太湖湿地生态系统有机氯污染的夜鹭生物指示

1999年春季,在对无锡鼋头渚鹭鸟种群野外生态调查的基础上,对夜鹭幼鸟反吐物,觅食地底泥和水体进行了采样,并在实验室用气相色谱测定了样品中的α-HCH、β-HCH、γ-HCH、艾氏剂、狄氏剂、异狄氏剂、七氯、环氧七氯、p,p'-DDE、p,p'-DDD、o,p'-DDT和p,p'-DDT等有机氯农药的残留状况,结果表明,在有机氯农药禁用近20年后,六六六的异构体和滴滴涕及其衍生物均能在环境中和夜鹭食物中有不明,在有机氯农药禁用近20年后,六六六的异构体和滴滴涕及其衍生物均能在环境中和夜鹭食物中有不明,在有机氯农药禁用近20年后,六六六的异构体和滴滴涕及其衍生物均能在环境中和夜鹭食物中有不检出,有机氯污染物沿夜鹭食物链产生逐级富集,太湖湿地生态系统中夜鹭卵富集了滴滴涕万倍以上,富集了六六六数千倍,从而使有机氯污染物易被检测,因此夜鹭锘放可作为湿地生态系统有机氯污染的生物指示物。     

南极Gerlache海峡海鸟的取食集群及食性

1997年12月至1998年2月,我们对南极半岛席尔瓦角善于飞翔海鸟与企鹅的取食关联性进行了研究,同时调查了取食集团中主要鸟种的食性.发现每个取食集团中有35.6-37.0只善于飞翔的海鸟,其中几乎都有纹颊企鹅群 (Pygoscelis antarctica),黑背鸥(Larus dominicanus)、灰贼鸥(Catharacta maccormicki)、花斑鹱(Daption capensis)和巨鹱(Macronectes giganteus)是各集团中最常见的鸟类.各取样单元内有相关性的种数随季节变化而减少,一些种类的减少与特定的物候期有关.南极磷虾(Euphausia superba)是绝大部分飞翔海鸟的主要食物,研究发现黑背鸥与纹颊企鹅所捕食的南极磷虾的大小最为接近.飞翔海鸟的觅食行为表明:在海面上短时停留的飞翔海鸟也能够成功捕捉到磷虾,这可能与磷虾躲避企鹅的捕食有关[动物学报 53(3):425-430,2007].     

巢湖表层水体中有机氯农药的分布及其组成

以固相萃取-气相色谱法/电子捕获检测器(SPE-GC/ECD)作为检测手段,对巢湖表层水体中有机氯农药(OCPs)的分布及组成特征进行分析.结果表明:研究区13个采样点中共检出包括六六六(HCHs)、滴滴涕(DDTs)、β-硫丹(β-Endosulfan)、艾氏剂(Aldrin)、六氯苯(hexachlorobenzene)和七氯(Heptachlor)在内的16种有机氯农药,其总含量范围为0.54～64.01ng.L-1;16种有机氯农药中以HCHs和DDTs为主,其平均质量浓度分别为5.56ng.L-1和16.57ng.L-1,约占其总量的84.75%;研究区的有机氯农药污染除了主要源于历史上农田中有机氯农药的残留外,近期可能还有新的农药污染源进入水环境;研究区所检出的各类有机氯农药均未超过国家地表水环境质量标准,巢湖表层水体中有机氯农药含量及潜在风险均属于中等偏低水平.     

南极生物粪对汞的生物放大作用

首次报道了南极地区金图企鹅、阿德利企鹅、黑背鸥和巨海燕 4种海鸟 ,以及象海豹、威德尔海豹、毛皮海狮等 3种海豹新鲜粪便中的全 Hg含量 ,并对比了该区风化土壤的 Hg含量 ,其中 Hg含量水平依次为 :土壤背景值 <黑背鸥粪 <金图企鹅粪 <阿德利企鹅粪 <威德尔海豹粪 <象海豹粪 <巨海燕粪 <毛皮海狮粪 ,可见 ,相对于背景土壤生物粪明显富集 Hg元素。此外 ,结合上述粪便样品的 δ15 N测定结果 ,讨论了南极生物粪对 Hg的生物放大作用。研究表明 ,随着 δ15 N升高 ,即生物营养级的升高 ,其粪便的全 Hg含量有逐步增高的趋势 ,这证实了生物粪和生物肌体一样存在对 Hg的生物放大作用。文中还对南极阿德雷岛一个经过企鹅粪污染的 Y2湖泥芯剖面上 15个样品的 2 6种元素进行了聚类分析 ,结果表明 ,沉积物中的汞和企鹅粪的标型元素具有同源性 ,即沉积物中的汞主要是由企鹅粪带入的 ,由于生物粪对汞的生物富集作用 ,生物粪的混入会造成湖泊沉积物中汞含量的增高     

长江口两种江豚亚种体脂内多氯联苯同分异构体含量的比较分析

为了弄清长江口江豚(Neophocaena asiaeorientalis)体脂内多氯联苯(PCBs)的累积情况,采用气相色谱质谱联用仪(GC-MS)对5头东亚亚种(N.asiaeorientalis sunameri)和3头长江亚种(N.asiaeorientalis asiaeorientalis)的10种多氯联苯同族物(PCBs)含量进行了测定。研究发现,长江口江豚体脂中多氯联苯(PCBs)的平均含量为3.38μg/g(湿重),其中,长江亚种的多氯联苯(PCBs)含量(3.40~12.67μg/g)要显著高于东亚亚种(0.33~2.21μg/g)。在10种多氯联苯(PCBs)中,一氯、二氯和三氯联苯在所有个体中均未测出(小于0.005μg/g),但四氯、五氯、六氯和七氯联苯在所有个体中都被测出,其中,六氯联苯的平均含量高达1.48μg/g,占总含量的43.79%。从含量的组成看,六氯联苯和七氯联苯均构成了长江口江豚体脂内多氯联苯(PCBs)的主要成分,但相比东亚亚种,长江亚种的四氯联苯和五氯联苯也占较高的比例。研究表明,低氯代组分的多氯联苯(PCBs)可以随水流的稀释和生物转化而逐渐降解,但高氯代组分的多氯联苯(PCBs)则不易降解,并且随江豚年龄的增长而快速积累,产生更持久的毒性效应。     

宁波滩涂贝类养殖区沉积物中有机氯农药和多氯联苯残留及生态风险评估

利用GC-ECD对宁波市主要滩涂贝类养殖区表层沉积物中的多氯联苯(PCBs)和有机氯农药六六六(HCHs)、滴滴涕(DDTs)的残留量进行测定,研究其分布状况,并进行生态风险评估.结果表明:贝类养殖区表层沉积物中的总有机氯农药含量为0.80～32.40ng·g-1,多氯联苯含量为3.20～33.33 ng·g-1.HCHs主要来自远距离大气传输及历史残留,部分区域有DDTs输入,其来源可能是三氯杀螨醇的使用.大部分站位的p,p’-DDT和DDTs存在潜在的生态风险,其中墙头和西店海域的p,p’-DDT残留超过生物效应中值,对底栖生物毒害效应较高.大多数站位PCBs的生态风险较低.     

三油酸酯-半渗透膜采样装置对有机氯农药的富集作用

在实验室流水条件下研究了林丹、艾氏剂、环氧七氯、4 ,4′ 滴滴涕及六氯苯在三油酸酯 半渗透膜采样器 (SP MDs)中的富集。所研究的 5种有机氯农药在SPMDs中富集迅速 ,动力学过程可以用线性关系描述 ,2 0d后富集系数达到 15 0 0— 180 0 0。当暴露于接近天然水体浓度时 (2 μg/L) ,富集量能够达到对生物标记物研究制样量的要求 ,富集量大小顺序为六氯苯 >4 ,4’ 滴滴涕 >七氯环氧 >艾氏剂 >林丹 ,与有机氯化合物的脂 /水分配系数成正相关。初步研究结果表明SPMDs可以用来作为生物标记物测试的样品前处理手段 ,或替代水体生物进行微量或痕量有毒有机污染物的生物毒性监测。     

沈阳市城郊土壤有机污染特征

对沈阳市城郊土壤中35种有机污染物进行了检测,分析了土壤有机污染检出特征和空间分布特征.沈阳市城郊土壤共检出了15种有机污染物;苯并(a)芘、六氯苯、滴滴涕和六六六的变异系数均大于l,其污染物浓度局部富集程度高,含量起伏变化大,土壤有机污染呈现“一多三少”的现象,即全区检出有机污染物的采样点多,检出的有机污染物种类较少,有机污染物含量少,且无超标点.受土壤包气带岩性影响,城郊土壤垂向上有机污染规律明显.土壤区域有机污染分布特征与城市土地利用功能一致性较高.分析了各类有机污染物含量和分布特征的主要影响因素,对防治城市土壤污染,进而保障居民的食品安全和饮水安全具有重要意义.     

多氯联苯微生物脱氯研究进展

多氯联苯(polychlorinated biphenyls,PCBs)是环境中典型的氯代持久性有机污染物.微生物脱氯是一种氯代有机物自然降解模式,对全球PCBs特别是高氯代同系物消减起到至关重要的作用.厌氧条件下高氯代PCBs能够发生脱氯反应,使其毒性大大降低,脱氯后形成的低氯代化合物可以进一步好氧降解,直至完全矿化.本文综述了PCBs生物脱氯的研究进展,介绍了微生物脱氯反应的机理和特征、参与微生物脱氯过程的专性脱氯菌等,探讨了该微生物过程的影响因素及厌氧脱氯与好氧降解耦合的意义,并对脱氯微生物群落的复杂代谢网络研究、专性脱氯新菌种筛选及其污染地实际修复应用等未来研究方向进行了展望.     

有机氯农药在东方白鹳和白鹤羽毛中的残留分析

2007年5月,采集合肥野生动物园采集东方白鹳(Ciconia boyciana)及白鹤(Grus leucogeranus)的胸部廓羽、飞羽及尾羽样品共51枚,用气相色谱法分别检测其中的op’-DDT、pp’-DDD、pp’-DDE、pp’-DDT、α-六六六、β-六六六、γ-六六六、δ-六六六及六氯苯9种有机氯农药的残留量。检测结果发现,pp’-DDD、pp’-DDE、pp’-DDT、β-六六六、δ-六六六5种有机氯农药在东方白鹳和白鹤羽毛中都有不同程度的检出,其中pp’-DDD的残留量最高,在东方白鹳的廓羽、飞羽和尾羽中的平均残留量分别达到0.8936、0.8353和0.7516μg/g干重,在白鹤的廓羽、飞羽和尾羽中的平均残留量分别达到0.5685、0.5077和0.4657μg/g干重;pp’-DDD和pp’-DDT在两种鸟胸部廓羽、飞羽及尾羽间的残留量无显著差异;pp’-DDD在东方白鹳飞羽和尾羽中的残留量显著高于白鹤。     

The first record of Brown Skua Catharacta antarctica in Europe

Evidence from mtDNA suggests that two skuas, one discovered in the Scilly Islands Cornwall in October 2001, the other in Glamorgan in February 2002, belong to the Brown Skua group Catharacta antarctica – a species not previously recorded in the North Atlantic. These molecular data do not exclude the possibility of either bird being a hybrid between Brown Skua and South Polar Skua C. maccormicki , but population estimates suggest that this is unlikely. More importantly, biometrics show that the Glamorgan bird is much smaller than hybrids but matches Falkland Skua C. a. antarctica . The distributions of C. antarctica subspecies at sea are not well known, but the discovery of two of these birds in the UK suggests that they may wander more extensively than previously thought.     

A STUDY OF THE SPECTACLED WEAVER

New species of haematozoa, namely Leucocytozoon ugwidi sp. nov. from the Cape Cormorant Phalacrocorax capensis and Haemoproteus skuae sp. nov. from the Subantarctic Skua Catharacta antarctica, are described. These are the first species to be recorded from the families Phalacrocoracidae and Stercorariidae, respectively.     

VARIATION IN THE CAPPED WHEATEAR

Williams, A. J. 1980. Aspects of the breeding biology of the Subantarctic Skua at Marion Island. Ostrich 51:160-167.

The breeding biology of the Subantarctic Skua Catharacta antarctica lonnbergi was studied in two austral summers at Marion Island. Eggs were laid between 23 October and 19 December. The clutch size was one (6%) or two (94%) eggs. The laying interval was two (20%) or three (80%) days and the incubation period was 29 days. Chicks could fly at 50–65 days after hatching. Chicks from first and second hatched eggs in the same brood had similar growth rates. Chicks in one- and two-chick broods had similar growth rates until 50 days after hatching when chicks reared singly were heavier. Egg mortality was 15,8%, chick mortality was 34,8% and the overall breeding success was 50,9%. The results are discussed in comparison with previous studies of Subantarctic and South Polar C. maccormicki Skuas.     

A technique which may allow accurate determination of the age of adult birds

Although many age determination techniques have been developed for four of the five vertebrate classes, none has been developed to determine ages of adult birds. Here we report a technique, involving counting endosteal layers in the tibia, that has allowed us accurately to determine the age (in years) of 12 dead birds of species in four different families, Fulmar Fulmarus glacialis, Shag Phalacrocorax aristotelis, Redshank Tringa totanus and Great Skua Catharacta skua, all of which had been ringed as chicks and so were of known ages up to 16 years old, but provided inaccurate results for one species, the Common Guillemot Uria aalge. Since other bird species have been found to possess endosteal layers and no species has yet been found to lack such layers, this would appear to be a technique of general applicability which could permit invaluable new work in both pure and applied fields of ornithology.     

THE PROBLEM OF CHICK LOSS IN THE SOUTH POLAR SKUA CATHARACTA MACCORMICKI

Hunger releases the aggressive behaviour commonly shown by the first chick of the two-chick brood of the South Polar Skua Catharacta maccormicki. Hunger also releases aggressive behaviour in the second chick, but asynchronous hatching usually restricts this behaviour to the first chick. The degree of hunger experienced by the first chick regulates the intensity of its aggressive behaviour, which in turn affects the second chick's survival. Aggressive behaviour restricts the second chick's access to the nest area and deprives it of parental attention, increasing its susceptibility to starvation, exposure and predation. Weight and age differences between the chicks affect neither the release of aggressive behaviour, nor the survival of the second chick.     

Survival, site and mate fidelity in South Polar Skuas Catharacta maccormicki at Anvers Island, Antarctica

In 1974–1975, 34 adult South Polar Skuas Catharacta maccormicki were colour-ringed on 18 nest territories at Bonaparte Point, Anvers Island, near Palmer Station along the Antarctic Peninsula. Subsequently, the area was searched for these birds during the austral summers of 1975–1976 to 1984–1985 and in 1987–1988 and 1989–1990. Fifty-three percent were seen in 1984–1985, 32% in 1987–1988 and 21% in 1989–1990. Annual survival rate averaged 95% from 1974–1975 to 1984–1985; no sexual differences were detected (n = 28 of known sex). Strong territory and mate fidelity were apparent: 34 skuas averaged 1.1 nest territories and 1.7 mates each in 16 years. Only 4 of 34 individuals (all females) were known to change territories, and each territory change involved a change of mates. Although males showed higher territory fidelity than females (P < 0.01), most females (four of five) retained their territories when previous mates failed to return. Seventeen of 34 birds changed mates a total of 24 times; at least 20 mate changes followed the death or disappearance of the former mate. Males showed slightly higher mate fidelity than females (P < 0.04). Female South Polar and Brown Skuas Catharacta lonnbergi did not differ in territory or mate fidelity. From 1974–1975 to 1984–1985, 120 South Polar Skua chicks were ringed on 18 nest territories on Bonaparte Point: 17 were resighted in the Palmer area when they were 3–10 years old. All 15 returnecs were found within 3 km of their natal nest sites, and four of them occupied nest territories on Bonaparte Point.     

Chick loss in the Falkland Skua Catharacta skua antarctica

Data on reproductive success of 110 Falkland Skua Catharacta skua antarctica pairs were gathered during the austral summers of 1988–1989 and 1990–1991 on New Island, Falkland Islands. Adults laid two eggs 2–3 days apart and began incubation with the first egg. For the years combined, 1.39 chicks per nest hatched and 0.84 chicks per nest fledged (fledging was defined as surviving to 16 days of age). Brood reduction was common; 43% of the two-chick broods were reduced to one, and mortality was concentrated on the younger chick. Although asynchronous hatching and differential death are consistent with Lack's brood reduction hypothesis, application of O'Connor's quantitative criterion revealed that sibling competition may not be responsible for the observed chick mortality. Furthermore, because no aggressive interactions between chicks were observed or detected indirectly, siblicide may be absent in this population. Instead, predation modified by a variety of factors may have led to the greater mortality of the second-hatched chick.     

Skuas on the Eurasian tundra; relative occurrence of species, ages and colour phases

The breeding ranges of the three closely related skua species in the genus Stercorarius are highly sympatric on the Arctic tundra. During the Swedish-Russian Tundra Ecology Expedition, 1994, the ages and colour phases of Pomarine Skuas Stercorarius pomarinus , Arctic Skuas Stercorarius parasiticus and Long-tailed Skuas Stercorarius longicaudus were recorded at 15 sites along a transect across 140̀ of longitude from the Kola Peninsula in the west to Wrangel Island in the east. An index of the lemming numbers was also measured. Pomarine Skua comprised 52% of the 1587 skuas seen, with 38% Long-tailed Skua and 10% Arctic Skua. The Arctic Skua occurred at low densities all along the transect. The Pomarine Skua was most common at the northernmost sites in this lemming year. It was absent from all sites with low rodent densities but also from two more southerly sites with high lemming numbers. The Long-tailed Skua showed a distribution sympatric with that of the Pomarine Skua but occurred at lower densities, and it also bred at the more southerly sites. No skuas in second-year plumage were observed. Older subadult skuas were observed in increasing numbers with age. The proportion of subadults was markedly higher in the Pomarine Skua (10%) compared with the two other species. The proportion of dark Pomarine Skuas was about 8% all along the transect. In the Arctic Skua, there was an extremely marked shift from 64% dark birds on the Kola Peninsula to an almost complete dominance by the light phase in the rest of Arctic Russia. I suggest that dark skuas are more efficient kleptoparasites over the sea while the light phase is at an advantage hunting over the tundra.     

Factors affecting chick growth in the South Polar Skua (Catharacta maccormicki): food supply, weather and hatching date

This study investigated chick growth in a pelagic Antarctic seabird, the South Polar Skua (Catharacta maccormicki). The factors food supply, weather and hatching date were analysed in a population of 54 breeding pairs at King George Island/South Shetland Islands. Food supply was manipulated by offering fish corresponding to 20% of daily energy demand of chicks to half of the breeding pairs every second day. Growth of mass, head, wing and tarsus was followed and related to the treatment, weather conditions, hatching date and interactive effects. Food supply did not limit chick growth in the studied season. Parents seemed to try to feed their chicks at a maximum rate and succeeded in the studied season because the general food supply was very good. Low temperatures and strong winds depressed chick growth. A growth advantage of food-supplemented chicks could be observed when the natural conditions for chick growth were sub-optimal. Chick growth rate was strongly negatively associated with hatching date and worsening weather during the reproductive season could be excluded as explanatory variable for this finding.