Non-breeding movements of the Black-tailed Gull(Larus crassirostris)

With the continued development of tracking technology and increasing interest in animal movement,our understanding of migration behavior has become more comprehensive.However,there are still many species that have not been well studied,particularly sea birds.Here,we present the first year-round Global Positioning System(GPS)tracking data of the Black-tailed Gull(Larus crassirostris)at the population level.We used solar-powered GPS-Global System for Mobile communication(GSM)loggers to successfully track 30 individuals breeding at Xingrentuo Islet,Liaoning Province,China,for 1-3 years.Except for one individual who roamed in the far north of the Yellow Sea during non-breeding period,all others did a directed southward migration.Migration routes and wintering sites differed among migrating gulls and between years for the birds tracked for two or more years.Additionally,during wintering,the migrating gulls were more likely to travel over a large body of water and shift sites,and some trajectories were quite complex,which was probably closely related to what we observed in the field about their boat-chasing behavior.Compared to wintering movements,the post-breeding movements ranged over a smaller area.Specifically,almost all of them had a long post-breeding period near the breeding islet(≥120days,<220 km from the breeding islet),and 80%of the gulls who were tracked more than one year had at least one faithful post-breeding site.Compared to the post-breeding period,only approximately half of the migrating gulls had a pre-breeding period that was shorter(3-20 days)and closer to the breeding islet(≤80 km).Migration distance varied among migrating gulls(range 209-2405 km)and the gulls moved least distance during postbreeding period.Furthermore,we found that the southward movement of the migrating gulls occurred when the temperature near the breeding islet dropped;specifically,the gulls directly migrated southward away from the post-breeding site.Our results suggest that the Black-tailed Gull has a long post-breeding period but a short prebreeding period near the breeding islet and high diversity of their migrating patterns(in especial migration routes and wintering sites).

Distribution and Status of the Pallas’s Gull Ichthyaetus ichthyaetus(Pallas,1773)in the Reservoirs of the Palearctic:Review

The Pallas’s Gull Ichthyaetus ichthyaetus is a piscivorous gull,some local populations of which are rare and vulnerable.The review presents data on the status and distribution of the Pallas’s Gull in the reservoirs of the Palearctic-water bodies in which the water level is controlled by humans.The aim of the study was to assess the current state of the species in the reservoirs of the Palearctic.The review was based on 1080 publications found in the search engines Yandex,Google,Google Scholar,eLybrary.During the last 35 years,the Pallas’s Gull has been found in 63 reservoirs of the Palearctic.Breeding has been established in 11 reservoirs,breeding has not been established in 43 reservoirs,and birds were present in 9 reservoirs,but the status was not specified.Two-thirds of the reservoirs where the gull was recorded or bred were located in the European part and only 1/3 in Asia.It is assumed that up to 5000 adults(0.45%-4.0%of the global population of the species)breed annually in the reservoirs of the Palearctic,and the reservoirs are not the main habitats for maintaining and reproducing the population of the species.The majority of the breeding population reproduces in natural water bodies,and the reservoirs of the Palearctic are important for the maintenance of non-breeding individuals.Detection of presumed breeding and new breeding colonies in reservoirs north of the historical range of the species has been established on the Russian Plain,in the Urals and Trans-Urals.The reservoirs of Russia play a leading role in providing breeding sites for the species in water bodies of this type.An analysis of the data allows us to state the important and increased role of reservoirs in the modern distribution and expansion of the range of the Pallas’s Gull in the Palearctic.

Investigation of Unsteady Aerodynamic Characteristics of a Seagull Wing in Level Flight

Unsteady aerodynamic characteristics of a seagull wing in level flight are investigated using a boundary element method.A new no-penetration boundary condition is imposed on the surface of the wing by considering its deformation.The geometry and kinematics of the seagull wing are reproduced using the functions and data in the previously published literature.The proposed method is validated by comparing the computed results with the published data in the literature.The unsteady aerodynamics characteristics of the seagull wing are investigated by changing flapping frequency and advance ratio.It is found that the peak values of aerodynamic coefficients increase with the flapping frequency.The thrust and drag generations are complicated functions of frequency and wing stroke motions.The lift is inversely proportional to the advance ratio.The effects of several flapping modes on the lift and induced drag(or thrust)generation are also investigated.Among three single modes(flapping, folding and lead & lag),flapping generates the largest lift and can produce thrust alone.For three combined modes,both flapping/folding and flapping/lead & lag can produce lift and thrust larger than the flapping-alone mode can.Folding is shown to increase thrust when combined with flapping,whereas lead & lag has an effect of increasing the lift when also combined with flapping.When three modes are combined together,the bird can obtain the largest lift among the investigated modes.Even though the proposed method is limited to the inviscid flow assumption,it is believed that this method can be used to the design of flapping micro aerial vehicle.

Seasonal changes in the number of Relict Gull (Larus relictus) at Ebinur Lake, Western China

The Relict Gull(Larus relictus) is recognized as a vulnerable species,with a worldwide population of about 6,000 individuals.Always inhabiting the extreme arid regions of Central Asia,their migratory routes and winter grounds are unclear.This research focused on distribution sites,habitat,behavior,population size and seasonal changes of Relict Gull.Line transects and point counts in every month were used to investigate the gulls around the Ebinur Lake.The result showed Relict Gull was summer visitor to Xinjiang,Western China.Population curve with a single peak was obtained.This gull appeared in early April and was 63 individuals(1% of the global population).The number remained stable from May to July in 2009.The discovery of fledglings indi-cates that Relict Gull may breed here.They left Ebinur Lake in August.Relict Gull in Ebinur Lake should belong to the Central Asian subpopulation,which was the most westerly record in China.

Migratory Behavior of Franklin’s Gulls (Larus pipixcan) in Peru

Information on the migratory pathways for birds is essential to the future citing of wind power facilities, particularly in off-shore waters. Yet, relatively little is known about the coastal or offshore migratory behavior of most birds, including Franklin’s gulls (Larus pipixcan), a long-distant migrant. We report observations along the coast of Peru made in November 2008 to determine where birds concentrated. Wind facilities can not avoid regions of high avian activity without knowing where that activity occurs. Migrant flocks of 250 to 50,000 were observed on coastal farmfields, dumps and estuaries, on beaches and mudflats, and up to 45 km offshore. Bathing and foraging flocks ranged in size from 20 to 500 birds, and most flocks were monospecific, with occasional grey-headed (Larus cirrocephalus) and band-tailed (L. belcheri) on the periphery. While previous notes report Franklin’s gulls foraging coastally, we found flocks feeding up to 45 km offshore by diving for prey or feeding on the water. The relative percentage of birds of the year varied in migrant flocks from zero to 14%, with lower numbers of young foraging aerially on insects (only 1%). The percentage of young feeding over the ocean decreased with increasing distance from shore;no young of the year were recorded at 36-44 km offshore. While there were large flocks of Franklin’s gulls resting on the water inshore, the number of gulls foraging offshore did not decline up to 45 km offshore. The presence of foraging flocks of Franklin’s gulls out to 45 km offshore, and occupying space from 0 to 20 m above the water, suggests that they would be vulnerable to offshore anthropogenic activities, such as offshore drilling and wind facilities.

Nest site tenacity and mate fidelity in the Black-headed Gull(Chroicocephalus ridibundus)

Breeding philopatry is well known in the Black-headed Gull(Chroicocephalus ridibundus).Using a capture-markrecapture method,we studied if Black-headed Gulls show nest site tenacity and mate fidelity as well,and investigated if there are differences between a stable,and a newly established and fast-growing colony,as well as for differences between the center and edges of these colonies located in north-eastern Germany.We found a high level of nest site tenacity in the center of the stable colony on B?hmke Island,and lower degrees of nest site tenacity at the edge of the same colony and in the newly established and fast-growing colony on Riether Werder.Mate fidelity was very strong in all individuals which returned to their previous breeding place,regardless of the nest site location.

红嘴鸥和喜鹊的粪便微生物群多样性比较研究

为评估不同种鸟类的病原体传播风险,提取红嘴鸥和喜鹊粪便的总DNA,通过PCR扩增16S rRNA序列V3~V4高变区,基于高通量测序和生物信息学研究两者肠道微生物群差异。研究结果显示,红嘴鸥和喜鹊粪便微生物群组成存在显著差异,两者粪便中最丰富的细菌门分别是厚壁菌门和变形菌门,前者粪便中绝对优势属是Catellicoccus(丰度均值65.5%)。红嘴鸥样本中均检测出弯曲杆菌属,检出率100%,丰度均值1.2%;喜鹊样本检出率55.6%,丰度均值0.019%。这表明,青岛市红嘴鸥种群广泛存在弯曲杆菌属,红嘴鸥的接触安全风险高于喜鹊。

Perinatal variation and covariation of oxidative status and telomere length in yellow-legged gull chicks

The perinatal period is critical to survival and performance of many organisms.In birds,rapid postnatal growth and sudden exposure to aerial oxygen around hatching markedly affect the chick redox status,with potentially negative consequences on physiology mediated by oxidative stress.In addition,telomere length(TL)undergoes reduction during birds’early life,partly depending on oxidative status.However,relatively few studies have focused specifically on the changes in oxidative status and TL that occur immediately after hatching.In this study of the yellow-legged gull Larus michahellis,we found that chicks undergo a marked increase in plasma total antioxidant capacity and a marked decrease in the concentration of pro-oxidant molecules during the first days after hatching.In addition,TL in erythrocytes decreased by 1 standard deviation over the 4days post-hatching.Body mass and tarsus length covaried with total antioxidant capacity and concentration of pro-oxidants in a complex way,that partly depended on sex and laying order,suggesting that oxidative status can affect growth.Moreover,TL positively covaried with the concentration of pro-oxidant molecules,possibly because retention of high concentrations of pro-oxidant molecules results from mechanisms of prevention of their negative effects,including reduction in TL.Thus,this study shows that chicks undergo marked variation in oxidative status,which predicts growth and subsequent TL,prompting for more studies of the perinatal changes in the critical posthatching stages.

Nest sanitation behavior does not increase the likelihood of parasitic egg rejection in herring gulls

Birds’behavioral response to brood parasitism can be influenced not only by evolution but also by context and individual experience.This could include nest sanitation,in which birds remove debris from their nests.Ultimately,nest sanitation behavior might be an evolutionary precursor to the rejection of parasitic eggs.Proximately,the context or experience of performing nest sanitation behavior might increase the detection or prime the removal of parasitic eggs,but evidence to date is limited.We tested incubation-stage nests of herring gulls Larus argentatus to ask whether nest sanitation increased parasitic egg rejection.In an initial set of 160 single-object experiments,small,red,blocky objects were usually rejected(18 of 20 nests),whereas life-sized,3D-printed herring gull eggs were not rejected whether red(0 of 20)or the olive-tan base color of herring gull eggs(0 of 20).Next,we simultaneously presented a red,3D-printed gull egg and a small,red block.These nests exhibited frequent nest sanitation(small,red block removed at 40 of 48 nests),but egg rejection remained uncommon(5 of those 40)and not significantly different from control nests(5 of 49)which received the parasitic egg but not the priming object.Thus,performance of nest sanitation did not shape individuals’responses to parasitism.Interestingly,parents were more likely to reject the parasitic egg when they were present as we approached the nest to add the experimental objects.Depending on the underlying mechanism,this could also be a case of experience creating variation in responses to parasitism.

Mismatching between nest volume and clutch volume reduces egg survival and fledgling success in black-tailed gulls

A longstanding suggestion posits that parents prefer to match nest volume and clutch size （clutch volume）, but few studies have tested this in colonial seabirds that nest in the open. Here, we demonstrate the effects of nest-clutch volume matching on egg survival, hatching, and fledgling success in black-tailed gulls Larus crassirostris on Hongdo Island, Korea. We show that the volume mismatch, defined as the difference between nest volume and total egg volume （the sum of all eggs＇ volume in the clutch）, was positively related to egg and chick mortality caused by predation, but was not significantly related to hatching success incurred by insulation during the incubation period. Although nest volume was negatively related to laying date, we found that the mismatch was positively related to laying date. Our results support the claim that well-matched nest-clutch volume may contribute to survival of eggs and chicks, and ultimately breeding success.

谈杜甫《旅夜书怀》之“独”而不得自由

《旅夜书怀》一诗,以愁情选悲景,以悲景写悲情。从诗歌所涉的时空层面来看,“悲”的内核在于“独”。“独”既是诗人思考的背景,也是诗人当时生命状态的总结。在这一富有情感浓度的环境中,诗人思绪万千,感眼前之无望,念人生之坎坷,由“独”而陷入了对人生困境的沉思。诗人因万事潦倒、信念崩塌而痛苦愁闷,又因“破”而难以接受、无法释怀、矛盾挣扎。尾联中沙鸥意象的运用,是诗人试图为摆脱困境探寻出路,但心有重负又何谈自由洒脱。沙鸥孤独却自由,诗人孤身却迷茫无措,踟蹰不前。这一意象的观照,赋予了“独”更为深刻的内涵:不仅是人生状态,也是人生归宿。

晚明王士性的“游道”思想及其在白鸥庄营造中的表达

晚明时期的旅游活动极为兴盛,许多文人发展出了自己的“游道”思想并渗透到当时的园林营造中。其中地理学家王士性的游道思想与造园艺术的结合尤为独特。本文通过文献资料对白鸥庄进行了复原,分析其营造内容,总结其“集锦式”园林的空间特征与内涵,挖掘其造园手法与王士性独特旅游经历及观念的关联。

归苓片血清药物化学研究(1)

目的:分析鉴定归苓片体内吸收入血化学成分。方法:建立归苓片以及大鼠口服归苓片含药血清的HPLC指纹图谱分析方法;分析归苓片全方/单味药及其大鼠含药血清指纹图谱,比对鉴定口服归苓片后大鼠血中成分、来源生药及其代谢产物。结果:从大鼠归苓片含药血清中显示出12个入血成分,其中7个为原型成分,5个为代谢产物。结论:血中成分及代谢产物可能为归苓片体内直接作用的药效成分,其分别来源于归苓片的组成药味。

黑嘴鸥巢址的时空变化

利用Arcview GIS对江苏盐城国家级自然保护区1999-2007年黑嘴鸥的巢址时空变化研究结果表明:区域尺度上,江苏盐城沿海黑嘴鸥种群数量维持在1000只左右,多年平均为954只±161.26只,但由于滩涂围垦和开发,其营巢地主要集中在核心区,种群数量占整个种群数量的85.24%±7.00%。地点尺度上,中路港巢区的多年平均面积为153.19hm2±112.09hm2,三里闸巢区的多年平均面积为62.60hm2±66.41hm2;两个巢区的质心总体上均向东南方向偏移,中路港巢区与潮沟大泗洋子距离以及三里闸巢区与潮沟大流水距离均呈现减小趋势;但同一巢区不同年份的重叠面积、密度和质心均不尽相同。影响黑嘴鸥巢区时空变化的因素包括年际间降雨量、潮水的入侵、植被演替等自然因素,同时还包括无序开发利用滩涂生物资源、拾捡鸟蛋、人为改变滩涂水动力等人为因素。鉴于此,提出了江苏盐城沿海黑嘴鸥及其栖息地的保护管理建议。

青海湖棕头鸥(Larus brunnicephalus)夏秋季活动区研究

2006年4-9月，采用无线电遥测技术对青海湖重要繁殖水鸟棕头鸥（Larus runnicephalus）在不同繁殖阶段的活动性，以及与人和鸟的关系进行了研究。对6只棕头鸥个体的遥测结果表明，繁殖初期棕头鸥的活动区较大，进入繁殖中期，活动区明显变小；随后繁殖后期的活动区面积有所增加，到了迁徙前期，活动区面积已接近繁殖初期。不同阶段活动区核心面积（50％ Fixed Kernel）与活动区变化趋势基本一致。繁殖初期、中期、后期和迁徙前期活动区面积分别为（15.48km^2±4．54km^2）、（1．61km^2±0．41k^m2）、（3．53km^2±2．63km^2）和（11．61km^2±9．36km^2）。棕头鸥在不同繁殖阶段的日活动区大小有显著差异。繁殖初期，棕头鸥经常活动于鸬鹚岛、蛋岛和布哈河口，它们都是棕头鸥较好的取食地，鸬鹚岛和蛋岛由于有许多游客投喂食物；在繁殖中期，棕头鸥进入孵化阶段，活动区较繁殖前期明显缩小。由于湟鱼返回布哈河口一带产卵繁殖，棕头鸥经常聚集在此地取食；在繁殖后期，棕头鸥需要寻找大量的食物进行育雏，因此活动范围再度扩大；进入迁徙前期，幼鸟已经长大并学会飞翔，其活动区进一步扩大，与繁殖初期较为接近。

卫星跟踪青海湖繁殖地渔鸥的迁徙路线

2006年7月下旬至2007年7月底,共有4只佩带卫星信号发射器(PTT)的渔鸥完成秋季和春季迁徙并返回青海湖。ARGOS公司提供的信息表明,渔鸥最早离开青海湖繁殖地的时间是8月2日,最晚在8月14日。离开青海湖后没有直接飞往越冬地,而是在青海湖周围游荡或逗留。游荡或逗留地点距离青海湖最近约200km,最远约1300km,逗留时间长达80余天。4只渔鸥的越冬地点都在孟加拉湾,与青海湖间的直线距离约2100km。最早到达越冬地的日期是11月3日,最迟12月3日,历时81～116d。渔鸥在孟加拉湾的居留时间长达4个月(118～149d)。最早离开的日期是3月1日,最迟3月30日。最早返回青海湖的日期是3月23日,最迟4月17日。除1只以外,其他3只渔鸥的春、秋2季迁徙路线很不相同。春季迁徙历时最短只用6d,另外3只分别历时15、18和32d。历时32d的渔鸥先到宁夏逗留20d,然后再返回青海湖。结合分析春、秋2季的迁徙路线,分别确定了不同迁徙季节的主要停歇地点。

新疆艾比湖湿地自然保护区鸟类清单及秋季迁徙数量统计

新疆物种多样性项目组在近10年中多次考察丁艾比湖区（44°50＇N,82°50＇E,海拔189 m）.特别是2007～2009年逐月环湖考察,包括阿拉山口、奎屯河、精河、博尔塔拉河、科克巴斯陶、桑德库木、甘家湖、古尔图等,东西长118 km,南北宽56 km,覆盖6608 km2.采用样线法和点计数法对艾比湖区不同区域鸟的种类和数量进行统计和分析.记录到233种鸟类,是全疆种数的55%,分别隶属于17目53科128属.秋季一次统计到103 875只鸟类.首次发现了卷羽鹈鹕Pelecanus crispus、白头硬尾鸭Oxyura leucocephala、遗鸥Larus relictus和细嘴鸥Larus genei等的聚集地.另有夜鹭、小白额雁、斑背潜鸭、长尾鸭、剑鹆、小滨鹬、细嘴鸥、黄腹鹨等8种为新疆新纪录种.区系以占北种（183种,78.5%）和广布种（49种,21.0%）为主,极少东洋种.艾比湖为中哑鸟类迁徙的重要驿站.

修剪与覆盖对黄土丘陵区枣林土壤干层的修复效应

【目的】探究修剪与覆盖对黄土丘陵区旱作枣林土壤水分的影响,为该区林地土壤干层修复提供科学依据。【方法】2012—2015年,以典型黄土丘陵区枣林及农田为研究对象,设计10种试验处理:常规(PI-1)、轻度(PI-2)、中度(PI-3)、重度(PI-4)修剪;林下秸秆、石子覆盖、地膜覆盖、林下裸地;PI-4+塑料膜覆盖;农地。并采用中子水分仪定位监测土壤剖面水分含量,探讨不同处理下的土壤水分状况。【结果】与相似条件下的旱作农地相比,15龄旱作山地枣林土壤干层深度达560 cm,年均耗水量高出农地19.7 mm;不同修剪处理间,枣林土壤含水量存在显著差异(P<0.05),4种修剪处理土壤含水量表现为PI-1<PI-2<PI-3<PI-4;在常规修剪情况下,采取林下秸秆、石子覆盖和地膜覆盖的枣林地土壤水分含量都显著增加(P<0.05),分别比林下裸地土壤储水量增加31.8~43.1、69.9~71.4和84.0~92.7 mm;地膜覆盖储水量在枣林休眠期达339.45 mm,显著高于石子覆盖和林下秸秆处理(P<0.05);PI-4+塑料膜覆盖处理土壤水分与农地土壤水分在枣林生育期无显著差异(P>0.05),但在休眠期枣林土壤含水量高于农地。【结论】增加枣树修剪强度可明显减少林地耗水;全年林地覆盖更有利于生育期土壤水分储存并可有效降低林地休眠期土壤水分损失;适度修剪+全年地膜覆盖可有效防治林地土壤干层加重或发生。

江苏盐城黑嘴鸥繁殖期不同阶段行为时间分配及活动规律

1999— 2 0 0 2年夏季对江苏盐城黑嘴鸥繁殖期不同阶段行为时间分配及活动规律进行了定量研究。结果表明 :繁殖前期黑嘴鸥各种行为具有较强的规律性 ,其出现频率依次为 :取食 39 36 % ,休整 37 95 % ,运动 9 4 8% ,警戒 8 30 % ,饮水 5 0 3% ;繁殖后期黑嘴鸥成鸟的各种行为不具明显的规律性 ,其出现的频率依次为取食 4 2 5 3% ,休整 1 4 2 1 % ,运动 1 7 6 5 % ,警戒 1 4 5 2 % ,饮水 1 0 93%。繁殖后期运动和警戒行为所花费的时间比繁殖前期显著增加 (P <0 0 0 1 ) ,休整行为显著减少 (P <0 0 0 1 ) ,导致这种差异性主要是取食地点的变化和后期的育雏行为。黑嘴鸥雌雄抱孵时间比为 1 2 4∶1。抱孵时间随孵化天数的增加而相应延长 ,一次抱孵时间最长可达到 2 0 1min。