A growing captive population erodes the wild Red-crowned Cranes(Grus japonensis) in China

Background: The Red-crowned Crane(Grus japonensis) is an endangered bird species and while the wild population continues to decrease in China, the captive population has dramatically increased over the last two decades. We hypothesized that some of the captive Red-crowned Cranes originated from the wild and that a growing captive population is eroding the wild population in China.Methods: We surveyed the size of the population and determined the average annual growth rate, reproductive success rate and mortality rate of captive Red-crowned Cranes in 2013 in China. We assessed this erosion effect through mathematical models, in which the size of the captive Red-crowned Crane population was determined from the annual growth rate, the reproductive success rate and the rate of mortality.Results: We found there were a total of 1520 captive Red-crowned Cranes in 2013 in China, with an average annual gro-wth rate of 7.46%, a reproductive success rate of 9.17% and a mortality rate of 3.6%. We found that approximately 1027 supplementary Red-crowned Cranes per year and a total of 244, over the 14 year period from 1999 to 2013, were needed to account for the growing captive population in China.Conclusion: We conclude that the 244 birds probably came from the wild by taking eggs and capturing juveniles or adults and hence accepted the hypothesis. Perhaps more surprisingly, our annual estimate of the number of supplementary Red-crowned Cranes in captive populations is very conservative, with the erosion effect substantially underestimated, because the total number of captive Red-crowned Cranes in 2013 was underestimated, with the annual reproductive success rate in zoos overestimated. The existence of an erosion effect provides a new perspective for the interpretation of why the Red-crowned Crane population in the wild continues to decrease. In our opinion, it is important to understand the consequences of this erosion effect on the management and conservation of this endangered bird species in China.

Avian orientation: multi-cue integration and calibration of compass systems

Migratory birds are known to use a number of different orientation cues to determine and maintain the direction of their movements. They are able to use at least three different sources of compass information, including solar, stellar and geomagnetic cues. However, little is known about how these cues are calibrated into uniform reference direction information, while the hierarchy of these cues remains controversial. In recent studies, researchers suggest that avian migrants calibrate their geomagnetic compass on sunset cues, whereas others fail to find such patterns and insist on the prevalence of the magnetic compass. We carefully reviewed the existing literature and suggest that the conflicting results reported by different authors are due to genuine variation among species and propose hypotheses to explain this variation.

Avian Research

Aims and Scope Avian Research is an open access,peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world.It aims to report the latest and most significant progress in ornithology and to encourage exchange of ideas among international ornithologists.As an Open Access journal,

The rediscovery of Strix butleri(Hume,1878)in Oman and Iran,with molecular resolution of the identity of Strix omanensis Robb,van den Berg and Constantine,2013

Background:Many species of owls(Strigidae) represent cryptic species and their taxonomic study is in flux.In recent years,two new species of owls of the genus Strix have been described from the Middle East by different research teams.It has been suggested that one of these species,S.omanensis,is not a valid species but taxonomic compari?sons have been hampered by the lack of voucher specimens of S.omanensis,and the poor state of the holotype of S.butleri.Methods:Here we use new DNA sequence data to clarify the taxonomy and nomenclature of the S.butleri complex.We also report the capture of a single S.butleri sensu stricto in Mashhad,Iran.Results:A cytochrome b sequence of S.omanensis was found to be identical to that of the holotype of S.butleri,indicating that the name S.omanensis is best regarded as a junior synonym of S.butleri.The identity of the S.butleri captured in Mashhad,Iran,was confirmed using DNA sequence data.This represents a major(1300 km) range exten?sion of this species.Conclusions:The population discovered in Oman in 2013 and originally named ‘S.omanensis' actually represents the rediscovery of S.butleri,which was known from a single specimen and had not been recorded since 1878.The range of S.butleri extends into northeast Iran.Our study augments the body of evidence for the recognition of S.butleri and S.hadorami as separate species and highlights the importance of using multiple evidence to study cryptic owl species.

Nest predators, nest-site selection and nest success of the Emei Shan Liocichla(Liocichla omeiensis), a vulnerable babbler endemic to southwestern China

Background: The Emei Shan Liocichla(Liocichla omeiensis) is a globally vulnerable babbler, endemic to southwestern China. We investigated its nest predators, nest-site selection and nest success at the Laojunshan National Nature Reserve in Sichuan, China in order to identify the precise nesting-habitat requirements of the species, and to test whether the nest-site-selection cues, preferred by the Emei Shan Liocichla, are positively associated with nest success.Methods: We used infrared cameras to determine nest predators. We compared the microhabitat attributes between nest and random sites, as well as successful and failed nests. We used Binary Logistic Regression to determine the most important variables affecting nest-site selection of the Emei Shan Liocichla. We used the nest survival analysis in Program MARK to estimate daily nest survival rates(DSR). Nest success was calculated using the Mayfield method.Results: In total 56 nests were found. The DSR for all nests that contained at least one egg was 0.9564 ± 0.0091(95 % CI 0.9346–0.9711)(n = 40), while the total nest success was 27.5 %. We identified four categories of predators in 10 nest predation events, i.e. squirrels(n = 5), snakes(n = 3), raptors(n = 1) and wasps(n = 1). We found that:(1) nest predation was the primary reason for nest failure of the Emei Shan Liocichla,(2) tree cover, bamboo cover, liana abundance and distance to forest edge or gap were the most important variables affecting nest-site selection of this species, and(3) the nest-site-selection variables we measured appeared not to be positively associated with nest success.Conclusions: Our findings suggest that the Emei Shan Liocichla tended to select nest sites near forest edges or gaps with good concealment and that nest-site selection by this species was nonrandom but not necessarily adaptive. Reducing forest-edge development and protecting bamboo stands should be effective for conservation of this species.

Behaviors of the Oriental White Stork (Ciconia boyciana) in a semi-natural enclosure

Environmental factors affect animal behavior in a variety of ways. Compared to animals in the wild, captive animals are kept in narrow enclosures, suffer higher densities and are more intensely affected by human activities. Therefore, behavioral elasticity is likely modified to some extent in captive animals, which may negatively affect the possibility of successful release of endangered species in the wild. In our study we investigated the behaviors of the Oriental White Stork (Ciconia boyciana) in a semi-natural enclosure from 15 October 2005 to 8 September 2006 in Hefei Wildlife Park, China. The behavioral data were collected by instantaneous and scan sampling methods, and we analyzed the relationships between environmental factors and their behaviors. The amounts of time spent on maintenance behavior (foraging and moving) were at similar levels for birds reproducing multibroods (Group 1), birds reproducing one brood (Group 2) and birds without reproduction (Group 3). On the other hand, the amount of time spent on elastic behavior (defensive, breeding and preening) for Group 3 was lower than that for Groups 1 and 2. The behavioral pattern of the storks exhibited marked seasonal changes, which may be a function of ambient temperature, human disturbanc, and the length of daylight, but not of wind intensity. Our results provide basic data for future conser- vation measures of this endangered species.

Jankowski’s Bunting (Emberiza jankowskii): current status and conservation

Jankowski’s Bunting (Emberiza jankowskii) is a small bird with narrow distribution ranges. It has experienced a drastic population decline during recent years and vanished from most of its historic breeding sites. It has been recently up-graded as Endangered in the IUCN Red List of globally threatened species. By integrating unpublished data of field surveys conducted by us and published information on the species, we provide information on the status of distribution, breeding biology of the remaining population at the Dagang Forest Farm, population trends at currently known breeding sites, selection of breeding habitats and threats faced by the Jankowski’s Bunting. In light of its current status we also suggest ways and future research work related to protecting this bird species.

Cross-species amplification and characterization of microsatellite DNA loci from Gallus gallus in Bambusicola thoracica

The Chinese Bamboo Partridge(Bambusicola thoracica) is a gamebird endemic to China.Ten polymorphic microsatellite(simple sequence repeat) markers were obtained through cross-species amplification for this partridge from its relative species Gallus gallus.The number of alleles per locus varied from 4 to 13.The observed heterozygosity ranged from 0.1220 to 1.0000 and the expected heterozygosity from 0.1183 to 0.8898.Four microsatellite loci showed significant differences from the Hardy-Weinberg equilibrium.These polymorphic loci provide a valuable tool for the investigation of the phylogeography and conservation genetics of this partridge.

Egg-spot matching in common cuckoo parasitism of the oriental reed warbler: effects of host nest availability and egg rejection

Background: The success of cuckoo parasitism is thought to depend largely on the extent of egg matching between cuckoo and host eggs, since poor-matching cuckoo egg would lead to more frequent egg rejection by the host. In this study, we investigated how egg-spot matching between the Common Cuckoo(Cuculus canorus) and its host, the Oriental Reed Warbler(Acrocephalus orientalis) is affected by the local parasitism rate, nest availability in breeding synchronization and egg rejection.Methods: We used the paired design of parasitized and their nearest non-parasitized nests where breeding occurred simultaneously to compare egg-spot matching. The image analysis was used to compare four eggshell pattern variables, namely spot size, density, coverage on the different areas of egg surface, and the distribution on the whole egg surface. Egg recognition experiments were conducted to test the effect of egg spots on egg rejection by the host.Results: Our results show that much better matching in almost all spot parameters tested on the side of the egg and the spot distribution on the whole egg occurred in parasitized nests than in non-parasitized nests. Matching of spot density between cuckoo and host eggs in parasitized nests increased with the synchronization between temporal availability of nests and the egg-laying period of female cuckoos. Egg recognition experiments in which the warbler eggs were deliberately painted with extra spots led to a significantly higher egg rejection rate(78.3%) than of unpainted eggs.Conclusion: Our data suggest that both the high temporal encounter rate between cuckoo and warbler nests as well as the high egg rejection ability of the host are important factors for egg-spot matching of the cuckoos.

Ardeid nesting colonies in central Guizhou,southwestern China

A survey of Ardeid nesting colonies in central Guizhou,southwestern China in May 2006,which covered about one-third of the area of this province,recorded a total of 1587 nests of five species,i.e.,Little Egret (Egretta garzetta),Cattle Egret (Bubulcus ibis),Chinese Pond Heron (Ardeola bacchus),Black-crowned Night Heron (Nycticorax nycticorax) and Grey Heron (Ardea cinerea) at 11 nesting colonies.The largest colonies were recorded at Fengyunyan and Yanfu resorts,the smallest one at Luobolin.The Little Egret was the dominant nesting species (49.7% of the total number of nests) and the Grey Heron was the least abundant (0.1%).All nesting colonies were located in the northern and central parts of Guizhou;no colonies were found in the Leigongshan area,the southern part of this province.The distribution of nesting colonies in central Guizhou appears to be affected by the relative composition of winter (wheat and vegetable) and summer (rice) crops during the breeding season (between late March and June).No colonies were found around farmlands with winter crops and most colonies were situated around rice paddies.The farmland use pattern is affected by rainfall.The summer crop is delayed if the rainy season starts late and the rainfall is light.Priority for conservation of the Ardeids in central Guizhou should be given to the larger colonies i.e.,Yanfu and Fengyunyan resorts.

Identification of habitat requirements of farmland birds based on a hierarchical structured monitoring scheme

Agricultural landscapes are essential for the conservation of biodiversity. Nevertheless, a negative trend continues to be observed in many rural areas for the most prominent indicator species group, the farmland birds. However, clear cause-effect relationships are rarely reported and sometimes difficult to deduce, especially from monitoring data which are based only on the detection of species and counts of the numbers of individuals. Because the identification of habitat preferences is a precondition for farmland bird biodiversity conservation efforts, a monitoring scheme for the simultaneous collection and analysis of bird and land use data was developed and tested. In order to assign the occurrence of bird species to land characteristics at various spatial scales and different land use and crop types, we applied a hierarchical structured sampling design. The spatial scales were ‘agricultural landscape', ‘agricultural landscape types', ‘field crops and other habitats' and ‘vegetation structures'. These scales were integrated with a novel concept, the ‘habitat matrix'(HM). This method was applied to farmland breeding bird abundances on 29 plots, each 1 km2 in size, by the use of the territory mapping method. The same plots were enlarged by a 100 m buffer and the sizes and location of habitats documented. Vegetation height, coverage and density were also recorded for all crop fields in the study area. We propose that this monitoring method facilitates the identification of scale dependent relationships between farmland bird habitat characteristics and bird abundance. This is demonstrated by the farmland bird species Corn Bunting(Emberiza calandra), Skylark(Alauda arvensis), and Whinchat(Saxicola rubetra). The breeding territories of these species reveal large differences within the various spatial scales ‘agricultural landscape', ‘agricultural landscape types' and ‘field crops'. Throughout the breeding season the abundances varied, dependent on the field crop and the development of vegetation structures(height, coverage, and density). HM-analysis led to the identification of specific habitat configurations preferred by individual bird species within the agricultural landscape. These findings indicate that the methodology has the potential to design monitoring schemes for the identification of cause-and-effects of landscape configuration, land use and land use changes on the habitat suitability and abundance of farmland birds.

Home range and habitat composition of male Reeves's Pheasants in an agricultural-forest plantation landscape in central China:a preliminary report

We present a preliminary examination of the home range and habitat use of male Reeves's Pheasants (Syrmaticus reevesii) in an agricultural-forest plantation landscape on the Xianjuding Forest Farm, Hubei Province, central China. Fieldwork was carried out from March to August in 2003. The home range of males averaged 33.17 ± 12.55 ha by MCP (minimum convex polygon) and 21.05 ± 5.61 ha by a 95% fixed kernel estimator. The core area by a 60% fixed kernel estimator was 3.92 ± 0.27 ha. We did not detect significant seasonal variations in home range, core area and movement in this farm. Chinese fir (Cunninghamia lanceolata) plantations were the dominant habitat type within the home ranges and core areas. The males used their habitat non-randomly in spring and summer, preferred the fir plantations and avoided broadleaf forests in both seasons. In addition, the males used shrubs less than were available in the spring. The vegetation structure of different habitats may be the leading factor affecting the use of the habitats.

Muscle architecture of the forelimb of the Golden Pheasant(Chrysolophus pictus)(Aves: Phasianidae)and its implications for functional capacity in flight

Background: Flight is the central avian adaptation in evolution. Wing muscles form an important anatomical basis for avian flight, affecting wing performance and determine modes of flight. However, the roles of distal muscles in adjusting the wing, as well as their functional specializations, remain largely unknown. The importance of muscle fiber architecture has long been recognized. In this study, we provide quantitative anatomical data on the muscle architecture of the forelimb of the Golden Pheasant(Chrysolophus pictus), with an emphasis on brachial,antebrachial and manual segments.Methods: The forelimbs of five Golden Pheasants were dissected and detailed measurements of all muscles were made, including muscle mass, muscle belly length, fascicle length. From these values, muscle volume, physiological cross-sectional area(PCSA) and maximum isometric force were derived.Results: General trends such as the distribution of muscle mass, fascicle length and the ratio of tendon length/belly length are revealed. Comparing PCSAs between antebrachial depressors and elevators and between intrinsics of the alular digit and major digit yielded significant differences(p < 0.05). Pronounced development of the antebrachial depressors suggests that ventral rotation of the distal half of the wing is a pivotal factor in shape change and orientation modulation. Large PCSAs in tandem with the force generation capability of the major digit intrinsics may help stabilize the digits while enhancing support of the primary feathers. The architectural properties of the alular digit confirm that alular adjustment is essential to rapid adduction and abduction.Conclusions: These observations illustrate the underlying structural basis for the functional capacities of the distal forelimb muscles and may provide additional information useful in further biomechanical and in vivo investigations.

Effect of colonial breeding of Chinese Egret(Egretta eulophotes) on the heavy metal accumulation in heronry soil

We measured the concentrations of heavy metal elements,i.e.,V,Cr,Mn,Ni,Cu,Zn,Cd,Se and Pb and the semi-metal element As in feces of Chinese Egret(Egretta eulophotes)on Caiyu Island in Zhangpu County,Fujian Province,China using inductively coupled plasma-mass spectrometry(ICP-MS) and compared the differences between the topsoil of their nesting and non-nesting areas before and after breeding.The results show that no Se and Cd was detected in any of the samples,including feces and soil,while heavy metal concentrations in the non-nesting soil were not significantly different before and after breeding(p > 0.05),but the differences in concentrations of Zn and Pb in the nesting soil were highly significant before and after breeding(p < 0.01).A comparison of the concentrations of the elements in the nesting and non-nesting soils also reveals that before breeding,the concentration of Zn in these two soils were significantly different(p < 0.01).After breeding,concentrations of Cu,Zn,As and Pb in the nesting and non-nesting soil were significantly different(p < 0.01) while V and Ni concentrations showed merely significant differences(p < 0.05).These findings indicate that the colonial breeding activities of E.eulophotes play an important role in the transfer of heavy metals between wetland and island eco-systems and that such activities may,over time,result in heavy metal contamination of the heronry soil on the island.

Experimental evidence for ovarian hypofunction in sparrow hybrids

Background: Postzygotic isolation in the form of reduced viability and/or fertility of hybrids may help maintain species boundaries in the face of interspecific gene flow. Past hybridization events between house sparrows(Passer domesticus) and Spanish sparrows(P. hispaniolensis) have given rise to a homoploid hybrid species, the Italian sparrow(P. italiae). Although genetic incompatibilities are known to isolate these three species, the biological consequences of these incompatibilities are still unknown in early generation hybrids.Methods: We investigated whether F1 hybrids between house and Spanish sparrows experience reduced viability or fertility. More specifically, we generated hybrids through controlled crosses in aviaries, and compared ovaries of female hybrids with female of pure?species sparrows.Results: We found that overall, hybrid ovaries were underdeveloped and that half of all female hybrids exhibited symptoms of ovarian hypofunction(ovarian atrophy and complete absence of developed follicles).Conclusions: Fertility in hybrids is a common consequence or post?zygotic barriers between species. We discuss these results in light of previous findings on genetic incompatibilities between the parent species and the potential role of incompatibilities in hybrid speciation, a rare evolutionary process in birds.

Temporal-spatial patterns of intestinal parasites of the Hooded Crane(Grus monacha) wintering in lakes of the middle and lower Yangtze River floodplain

Background: Parasites have adverse effects on the life and survival of many migratory waterbirds, especially birds on the endangered species list. Hooded Cranes are large migratory colonial waterbirds wintering in wetlands,which are prone to parasite infection, thus monitoring the diversity of parasites is important for sound wetland management and protection of this species.Methods: From November 2012 to April 2013, we collected 821 fresh faecal samples from the three lakes(Poyang,Caizi and Shengjin Lake) in the lower and middle Yangtze River floodplain, and detected with saturated brine floating and centrifugal sedimentation methods. Parasite eggs were quantified with a modified Mc Master's counting method.Results: In this study, 11 species of parasites were discovered, i.e., two coccidium(Eimeria gruis, E. reichenowi), five nematodes(Capillaria sp., Strongyloides sp., Ascaridia sp., Trichostrongylus sp., Ancylostomatidae), three trematodes(Echinostoma sp., Echinochasmus sp., Fasciolopsis sp.) and one cestode(Hymenolepis sp.). About 57.7% of the faecal samples showed parasitic infection. All species of parasites were found at the three sites except Hymenolepis which was not found at Poyang Lake. While most samples were affected by only one or two species of parasites, infection by Eimeria spp. was the most common(53.1%). From One-Way ANOVA analysis of the three lakes, parasite species richness index(p = 0.656), diversity index(p = 0.598) and evenness index(p = 0.612) showed no significant difference. According to the statistical analysis of our data, there were no significant difference in parasite species richness index(p = 0.678) and evenness index(p = 0.238) between wintering periods, but a strong difference in diversity index(p < 0.05).Conclusions: Our study suggests that in the wintering Hooded Crane populations, parasite diversity is more sensitive to changes in the overwintering periods than to locations. This also indicates that with the limitations of migration distance, the parasites may not form the differentiation in Hooded Crane populations of the three lakes.

Suitable distance to observe Red-crowned Cranes:a note on the observer effect

In order to assess the effect of the observer distance on the behavior of Red-crowned Cranes (Grus japonensis),we studied their time budgets with a gradient of observer distances in Yancheng,China from December 2008 to March 2009.Observer distance was classified into four levels,i.e.,＜ 200 m,200-300 m,300-400 m and ＞ 400 m.The results indicated that cranes increased their vigilance when the observer was less than 300 m away.A safe distance for the observer was often as far as or more than 300 m.Cranes increased scan frequency when observers were within 200 m,whereas they prolonged the duration of their scan when observers were between 200 m and 300 m away,indicating two distinct vigilant strategies,given the observer distance.We suggest an observer distance of at least 300 m,in order to minimize the observer effect.

Introduction of WPA-China

WPA-China was established in 1991 as a chapter of World Pheasants Association (WPA)-International with Prof. Guangmei ZHENG now as its president. WPA-China has about 100 members from all over the country, mostly researchers from universities,

Monitoring population dynamics of the migratory Red-crowned Crane (Grus japonensis) at Shuangtaihekou National Nature Reserve,northeastern China,from 1991 to 2012

We studied migratory Red-crowned cranes from 1991-2012 in order to track population dynamics and trends for these cranes over time at Shuangtaihekou,northeastern China.Our results show that the earliest arrival date of the Red-crowned Crane (Grus japonensis) was usually around 1 March in the spring and the latest departure date of the cranes around 8 November.The peak period for the number of cranes observed in the spring was 10-20 March over these 22 years.The staging period in the spring is about 25 days.Comparing the highest number of Red-crowned cranes observed in the spring,the migratory population was around 400 birds in the 1990s,then,increased to over 800 birds in 2000.For a short while,the population maintained itself around 600-800 birds.After that,the population started to decline,until during the most recent years,we observed around 400 birds at peak times of each season.Our results match a similar population change pattern observed in the wintering area for a western population,which has been declining since 2000.There is an urgent need to reinforce protection and management,as well as to maintain and improve the quality of their habitats.