南极的贝氏肩孔鰧

贝氏肩孔鰧 Trematomus bernacchii Boulenger(图1)属鲈形目(Perciformes)南极鰧科(Nototheniidae)分布于南极洲沿岸的海域内。标本系我国初访南极的董兆乾同志于     

呵护贝类家园，造福人类千秋

形貌奇异、色彩绚丽、斑纹精致和种类繁多的贝类是大自然最令人叹为观止的造物之一。贝类属软体动物,是动物界第二大类群,至今已记载13万种之多,其中包括化石种类3.5万种。贝类在地球上广泛分布,从南极沿岸潮间     

南极彭拉阿里岛和斯迪根特角企鹅繁殖群体的生物学考察

企鹅在南极海洋生态系中占有重要的地位,曾有不少生物学家对其形态特征和生态分布进行过观测。但对南设特兰群岛东北部的费尔德斯湾(Fildes Bay)沿岸和斯迪根特角(Cape Stigant)的企鹅群体尚未见有研究报导。作者于1982年11月下旬至12月中旬曾数次去彭拉·阿里岛(Penla Arlley Island)和斯迪根特角对巴布亚企鹅(Pygoscelis papua),阿德雷企鹅(P.adeliae)和安达蒂卡企鹅(P.antarctica)的繁殖地进行考察,获得下列结果。一、工作地点彭拉·阿里岛方圆只有5公里,其西南部有一条长约500米,宽约4—8米的小径与费尔德斯半岛(Fildes Peninsula)…     

企鹅

企鹅是生活在南半球,而且善于游泳和潜水的海鸟。它隶属于鸟纲、楔翼总目(Impennes)、企鹅目(Sphenisciformes)、企鹅科(Spheniscidae)。企鹅主要分布在南极洲沿岸。寒冷给南极造成一种特殊恶劣的生活环境,使得一般生物无法在那里生活。可是,企鹅在南极附近地区却安然无恙,这有其历史发展上的因素。也有人认为与企鹅具长期绝食能力(达4个月之久),它们在陆地上常常直立行走,并且站在海岸上远眺企望,因而有了“企鹅”的名称。企鹅的英文名称是penguin,penguin导源于拉丁文的penguis,意思是肥     

保护南极植物和地衣

正在国家海洋局极地考察办公室的支持下,我们于2012年正式启动了"南极植物保护与管理问题研究"专的题。本专题针对南极植物及微生物保护这个重要内容,以南极半岛、拉斯曼丘陵和维多利亚地等区域的植物和微生物的种类组成、分布、数量等为研究对象,结合南极条约《环境议定书》附件2的相关规定,对保护南极植物,防止外来物种损害南极生态环境,对南极植物采集等行为进行有效管控,为科学规范管理我国在     

南极鱼类多样性和适应性进化研究进展

南极地区是地球上唯一未被人类活动大量影响的地区, 其极端寒冷的环境为南极生物的进化提供了“温床”。过去三千万年间, 南极鱼亚目鱼类在南极海洋逐渐变冷的过程中快速进化, 从一个温暖海域的底栖祖先分化成南极海域最为多样化的鱼类类群。由于其在南极圈内和南极圈外的各种温度区间都有分布, 因而成为研究鱼类适应性进化和耐寒机制的良好生物模型。本文综述了有关南极海域鱼类区系组成与物种多样性现状, 南极鱼亚目鱼类适应低温的一系列特化的生物学性状及其关键的遗传进化机制。现有研究表明: 南极鱼类在几千万年零度以下低温环境的进化中发生了大量基因的大规模扩增和基因表达的改变, 如铁调素、卵壳蛋白和逆转座子等118个基因发生了显著的扩增。另外, 有些从南极鱼中获得的抗寒基因已经用于提高动植物低温抗性的研究并取得了良好的效果。在今后的几年中, 将会有多个南极鱼物种的全基因组得到破译, 在低温适应相关基因的功能和进化方面的研究也会更加深入, 这些研究将深入揭示低温压力下基因组的进化规律以及鱼类低温适应的分子机制。     

皱纹盘鲍人工育苗的初步研究

鲍是珍贵的海产软体动物,软体部非常发达,肉质细嫩,味道鲜美,誉为海味之冠,其贝壳可作中药,称石决明,为海产药用动物的重要种类。 鲍属广泛分布于太平洋、大西洋、印度洋,约90种。在北美太平洋沿岸,日本沿岸和澳洲沿岸鲍的种类与数量比较丰富。我国的广东、福建、台湾、山东和辽宁等省沿海也有     

南大洋蓝细菌和微微型光合真核生物的丰度与分布

1989/1990年南半球夏季,在自Valporaiso至Melbourne的南太平洋、南大西洋和南印度洋的广阔海域观测研究了表层水微微型光合浮游生物,包括蓝细菌和微微型光合真核生物的丰度与分布及其环境制约.结果表明,蓝细菌的丰度以亚热带海域最高,亚南极海域次之,南极海域最低,总的分布范围为 1.34～5.13 log(cell/cm³).蓝细菌丰度随纬度的增高和水温的降低而降低,其对数值与水温呈现极好的正相关(P<0.001),即使在水温变幅仅-0.3～2.1℃的绕极海域观测结果也是如此.这充分证明了蓝细菌在极地海洋的存在和水温是制约其丰度与分布的主要因子.而微微型光合真核生物丰度对水温变化的反应不如蓝细菌敏感,其变化幅度为1.54～4.50log(cell/cm³),然而在绕极海域其对数值与水温呈现极好的负相关(P<0.001),这可能是由于随着水温降低,距冰缘区越近,表层水体稳定度增大,有利于真核生物增长所致.     

南极硅藻生物多样性及生态分布研究进展

南极硅藻在南极生态系统中起着至关重要的作用, 是南极食物网的基石, 其物种多样性、群落结构特征直接或间接影响南极生态系统的稳定性。根据近30 年来国内、外有关南极硅藻的多样性和生物地理学研究, 综述了海冰硅藻的种类组成和分布特点, 南极湖泊硅藻的物种构成特征及附生硅藻和共生硅藻多样性的研究进展, 为南极硅藻的生物多样性研究、分子生态学研究、生物地理学研究开发和利用提供参考依据。     

学术新宠——琥珀缘何成为古生物学界的研究热点

琥珀品类繁多,产地分布广泛,亚洲的中国抚顺、缅甸胡康河谷,美洲的墨西哥湾、多米尼加,欧洲的波罗的海沿岸等地区都是有名的琥珀产地.实际上除南极大陆之外的各大板块均有琥珀出产,那么缅甸琥珀又是如何能从众多琥珀中脱颖而出,成为古生物学者争相探求的研究热点的呢?     

The comparative breeding biology of Adelie and Chinstrap Penguins Pygoscelis adeliae and P. antarctica at Signy Island, South Orkney Islands

Adélie Penguins and Chinstrap Penguins breed in abundance at Signy Island, South Orkney Islands, which is near the northern breeding limit of the former but in the centre of the latter's breeding range. During the 1980–81 and 1981–82 breeding seasons daily checks were made to record laying date and interval between laying, egg weight and volume, incubation period and shifts by each parent, hatching date and interval between hatching, the date on which the young first creched and their age at the time, and fledging date and age. This was done for the eggs and chicks from 60 marked nests of each species. Adelies started breeding about one month before Chinstraps and showed other adaptations which may relate to early breeding and probably to the presence of ice around the breeding site. These adaptations included longer incubation shifts and a heavier and larger first egg which may promote more rapid brood reduction. Chinstraps had shorter incubation shifts and both eggs had similar weights and volumes. Although the later breeding of Chinstraps meant that chick rearing coincided with the availability of a better food source than that utilized by Adelies, Chinstraps were unable to cope with persistent heavy ice conditions in 1980–81 and were no more successful than Adelies in 1981–82. All previous breeding data for both species are reviewed and it is suggested that early breeding by Adelies may be a consequence of competition for food with Chinstraps but, by retaining adaptations to harsh environmental conditions, Adelies are well able to breed successfully. Conversely, Chinstrap Penguins appear mainly adapted to milder environmental conditions and it is unlikely that they could compete successfully with Adelie Penguins at breeding sites on the Antarctic Continent.     

Cliff characteristics,neighbour requirements and breeding success of the colonial Cape Vulture Gyps coprotheres

The breeding success of endangered colonial nesting species is important for their conservation. Many species of Gyps vultures form large breeding colonies that are the foci of conservation efforts. The Cape Vulture is a globally threatened species that is endemic to southern Africa and has seen a major reduction in its population size (≥ 50% over 48 years). There is evidence that breeding colonies are prone to desertion as a result of human disturbance. Factors that influence the occupancy and breeding success of individual nest‐sites is not fully understood for any African vulture species. We investigated cliff characteristics and neighbour requirements of the Msikaba Cape Vulture colony, a major breeding colony in the southern node of the population in the Eastern Cape, South Africa, together with their nest‐site occupation and breeding success over 13 years. In total, 1767 breeding attempts were recorded. Nest‐sites that had a higher elevation, smaller ledge depth, greater total productivity and were surrounded by conspecifics were more likely to be occupied, although the amount of overhang above the nest was not an important predictor of occupancy. In accordance with occupation, nest‐sites with a smaller ledge depth had higher breeding success; however, nests with a greater overhang were also more successful and height of the nest‐site was not an important predictor of breeding success. The breeding success of a nest‐site in a given year was positively influenced by the number of direct nest neighbours, and nests in the middle of high‐density areas had greater breeding success. This suggests that maintaining a high nest density may be an important consideration if declines of reproducing adults continue. Breeding success declined over the study period, highlighting the effects of a temporal variation or observer bias. Our results identified optimal nest‐site locations (ledge depths of 1 m, at a height of 180 m) and their effects on breeding success. This information can be used for planning reintroduction efforts of the endangered Cape Vulture and for their ongoing conservation.     

Seasonality, depth and habitat distribution of breeding males of Oreochromis spp., 'chambo', in Lake Malawi National Park

The temporal pattern of breeding by chambo, Oreochromis spp., and the vertical and horizontal distribution of territorial males at the Golden Sands-Chembe beach were examined in the Cape Maclear region of Lake Malawi National Park. The breeding season began in September and ended in April, and the number of breeding males between 3 and 15 m was approximately 25 ha. Along the beach studied, the highest concentrations of nests were found at the ends of the beach near rocks, and the lowest number of breeding males occurred in front of Chembe village
Results from experimental gill netting demonstrated that the catches of chambo within the 100-m Lake Malawi National Park 'no fishing zone' were identical to those outside the 100-m zone, suggesting that fishermen would suffer little or no loss in catch by being encouraged to fish more than 100 m from the shore. Such a reduction in fishing and disturbance of the shallow water breeding grounds would probably enhance the chambo fishery. Preliminary data are provided on the chambo nest forms found in the Cape Maclear region, and further research is suggested to resolve the question of how many species comprise the genus Oreochromis in Lake Malawi.     

ON THE BREEDING OF THE WHITE-RUMPED SWIFT (APUS CAFFER CAFFER) IN GATOOMA

Crawford, R. J. M., Cooper, J. &; Shelton, P. A. 1982. Distribution, population size, breeding and conservation of the Kelp Gull in southern Africa. Ostrich 53:164:177.

The Kelp Gull Lams dominicanus in Africa occurs coastally between Luanda, Angola and Delagoa Bay, Moçmbique. It breeds between Cape Cross Lagoon, South West Africa/Namibia and Riet River, eastern Cape, South Africa. Censuses of nests and breeding birds at all known southern African breeding localities in the period 1976–1981 indicated that 11 199 pairs bred at 52 localities; 79.5% of this population occurred in South Africa, 57,1% in the Saldanha Bay to Dassen Island region, southwestern Cape. Of the breeding pairs 83% occurred on offshore islands and rocks. Colony size at islands is related to their surface area andMayalso be influenced by food availability and the level of human disturbance. The species breeds in a wide variety of habitats ranging from cliffs and rock stacks to wooden platforms, lowlying vegetation among sand dunes and estuarine sandbars. Any available material is used in the construction of nests, whichMaybe as dense as 4/m² Clutch size is 2–3 eggs. In 1978 breeding took place earlier in South Africa than in South West Africa/Namibia. 92% of the population breeds m sites which are legally protected. Kelp Gulls have decreased or increased in numbers at some breeding localities but there is no clear overall trend. Any increases in colony size near urban areasMayresult in added airstrike hazards.     

Chinstrap penguins (Pygoscelis antarctica) nesting on Sabrina Islet, Balleny Islands, Antarctica

Although the majority of chinstrap penguins (Pygoscelis antarctica) inhabit the Scotia Arc, a minuscule population of ten breeding pairs has been reported several times from Chinstrap Islet, in the Balleny Islands, 5,000 km distant on the opposite side of Antarctica. An aerial photographic census (December 2000) reveals that the overall penguin population of the Balleny Islands has declined by 8% since the last census 16 years ago, while the combined populations of the two largest colonies, Chinstrap Islet and Sabrina Islet, have increased by 11%. A ground visit confirmed for the first time that chinstrap penguins also breed on Sabrina Islet, occupying 20-24 nests on the margins of the Adélie colony (3,790 pairs in all). The small size and anomalous location of the Balleny Islands chinstrap population clearly warrant further study and the strongest protective measures.     

Effect of predation by skuas on breeding success of the Cape petrel Daption capense at Nelson Island, Antarctica

Breeding success of Cape petrels at Nelson Island (South Shetland Islands) in 1991/1992 averaged 29%. Predation by skuas accounted for 76% of all nesting failures. Direct attacks prevailed over opportunistic predation. Intensity of observer disturbance alone could not account for the inter-colony variation in predation rate, which tended to increase with colony size, presence of nearby breeding skuas and local availability of other prey species (penguins). Predation was significantly lower on nests that could be attacked only, or more easily, from the air and nests with close neighbours. Selective predation on nests in which relatively narrower eggs were laid was independent of nest-site characteristics and laying date, suggesting an effect of parental age/experience on breeding success through antipredator behaviour. Development of oil-spitting behaviour in growing chicks balanced the parental attendance and effort in nest defence, which declined as chick age increased. Increased predation on lighter but not smaller chicks may reflect the lower ability of such chicks to defend themselves by spitting stomach oil. Seasonal variations of predation rate on Cape petrel nests did not result from predator swamping by numbers of simultaneously active nests, but rather reflected temporal availability of alternative prey. Success of all phases of nesting declined with later laying date. Received: 15 December 1997 / Accepted: 11 April 1998     

First Red-billed Quelea breeding record in the winter rainfall region of South Africa

The Red-billed Quelea Quelea quelea is a serious pest of agricultural crops throughout most of sub-Saharan Africa. Since the 1980s, it has expanded its range into the Eastern Cape and Western Cape, South Africa, facilitated by changes in agricultural practices. This note documents the first breeding of Red-billed Quelea in the winter rainfall region of South Africa. A colony of 350–600 nests was found, with evidence of recent breeding. Red-billed Quelea numbers were low in this region, but if numbers increase in the future in the Western Cape, winter crops could be under threat.     

Off‐road vehicles affect nesting behaviour and reproductive success of American Oystercatchers Haematopus palliatus

As human populations and associated development increase, interactions between humans and wildlife are occurring with greater frequency. The effects of these interactions, particularly on species whose populations are declining, are of great interest to ecologists, conservationists, land managers and natural resource policy‐makers. The American Oystercatcher Haematopus palliatus, a species of conservation concern in the USA, nests on coastal beaches subject to various forms of anthropogenic disturbance, including aircraft overflights, off‐road vehicles and pedestrians. This study assessed the effects of these human disturbances on the incubation behaviour and reproductive success of nesting American Oystercatchers at Cape Lookout National Seashore, on the Atlantic coast of the USA. We expanded on‐going monitoring of Oystercatchers at Cape Lookout National Seashore by supplementing periodic visual observations with continuous 24‐h video and audio recording at nests. Aircraft overflights were not associated with changes in Oystercatcher incubation behaviour, and we found no evidence that aircraft overflights influenced Oystercatcher reproductive success. However, Oystercatchers were on their nests significantly less often during off‐road vehicle and pedestrian events than they were during control periods before the events, and an increase in the number of off‐road vehicles passing a nest during incubation was consistently associated with significant reductions in daily nest survival (6% decrease in daily nest survival for a one‐vehicle increase in the average number of vehicles passing a nest each day; odds ratio = 0.94; 95% confidence interval (CI) 0.90, 0.98) and hatching success (12% decrease in hatching success for a one‐vehicle increase in the average number of vehicles passing a nest each day; odds ratio = 0.88; 95% CI 0.76, 0.97). Management of vehicles and pedestrians in areas of Oystercatcher breeding is important for the conservation of American Oystercatchers.     

Breeding sites and population of seabirds on Admiralty Bay,King George Island,Antarctica

The monitoring of the status and distribution of seabird populations is necessary to understand their spatial and temporal responses to rapid climate changes occurring in the Western Antarctic Peninsula area. We surveyed and mapped Admiralty Bay bird communities and related them to climate variables—temperature, temperature anomaly, Antarctic Oscillation Index and El-Niño Southern Oscillation Index. We recorded 13 breeding seabird species over three seasons (2009/2010, 2010/2011 and 2011/2012) and mapped 10 of them over an area of 149.5 ha. The ice-free areas with the greatest number of species were Point Thomas, Keller Peninsula and Hennequin Point. The most abundant species was the Adelie Penguin (Pygoscelis adeliae) followed by the Chinstrap Penguin (P. antarcticus). We observed that the number of breeding pairs of Gentoo Penguins (P. papua), Chinstrap Penguins and skuas (Catharacta maccormicki and C. antarctica) are related to temperature, temperature anomaly and El-Niño Southern Oscillation Index. The size of breeding populations and their distributions have been fluctuating over the last 30 years in ice-free areas of Admiralty Bay. Most species showed a decreasing trend from 1978 to 2012, with the exception of Chinstrap Penguins, Southern Giant Petrels (Macronectes giganteus) and skuas, which seem to be stable in numbers in the last two decades. Decreases in seabird populations from the Antarctic Peninsula are widely recognized as a response to environmental change and anthropogenic influences such as tourism and building activities, thus highlighting the importance of monitoring to support mitigation measures.     

Reproductive isolation and the nest sites of Lake Malawi chambo, Oveochvomis (Nyasalapia) spp.

The nest sites of chambo, Oreochromis (Nyusalupia) spp. were surveyed in the vicinity of Cape Maclear, Lake Malawi. O. karongae (Trewavas) nested at depths of 0.5 to 28 m, while O. lidole bred at depths greater than 17 m. Nesting areas overlapped between these two species. O. lidole (Trewavas) nests were generally larger than those of O. karongae . Both species bred from September to March. Contrary to previous suggestions, the two chambo species were not reproductively isolated by breeding depth, season, or beach type.