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,Ch...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.展开更多
The Chinese Egret(Egretta eulophotes)is a globally threatened bird species living on the coast and islands of Liaoning,northeastern China,mainly in summer.To further protect the breeding population of Chinese Egrets,i...The Chinese Egret(Egretta eulophotes)is a globally threatened bird species living on the coast and islands of Liaoning,northeastern China,mainly in summer.To further protect the breeding population of Chinese Egrets,it is important to understand the current protection status of their distribution sites at pre-migration period and migration routes.Thirty-three individuals were tagged with satellite transmitters at Fantuo Island in Changhai and Xingren Island in Zhuanghe,Liaoning Province,northeastern China,in July of 2016,2017,and 2018,to identify important distribution sites during the pre-migration period,as well as detailed migration routes.The results showed that coastal mudflats in Liaoning and the west coast of North Korea were important feeding and roosting sites for fledgling Chinese Egrets from August to September.The home range sizes in August were significantly larger than in September.The eastern coast from Shandong to Guangdong,as well as Taiwan,China,and Manila Bay and Galileo Islands in the Philippines,were important stopover sites during fall migration.Specifically,we found that the egrets’autumn migration could be divided into four routes,i.e.,sea-crossing migration(SCM),coastal migration(CM),inland migration(IM),and mixed migration(MM).The migration distance,timing,speed,and straightness of the four routes also differed.The SCM routes were the straightest,and had the fastest migration speed and shortest travel time,while the IM routes had the lowest straightness and speed,and the longest duration.Manila Bay and Bohol Island in the Philippines,the west coast of Tanintharyi in Myanmar,and the Zengwun River Estuary in Taiwan,China,were wintering sites.Our findings on the key distribution sites along pre-migration and fall migration routes,including some stopover sites,have important implications for the conservation of and global action plan development for the vulnerable Chinese Egret.展开更多
Background: Noninvasive and nondestructive DNA sampling techniques are becoming more important in genetic studies because they can provide genetic material from wild animals with less or even without disturbance,which...Background: Noninvasive and nondestructive DNA sampling techniques are becoming more important in genetic studies because they can provide genetic material from wild animals with less or even without disturbance,which is particularly useful for the study of endangered species,i.e.,birds.However,nondestructively and noninvasively sampled DNA may,in some cases,be inadequate in the amount and quality of the material collected,which can lead to low amplification success rates and high genotyping errors.Methods: In this study,noninvasive(eggshell swab,shed feather and feces),nondestructive(plucked feather and buccal swab) and invasive(blood) DNA samples were collected from the vulnerable Chinese Egret(Egretta eulophotes).DNA concentrations,PCR amplification success and microsatellite genotyping errors of different sample types were evaluated and compared to determine whether noninvasive and nondestructive samples performed as well as invasive samples in our experimental procedures.Results: A total of 159 samples were collected in the field.Among the different sample types,the highest DNA concentrations(154.0–385.5 ng/μL) were obtained from blood.Those extracted from fecal samples were the lowest,ranging from 1.25 to 27.5 ng/μL.Almost all of the DNA samples,i.e.,95.59 %,were successfully amplified for mt DNA(n = 152) and 92.76 % of mt DNA samples were successfully genotyped for at least five of the nine microsatellite loci tested(n = 141).Blood samples and buccal swabs produced reliable genotypes with no genotyping errors,but in feces,allelic dropouts and false alleles occurred in all nine loci,with error rates ranging from 6.67 to 38.10 % for the dropouts and from 6.06 to 15.15 % for the false alleles.Conclusions: These results indicate that both nondestructive and noninvasive samplings are suitable for avian microsatellite genotyping,save for fecal DNA.However,we should remain cautious of the appearance of genotyping errors,especially when using noninvasive material.展开更多
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 (Egrett...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.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.40876077,30970380)the Fujian Natural Science Foundation of China (2008S0007,2009J01195)
文摘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.
基金supported by the National Key Research and Development Program of China (No. 2019YFA0607103)Program of National Forestry and Grassland Administration (No.213023721203)
文摘The Chinese Egret(Egretta eulophotes)is a globally threatened bird species living on the coast and islands of Liaoning,northeastern China,mainly in summer.To further protect the breeding population of Chinese Egrets,it is important to understand the current protection status of their distribution sites at pre-migration period and migration routes.Thirty-three individuals were tagged with satellite transmitters at Fantuo Island in Changhai and Xingren Island in Zhuanghe,Liaoning Province,northeastern China,in July of 2016,2017,and 2018,to identify important distribution sites during the pre-migration period,as well as detailed migration routes.The results showed that coastal mudflats in Liaoning and the west coast of North Korea were important feeding and roosting sites for fledgling Chinese Egrets from August to September.The home range sizes in August were significantly larger than in September.The eastern coast from Shandong to Guangdong,as well as Taiwan,China,and Manila Bay and Galileo Islands in the Philippines,were important stopover sites during fall migration.Specifically,we found that the egrets’autumn migration could be divided into four routes,i.e.,sea-crossing migration(SCM),coastal migration(CM),inland migration(IM),and mixed migration(MM).The migration distance,timing,speed,and straightness of the four routes also differed.The SCM routes were the straightest,and had the fastest migration speed and shortest travel time,while the IM routes had the lowest straightness and speed,and the longest duration.Manila Bay and Bohol Island in the Philippines,the west coast of Tanintharyi in Myanmar,and the Zengwun River Estuary in Taiwan,China,were wintering sites.Our findings on the key distribution sites along pre-migration and fall migration routes,including some stopover sites,have important implications for the conservation of and global action plan development for the vulnerable Chinese Egret.
基金supported by the National Natural Science Foundation of China(Grant nos. 41476113,31000963 and 31272333)the Fujian Natural Science Foundation of China (2010Y2007)
文摘Background: Noninvasive and nondestructive DNA sampling techniques are becoming more important in genetic studies because they can provide genetic material from wild animals with less or even without disturbance,which is particularly useful for the study of endangered species,i.e.,birds.However,nondestructively and noninvasively sampled DNA may,in some cases,be inadequate in the amount and quality of the material collected,which can lead to low amplification success rates and high genotyping errors.Methods: In this study,noninvasive(eggshell swab,shed feather and feces),nondestructive(plucked feather and buccal swab) and invasive(blood) DNA samples were collected from the vulnerable Chinese Egret(Egretta eulophotes).DNA concentrations,PCR amplification success and microsatellite genotyping errors of different sample types were evaluated and compared to determine whether noninvasive and nondestructive samples performed as well as invasive samples in our experimental procedures.Results: A total of 159 samples were collected in the field.Among the different sample types,the highest DNA concentrations(154.0–385.5 ng/μL) were obtained from blood.Those extracted from fecal samples were the lowest,ranging from 1.25 to 27.5 ng/μL.Almost all of the DNA samples,i.e.,95.59 %,were successfully amplified for mt DNA(n = 152) and 92.76 % of mt DNA samples were successfully genotyped for at least five of the nine microsatellite loci tested(n = 141).Blood samples and buccal swabs produced reliable genotypes with no genotyping errors,but in feces,allelic dropouts and false alleles occurred in all nine loci,with error rates ranging from 6.67 to 38.10 % for the dropouts and from 6.06 to 15.15 % for the false alleles.Conclusions: These results indicate that both nondestructive and noninvasive samplings are suitable for avian microsatellite genotyping,save for fecal DNA.However,we should remain cautious of the appearance of genotyping errors,especially when using noninvasive material.
文摘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.
