tested three necessary conditions for the Hamilton and Zuk model: (1) whether parasites affect the fitness of their hosts; (2) whether there is heritable variation in parasite resistance, and (3) whether the expression of the sexual ornament varies with parasite burden. The haematophagous mite Ornithonyssus bursa (Macronyssidae, Gamasida) sucks blood from their Barn Swallow (Hirundo rustica) hosts. Experimental manipulation of mite loads and partial cross-fostering experiments on Barn Swallows, where half of the nestlings in the brood were exchanged with nestlings from another nest, shows that parasite burdens and origin, but not rearing conditions, of Bam Swallow nestlings, affected their adult tarsus length and maximum body weight shortly before fledging. Mite loads of adult Barn Swallows at spring arrival were more similar to mite loads of their own offspring, whether reared in their own or in foster nests inoculated with mites, than to loads of foster offspring. Parent Barn Swallows with long tail ornaments had offspring with smaller mite loads in the partial cross-fostering experiments. The amount of increase in male tail ornaments from one year to another was negatively related to experimentally manipulated mite loads of Barn Swallow nests during the preceding breeding season. In conclusion, the three assumptions of the hypothesis were supported by the experimental tests.     

Host density predicts presence of cuckoo parasitism in reed warblers

In some hosts of avian brood parasites, several populations apparently escape parasitism, while others are parasitized. Many migratory specialist brood parasites like common cuckoos, Cuculus canorus , experience a short breeding season, and in order to maintain local parasite populations host densities should be sufficiently high to allow efficient nest search. However, no studies have investigated the possible effect of host density on presence of cuckoo parasitism among populations of a single host species. Here, we investigated possible predictors of common cuckoo parasitism in 16 populations of reed warblers, Acrocephalus scirpaceus , across Europe. In more detail, we quantified the effect of host density, number of host breeding pairs, habitat type, mean distance to nearest cuckoo vantage point, predation rate and latitude on the presence of cuckoo parasitism while controlling for geographical distance among study populations. Host density was a powerful predictor of parasitism. We also found a less pronounced effect of habitat type on occurrence of parasitism, while the other variables did not explain why cuckoos utilize some reed warbler populations and not others. This is the first study focusing on patterns of common cuckoo-host interactions within a specific host species on a large geographic scale. The results indicate that if host density is below a specific threshold, cuckoo parasitism is absent regardless of the state of other potentially confounding variables.     

Hawk mimicry in cuckoos and anti‐parasitic aggressive behavior of barn swallows in Denmark and China

Hosts of brood parasites defend their nests against parasitism by aggression and subsequently, if parasitized, by rejection of the parasite egg or nestling. Cuckoos have evolved plumage mimicry with convergence towards the phenotype of Accipiter hawks that are common predators of cuckoo hosts. Here we tested two alternative hypotheses 1) whether barn swallows Hirundo rustica have evolved less aggressive behavior towards cuckoos in areas of sympatry with more abundant Accipiter hawks; and 2) whether barn swallows have evolved more aggressive anti‐parasite behavior in areas with a single species of cuckoo. We presented dummies of common cuckoo Cuculus canorus, sparrowhawk Accipiter nisus and Oriental turtledove Streptopelia orientalis (a benign control) at the nests of barn swallows during breeding, while recording intensity of response and proximity of barn swallows to the dummy. We demonstrated that cuckoos moved away when attacked aggressively and approached more closely by barn swallows showing that barn swallow behavior was efficient at driving away cuckoos. Barn swallows were significantly more aggressive and approached cuckoo and sparrowhawk dummies more closely in Denmark than in China, despite sparrowhawks being relatively more common in Denmark. Responses towards cuckoo dummies differed from responses towards sparrowhawk dummies, showing that barn swallows distinguished between the two different causes of danger. These findings are inconsistent with a less aggressive response towards cuckoo dummies in areas of sympatry with more abundant Accipiter hawks, but consistent with the alternative hypothesis that barn swallows have evolved more aggressive behavior towards cuckoos in areas with a single species of brood parasite, but not in areas with multiple species of parasites, where it is harder for hosts to tell the difference.     

Integrating stable isotopes,parasite, and ring‐reencounter data to quantify migratory connectivity—A case study with Barn Swallows breeding in Switzerland,Germany, Sweden,and Finland

Ecosystems around the world are connected by seasonal migration. The migrant animals themselves are influenced by migratory connectivity through effects on the individual and the population level. Measuring migratory connectivity is notoriously difficult due to the simple requirement of data conveying information about the nonbreeding distribution of many individuals from several breeding populations. Explicit integration of data derived from different methods increases the precision and the reliability of parameter estimates. We combine ring‐reencounter, stable isotope, and blood parasite data of Barn Swallows Hirundo rustica in a single integrated model to estimate migratory connectivity for three large scale breeding populations across a latitudinal gradient from Central Europe to Scandinavia. To this end, we integrated a non‐Markovian multistate mark‐recovery model for the ring‐reencounter data with normal and binomial mixture models for the stable isotope and parasite data. The integration of different data sources within a mark‐recapture modeling framework enables the most precise quantification of migratory connectivity on the given broad spatial scale. The results show that northern‐breeding populations and Southern Africa as well as southern‐breeding populations and Western–Central Africa are more strongly connected through Barn Swallow migration than central European breeding populations with any of the African wintering areas. The nonbreeding distribution of Barn Swallows from central European breeding populations seems to be a mixture of those populations breeding further north and south, indicating a migratory divide.     

Evolution of tolerance by magpies to brood parasitism by great spotted cuckoos

Hosts may use two different strategies to ameliorate negative effects of a given parasite burden: resistance or tolerance. Although both resistance and tolerance of parasitism should evolve as a consequence of selection pressures owing to parasitism, the study of evolutionary patterns of tolerance has traditionally been neglected by animal biologists. Here, we explore geographical covariation between tolerance of magpies (Pica pica) and brood parasitism by the great spotted cuckoo (Clamator glandarius) in nine different sympatric populations. We estimated tolerance as the slope of the regression of number of magpie fledglings (i.e. host fitness) on number of cuckoo eggs laid in non-depredated nests (which broadly equals parasite burden). We also estimated prevalence of parasitism and level of host resistance (i.e. rejection rates of mimetic model eggs) in these nine populations. In accordance with the hypothetical role of tolerance in the coevolutionary process between magpies and cuckoos we found geographical variation in tolerance estimates that positively covaried with prevalence of parasitism. Levels of resistance and tolerance were not associated, possibly suggesting the lack of a trade-off between the two kinds of defences against great spotted cuckoo parasitism for magpies. We discuss the results in the framework of a mosaic of coevolutionary interactions along the geographical distribution of magpies and great spotted cuckoos for which we found evidence that tolerance plays a major role.     

家燕和金腰燕的卵胚胎心率比较

胚胎心率是衡量胚胎新陈代谢速率的重要指标。鸟类的胚胎心率随新陈代谢的增加而呈上升趋势。对早成性鸟类的种间比较发现,胚胎心率平均值随卵重量的增大而减小,卵体积小的种类具有相对较高的胚胎心率。国内有关野生鸟类胚胎心率的研究较少。2014年5~8月,在黑龙江扎龙国家级自然保护区,利用红外胚胎心率测量仪对两种近缘鸟类家燕(Hirundo rustica,n=14)和金腰燕(Cecropis daurica,n=14)的卵胚胎心率及其变化进行了测量与比较。两种燕均在孵卵的第2天开始出现胚胎心率,并随胚龄增加心率呈上升趋势,但在第8天及第11~14天家燕的胚胎心率显著低于金腰燕(第8天:z=﹣2.602,P=0.009;第11天:z=﹣2.497,P=0.013;第12天:z=﹣2.354,P=0.019;第13天:z=3.424,P=0.001;第14天:z=﹣3.380,P=0.001)。家燕卵胚胎日均增长心率(19.0±3.1)次/min,金腰燕卵胚胎日均增长心率(16.1±3.4)次/min,二者差异不显著(z=﹣1.792,P=0.073)。两种燕的胚胎心率与卵容量和卵重均不存在显著相关性[家燕:卵容量(1.73±0.09)cm3,r=0.192,P=0.511;卵重(1.74±0.09)g,r=0.128,P=0.663。金腰燕:卵容量(1.74±0.08)cm3,r=0.040,P=0.891;卵重(1.51±0.09)g,r=0.054,P=0.855]。这可能表明,卵大小和卵重量对家燕与金腰燕的胚胎心率均影响不明显。     

Egg color variation,but not egg rejection behavior,changes in a cuckoo host breeding in the absence of brood parasitism

Interactions between parasitic cuckoos and their songbird hosts form a classical reciprocal “arms race,” and are an excellent model for understanding the process of coevolution. Changes in host egg coloration via the evolution of interclutch variation in egg color or intraclutch consistency in egg color are hypothesized counter adaptations that facilitate egg recognition and thus limit brood parasitism. Whether these antiparasitism strategies are maintained when the selective pressure of parasitism is relaxed remains debated. However, introduced species provide unique opportunities for testing the direction and extent of natural selection on phenotypic trait maintenance and variation. Here, we investigated egg rejection behavior and egg color polymorphism in the red‐billed leiothrix (Leiothrix lutea), a common cuckoo (Cuculus canorus) host, in a population introduced to Hawaii 100 years ago (breeding without cuckoos) and a native population in China (breeding with cuckoos). We found that egg rejection ability was equally strong in both the native and the introduced populations, but levels of interclutch variation and intraclutch consistency in egg color in the native population were higher than in the introduced population. This suggests that egg rejection behavior in hosts can be maintained in the absence of brood parasitism and that egg appearance is maintained by natural selection as a counter adaptation to brood parasitism. This study provides rare evidence that host antiparasitism strategies can change under parasite‐relaxed conditions and reduced selection pressure.     

Diet of nestling Barn Swallows <Emphasis Type="Italic">Hirundo rustica</Emphasis> in rural areas of Poland

Analysis of faecal sacs of nestling Barn Swallows Hirundo rustica from 52 breeding colonies located within fifteen spatially-separated villages in Poland has revealed that the basic component of the diet was Coleoptera (56.1% of all identified prey items), followed by Hymenoptera (24.1%), Diptera (16.1%) and Hemiptera (3.3%). The average mass of all prey items with known weight amounted to 3.40 mg (95% CL, 3.16–3.63 mg; median=0.49 mg) dry weight. Coleopterans associated with dung and manure jointly made up 23.5% of the number and 24.3% of the total biomass of all representatives of the order. Statistically significant negative relationships between the average weight of prey and number of prey found in 52 analyzed breeding sites suggest a particular need for Barn Swallows to find larger-bodied prey rather than to exploit the local abundance of smaller prey. The high percentage of Coleoptera in the diet of nestling Barn Swallows probably results from extensive or traditional farm management based on rules of organic farming in agricultural areas of central Europe, mainly commonly used organic fertilizers, and suggests the importance of these insects as a more easily accessible and larger-bodied prey in comparison to some small Diptera or Hymenoptera. We believe that a large number of randomly collected faecal samples from tens of breeding sites allow us to precisely describe variation in the diet of the Barn Swallow. Our work has great importance for documenting of the food composition of the Barn Swallow in traditional European countrysides, i.e. under environmental and agricultural conditions which, as a result of transformations of the system of farming, ceased to exist in the western and northern part of this continent.     

Use of field margins managed under an agri-environment scheme by foraging Barn Swallows Hirundo rustica

Capsule: Barn Swallows Hirundo rustica were more likely to forage along arable field margins that were enhanced with wildflowers or legumes than control grass margins.

Aims: To determine if foraging Barn Swallows displayed preferences for specific arable field boundary habitats (grass margins versus floristically enhanced margins) that were managed as part of an agri-environment scheme. We also aim to determine how Barn Swallow food abundance related to these habitats.

Methods: Two foraging activity surveys took place on all grass and floristically enhanced margins (n?=?56) present within the 600 m foraging range of seven Barn Swallow colonies during June and July 2016. Margin habitat use was measured by recording the presence/absence of foraging individuals during surveys, the total number of individuals and by calculating an index of foraging activity. Habitat information relating to adjacent boundary type, transect crop type and neighbouring crop type were also recorded.

Results: Foraging Barn Swallows were significantly more likely to be recorded when survey transects included a floristically enhanced margin, but there was no significant impact of floristically enhanced margins on the total number of individuals recorded or on the index of foraging activity. Foraging activity was higher along grass verges and hedgerows when compared to treelines and was positively related to length weighted Diptera abundance (a measure of food biomass).

Conclusion: Our results suggest that there may be a role for floristically enhanced margins in the conservation of Barn Swallows on arable farmland. More research, however, is needed to determine whether invertebrate-rich agri-environment scheme habitats can influence colony size or improve the breeding success of this species.