南京江心洲鸟类群落特征

2004～2006年,分冬夏两季对南京江心洲4种典型生境(居民区、农田区、林区及湿地区)的鸟类资源进行了调查。共记录鸟类67种,隶属10目25科。对冬夏两季不同生境中鸟类群落的密度、现存生物量、多样性指数、均匀度、优势度的对比研究表明,冬季鸟类密度、物种多样性和均匀度均高于夏季,而优势度、现存生物量则夏季高于冬季。在不同生境中,林区鸟类密度、多样性指数最高;居民区优势度最高;均匀度指数冬季林区最高,夏季居民区最高。     

部分山雀科鸟类的DNA条形码与物种识别

近年来,DNA条形码(DNA barcodes)被认为是鸟类物种识别和分类的有效手段。采用遗传距离和构树这两种方法检验了线粒体基因COⅠ片断作为DNA条形码区分包括长尾山雀在内的山雀科鸟类的识别效果。此次实验分析了92条COⅠ序列,其中50条来自GenBank,代表了该科的30个物种。分析结果表明:尽管山雀科鸟类呈现出较大的种内变异,但是该科鸟类的种间遗传距离还是远大于种内的遗传距离。COⅠ条形码可识别出大部分的山雀科物种,同时该条形码还可鉴定出亚种组、亚种、甚至地理种群。然而,对于近期分化和存在杂交的物种,COⅠ难以鉴定出。在此情况下,探索应用核基因条形码或者采用基于碱基属性的鉴定方法则可以弥补这一缺陷。比较古北界、东洋界与新北界(北美)的山雀类发现,古北界和东洋界的山雀具有较大的种内变异且种群内具有较大的遗传分化,推测这很可能和第四纪冰川的影响有关。     

陕西省黄河湿地冬季鸟类群落初步研究

1998～2008年,采用直接计数法对陕西省黄河湿地冬季鸟类群落组成、鸟类物种多样性及数量变化进行了调查.在预先设置的5条调查样带中共记录到鸟类14目33科117种.观察结果表明,该地区鸟类多样性指数和均匀度指数分别为4.497和0.654.栖息地可分为人工渔塘、芦苇沼泽、滩涂湿地、农田和人工林5种类型.这些生境中鸟类组成及物种多样性差异均较大,其鸟类多样性指数分别为2.826、3.571、3.202、1.205、2.496,以芦苇沼泽中的鸟类多样性指数最高,滩涂湿地中鸟类数量最多,农田中鸟类优势度最高.通过对该地区鸟类群落组成及多样性分析研究以及黄河湿地冬季鸟类栖息地现状评价,为湿地鸟类资源的保护提供科学依据.     

天童常绿阔叶林样地中优势鸟类食性与采食地点植物的关系

2010年10月至2011年9月,在浙江天童国家森林公园内的天童20 hm2样地中对鸟类食性进行观察,并对鸟类与植物物种间分布关系进行研究。调查观察到鸟类5目12科32种3 130只次,其中优势种类为灰眶雀鹛(Alcippe morrisonia)、红头[长尾]山雀(Aegithalos concinnus)、大山雀(Parus major)、栗背短脚鹎(Hemixos castanonotus)和白头鹎(Pycnonotus sinensis)。采用Sorensen相似性指数和Spearman相关性分析对优势种鸟类与植被分布的关系进行分析,结果显示鸟类分布与植物分布呈对应关系:大山雀和红头[长尾]山雀在同一时期与浙江柿(Diospyros glaucifolia)有相关性,白头鹎同时期与刺毛越橘(Vaccinium trichocladum)和青皮木(Schoepfia jasminodora)相关,栗背短脚鹎在不同时期与同种植物格药柃(Eurya muricata)相关。     

甘肃兴隆山自然保护区森林演替对鸟类群落结构的影响

运用固定面积法调查了青林三个主要演替阶段森林(阔叶林、混交林和针叶林)的鸟类群落结构。结果表明,混交林中鸟类物种数、鸟类物种多样性和种团多样性最高,阔叶林最低。方差分析和聚类分析均表明,三种演替阶段森林的鸟类群落组成差异显著。所记录到的35种鸟类中有11种差异显著。其中,山雀科和科在阔叶林中占优势,而柳莺亚科在混交林和针叶林中占优势。食性种团中,阔叶林以食虫鸟和食果食虫鸟为主;混交林和针叶林均以食虫鸟、食果食虫鸟、食谷鸟和食果鸟为主。鉴于阔叶林和混交林有向顶级群落(针叶林)演替的趋势,建议采取人为干扰来维持三种演替阶段森林的面积,以便从景观水平上保护鸟类物种多样性。     

雅安市区林地鸟类多样性及生态位分析

2009年12月至2010年12月,经过一个年周期的调察与统计,共记录雅安市区林地鸟类79种,隶属于8目32科。通过多样性指数与均匀度指数的测算发现,春秋两季大于夏冬两季,农田类型明显低于次生林、人工林及其他生境。在所有鸟类中,灰喉鸦雀(Paradoxornis alphonsianus)、白头鹎(Pycnonotussinensis)、红头长尾山雀(Aegithalos concinnus)、白颊噪鹛(Garrulax sannio)在不同季节均具有较高的优势度,发冠卷尾(Dicrurus hottentottus)、松鸦(Garrulus glandarius)、大山雀(Parus major)、绿背山雀(P.monticolus)具有最高的生态位宽度值。自20世纪60年代,雅安市区鸟类物种组成及栖息地随城市化进程均发生了较大变化。     

太白山南坡夏秋季鸟类组成

太白山是秦岭山脉的主峰, 生物区系成分复杂。为了研究太白山鸟类区系在过去20年间的变化, 我们于2007年5–7月(夏季)和9–10月(秋季), 根据海拔和典型植被在太白山南坡选定5种生境类型(退耕林、阔叶林、混交林、针叶林和高山灌丛草甸), 并在各种生境中选择样区采用样线法对鸟类组成进行调查。两个季节共观察到鸟类122种, 其中留鸟85种, 夏候鸟31种, 冬候鸟1种, 旅鸟5种。不同的生境类型中优势种和常见种不同, 而且在夏秋两季也有变化。中低海拔退耕林带鸟类物种数最多, 夏季有60种, 优势种为绿背山雀(Parus monticolus)、黄腹山雀(P. venustulus)和冠纹柳莺(Phylloscopus reguloides); 秋季有59种, 优势种为大山雀(Parus major)。中海拔阔叶林带夏季有鸟类40种, 优势种为绿背山雀、黄腹山雀和异色树莺(Cettia flavolivaceus); 秋季37种, 优势种是黄腹山雀、黑冠山雀(Parus rubidiventris)和银脸长尾山雀(Aegithalos fuliginosus)。 中高海拔针阔混交林带夏季有46种, 优势种是黄腰柳莺(Phylloscopus proregulus)、极北柳莺(P. borealis)和黑冠山雀; 秋季有37种, 优势种是黑冠山雀、褐冠山雀(Parus dichrous)和长尾山椒鸟(Pericrocotus ethologus)。高海拔针叶林带夏季有36种, 优势种是黄腰柳莺和黑冠山雀; 秋季有27种, 优势种是血雉(Ithaginis cruentus)和黑冠山雀。高山灌丛草甸带物种最少, 夏秋季都只有7种。各生境中鸟类物种组成的季节周转率随着海拔的升高而下降, 物种丰富度也呈现同样的趋势。太白山南北坡鸟类物种组成有较高的相似性。与20年前相比, 尽管在每种生境类型中优势种和常见种的组成仍相似, 但太白山南北坡的鸟类物种组成有较大的变化。     

江西齐云山自然保护区鸟类区系与多样性分析

2006年11月和2007年2～9月,对齐云山保护区的鸟类进行了本底调查和物种监测,共记录到鸟类257种,隶属于17目54科.其中留鸟120种,候鸟(夏候鸟、冬候鸟和旅鸟)137种;古北界种类97种(37.7%),东洋界种类141种(54.9%),广布种有19种(7.4%);国家重点保护鸟类8科34种;发现江西省新纪录鸟类4种.多样性分析结果显示,该区鸟类群落Shannon-Wiener指数、Pielou指数、和Simpson指数分别为3.875、0.791和0.964.从各生境群落多样性指数看,农田居民区中鸟类群落多样性指数最大,其次是灌草丛和阔叶林,溪流水域的多样性指数最小;优势度指数在不同生境的变化趋势与群落多样性指数相似;灌草丛中鸟类群落均匀度指数最高,阔叶林中的鸟类群落均匀度指数最低.通过与周边包括九连山、井冈山、江西武夷山和广东车八岭4个保护区的鸟类进行物种多样性G-F指数对比分析,得出齐云山鸟类多样性与九连山相当,而高于其他3个保护区.     

长沙黄花国际机场鸟类群落物种多样性分析

为了获得长沙黄花国际机场鸟击防范工作所需的鸟类基础性资料,从2005年9月~2006年8月,通过对机场地区5种生境类型鸟类群落的调查与监测,记录到鸟类112种,属16目32科。其中46种属东洋界种类、45种属古北界种类、21种属广布种;留鸟46种、夏候鸟25种、冬候鸟29种、旅鸟12种。经RB频率指数测算,鸟类群落的优势种为白头鹎(Pycnonotus sinensis)、乌鸫(Turdus merula)和树麻雀(Passer montanus)。按鸟类生境分布系数划分,广布型的鸟类有44种,是该区鸟类群落组成的主体。鸟类群落的Shannon-Weiner物种多样性指数为1.607,均匀性指数为0.784。     

江西老虎脑省级自然保护区鸟类资源调查

2017年11—12月、2018年7—8月、2018年11—12月,在江西老虎脑省级自然保护区开展鸟类资源调查,调查发现该保护区有鸟类17目53科240种。其中,非雀形目16目22科94种,雀形目31科146种。本区鸟类中有留鸟115种,冬候鸟57种,夏候鸟42种,旅鸟26种;古北界87种,广布种22种,东洋界131种。其中,国家重点保护鸟类31种,列入中国红色名录濒危等级(EN)物种有1种,黄胸鹀Emberiza aureola;易危等级(VU)物种有2种,白颈长尾雉Syrmaticus ellioti、白眉山鹧鸪Arborophila gingica;近危等级(NT)物种有19种。中国特有种4种,灰胸竹鸡Bambusicola thoracica、白颈长尾雉、白眉山鹧鸪、黄腹山雀Parus venustulus。多样性分析结果显示,该区鸟类群落Shannon-Wiener指数、Pielou指数分别为4.135、0.778,通过与周围包括武夷山、井冈山、齐云山、九连山4个保护区比较,显示研究区域物种种数较高。     

Agroforestry systems conserve species-rich but modified assemblages of tropical birds and bats

Although an increasing number of studies have shown that diverse, multi-strata agroforestry systems can contribute to the conservation of tropical biodiversity, there is still debate about how the biodiversity within agroforestry systems compares to that of intact forest and alternative land uses. In order to assess the relative importance of agroforestry systems for biodiversity conservation, we characterized bat and bird assemblages occurring in forests, two types of agroforestry systems (cacao and banana) and plantain monocultures in the indigenous reserves of Talamanca, Costa Rica. A total of 2,678 bats of 45 species were captured, and 3,056 birds of 224 species were observed. Agroforestry systems maintained bat assemblages that were as (or more) species-rich, abundant and diverse as forests, had the same basic suite of dominant species, but contained more nectarivorous bats than forests. Agroforestry systems also contained bird assemblages that were as abundant, species-rich and diverse as forests; however the species composition of these assemblages was highly modified, with fewer forest dependent species, more open area species and different dominant species. The plantain monocultures had highly modified and depauperate assemblages of both birds and bats. Across land uses, bird diversity and species richness were more closely correlated with the structural and floristic characteristics than were bats, suggesting potential taxon-specific responses to different land uses. Our results indicate that diverse cacao and banana agroforestry systems contribute to conservation efforts by serving as habitats to high numbers of bird and bat species, including some, but not all, forest-dependent species and species of known conservation concern. However, because the animal assemblages in agroforestry systems differ from those in forests, the maintenance of forests within the agricultural landscape is critical for conserving intact assemblages at the landscape level.     

Poor Prospects for Avian Biodiversity in Amazonian Oil Palm

Expansion of oil palm plantations across the humid tropics has precipitated massive loss of tropical forest habitats and their associated speciose biotas. Oil palm plantation monocultures have been identified as an emerging threat to Amazonian biodiversity, but there are no quantitative studies exploring the impact of these plantations on the biome’s biota. Understanding these impacts is extremely important given the rapid projected expansion of oil palm cultivation in the basin. Here we investigate the biodiversity value of oil palm plantations in comparison with other dominant regional land-uses in Eastern Amazonia. We carried out bird surveys in oil palm plantations of varying ages, primary and secondary forests, and cattle pastures. We found that oil palm plantations retained impoverished avian communities with a similar species composition to pastures and agrarian land-uses and did not offer habitat for most forest-associated species, including restricted range species and species of conservation concern. On the other hand, the forests that the oil palm companies are legally obliged to protect hosted a relatively species-rich community including several globally-threatened bird species. We consider oil palm to be no less detrimental to regional biodiversity than other agricultural land-uses and that political pressure exerted by large landowners to allow oil palm to count as a substitute for native forest vegetation in private landholdings with forest restoration deficits would have dire consequences for regional biodiversity.     

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.     

Bird Communities and Biomass Yields in Potential Bioenergy Grasslands

Demand for bioenergy is increasing, but the ecological consequences of bioenergy crop production on working lands remain unresolved. Corn is currently a dominant bioenergy crop, but perennial grasslands could produce renewable bioenergy resources and enhance biodiversity. Grassland bird populations have declined in recent decades and may particularly benefit from perennial grasslands grown for bioenergy. We asked how breeding bird community assemblages, vegetation characteristics, and biomass yields varied among three types of potential bioenergy grassland fields (grass monocultures, grass-dominated fields, and forb-dominated fields), and assessed tradeoffs between grassland biomass production and bird habitat. We also compared the bird communities in grassland fields to nearby cornfields. Cornfields had few birds compared to perennial grassland fields. Ten bird Species of Greatest Conservation Need (SGCN) were observed in perennial grassland fields. Bird species richness and total bird density increased with forb cover and were greater in forb-dominated fields than grass monocultures. SGCN density declined with increasing vertical vegetation density, indicating that tall, dense grassland fields managed for maximum biomass yield would be of lesser value to imperiled grassland bird species. The proportion of grassland habitat within 1 km of study sites was positively associated with bird species richness and the density of total birds and SGCNs, suggesting that grassland bioenergy fields may be more beneficial for grassland birds if they are established near other grassland parcels. Predicted total bird density peaked below maximum biomass yields and predicted SGCN density was negatively related to biomass yields. Our results indicate that perennial grassland fields could produce bioenergy feedstocks while providing bird habitat. Bioenergy grasslands promote agricultural multifunctionality and conservation of biodiversity in working landscapes.     

Disentangling the relative importance of changes in climate and land-use intensity in driving recent bird population trends

Threats to biodiversity resulting from habitat destruction and deterioration have been documented for many species, whilst climate change is regarded as increasingly impacting upon species' distribution and abundance. However, few studies have disentangled the relative importance of these two drivers in causing recent population declines. We quantify the relative importance of both processes by modelling annual variation in population growth of 18 farmland bird species in the UK as a function of measures of land-use intensity and weather. Modelled together, both had similar explanatory power in accounting for annual fluctuations in population growth. When these models were used to retrodict population trends for each species as a function of annual variation in land-use intensity and weather combined, and separately, retrodictions incorporating land-use intensity were more closely linked to observed population trends than retrodictions based only on weather, and closely matched the UK farmland bird index from 1970 onwards. Despite more stable land-use intensity in recent years, climate change (inferred from weather trends) has not overtaken land-use intensity as the dominant driver of bird populations.     

Presence of Cuckoo reliably indicates high bird diversity: A case study in a farmland area

Here we studied the occurrence of Cuckoo Cuculus canorus and top predators as indicators of biodiversity in agro ecosystems of Western Poland, to identify local hotspots. Bird species richness and land-use diversity were used as measures of biodiversity. The relationship between the presence of Cuckoos and four avian top predators with biodiversity measures were examined using Generalized Linear Mixed Models.Cuckoos were mainly distributed on sites with greater species richness, but were absent from the low species richness sites, while the top predators were distributed uniformly. The performance of the best models using the presence of Cuckoo was 27% higher than the best models using top predators. Our results highlight the predictive capacity of Cuckoos as an indicator of bird species richness than top predators and the usefulness of this species in biodiversity studies. The cookoo is charismatic, widespread across the main types of landscapes, and is easy to detect from its song. Importantly, our findings propose that cookoo can be used as effective and cheap tool to monitor the high bird diversity in different European countries.     

Evaluating the effectiveness of overstory cover as a surrogate for bird community diversity and population trends

Landscape features are often used as surrogates for biodiversity. While landscape features may perform well as surrogates for coarse metrics of biodiversity such as species richness, their value for monitoring population trends in individual species is virtually unexplored. We compared the performance of a proposed habitat surrogate for birds, percentage cover of vegetation overstory, for two distinct aspects of bird assemblages: community diversity (i.e. species richness) and population trends. We used four different long-term studies of open woodland habitats to test the consistency of the relationship between overstory percentage cover and bird species richness across a large spatial extent (>1000 km) in Australia. We then identified twelve bird species with long-term time-series data to test the relationship between change in overstory cover and populations trends. We found percentage cover performed consistently as a surrogate for species richness in three of the four sites. However, there was no clear pattern in the performance of change in percentage cover as a surrogate for population trends. Four bird species exhibited a significant relationship with change in percentage overstory cover in one study, but this was not found across multiple studies. These results demonstrate a lack of consistency in the relationship between change in overstory cover and population trends among bird species, both within and between geographic regions. Our study demonstrates that biodiversity surrogates representing community-level metrics may be consistent across regions, but provide only limited information about individual species population trends. Understanding the limitations of the information provided by a biodiversity surrogate can inform the appropriate context for its application.     

Satellite image texture and a vegetation index predict avian biodiversity in the Chihuahuan Desert of New Mexico

Predicting broad-scale patterns of biodiversity is challenging, particularly in ecosystems where traditional methods of quantifying habitat structure fail to capture subtle but potentially important variation within habitat types. With the unprecedented rate at which global biodiversity is declining, there is a strong need for improvement in methods for discerning broad-scale differences in habitat quality. Here, we test the importance of habitat structure (i.e. fine-scale spatial variability in plant growth forms) and plant productivity (i.e. amount of green biomass) for predicting avian biodiversity. We used image texture (i.e. a surrogate for habitat structure) and vegetation indices (i.e., surrogates for plant productivity) derived from Landsat Thematic Mapper (TM) data for predicting bird species richness patterns in the northern Chihuahuan Desert of New Mexico. Bird species richness was summarized for forty-two 108 ha plots in the McGregor Range of Fort Bliss Military Reserve between 1996 and 1998. Six Landsat TM bands and the normalized difference vegetation index (NDVI) were used to calculate first-order and second-order image textures measures. The relationship between bird species richness versus image texture and productivity (mean NDVI) was assessed using Bayesian model averaging. The predictive ability of the models was evaluated using leave-one-out cross-validation. Texture of NDVI predicted bird species richness better than texture of individual Landsat TM bands and accounted for up to 82.3% of the variability in species richness. Combining habitat structure and productivity measures accounted for up to 87.4% of the variability in bird species richness. Our results highlight that texture measures from Landsat TM imagery were useful for predicting patterns of bird species richness in semi-arid ecosystems and that image texture is a promising tool when assessing broad-scale patterns of biodiversity using remotely sensed data.     

An assessment of the efficiency of protection status through determinations of biodiversity hotspots based on endemic bird species,Taiwan

Evaluations of species richness patterns have been performed at diverse scales, and biodiversity hotspots, especially endemism hotspots, have received much attention in conservation biology. We estimated the distributions of endemic bird species based on a 12-yr avian inventory project in Taiwan, identified biodiversity hotspots of endemism on a regional scale based on predictions from the ensemble forecasting framework and frequency histogram approach, and assessed the efficiency of protected areas. The results indicated that the predicted endemism hotspots were mostly located in mid- and high-elevation areas along the Central Mountain Range of Taiwan. An observed endemism hotspot was defined as one in which at least five of Taiwan's 17 endemic bird species were present. This criterion was used because the 5% of the sampled grid squares that were the richest in endemic bird species all had 5 endemic bird species or more. Seventy to seventy-one percent of the observed biodiversity hotspots matched the predicted biodiversity hotspots. This outcome was obtained whether the richness biodiversity in a grid square was based on summed predicted probability or summed predicted richness. The majority of the protected areas for these Taiwanese endemic bird species were national parks, protecting 24.1% of the predicted hotspot areas, whereas nature reserves and wildlife refuges protected less than 7%. Most of the predicted endemism hotspots were not adequately protected. We conclude that the ensemble forecasting framework and the frequency histogram approach are useful for selecting critical habitats and biodiversity hotspots for endemic species and for appraising the efficiency of the protection status provided by governments.     

Bird community patterns in response to the island features of urban woodlots in eastern China

Many studies have demonstrated the changes in the spatial patterns of plant and animal communities with respect to habitat fragmentation.Insular communities tend to exhibit some special patterns in connection with the characteristics of island habitats.In this paper,the relationships between richness,assemblage,and abundance of bird communities with respect to island features were analyzed in 20 urban woodlots in Hangzhou,China.Field investigations of bird communities,using the line transect method,were conducted from January to December,1997.Each woodlot was surveyed 16 times during the year.Results indicated that bird richness was higher,per unit area,in the smaller woodlots than the larger ones,and overall bird density decreased with the increase in the size of woodlot.However,the evenness of species abundance increased with the area,and small woodlots were usually dominated by higher density species and large woodlots by medium density species.Most species occurring in the small woodlots also occurred in larger woodlots.Also,bird communities among urban woodlots showed a nestedness pattern in assemblage.These patterns implied that the main impacts of woodland habitat fragmentation are:(1) species are constricted and thus species number will increase at a given sample size;(2) as surface area decreases,the proportion of forest edge species as to interior species will increase;(3)community abundance will therefore increase per unit area but most individuals will be from a few dominant species;and (4) overall species diversity will decrease at a habitat level as well as at a region level.These patterns of community in response to the island features were therefore summarized as "island effects in community".The underlying processes of such observations were also examined in this paper.Woodlot area,edge ratio,isolation,and habitat nestedness were considered as the important factors forming the island effects in community.High heterogeneity between habitats usually contributed most to the maintenance of regional biodiversity,especially in urban woodlots.