The territories and territrial behavior of White-naped Crane and Red-crowned Crane were studied in Rindian County of Heilongjiang province from March to May in 1986-1988.Eight territories of White-naped crane and six ...The territories and territrial behavior of White-naped Crane and Red-crowned Crane were studied in Rindian County of Heilongjiang province from March to May in 1986-1988.Eight territories of White-naped crane and six of Red-crowned Crane were investigated.The results show that two species have successtively occupied the same territory for many years.The maximum size of occupied territory by Red-crowned Crane is 4.0 km 2 with the average of 3.65 km 2 and by White-naped crane is 10.7 km 2 with the average of 7 km 2.During most period of breeding, the size of territories of two species were gradually reduced to less than 1.5 km 2 until nesting period ,The area of territories of White-naped Crane with fixed foraging crop field is smaller than that of the territories without crop field.展开更多
In order to measure the impact of changes in the marsh on breeding Red-crowned Cranes (Grus japonensis) and White-naped Cranes (G.vipio) in the Sanjiang Plain,we conducted a complete crane súrvey in each of the s...In order to measure the impact of changes in the marsh on breeding Red-crowned Cranes (Grus japonensis) and White-naped Cranes (G.vipio) in the Sanjiang Plain,we conducted a complete crane súrvey in each of the summers of 2007 and 2008,and obtained information on the changes in its marsh through interpretation of satellite images in 1986,1995,2000 and 2005.A comparison between the 1984 and 2008 census shows that:1) the number of Red-crowned Cranes remained stable at about 300 birds,while the number of White-naped Cranes increased markedly; 2) the estimates of nests of Red-crowned cranes are close to the numbers of 1984,while approximately 90% of the nests of these two crane species were distributed over five national nature reserves (NNRs); 3) the two crane species became more concentrated in three regions,i.e.,the Fuyuan Delta,the middle reaches of the Naoli and Qixing rivers,and the Xingkai Lake wetlands,rather as formerly in six regions.The area of the marsh decreased by 45% within the 20-year period from 1986 to 2005.The major loss of the marsh area was in the form of a conversion to paddy fields and dry land,which can be primarily attributed to direct human activity under various economic and policy drivers.The disappearance of cranes in the Dulu and Abuqin rivers was induced by large-scale agricultural development.The fragmentation into and isolation of small areas of the marsh became increasingly more serious,which resulted in unsuitable condtions for crane breeding in small patches of the marsh.The number of cranes declined from 1984-1995 but had recovered remarkably by 2008,which may be due to theestablishment of a system of nature reserves,in place since 2000.The land ownership of the reserve plays a key role in maintaining the integrity of the wetland ecosystem,especially in Sanjiang,Honghe,Naolihe and Qixinghe NNRs,which together accommodated approximately 80% of the population of cranes.However,we did not discover any nests at all in the provincial and municipal reserves,which may be attribute展开更多
By combining satellite tracking,land-cover extracted from Landsite 8 images,and the traditional stable isotope analysis,we studied the habitat selection and food preference of a vulnerable migratory waterbird,the Whit...By combining satellite tracking,land-cover extracted from Landsite 8 images,and the traditional stable isotope analysis,we studied the habitat selection and food preference of a vulnerable migratory waterbird,the Whitenaped Crane(Grus vipio),in one of its key stagging sites,the Shandian River Basin in the semi-arid northern China,to provide knowledge that is critical for its conservation in the Anthropocene.Our results showed that the White-naped Cranes used both uplands and natural wetlands in the stopover site.While the cranes used farmland and natural land cover equally as night-time roosting grounds,they spent most daytime foraging at farmlands.Despite the extensive usage of croplands as their foraging ground,the Bayesian mixing models based on stable isotopic analysis revealed that crop residues after harvesting,such as Maize(Zea mays)and Naked Oat(Avena chinensis),were only a small fraction of the White-naped Cranes’diet(~19%),and their diet composited mainly natural plants,such as Allium ledebourianum,Potentilla anserina,and P.tanacetifoli.Moreover,more than 20%of the total wetlands in the region were modelled as home range of the cranes.On contrast,less than 10%of croplands and about 1%of the unused uplands were identified as home range.In addition,the entire core habitats were located in natural wetlands.Our findings demonstrated the importance of natural wetlands for the survival of the threatened crane.However,the satellite-derived land cover data showed that croplands increased rapidly in the last decade in this area,at the expense of natural wetlands.With the sharp decrease of White-naped Crane population in China,the conservation of stopover sites becomes imperative.Based on our analysis,we recommend the following management actions:conserving adequate natural wetland area,regulating anthropogenic pressures such as the use of herbicides,expanding the duration and extent of current conservation regulations,establishing a comprehensive monitoring program,and initiating basin-scale ecological restora展开更多
文摘The territories and territrial behavior of White-naped Crane and Red-crowned Crane were studied in Rindian County of Heilongjiang province from March to May in 1986-1988.Eight territories of White-naped crane and six of Red-crowned Crane were investigated.The results show that two species have successtively occupied the same territory for many years.The maximum size of occupied territory by Red-crowned Crane is 4.0 km 2 with the average of 3.65 km 2 and by White-naped crane is 10.7 km 2 with the average of 7 km 2.During most period of breeding, the size of territories of two species were gradually reduced to less than 1.5 km 2 until nesting period ,The area of territories of White-naped Crane with fixed foraging crop field is smaller than that of the territories without crop field.
基金supported by the Conservation Fund of the State Forestry Administration of China and the Siberian Crane Wetland GEF/UNEP Project(GF/2712-03-4627)
文摘In order to measure the impact of changes in the marsh on breeding Red-crowned Cranes (Grus japonensis) and White-naped Cranes (G.vipio) in the Sanjiang Plain,we conducted a complete crane súrvey in each of the summers of 2007 and 2008,and obtained information on the changes in its marsh through interpretation of satellite images in 1986,1995,2000 and 2005.A comparison between the 1984 and 2008 census shows that:1) the number of Red-crowned Cranes remained stable at about 300 birds,while the number of White-naped Cranes increased markedly; 2) the estimates of nests of Red-crowned cranes are close to the numbers of 1984,while approximately 90% of the nests of these two crane species were distributed over five national nature reserves (NNRs); 3) the two crane species became more concentrated in three regions,i.e.,the Fuyuan Delta,the middle reaches of the Naoli and Qixing rivers,and the Xingkai Lake wetlands,rather as formerly in six regions.The area of the marsh decreased by 45% within the 20-year period from 1986 to 2005.The major loss of the marsh area was in the form of a conversion to paddy fields and dry land,which can be primarily attributed to direct human activity under various economic and policy drivers.The disappearance of cranes in the Dulu and Abuqin rivers was induced by large-scale agricultural development.The fragmentation into and isolation of small areas of the marsh became increasingly more serious,which resulted in unsuitable condtions for crane breeding in small patches of the marsh.The number of cranes declined from 1984-1995 but had recovered remarkably by 2008,which may be due to theestablishment of a system of nature reserves,in place since 2000.The land ownership of the reserve plays a key role in maintaining the integrity of the wetland ecosystem,especially in Sanjiang,Honghe,Naolihe and Qixinghe NNRs,which together accommodated approximately 80% of the population of cranes.However,we did not discover any nests at all in the provincial and municipal reserves,which may be attribute
基金This research was funded by National Natural Science Foundation of China(No.31971400)the Fundamental Research Funds for the Central Universities(No.BLX202144).
文摘By combining satellite tracking,land-cover extracted from Landsite 8 images,and the traditional stable isotope analysis,we studied the habitat selection and food preference of a vulnerable migratory waterbird,the Whitenaped Crane(Grus vipio),in one of its key stagging sites,the Shandian River Basin in the semi-arid northern China,to provide knowledge that is critical for its conservation in the Anthropocene.Our results showed that the White-naped Cranes used both uplands and natural wetlands in the stopover site.While the cranes used farmland and natural land cover equally as night-time roosting grounds,they spent most daytime foraging at farmlands.Despite the extensive usage of croplands as their foraging ground,the Bayesian mixing models based on stable isotopic analysis revealed that crop residues after harvesting,such as Maize(Zea mays)and Naked Oat(Avena chinensis),were only a small fraction of the White-naped Cranes’diet(~19%),and their diet composited mainly natural plants,such as Allium ledebourianum,Potentilla anserina,and P.tanacetifoli.Moreover,more than 20%of the total wetlands in the region were modelled as home range of the cranes.On contrast,less than 10%of croplands and about 1%of the unused uplands were identified as home range.In addition,the entire core habitats were located in natural wetlands.Our findings demonstrated the importance of natural wetlands for the survival of the threatened crane.However,the satellite-derived land cover data showed that croplands increased rapidly in the last decade in this area,at the expense of natural wetlands.With the sharp decrease of White-naped Crane population in China,the conservation of stopover sites becomes imperative.Based on our analysis,we recommend the following management actions:conserving adequate natural wetland area,regulating anthropogenic pressures such as the use of herbicides,expanding the duration and extent of current conservation regulations,establishing a comprehensive monitoring program,and initiating basin-scale ecological restora