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Report On The Nest Record Scheme, 1958, by J. F. Burton  相似文献   

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山东半岛滨海沙滩前缘的野生植物   总被引:3,自引:0,他引:3  
滨海沙滩是以海水影响为基本过程的地貌类型, 适应这种环境的植物类群与适生于内陆的沙地植物可能存在巨大差别。在野外调查的基础上, 分析了山东半岛滨海沙滩前缘的植物种类及其种间关系。结果表明: (1) 滨海沙滩前缘具有独特的优势种库, 包括沙钻苔草(Carex kobomugi)、肾叶打碗花(Calystegia soldanella)、粗毛鸭嘴草(Ischaemum bartatum)、单叶蔓荆(Vitex trifolia var. simplicifolia)、矮生苔草(Carex pumila)和沙引草(Messerschmidia sibirica)等; (2) 优势种库的成员都是潜在优势种, 它们之间主要呈抑制效应, 对库外物种几乎没有抑制效应, 甚至有互补或互利效应。在进化过程中, 这些潜在优势种可能已适应风暴潮的干扰, 不会因受风暴潮灾害而灭亡。当植物适应风暴潮后, 滨海沙滩不再是灾难环境, 反而变为适宜生境。为持续利用这些物种, 不仅要保护其赖以生存的天然生境, 还要开展引种栽培, 消除人们对野生资源的采挖动机。根据物种间的天然联系, 栽培时宜将具有互利或互补关系的物种间混种植, 不宜将具有抑制关系的物种间混种植。  相似文献   

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山东半岛滨海沙滩前缘的野生植物   总被引:1,自引:0,他引:1  
滨海沙滩是以海水影响为基本过程的地貌类型,适应这种环境的植物类群与适生于内陆的沙地植物可能存在巨大差别。在野外调查的基础上,分析了山东半岛滨海沙滩前缘的植物种类及其种间关系。结果表明:(1)滨海沙滩前缘具有独特的优势种库,包括沙钻苔草(Carex kobomugi)、肾叶打碗花(Calystegia soldanella)、粗毛鸭嘴草(Ischaemum bartatum)、单叶蔓荆(Vitex trifolia var.simplicifolia)、矮生苔草(Carex pumila)和沙引草(Messerschmidia sibirica)等;(2)优势种库的成员都是潜在优势种,它们之间主要呈抑制效应,对库外物种几乎没有抑制效应,甚至有互补或互利效应。在进化过程中,这些潜在优势种可能已适应风暴潮的干扰,不会因受风暴潮灾害而灭亡。当植物适应风暴潮后,滨海沙滩不再是灾难环境,反而变为适宜生境。为持续利用这些物种,不仅要保护其赖以生存的天然生境,还要开展引种栽培,消除人们对野生资源的采挖动机。根据物种间的天然联系,栽培时宜将具有互利或互补关系的物种间混种植,不宜将具有抑制关系的物种间混种植。  相似文献   

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为探讨鸟市贸易对野生鸟类的威胁与影响,给当地野生动物保护部门实施监管提供科学依据,于2016年11月—2017年11月对黑龙江省哈尔滨市最大鸟市——道外花鸟鱼市场进行调查。结果发现:(1)共记录6目34科83属117种18 729只鸟类,其中野生鸟类5目32科77属108种11 662只。有出售国家保护鸟种黄胸鹀 Emberiza aureola、猛禽及非法捕猎工具的现象。(2)所有被贩卖的野生鸟类中,在黑龙江省有分布的共69种,数量达9 707只。相关分析结果表明,黑龙江省有分布的野生鸟类是鸟市非法捕捉及贩卖的主要对象。(3)贩卖量为春、秋季多,夏、冬季少,7—10月鸟类迁徙季节时最多,占总贩卖量的45.2%,说明鸟类秋季迁徙是非法猎捕的高峰期。(4)调查中发现较多的南方鸟种(32.4%)也一定程度上说明野生鸟类非法运输的严重性。建议当地林业和草原局及时加强对道外花鸟鱼市场的监管,在鸟类迁徙季节从非法捕捉和运输环节实施严厉打击。  相似文献   

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《Ibis》1941,83(3):462-463
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This communication presents and discusses the financial costs recorded by a small Brazilian aviary in which a few captive-bred wild bird species have been kept. The highest expenses were associated with the birds’ diet, accounting for at least 60% of total costs. Among insectivorous-frugivorous birds, this figure was 88%. The most expensive food item was live food. Although initial costs for enclosures may be considerable, their durability means expenditures can be spread over time, mitigating their impact. Approximately 30% of the total costs for keeping the largest species studied here were linked to a spacious outdoor planted aviary. Quail from this flock required additional sanitary expenditure (i.e. 14% of the total) for controlling a previous parasitic infection. Total annual maintenance costs amounted to USD 298.00, USD 211.00 and USD 116.00 for each Pekin robin (Leiothrix lutea Scopoli, 1786), Livingstone's turaco (Tauraco livingstonii Gray, 1864), and Valley quail (Callipepla californica Shaw, 1798), respectively.  相似文献   

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J. W. Macdonald 《Bird Study》2013,60(3):147-167
The 1984 census revealed that the population of Little Ringed Plovers summering in Britain had increased by approximately 30% since 1973 to a minimum of 608 pairs, thus continuing the upward trend which began in the 1940s. There was an extension of range westwards and an expansion within the northern part of the existing range. The population changed very little in the south, where it is possible that the available habitat is now fully occupied, although interaction with Ringed Plovers Charadrius hiaticula¸ may be a limiting factor in places. Some concern must he expressed for the long-term future of the species in Britain as it depends largely on man-made habitats, free of vegetation, for breeding.  相似文献   

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ABSTRACT After mostly freshwater replaced agricultural drainage water used for wetland management in 1985, Selenium (Se) concentrations in 3 wintering waterfowl species and black-necked stilts (Himantopus mexicanus) from the North and South Grasslands of central California, USA, declined in the years from 1986 to 1988 and 1989 to 1994. However, Se concentrations were still above the threshold for potential reproductive impairment and exceeded background levels for some species. Consequently, we measured Se concentrations in aquatic birds in 2005 after long-term use (20 yr) of predominately freshwater for wetland management in the Grasslands. As in 1986–1994, Se concentrations in 2005 were higher for birds from the South Grasslands, which historically received more undiluted drainage water compared with the North Grasslands. Liver Se concentrations for stilts from the South Grasslands were at levels associated with potential reproductive impairment. All species from the South Grasslands, as well as mallards (Anas platyrhynchos), northern pintails (A. acuta), and American coots (Fulica americana) from the North Grasslands, were above species-specific background levels. From 1994 to 2005, Se levels in some aquatic birds stabilized above background levels likely indicating long-term cycling within the Grasslands. We recommend Se-contaminated drainage water (≥ 2 ppb Se) not be used for management or allowed as an input into arid wetlands throughout the western United States.  相似文献   

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Mongolia combines a near absence of domestic poultry, with an abundance of migratory waterbirds, to create an ideal location to study the epidemiology of highly pathogenic avian influenza virus (HPAIV) in a purely wild bird system. Here we present the findings of active and passive surveillance for HPAIV subtype H5N1 in Mongolia from 2005–2011, together with the results of five outbreak investigations. In total eight HPAIV outbreaks were confirmed in Mongolia during this period. Of these, one was detected during active surveillance employed by this project, three by active surveillance performed by Mongolian government agencies, and four through passive surveillance. A further three outbreaks were recorded in the neighbouring Tyva Republic of Russia on a lake that bisects the international border. No HPAIV was isolated (cultured) from 7,855 environmental fecal samples (primarily from ducks), or from 2,765 live, clinically healthy birds captured during active surveillance (primarily shelducks, geese and swans), while four HPAIVs were isolated from 141 clinically ill or dead birds located through active surveillance. Two low pathogenic avian influenza viruses (LPAIV) were cultured from ill or dead birds during active surveillance, while environmental feces and live healthy birds yielded 56 and 1 LPAIV respectively. All Mongolian outbreaks occurred in 2005 and 2006 (clade 2.2), or 2009 and 2010 (clade 2.3.2.1); all years in which spring HPAIV outbreaks were reported in Tibet and/or Qinghai provinces in China. The occurrence of outbreaks in areas deficient in domestic poultry is strong evidence that wild birds can carry HPAIV over at least moderate distances. However, failure to detect further outbreaks of clade 2.2 after June 2006, and clade 2.3.2.1 after June 2010 suggests that wild birds migrating to and from Mongolia may not be competent as indefinite reservoirs of HPAIV, or that HPAIV did not reach susceptible populations during our study.  相似文献   

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It is unclear whether the behavioral effects of peptides in laboratory studies always reflect natural conditions. Here we test whether we can detect measurable behavioral changes after rapidly injecting peptides into the brains of wild birds. We used a modified stereotaxic-like technique to inject corticotrophin-releasing factor (CRF) and arginine vasotocin (AVT, the nonmammalian form of arginine vasopressin), two hormones important in the stress response, into the brains of wild, freely behaving, male white-crowned sparrows (Zonotrichia leucophrys). We then monitored subsequent territorial behavior to determine whether CRF or AVT altered this behavior. Surprisingly, the potent stressors of capture and surgery did not eliminate territorial behavior, with many birds resuming territorial defense within 60–90 min after surgery. Centrally acting CRF, however, significantly reduced territorial defense whereas centrally acting AVT had no effect. These results indicate that the behavioral affects of peptides can be studied under natural conditions.  相似文献   

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《Ibis》1932,74(4):625-632
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2002年12月~2004年12月,对成都市区公共绿地的野生鸟类进行了调查,获见野生鸟类167种,加上文献记载的共有247种;其中白头鹎、红头长尾山雀、白颊噪鹛、麻雀为优势种.与20年前相关调查比较,增加了22种新纪录种.市区植被多样性、食源丰富以及市民保护鸟类的文明行为,对野生鸟类数量的增加起重要作用.  相似文献   

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