Habitat utilization and resource partitioning of wintering Hooded Cranes and three goose species at Shengjin Lake

The loss and degradation of wetlands have adversely affected waterbirds, which depend on wetland habitats. Interspecific competition has an important effect on habitat utilization of wintering waterbirds. Resource utilization, including partitioning, in degraded wetlands has become a hot issue in ecological studies of wintering waterbirds. In order to have an insight into the habitat utilization and resource partitioning between a Hooded Crane(Grus monacha) population and the guild of three goose species, i.e., Anser fabalis, A. albifrons and A. erythropus wintering in lake wetlands, we carried out a study at Shengjin Lake National Nature Reserve from November 2011 to April 2012. We surveyed the Hooded Cranes and goose guild foraging in various habitats during the wintering periods with a combined method of fixed route searching and fixed site observations. Resource partitioning was studied by means of calculating habitat utilization rates and the width and overlap of spatial niches. The results showed that the habitat utilization rate and the width of spatial niches of the Hooded Crane population and goose guild shifted with the season. The habitat utilization rates of the cranes in grasslands were high at all three wintering stages. The habitat utilization rates were 0.454, 0.435 and 0.959 respectively for the Hooded Cranes and 0.627, 0.491 and 0.616 for the goose guild. This suggests that the overlap in grasslands was higher between cranes and goose guild. Most habitats were accessible at the middle stage, so the width of the spatial niche of the cranes(1.099) and goose guild(1.133) both reached their peak at this stage. The greatest niche overlap was 0.914 for these two groups at the late stage, followed by 0.906 at the middle stage and the smallest was 0.854 at the early stage. Ecological response to the changes in habitats of wintering waterbirds was clearly shown in the dynamic variations of the niche of both the Hooded Cranes and the three goose species. Coexistence among waterbirds was achieved by regulation of niche width to reduce niche overlap and relieve interspecific resource partitioning.

Study on Biological Habits and Control of Scirothrips dorsalis Hood on Mangoes

[Objective] This study aimed to explore the biological habits of Scirothrips dorsalis Hood and methods for controlling this pest. [Method] From 2009 to 2011, the biological habits of Scirothrips dorsalis Hood and the regularity of its occurrence on mangoes were investigated at the experimental base of the Institute of Tropical and Subtropical Cash Crops, Yunnan Academy of Agricultural Sciences and Shuanghongqiao Mango Orchard in Baoshan, Yunnan Province. In addition, a field trial on the effects of four medicaments on controlling this pest was also conducted. [Result] The result showed that Scirothrips dorsalis Hood completed 10-12 genera- tions per year in Baoshan area, and the peak period of its incidence was from February to April. The results of the pest control testing showed that at 0.05 level, there were significant differences of effect on pest controlling among the treatments I, II and IV, and the treatment III showed significant differences of controlling effect with the treatment IV, while no significant differences with either the treatment I or the treatment II; at 0.01 level, there was no significant difference among the treat- ments I, II and III, while all the three treatments showed significant differences with treatment IV. [Conclusion] This study revealed that the occurrence and the severity of Scirothrips dorsalis Hood on mangoes in Baoshan, Yunnan Province. In addition, pesticides with certain efficacy on controlling Scirothrips dorsalis Hood were screened, which provides more options for fruit growers to control this pest on mangoes.

Hood联合Clipless技术对机器人辅助前列腺癌根治术后患者尿控及勃起功能的影响

目的探讨Hood联合无血管夹(Clipless)技术对机器人辅助前列腺癌根治术(RARP)后患者尿控及勃起功能恢复的影响。方法回顾性分析2020年6月至2021年6月接受Hood联合Clipless技术RARP患者的临床资料,共纳入37例术前国际勃起功能指数(IIEF-5)评分>21分的患者。患者年龄平均58.9岁(45~66岁),术前初诊平均t PSA13.24ng/ml(2.7~23.0ng/ml)。所有患者术前经会阴前列腺MRI/超声融合穿刺明确病理诊断,Gleason评分平均7.3分(6~8分)。所有患者术前均行多参数MRI检查及全身核素扫描明确肿瘤分期,术前临床分期为T_(2a)期10例、T_(2b)期8例、T_(2c)期19例。记录患者手术参数及术后3、6、9和12个月的IIEF-5评分。结果37例患者术中平均出血量56.5ml(20~110ml),无输血及切缘阳性病例;患者术后平均住院时间7.3d(5~8d),术后1周拔除尿管,34例患者拔除尿管24h内恢复尿控;术后3、6、9和12个月分别有48.7%、75.7%、86.5%和91.9%的患者恢复勃起功能,患者IIEF-5评分>21分。术后12个月随访无生化复发。结论Hood联合Clipless技术RARP安全可行,在游离前列腺侧蒂时采用Clipless技术,不增加手术出血量及切缘阳性率,术后患者即刻尿控及勃起功能恢复较好。

Stokes方程组Hood-Taylor元的分裂外推

考虑拟一致矩形网格上Stokes方程组Hood-Taylor元的多参数渐近误差展开和分裂外推。在每个单元上用Bramble-Hilbert引理确定微分方程精确解与有限元插值之间积分式的主项。由连续性条件相邻两个单元上其主项的某些部分可以相互抵消,经求和后,得到整个求解区域上的主项。对该主项引入辅助问题并利用Stokes问题解的正则性理论给出精确解与有限元插值间的一个误差渐近展开式。有限元解经插值后处理和分裂外推后,与通常的误差估计相比,收敛速度提高了一阶。

HOOD方法与形式化技术的集成研究

ＨＯＯＤ是由欧洲ＥＳＡ公司开发的一种面向对象软件结构设计方法，它使用图形、结构化英语和Ａｄａ伪码来描述系统的设计规约。本文首先概述了ＨＯＯＤ方法的基本概念和对它进行的改进，然后提出了一种集成ＨＯＯＤ和形式化技术的方法，借助该方法可以获得更为严格的软件设计规约，最后简要介绍了其机器支撑系统。

层次式面向对象设计方法HOOD的研究与改进

本文详细介绍了层次式面向对象设计方法HOOD的基本概念和设计过程，以及其图形和文本描述语言，然后与其他面向对象设计方法进行了比较，指出了HOOD方法的优点与不足，进而，提出了一种改进HOOD的方案。

定常Navier-Stokes方程的三个梯度-散度稳定化Taylor-Hood有限元

本文针对定常Navier-Stokes方程给出了三种梯度-散度稳定化Taylor-Hood元.为了克服Taylor-Hood混合有限元离散迭代解不满足质量守恒律的问题,本文在已有的三种迭代格式上增加了梯度-散度稳定项,以便在得到连续离散速度和压力解的同时使离散速度解满足质量守恒律.在强唯一性条件下,本文证明了这三种梯度-散度稳定化Taylor-Hood元迭代格式的离散解在一定迭代次数下逼近Scott-Vogelius混合有限元离散解.数值实验验证了本文的结果.

The effects of food abundance and disturbance on foraging flock patterns of the wintering Hooded Crane(Grus monacha)

Background:Food abundance and availability affect flock patterns of foraging birds.Cost and risk tradeoffs are especially critical for flocks of wintering waterbirds foraging in lake wetlands.Waterbirds losing suitable habitats face insufficient food supplies and high levels of disturbance,affecting their foraging activities.Our objective was to study the effects of food abundance and disturbances on flock size and the structure of Hooded Crane flocks wintering at Shengjin Lake and,as well,to understand the response of wintering waterbirds to habitat degradation for future management decisions and protection of the population.Methods:We investigated food abundance,disturbances and flock foraging activities of the wintering Hooded Crane in several foraging habitats of Shengjin Lake from November 2013 to April 2014.Flock size and structure were observed by scan sampling.Data on food abundance and disturbances were collected by sampling.Flock size and structure were compared among three wintering stages.The relationship between food resources,disturbances and flock size were illustrated using a generalized linear model.Results:In the early and middle wintering periods,the Hooded Crane used paddy fields as its major foraging habitat,where the number of foraging birds and flocks were the highest.During the late period,the cranes took to meadows as their major foraging habitat.The variation among foraging flock was mainly embodied in the size of the flocks,while the age composition of these flocks did not change perceptibly.Family flocks were notably different from flock groups in size and age composition.The results of a generalized linear model showed that the food abundance had a marked effect on foraging flock size and age composition,while disturbances had a significant effect only on flock size.From our analysis,it appeared that the combined effect of the two variables was significant on the size of the foraging flock,but had less impact on age composition.Conclusions:Food abundance and disturbances affected the flock size of the Hooded Crane.With abundant food and high disturbances,flock sizes increased owing to cooperation in foraging.To avoid competition and maximize foraging benefits,flock size reduces with an abundance of food but low disturbance.By trading off risks and costs,the cranes showed flexible flock distributions and a variety of foraging strategies to maximize benefits and to improve their fitness.

Optimum Tilt Angle of Flow Guide in Steam Turbine Exhaust Hood Considering the Effect of Last Stage Flow Field

Abstract Heat transfer and vacuum in condenser are influenced by the aerodynamic performance of steam tur- bine exhaust hood. The current research on exhaust hood is mainly focused on analyzing flow loss and optimal design of its structure without consideration of the wet steam condensing flow and the exhaust hood coupled with the front and rear parts. To better understand the aerodynamic performance influenced by the tilt angle of flow guide inside a diffuser, taking a 600 MW steam turbine as an example, a numerical simulator CFX is adopted to solve compressible three-dimensional （3D） Reynolds time-aver- aged N-S equations and standard k-e turbulence model. And the exhaust hood flow field influenced by different tilt angles of flow guide is investigated with consideration of the wet steam condensing flow and the exhaust hood coupled with the last stage blades and the condenser throat. The result shows that the total pressure loss coefficient and the static pressure recovery coefficient of exhaust hood change regularly and monotonously with the gradual increase of tilt angle of flow guide. When the tilt angle of flow guide is within the range of 30~ to 40~, the static pressure recovery coefficient is in the range of 15.27% to 17.03% and the total pressure loss coefficient drops to approximately 51%, the aerodynamic performance of exhaust hood is significantly improved. And the effectiveenthalpy drop in steam turbine increases by 0.228% to 0.274%. It is feasible to obtain a reasonable title angle of flow guide by the method of coupling the last stage and the condenser throat to exhaust hood in combination of the wet steam model, which provides a practical guidance to flow guide transformation and optimal design in exhaust hood.

Effects of variation in food resources on foraging habitat use by wintering Hooded Cranes(Grus monacha)

Background:The ideal habitat use of waterbirds can be considered to be fixed,but current habitat use depends on environmental conditions,especially those of food characteristics,considered crucial to their use of habitats.Understanding how waterbirds respond to variation in food availability at degraded wetland sites and change their habitat use patterns over spatial and temporal scales should direct future conservation planning.The objectives of this study were to identify these spatial-temporal foraging habitat use patterns of Hooded Cranes(Grus monacha)and their relationship with food characteristics in the severely degraded wetlands of the Shengjin and Caizi lakes along with the Yangtze River floodplain.Methods:We investigated the changes in food characteristics,relative abundance and density of Hooded Cranes in various habitat types across three winter periods from November 2012 to April 2013.We examined the effect of these winter periods and habitat types on the pattern of use by the cranes and explored the relationship between these patterns and food characteristics using linear regression.Results:The food characteristics and habitat use clearly changed over spatial-temporal scales.In the early and mid-winter periods,the most abundant,accessible and frequented food resources were found in paddy fields,while in the late period the more abundant food were available in meadows,which then replaced the paddy fields.There were fewer effects of winter periods,habitat types and their interactions on habitat use patterns except for the effect of habitat types on the relative abundance,determined as a function of food abundance,but independent of food depth and sediment permeability.Conclusions:In response to the degradation and loss of lake wetlands,the cranes shifted their habitat use patterns by making tradeoffs between food abundance and accessibility over spatial-temporal scales that facilitated their survival in the mosaic of these lake wetlands.

Effect of water level fluctuations on temporal-spatial patterns of foraging activities by the wintering Hooded Crane(Grus monacha)

Background:The Yangtze River floodplain provides important wintering habitats for Hooded Cranes(Grus monacha) in China.Fluctuations in the water level change foraging habitat and food availability,affecting their temporal-spatial patterns of foraging activities.It is of considerable importance to investigate the effect of these fluctuations on food availability for wintering Hooded Cranes and their foraging response to these changes.Understanding their behavior patterns is beneficial in protecting the wintering crane population and restoring their wintering habitats.Methods:A field survey of the winter behavior of cranes was carried out at Shengjin Lake from November in 2013 to April in 2014.Habitat variables,as well as the spatial distribution and behavior patterns of wintering cranes at their foraging sites during five stages of water level fluctuation were collected.Based on this data we analyzed the relationship of foraging behavior relative to water level fluctuations and habitat types.Results:The foraging habitats used by Hooded Cranes varied at the different water level stages.As the water level decreased,the use of meadows and mudflats increased.When the water dropped to its lowest level,the use by the Hooded Crane in the mudflats reached a peak.There were statistically significant differences in time budget in the three types of habitats over the five stages of the water level.In the mudflats,the foraging behavior and maintenance behavior varied significantly with the water level,while the alert behavior showed little variation.Analysis of a generalized linear model showed that the five water level stages and three habitat types had a significant effect on foraging behavior,while the combined effect of these two variables was significant on the foraging time budget and the length of foraging activity of the Hooded Crane.Conclusions:With the decrease in the water level,the use of mudflats by Hooded Cranes increased correspondingly.Food availability in different habitats was affected by changes in the water level.The Hooded Crane adjusted its foraging patterns and made full use of the three available types of habitat in order to acquire enough food in response to fluctuations in the water level.

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.

A CFD study on optimal venting volume and air flow distribution in a special designed hood system for controlling dust flow

A novel hood structure has been designed for the dust control system in the foundry in order to improve the working environment. A composite strategy has been applied for comparative analysis of the optimal venting volume and the airflow distribution between the conventional hood and the novel one in this study. A Computational Fluid Dynamic (CFD) method is used to simulate the airflow fields and dust-polluted air moving paths. The CFD results show that a two-outlet hood, with one outlet located on the left of the hood, is better for improving dust-polluted air than the hood with one outlet only. It can be concluded that the number of the outlets as well as their location on the hood has a significant influence on the air flow pattern in the hood. The optimal venting volume is also a major consideration that is discussed in the study. The venting volume should be designed by considering both the effective level of air flow velocity around the dust source and the energy saving. The optimal airflow distribution may reduce the turbulence in the hood system.

NUMERICAL SIMULATION AND EXPERIMENTAL STUDY OF A KIND OF LOCAL EXHAUST VENTILATION HOOD

A new local exhaust ventilation hood is presented. First, the test system inlaboratory room is established. Secondly a mathematical model is developed in terms of the stokesstream function, and the governing equation is solved using finite-difference techniques. Theinjection flow of the exhaust hood is treated as a boundary condition of the main flow. Experimentsresults well agree with the solution of theoretical prediction. The model can, therefore, be used todesign this kind of Aaberg hood. Thirdly the important parameters affecting the performance ofAaberg exhaust hood are taken into account. In the mean time the connection of these parameters isdeduced by multivariate linear regression based on the experimental results. The work is usefulwhether in designing this kind of local ventilation Aaberg exhaust hood or in predicting the hood'swork performance.

Population sizes and group characteristics of Siberian Crane(Leucogeranus leucogeranus) and Hooded Crane(Grus monacha) in Poyang Lake Wetland

Both the Siberian Crane(Leucogeranus leucogeranus) and Hooded Crane(Grus monacha) have limited population sizes and are considered endangered by domestic Chinese and international agencies.To document the current size of their respective populations and characterize their groups,between October 2012 and April 2013 we undertook fieldwork at four nature reserve areas within the Poyang Lake wetlands.We divided Poyanghu National Nature Reserve(PYH) into the Wucheng(PWC) and Hengfeng areas(PHF),because each are each located in different counties.Our fieldwork showed that the Siberian Crane occurred mainly in PYH(364 in the PHF,158 in the PWC) and the Nanjishan Wetland National Nature Reserve(NJS,with 200 individuals).The Hooded Crane was mainly distributed in PYH(302 in the PHF and 154 in the PWC).Family groups accounted for more than 50% of the total number of groups among both species,with Hooded Cranes forming more family groups than Siberian Cranes.Typically,these groups were formed of two adults with one offspring(Siberian Crane),and two adults with two offspring(Hooded Crane),with the mean family group size of the Siberian Crane and Hooded Crane being respectively 2.65±0.53(n=43) and 3.09±0.86(n=47) individuals per group.The mean collective group size of the Siberian Crane and Hooded Crane included 28.09±24.94(n=23) and 28.94±27.97(n=16) individuals per group,respectively,with the proportion of juveniles among Hooded Cranes being more than double that seen among the Siberian Cranes.

Comparing the intestinal bacterial communies of sympatric wintering Hooded Crane (Grus monacha) and Domestic Goose(Anser anser domesticus)

Background:Gut microbiota play crucial roles in host health.Wild birds and domestic poultry often occupy sympatric habitats,which facilitate the mutual transmission of intestinal microbes.However,the distinct intestinal microbial communities between sympatric wild birds and poultry remain unknown.At present,the risk of interspecies transmission of pathogenic bacteria between wild and domestic host birds is also a research hotspot.Methods:This study compared the intestinal bacterial communities of the overwintering Hooded Crane(Grus monacha)and the Domestic Goose(Anser anser domesticus)at Shengjin Lake,China,using Illumina high-throughput sequencing technology(Mi-Seq platform).Results:Our results revealed that Firmicutes,Actinobacteria,Proteobacteria,Bacteroidetes and Chloroflexi were the dominant bacterial phyla in both hosts.The gut bacterial community composition differed significantly between sympatric Hooded Cranes and Domestic Geese.However,the hosts exhibited little variation in gut bacterial alphadiversity.The relative abundance of Firmicutes was significantly higher in the guts of the Hooded Cranes,while the relative abundances of Actinobacteria,Proteobacteria,Bacteroidete and Chloroflexi were significantly higher in guts of Domestic Geese.Moreover,a total of 132 potential pathogenic operational taxonomic units(OTUs)were detected in guts of Hooded Cranes and Domestic Geese,and 13 pathogenic OTUs(9.8%)were found in both host guts.Pathogenic bacterial community composition and diversity differed significantly between hosts.Conclusions:The results showed that the gut bacterial community composition differs significantly between sympatric Hooded Cranes and Domestic Geese.In addition,potential pathogens were detected in the guts of both Hooded Cranes and Domestic Geese,with 13 pathogenic OTUs overlapping between the two hosts,suggesting that more attention should be paid to wild birds and poultry that might increase the risk of disease transmission in conspecifics and other mixed species.

Effects of foraging site distances on the intestinal bacterial community compositions of the sympatric wintering Hooded Crane(Grus monacha)and Domestic Duck(Anas platyrhynchos domesticus)

Background:The composition of intestinal microflora in animals is affected by cross-species transmission.In a nature reserve,the foraging sites of waterbirds are relatively fixed,but frequently close to residential areas and can also be visited by domestic fowls.It is easy to result in the trans-species-flock dispersal of gut microbes between the wild birds and domestic fowls.The effects of the variable foraging site distances on the gut microbe structures of the waterbirds and the sympatric domestic fowls are currently unclear,and further research is required to evaluate the impacts of geographic location on cross-infection.Methods:Illumina high-throughput sequencing and bioinformatics analysis software were utilized to compare and analyze the composition of gut microbes from the fecal samples of Hooded Cranes(HC;Grus monacha)and two groups of Domestic Ducks(Anas platyrhynchos domesticus)that foraged at 1 km(ducks in near areas,D-N),and 4 km(ducks in far areas,D-F)away from the habitats of the Hooded Cranes at Shengjin Lake,China.Results:The results showed that there were significant differences in the alpha-diversity of the gut bacteria in the HC,D-N,and D-F samples under the interspecific distance factor.The dominant bacterial phyla,Cyanobacteria and Proteobacteria,showed correlations with distance for each host.The D-N group had more diverse intestinal flora than the D-F,as they were physically closer to the HC and had more indirect contact and cross-transmission of their gut microbes.More potentially pathogenic bacterial sequences,and Operational Taxonomic Units(OTUs)were found in the D-N than in HC and D-F.Conclusions:Hooded Cranes and the Domestic Duck populations at variable distances from the cranes showed significant differences in their intestinal bacteria and potentially pathogenic bacteria.The closer the foraging sites were,the easier the intestinal flora spread across species.The results provide a basis for determining the safe distance between wild birds and domestic fowls in a nature reserve.

Annual spatio-temporal migration patterns of Hooded Cranes wintering in Izumi based on satellite tracking and their implications for conservation

Background: The Hooded Crane(Grus monacha) is listed as a vulnerable species by IUCN. Knowledge about the migration of the Hooded Crane is still limited. Here we reported the spatio-temporal migration patterns of Hooded Cranes wintering in Izumi, Japan, as well as important stopover areas for their conservation.Methods: Four adult and five subadult cranes, all wintering in Izumi, Japan, were fitted with satellite transmitters(GPS–GSM system) at their stopover sites in northeastern China in 2014 and 2015. We analyzed the time and duration of adults and subadults in spring and autumn migration, as well as the time and duration they stayed in breeding and wintering ground. In addition, we analyzed the land use of the cranes in stopover areas.Results: Adult cranes took much longer time to migrate both north in spring(mean days) compared with subadult cranes(15.3 and 5.2 days, respectively). H= 44.3 days) and south in fall(mean = 54.0 owever, the subadults had longer wintering(mean = 149.8 days) and nomadic(breeding season for adults) seasons(mean d with adults(133.8 and 122.3 days, respectively). Three important stopover areas have been= 196.8 days) compare identified: the region around Muraviovka Park in Russia, the Songnen Plain in China, and the west coast of South Korea, where cranes spent most of their migration time(62.2 and 85.7% in spring and autumn, respectively). During migration, nomadic period and winter, Hooded Cranes usually stay in croplands for resting and feeding. In non-wintering season, less than 6% of stopover sites were located within protected areas.Conclusion: Overall, our results contribute to understanding the annual spatio-temporal migration patterns of Hooded Cranes in the eastern flyway, and planning conservation measures for this species.

Dramatic shifts in intestinal fungal community between wintering Hooded Crane and Domestic Goose

Background:The intestinal microbiota play remarkable roles in maintaining the health of their hosts.Recent studies focused on gut bacterial diversity in birds and poultry,with little information about the ecological functions of their gut fungal community.Methods:The high-throughput sequencing was applied to compare intestinal fungal community structure between Hooded Crane(Grus monacha)and Domestic Goose(Anser anser domesticus),and infer the potential pathogens of each species at Shengjin Lake of China.Results:Intestinal fungal alpha diversity was higher in Hooded Crane than Greylag Goose(Anser anser).Gut fungal community composition showed dramatic shifts between the two species.Hooded Cranes mainly eat Vallisneria natans and Potamogeton malaianus,while artificial hurl food(i.e.,paddy)was the main food resource for Domestic Geese,suggesting that the variations in fungal community might be induced by different diets between the two hosts.Two enriched genera(i.e.,Acremonium and Rhodotorula)which could increase host's digestion were detected in guts of Hooded Cranes.In addition,there were 42 pathogenic amplicon sequence variants(ASVs),17%of which shared in Hooded Crane and Greylag Goose.The Hooded Crane had higher gut fungal pathogenic diversity and abundance relative to Greylag Goose.Conclusions:The study demonstrated that divergence in intestinal fungal community structure might be induced by different diets between wintering Hooded Crane and Domestic Goose.Hooded Crane might rely more on their gut fungal taxa to acquire nutrients from indigestible food resources.Our study also implied that more research should focus on intestinal pathogens in wild birds and domestic poultry,as they might increase risk of disease in other animals,even human beings.The degree of cross infection in pathogens among wild birds and sympatric poultry should be clearly verified in future study.

Shifts in foraging behavior of wintering Hooded Cranes(Grus monacha) in three different habitats at Shengjin Lake, China

Background: Wetland loss and degradation result in a reduction in the availability and quality of food for wintering waterbirds. Birds normally modify their foraging behavior to adapt to variations in food availability. In this study, we compared shifts in foraging behavior of Hooded Cranes(Grus monacha) in three different habitats at Shengjin Lake, China to understand the response of these cranes to changes in habitat.Methods: We investigated the food density and foraging behavior of Hooded Cranes in Shengjin Lake National Nature Reserve from November 2014 to April 2015. We used regression equations to describe the changes in food density. A total of 397 behavioral observations were used in the analyses of their foraging efforts. We fitted a candidate set of generalized mixed linear models to analyze the relationship of foraging efforts and food density. We used a method of information theory to guide the selection of the model and Akaike's Information Criterion to calculate the value of each model. The relationship between food density, disturbances and foraging behavior was illustrated using a generalized linear model.Results: Along with the temporal variation and exploitation of food biomass, the food density varied widely among foraging sites. During the early winter period, foraging efforts were more pronounced in the paddy fields and meadows but not significantly different among the three habitats. The cranes spent more foraging effort in the paddy fields and meadows during the middle stage and in the meadows and mudflats during the late winter. The results of the generalized linear model showed that food density and disturbances had different effects on the rate of foraging success during the winter, while the effect of foraging effort was not significant. Furthermore, the rate of feeding success was markedly affected by disturbances in the paddy fields. The combined action of food density and disturbances had a significant effect on the rate of foraging success in the meadows, while the effect of foraging effort was also not significant in three habitats.Conclusions: Changes in foraging behavior were significant in three habitats, which were affected by food density and disturbances. The rate of foraging success increased in the habitat with low food density and low disturbances to increase the foraging efficiency in the lake. With abundant food and a high level of disturbance, the rate of foraging success decreased to ensure more secure access to food.