中国鸟类红色名录评估

中国有1,372种鸟类, 其中77种为中国特有。由于资源过度利用、栖息地丧失和片断化、环境污染等原因, 中国的鸟类多样性保护面临严峻的挑战。为了全面评估当前中国野生鸟类的濒危状况, 国家环境保护部支持启动了“中国脊椎动物红色名录”的编制工作。依照IUCN的标准, 对中国鸟类的受胁状况进行了一次全面评估。通过确定评估对象、数据收集、初评、初核、复审、定稿等步骤, 集国内27位鸟类学家的力量, 完成了本次评估。结果表明: 区域灭绝(RE)3种, 分别是白鹳(Ciconia ciconia)、镰翅鸡(Falcipennis falcipennis)和赤颈鹤(Grus antigone), 极危(CR)15种, 濒危(EN)51种, 易危(VU)80种, 近危(NT)190种; 无危(LC)876种, 数据缺乏(DD)157种。列为极危、濒危和易危等级的受胁鸟类合计146种, 占中国鸟类种数的10.6%。受威胁程度最高的科是鹈鹕科和犀鸟科, 这两个科100%的物种都属于受胁种。。77种特有鸟类中有29种(37.7%)属于受胁种。陆禽和猛禽是受胁最严重的生态类群, 分别有25.2%和23.2%的种类处于受胁状态。不同行政区域受胁鸟类差异较大。本工作对于我国鸟类保护和履行国际公约等工作均有重要意义。     

The Important Bird Areas Programme in Africa: an outline

Bennun, L. & Fishpool, L. 2000. The Important Bird Areas Programme in Africa: an outline. Ostrich 71 (1 & 2): 150–153.

BirdLife International works to conserve the world's birds at the levels of species, sites and habitats. The Important Bird Areas (IBA) programme is a process of setting site-based priorities for birds based on information about species' distribution and numbers. The African IBA programme started in 1993, building on similar successful programmes in Europe and the Middle East. Important Bird Areas are selected according to internationally agreed criteria based upon the presence of globally threatened species, species of restricted range, biome-restricted species assemblages and concentrations of numbers.

In Africa, a continental directory of sites is scheduled for publication in 2000, and work is underway to identify and document IBAs across the continent and its associated islands. In 18 countries so far, the process of compiling information is being combined at a national level with strengthening the capacity for research and action, and building effective structures (especially NGO-Government linkages) for advocacy and action. The resulting inventories can be used in numerous ways to prioritise, inform and stimulate conservation action at local and national levels.     

Threatened and endemic species: are they good indicators of patterns of biodiversity on a national scale?

Endemic and/or threatened species are often targeted to set conservation priorities. It is tempting to assume that a reserve network focusing on these species will be an effective umbrella for overall species richness of a country. For South Africa and Lesotho we tested whether complementary networks selected for threatened and/or endemic bird species satisfactorily represent all bird species, both in terms of capturing areas where other species are present or areas where they are more abundant (and, presumably, more viable). We found that areas selected for threatened and endemic species perform considerably better than areas selected at random. However, they do not guarantee the representation of overall bird species diversity, particularly not in peak abundance locations. Although nationally threatened and endemic species are important conservation targets, our results indicate that reserve networks focusing solely on these species may not be sufficient to preserve overall species diversity in a country.     

Current and future impacts of nest predation and nest-site competition by invasive eastern grey squirrels Sciurus carolinensis on European birds

1. The eastern grey squirrel (hereafter ‘grey squirrel’) is considered one of the most damaging invasive alien species in Europe, with negative effects on native ecosystems. Despite it being widely perceived as a significant predator of bird eggs and chicks and as a competitor for nest sites, evaluation of the grey squirrel’s impact on European bird populations has been hindered by limited empirical data.
2. The aim was to review the incidence of grey squirrels as nest predators of and nest-site competitors with European birds, and to use this information to identify species at potential risk of negative effects from within the grey squirrel’s expanding range in continental Europe.
3. A comprehensive literature review was conducted, and the data were used alongside additional new data, to assess nest predation and competition by grey squirrels in their current European range. Bird species were grouped by nest-site type, which was used to predict the impact on similar species groups in regions of continental Europe predicted to be colonised by grey squirrels in the current century.
4. Camera-monitoring and field evidence for 12 bird species and 12420 nests in Britain showed that grey squirrels rarely depredated eggs or chicks, affecting just 0.5% of nests. Nest-site competition was also minor, with grey squirrels occupying 0.8% of 122 small tree cavities and 14% of 57 larger cavities. At least 69 bird species in continental Europe could be exposed to potential nest predation or competition from expanding grey squirrel populations within the current century, but population-level effects currently appear to be unlikely.
5. Current evidence shows that grey squirrels are unlikely to be significant predators of or competitors with nesting birds in their present or projected range in Europe. However, further studies of more species in different regions would be valuable, particularly in urban and suburban habitats.

     

中国受胁鸟类的分布与现状分析

参照《Threatened Birds of Asia》(《亚洲受胁鸟类红皮书》),将其中记载的在中国有分布的物种与《中国濒危动物红皮书·鸟类》的物种进行比较。两者的物种组成有明显差异,仅69种鸟同时出现在两个红皮书中;《亚洲受胁鸟类红皮书》中雀形目鸟类占比例最大,而《中国濒危动物红皮书·鸟类》中鸡形目鸟类占比例最大。两个红皮书中的受胁鸟类均以森林、湿地和灌丛为主要栖息生境,而导致物种受胁的主要原因是人为干扰所造成的栖息地破坏。在地理分布方面,应用Arcview 3.2的数据处理与叠加功能,发现西南山地亚区、东部丘陵平原亚区和黄淮平原亚区以及台湾亚区受胁鸟类物种丰富度较高,其中留鸟在西南山地亚区及其周边地区相对集中,迁徙鸟在东部丘陵平原亚区及其周边地区相对集中。在保护方面,中国的显著重要鸟区中有51个是在自然保护区范围内,但还有6个尚未建立保护区,建议予以保护和重视。作者认为西南山地和台湾、海南地区的受胁鸟类面临更大的灭绝威胁,而恢复和重建退化的生态系统是保护鸟类的重要前提。     

黄河流域鸟类多样性现状、分布格局及保护空缺

黄河流域幅员辽阔, 多样的地理气候、植被类型及人类活动塑造了多样化的生物多样性格局。本研究以IUCN与国际鸟盟发布的鸟类分布图层为基础, 同时收集了黄河流域2009-2019年的鸟类实地观测记录, 包括观鸟记录、GBIF数据库、红外相机监测及其他实地调查的鸟类数据, 共得到35,026条鸟类实地观测有效记录。汇总结果显示, 黄河流域记录有鸟类物种662种, 占中国鸟类物种总数的45.81%。这些鸟类分属于23目83科, 其中雀形目物种数最多(384种, 占本目全国鸟种总数的46.83%), 其次为鸻形目(67种, 占50.00%)和雁形目(39种, 占72.22%)。黄河流域受威胁鸟类共计121种, 其中有37种和52种分别在IUCN红色名录和《中国脊椎动物红色名录》中被列为受威胁物种(即评估级别为极危、濒危或易危), 22种和73种被分别列为国家I级和II级重点保护野生动物。这些受威胁鸟种多为地栖性、体型大、营养级高或具有长距离迁徙习性的物种。黄河流域鸟类整体物种多样性由南向北递减, 以黄河上中游四川、甘肃、陕西的高原与山地内鸟种最为丰富, 而受威胁鸟类物种多样性热点区则在黄河中下游, 下游黄河三角洲及邻近平原区为受威胁鸟类最主要集中分布区。黄河流域内48个国家级自然保护区共覆盖鸟种数504种(占黄河流域鸟类总种数的76.13%), 其中受威胁鸟种92种(占黄河流域受威胁鸟种数的76.03%)。区域内国家级自然保护区大多分布在黄河上游, 对黄河下游的受威胁物种覆盖程度较低, 保护空缺较严重。对此, 我们建议着重加强中下游自然保护区建设与能力提升, 增加对中下游受威胁鸟种的保护力度, 在保护策略上应当积极探索高强度土地利用下的多样化保护机制。     

Assessing and monitoring bird populations in Africa: an overview

Bennun, L. 2000. Assessing and monitoring bird populations in Africa: an overview. Ostrich 71 (1 & 2): 214–215.

Access to reliable population data is crucial for effective conservation and management of birds. So far, relatively little attention has been paid to assessing and monitoring bird populations in Africa. This is beginning to change. Regional meetings, for example in East Africa, are discussing and defining standard methodologies, and making technical information more widely available. Researchers are using these methods to access the populations of threatened species, or those of economic value. Projects involving long-term monitoring, particularly of waterbirds, are beginning to yield results that are useful for management. Some challenges that remain include: securing institutional and financial support for long-term monitoring work; integrating monitoring efforts (especially of migratory species) across borders; understanding the ecological significance of population trends; finding robust and reliable methods to census economically important species, such as game-birds; and making accurate global assessments of the populations of threatened species.     

Tourism as a threat to critically endangered and endangered birds: global patterns and trends in conservation hotspots

More than 12 % of bird species are threatened with extinction. Numerous anthropogenic activities and processes are considered responsible for such declines, including tourism related activities. These activities often occur in global biodiversity hotspots but few studies consider the potential risks associated with tourism. The relative importance of tourism as a threat to birds was quantified using a global analysis of the threats facing critically endangered and endangered birds in the hotspots. Sixty-three critically endangered and endangered bird species are reportedly threatened by tourism. Among those 63 species, marine, coastal and aquatic birds are threatened more by tourism than was expected. Hotspots with the most species threatened by tourism are Polynesia–Micronesia and the Mediterranean Basin. This study uses individual threatening processes in a new way to characterise hotspots for conservation action, advancing previous identification criteria. Analysing hotspots in terms of the relative presence of individual threatening processes may help to more effectively direct future research in these priority regions.     

Applying red lists to the evaluation of agricultural habitat: regular occurrence of threatened birds,vascular plants,and bryophytes in field margins of Poland

Using the assessments of conservation status of flora and fauna, we discuss declining species in semi-natural field margins and stress the importance of these vanishing habitats. Seventy field margins in the diverse farmland of SW Poland were investigated with regard to their vascular plants, bryophytes and breeding birds. We checked the occurrence of threatened and conservation concern species, i.e. those listed in local, national or European threatened species lists, and birds with an unfavorable conservation status in Europe. Of a total of 673 species, 18 classified as threatened were recorded: 12 vascular plants (2.2 % of the total number of species), five bryophytes (5.6 %), and one bird species (2.0 %). Threatened plants occurred in 18.6 % of study plots, bryophytes in 20.0 % and birds in 12.9 %. Eleven bird species, noted in 95.7 % of study plots, had an unfavorable conservation status in Europe. Increasing volumes of trees and shrubs significantly increased the overall richness in each taxa. In percentage terms the occurrence of focal species in all three taxa tended to be higher in shrubby than in herbaceous and tree-lined margins. Our data demonstrate that field margins in Central European arable farmland regularly support rare and threatened species, and therefore deserve greater conservation efforts. Red lists along with alternative listing approaches can be employed to evaluate the biodiversity of fine-scale habitats, but their applicability depends on the taxonomic group and geographical scale of the lists, reflecting different conservation priorities.     

Country-based patterns of total species richness,endemicity, and threatened species richness in African rodents and insectivores

Country-based patterns of total species richness, endemicity, and threatened species richness in African rodents and insectivores are studied in this paper. We found several patterns which were similar between insectivores and rodents. Indeed, in both groups we observed: (i) a significantly uneven distribution of species richness across countries and geographic regions with highest species richness peaks being in Middle Africa and lowest peaks in Northern Africa, (ii) species richness increasing with rainfall but being independent on a country’s surface area, (iii) in each country, the insectivore total species richness and endemic species richness increases were positively correlated with rodent total species richness and endemic species richness increases. However, number of endemics peaked in South Africa and D.R. Congo in both groups, but also in Tanzania for Insectivores and in Ethiopia for rodents. In addition, the highest numbers of threatened species occurred in D.R. Congo, Rwanda and Uganda for rodents and in South Africa, Tanzania and Cameroon for insectivores. The conservation implications of these results were discussed.     

Risks to Birds Traded for African Traditional Medicine: A Quantitative Assessment

Few regional or continent-wide assessments of bird use for traditional medicine have been attempted anywhere in the world. Africa has the highest known diversity of bird species used for this purpose. This study assesses the vulnerability of 354 bird species used for traditional medicine in 25 African countries, from 205 genera, 70 families, and 25 orders. The orders most represented were Passeriformes (107 species), Falconiformes (45 species), and Coraciiformes (24 species), and the families Accipitridae (37 species), Ardeidae (15 species), and Bucerotidae (12 species). The Barn owl (Tyto alba) was the most widely sold species (seven countries). The similarity of avifaunal orders traded is high (analogous to “morphospecies”, and using Sørensen''s index), which suggests opportunities for a common understanding of cultural factors driving demand. The highest similarity was between bird orders sold in markets of Benin vs. Burkina Faso (90%), but even bird orders sold in two geographically separated countries (Benin vs. South Africa and Nigeria vs. South Africa) were 87% and 81% similar, respectively. Rabinowitz''s “7 forms of rarity” model, used to group species according to commonness or rarity, indicated that 24% of traded bird species are very common, locally abundant in several habitats, and occur over a large geographical area, but 10% are rare, occur in low numbers in specific habitats, and over a small geographical area. The order with the highest proportion of rare species was the Musophagiformes. An analysis of species mass (as a proxy for size) indicated that large and/or conspicuous species tend to be targeted by harvesters for the traditional medicine trade. Furthermore, based on cluster analyses for species groups of similar risk, vultures, hornbills, and other large avifauna, such as bustards, are most threatened by selective harvesting and should be prioritised for conservation action.     

The role of species traits and taxonomic patterns in alien bird impacts

Aim To test whether the distribution of alien bird impacts varies across bird families and regions of origin, and to investigate whether species traits associated with successful introductions can predict which species will have negative impacts in the new area of introduction. Location Europe and the Mediterranean Basin. Methods Combining historical information and published literature about negative economic, biological and human health impacts, we compared the distribution of impacts among bird families and native origins of bird species for three major types of impact (economic, biodiversity and human health). We examined the relationships between ecological, biological and reproductive characteristics of species and the severity of the impacts. Results The majority of alien species with reported impacts originated from the Afrotropical, Indo‐Malayan and Palaearctic biogeographical regions. The distribution of alien bird species in Europe with reported impacts shows a taxonomic bias and largely mirrors patterns of establishment. While most species had primarily either economic or biodiversity impacts, several species in the Anatidae, Corvidae, Passeridae, Phasianidae and Sturnidae families were associated with moderate to serious negative impacts on both economic resources and native biodiversity. After controlling for taxonomic effects, species with the greatest overall impacts were habitat generalists and multi‐brooded, while species with smaller bodies and the tendency to form large feeding or roosting flocks were linked with greater impacts on native biodiversity. Main conclusions This study presents the first synthesis of published impact data for alien birds and provides a broad‐scale perspective on factors that contribute to their impacts. The results show that accounting for both species traits and taxonomy improves our ability to predict the impacts of alien bird species. Because several species are currently in the early stages of establishment in Europe, there may be an opportunity to limit negative impacts with efforts that promote proactive strategies against species and families possessing the above characteristics.     

Ecological and socio-economic factors affecting extinction risk in parrots

Parrots (Psittaciformes) are among the most threatened bird orders with 28 % (111 of 398) of extant species classified as threatened under IUCN criteria. We confirmed that parrots have a lower Red List Index (higher aggregate extinction risk) than other comparable bird groups, and modeled the factors associated with extinction risk. Our analyses included intrinsic biological, life history and ecological attributes, external anthropogenic threats, and socio-economic variables associated with the countries where the parrot species occur, while we controlled for phylogenetic dependence among species. We found that the likelihood of parrot species being classified as threatened was less for species with larger historical distribution size, but was greater for species with high forest dependency, large body size, long generation time, and greater proportion of the human population living in urban areas in the countries encompassing the parrots’ home ranges. The severity of extinction risk (from vulnerable to critically endangered) was positively related to the per capita gross domestic product (GDP) of the countries of occurrence, endemism to a single country, and lower for species used as pets. A disproportionate number of 16 extinct parrot species were endemic to islands and single countries, and were large bodied, habitat specialists. Agriculture, hunting, trapping, and logging are the most frequent threats to parrots worldwide, with variation in importance among regions. We use multiple methods to rank countries with disproportionately high numbers of threatened parrot species. Our results promote understanding of global and regional factors associated with endangerment in this highly threatened taxonomic group, and will enhance the prioritization of conservation actions.     

Angola’s central scarp forests: patterns of bird diversity and conservation threats

Despite Angola’s central scarp forests being recognised as a critical global priority for bird conservation, fine-scale information on threatened bird distributions and patterns of bird diversity are lacking. These data are essential to identify sites within the Western Angola Endemic Bird Area that should be targeted for conservation. First endemic and near-endemic species and subspecies, and species with isolated populations along the Angolan scarp were identified to highlight taxa of greatest priority for conservation and for use in studying the evolutionary origins of the region. Thereafter survey data collected during 2005 from 13 forest sites along the central scarp was analysed. These data show that there are three distinct bird communities across the width of the escarpment, each associated with a distinctive forest type. Of note is the finding that threatened and Near Threatened endemic species occur almost exclusively in the dry forests adjacent to the main escarpment, rather than in the moistest forests found on the main escarpment, which instead are richer in Congo Basin forest birds. Based on these data, summaries of ranges, populations and conservation threats are given for the seven most threatened bird species. Attention is drawn to threats to the habitats of greatest importance to these species. A conservation area network should be established that encompasses the full spectrum of bird diversity described, to ensure survival of current unique taxa and the future evolutionary potential of the area.     

Mechanisms of population dynamics in trans-Saharan migrant birds: A review

Modern views on the mechanisms of population dynamics in Palearctic birds wintering in tropical Africa are discussed with regard to the distribution of migrants on the African continent and the influence of external factors on conditions of bird wintering. The data on long-term bird trapping at ten ornithological stations in Europe are analyzed. Among 142 long-term trends in the population dynamics of 18 bird species, 34% are negative, 11% are positive, and the remaining trends lack statistical significance. The proportion of negative trends in each species negatively correlates with the number of birds: the more abundant the species, the lower the probability of its long-term population decline. Population dynamics may largely be determined by environmental conditions in wintering regions. Population studies on ten Palearctic species showed that drastic population declines and even local extinction of birds in recent decades resulted from the dramatic decrease in their survival on African wintering grounds because of insufficient precipitation and, in particular, severe droughts in the Sahel.     

Spatial Assessment of Amphibian Chytrid Fungus (Batrachochytrium dendrobatidis) in South Africa Confirms Endemic and Widespread Infection

Chytridiomycosis has been identified as a major cause of global amphibian declines. Despite widespread evidence of Batrachochytrium dendrobatidis infection in South African frogs, sampling for this disease has not focused on threatened species, or whether this pathogen poses a disease risk to these species. This study assessed the occurrence of Bd-infection in South African Red List species. In addition, all known records of infection from South Africa were used to model the ecological niche of Bd to provide a better understanding of spatial patterns and associated disease risk. Presence and prevalence of Bd was determined through quantitative real-time PCR of 360 skin swab samples from 17 threatened species from 38 sites across the country. Average prevalence was 14.8% for threatened species, with pathogen load varying considerably between species. MaxEnt was used to model the predicted distribution of Bd based on 683 positive records for South Africa. The resultant probability threshold map indicated that Bd is largely restricted to the wet eastern and coastal regions of South Africa. A lack of observed adverse impacts on wild threatened populations supports the endemic pathogen hypothesis for southern Africa. However, all threatened species occur within the limits of the predicted distribution for Bd, exposing them to potential Bd-associated risk factors. Predicting pathogen distribution patterns and potential impact is increasingly important for prioritising research and guiding management decisions.     

The impact of shrub encroachment on savanna bird diversity from local to regional scale

Aim  Evidence is accumulating of a general increase in woody cover of many savanna regions of the world. Little is known about the consequences of this widespread and fundamental ecosystem structural shift on biodiversity.
Location  South Africa.
Methods  We assessed the potential response of bird species to shrub encroachment in a South African savanna by censusing bird species in five habitats along a gradient of increasing shrub cover, from grassland/open woodland to shrubland dominated by various shrub species. We also explored historical bird species population trends across southern Africa during the second half of the 20th century to determine if any quantifiable shifts had occurred that support an ongoing impact of shrub encroachment at the regional scale.
Results  At the local scale, species richness peaked at intermediate levels of shrub cover. Bird species composition showed high turnover along the gradient, suggesting that widespread shrub encroachment is likely to lead to the loss of certain species with a concomitant decline in bird species richness at the landscape scale. Finally, savanna bird species responded to changes in vegetation structure rather than vegetation species composition: bird assemblages were very similar in shrublands dominated by Acacia mellifera and those dominated by Tarchonanthus camphoratus .
Main conclusions  Shrub encroachment might have a bigger impact on bird diversity in grassland than in open woodland, regardless of the shrub species. Species recorded in our study area were associated with historical population changes at the scale of southern Africa suggesting that shrub encroachment could be one of the main drivers of bird population dynamics in southern African savannas. If current trends continue, the persistence of several southern African bird species associated with open savanna might be jeopardized regionally.     

How to meet the 2020 GSPC target 8 in Europe: priority-setting for seed banking of native threatened plants

The contribution of the European Native Seed Conservation Network (ENSCONET, 2004-2009) and the ENSCONET Consortium (since 2010) towards meeting the 2020 Global Strategy for Plant Conservation (GSPC) target 8 was assessed in 2017. While the outcome was positive (62.7% of European threatened species already conserved ex situ in seed banks), the analysis showed that it was essential to provide guidance on which European native threatened species should be collected as a priority if the target was to be reached by 2020. In this paper we present a priority-setting method and its result, designed to guide collecting strategies across Europe to meet the 2020 GSPC target 8. The result of our study is a country-based checklist of European threatened taxa to be collected and stored ex situ across the seed banks of the ENSCONET Consortium by 2020. After discussing the results of the applied method, the ENSCONET Consortium Steering Committee has identified some key action points to support the implementation of such a collecting strategy across Europe in order to meet the 2020 GSPC target 8 for Europe.     

Founder populations and the current status of exotic parrots in South Africa

Parrots (families Psittacidae and Cacatuidae) are one of the most threatened taxa of birds, with a combination of threats to wild populations, including capture for the cage bird market, habitat modification and destruction, persecution, disease, and threats from introduced species. As a result of the group's popularity as a cage bird, and the transport of vast numbers of individuals across the globe (both legally and illegally), the establishment of populations beyond their natural ranges has likely been enhanced. This review reports on c. 30 parrot species that have been observed outside of their natural ranges in South Africa, most likely derived, and supplemented, from both intentional and unintentional releases. Of these, the Rose-ringed Parakeet Psittacula krameri and at least one Agapornis species have become established as breeding wild populations. Like other invasive species they may pose threats to local biodiversity; however, all are strongly associated with major urban centres where significant changes to natural biota have already occurred.     

Survey completeness of a global citizen-science database of bird occurrence

Measuring the completeness of survey inventories created by citizen-science initiatives can identify the strengths and shortfalls in our knowledge of where species occur geographically. Here, we use occurrence information from eBird to measure the survey completeness of the world's birds in this database at three temporal resolutions and four spatial resolutions across the annual cycle during the period 2002 to 2018. Approximately 84% of the earth's terrestrial surface contained bird occurrence information with the greatest concentrations occurring in North America, Europe, India, Australia and New Zealand. The largest regions with low levels of survey completeness were located in central South America, northern and central Africa, and northern Asia. Across spatial and temporal resolutions, survey completeness in regions with occurrence information was 55–74% on average, with the highest values occurring at coarser temporal and coarser spatial resolutions and during spring migration within temperate and boreal regions. Across spatial and temporal resolutions, survey completeness exceeded 90% within ca 4–14% of the earth's terrestrial surface. Survey completeness increased globally from 2002 to 2018 across all months of the year at a rate of ca 3% yr^–1. The slowest gains occurred in Africa and in montane regions, and the most rapid gains occurred in India and in tropical forests after 2012. Thus, occurrence information from a global citizen-science program for a charismatic and well-studied taxon was geographically broad but contained heterogeneous patterns of survey completeness that were strongly influenced by temporal and especially spatial resolution. Our results identify regions where the application of additional effort would address current knowledge shortfalls, and regions where the maintenance of existing effort would benefit long-term monitoring efforts. Our findings highlight the potential of citizen science initiatives to further our knowledge of where species occur across space and time, information whose applications under global change will likely increase.