The Red-crowned Crane (Grus japonensis) is a globally endangered species.Although this species has received much attention by scientists,conservationists and the general public,the continental population of the Red-cr...The Red-crowned Crane (Grus japonensis) is a globally endangered species.Although this species has received much attention by scientists,conservationists and the general public,the continental population of the Red-crowned Crane continues to face serious threats which affect not only its population dynamics but also its breeding and wintering habitats.Habitat loss and deterioration are the main causes of the decline of its population.With the massive loss of habitats in all parts of its range - breeding,stopover and wintering grounds - the cranes have been forced into crops and farmlands where cranes are more vulnerable to human activities,such as poisoning the cranes and conflicts with farmers.From our review of studies done over 30 years,the eastern flyway subpopulation has been stable or slightly increasing and the western flyway subpopulation of the Red-crowned Crane has sharply declined in recent years.The wintering population for the western flyway has declined from over 1100 to less than 500 birds.Not only is the size of the population reduced to less than 50％,but most recently the decline has occurred with frightening speed,by 50-150 birds per winter.The current wintering range for the west flyway is only about 8％ of its extent in the 1980s.Urgent actions for habitat protection,law enforcement and education need to stop the declining trend for this species.展开更多
From January to March 2005, the effects of group size on the vigilance behavior of wintering Common Cranes Grus grus were studied at Lashihai Lake, Yunnan Province, China. We used scan sampling to record the group siz...From January to March 2005, the effects of group size on the vigilance behavior of wintering Common Cranes Grus grus were studied at Lashihai Lake, Yunnan Province, China. We used scan sampling to record the group sizes and the number of vigilant individuals in each group, and focal sampling to record the frequency and duration of individual vigilance behavior. Both the vigilance efforts of groups and individuals significantly decreased as group size increased, but when the group size exceeded 30 individuals, the decrease of group vigilance became not significant （P 〉 0. 05）, and the vigilance duration of adult cranes increased （P 〈 0.01 ）. The vigilance frequency of adults increased （P 〈 0.05） when the size exceeded 50 individuals. Presumably, the maximal group size allowing the lowest vigilance for juvenile cranes was larger than that for adults, and the flocks composed of 20 to 30 individuals represented the optimal group size of wintering Common Cranes by considering only the vigilance behavior. Further research should focus on the synthesized effects of various factors.展开更多
We investigated collisions with power lines by Black-necked Cranes (Grus nigricollis) and Barheaded Geese (Anser indicus) along the Yarlung Tsangpo River in the Tibet Autonomous Region during two winters.Three segment...We investigated collisions with power lines by Black-necked Cranes (Grus nigricollis) and Barheaded Geese (Anser indicus) along the Yarlung Tsangpo River in the Tibet Autonomous Region during two winters.Three segments of a 35 kV transmission line were surveyed each winter for injured and dead birds.Injured birds disappeared within five days of their initial detection; most dead birds encountered had been scavenged.We recorded two dead geese on transects and two injured geese and two dead cranes adjacent to transects.We found a higher incidence of bird strikes along power line segments close to roosting and foraging areas.We recommend that power lines,new or old,located in the flight path from nocturnal roosts,near important foraging areas or crossing the mouths of important agricultural valleys should be marked with colored and/or reflecting devices that have been proven to reduce crane and goose collisions.展开更多
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 temp...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 wate展开更多
We surveyed all known wintering areas of the Black-necked Crane (Grus nigricollis) in Zhigatse Prefecture of the Tibet Autonomous Region during three winters.Our surveys confirm that Zhigatse Prefecture is the most im...We surveyed all known wintering areas of the Black-necked Crane (Grus nigricollis) in Zhigatse Prefecture of the Tibet Autonomous Region during three winters.Our surveys confirm that Zhigatse Prefecture is the most important wintering area for the species,accounting in some years for as much as 39％ of the estimated world population.Counts ranged from a high of 4240 cranes in January 2007 to a low of 2636 in February 2009.Chick recruitment (chicks/100 cranes) ranged from 8.2 (January 2010) to 11.3 (January 2007).The highest concentration of cranes during all three surveys occurred on the 60 km stretch of the Yarlung Tsangpo (River) between Lhaze and Phuntsoling.To evaluate potential impacts of the Xietongmen Copper Mine,we monitored wintering crane numbers prior to mine installation in an intensive study area located between the Shab Chu Valley and the city of Zhigatse.Our surveys recorded on average 820 ± 83 cranes (SE; n =8) in this area.With the installation of the mine at a location ～50 km west of Zhigatse,increased traffic and development on the north side of the Yarlung River will likely result in a shift in crane distribution away from the north side,to nearby suitable habitats.Based on our survey results,we recommend three areas hosting high numbers of cranes in the vicinity of the mine be added to the Yarlung Tsangpo Middle Reaches Black- necked Crane Nature Reserve.These areas are Nierixiong and Jiaqingze Villages in Nierixiong Xiang and the Shab Chu Valley.展开更多
White-naped crane （Grus vipio） is a globally threatened spe- cies. It is very important to analyze its nest site selection in circum- stances where there are multiple disturbances, and also helpful to accu- mulate v...White-naped crane （Grus vipio） is a globally threatened spe- cies. It is very important to analyze its nest site selection in circum- stances where there are multiple disturbances, and also helpful to accu- mulate valuable information about this threatened species and supply scientific suggestions for conservation and management. We studied nest site selection and the effects of environmental variables on nesting habits of white-naped crane at Zhalong National Nature Reserve, Qiqihar City, Heilongiiang, China, during March-May of 2002-2008. White-naped crane responded and adapted to changes in the quality of the spatial environments of landscape and microhabitat under multiple environ- mental disturbances. Nest site selection included two scales and two choices, namely the choice of nest site habitat type within the macro-habitat scale and nest site micro-habitat selection within the mi- cro-habitat scale. Nest sites were recorded only in reed marshes. The choice of nest site micro-habitat included three basic elements and six factors, namely incubation element （nest parameters factor, incubation temperature factor and incubation humidity factor）, safety element （pro- tection factor and concealment factor）, and food element （water factor）. Water, remnant reed clusters, and fire were major resource management challenges during the breeding period for the white-naped crane in this Reserve.展开更多
The Hooded Crane (Grus monacha) is a waterbird wintering in the wetlands of the middle and lower reaches of the Yangtze River, China. The gradual habitat loss resulting from wetland degradation may have posed negative...The Hooded Crane (Grus monacha) is a waterbird wintering in the wetlands of the middle and lower reaches of the Yangtze River, China. The gradual habitat loss resulting from wetland degradation may have posed negative effects on the structure of our wintering populations. For its effective protection, it is important to conduct an intensive study on the genetic structure of this population. A total of 221 faecal samples, nine feather samples and four muscle samples of Hooded Cranes from four wintering populations, i.e., from Caizi Lake and Shengjin Lake in Anhui, Poyang Lake in Jiangxi and Chongming Dongtan in Shanghai, were collected for this study. Full-length 1103–1104 bp mtDNA D-loop sequences from 72 samples were amplified using PCR. Based on our amplified D-loop sequences and the sequences of two individual birds obtained from GenBank (AB017625 and AB023813), we analyzed the genetic structure of these four wintering Hooded Crane populations. Twenty six variable sites were found among 72 target sequences in the four wintering populations and 23 haplotypes were defined. Genetic diversity analyses showed that the haplotype diversity of Hooded Cranes was 0.823 ± 0.042 with a nucleotide diversity of 0.00157 ± 0.00021. The FST values of the four populations show that there is no significant genetic differentiation among the populations of Hooded Cranes wintering in the middle and lower reaches of the Yangtze River. Tajima’s D and Fu’s tests suggest that the Hooded Crane populations may have experienced population expansion in their evolutionary history.展开更多
Facing climate and land use change,a species’ability to successfully adapt to changing environments is crucial for its survival.Extensive drainage and intensification of agriculture and forestry set wetlands and asso...Facing climate and land use change,a species’ability to successfully adapt to changing environments is crucial for its survival.Extensive drainage and intensification of agriculture and forestry set wetlands and associated species at risk of population declines.The population of Common Cranes(Grus grus)has experienced considerable fluctuations over the last century.Despite increasing population numbers,hatching success seemed to have decreased over the last years.The aim of this study was to identify factors influencing hatching success and nest survival of Common Cranes based on analyses of long-term individual-based monitoring data from northeastern Germany and evaluate the species ability to adapt to changing environments.Hatching success decreased over the course of the study period from 0.75 to 0.55.Surprisingly,nest survival and hatching success did not vary across different nesting habitats,whereas factors such as female age,timing of nest initiation and breeding pair density were found to have significant effects on hatching success.Older females showed higher hatching success,even though the proportion of unhatched eggs was highest in females aged 20 years or older.Early nest initiation had a positive effect on hatching success.Water levels are more favorable early in the nesting season,whereas increasing evaporation with time causes water levels to decrease,granting easier access for predators.Independently of female age,hatching success decreased with increasing numbers of breeding pairs within a 2-km radius around a nesting site.High population densities intensify competition for resources and promote intraspecific interactions,affecting reproductive outcome negatively.This study gives first insights into mechanisms behind population regulation in Common Cranes,highlighting the importance of population dynamics and individual features.We suggest to further investigate density dependent effects including landscape and habitat features as well as reproductive success in terms of chick survival,since s展开更多
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 o...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.展开更多
Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. Th...Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. The result sho wed that the influence from human activities on the wetland habitat of red-crow ned cranes was prominent with the development of oil and agricultural exploitati on, and the habitat pattern of red-crowned cranes had been obviously changed by the human disturbance during the ten years. The areas with high Spatial Diversi ty values (SD≥0.65) and that with mid-high values (0.5≤SD< 0.65), which const ituted the main part of suitable habitat of red-crowned cranes,had reduced to 9142ha and 5576ha respectively, with the shrinking of natural land cover, such a s reed and Suaeda community. The habitat pattern became more fragmented, which w as caused by roads and wells during oil exploration. It was indicated that the s uitability and quality of habitat for red-crowned cranes in the Liaohe Delta we re degraded in the last decade. The results also showed that diversity index cou ld reflect the habitat suitability of red-crowned cranes quantitatively and des cribe the spatial pattern of the habitat explicitly. This study will provide a s cientific basis for habitat protection of red-crowned cranes and other rare spe cies in wetlands.展开更多
Through scanning electron microscope, various trpes of feathers in various parts of red-crown crane--a kind of rare and precious bird were observed micrographically. It was shown in the result that in different type o...Through scanning electron microscope, various trpes of feathers in various parts of red-crown crane--a kind of rare and precious bird were observed micrographically. It was shown in the result that in different type of feather, the barbules show a great variation in their morphology and structure. This observation can be a basic reference for the taxonomy using the feather structure and the study of systematic relationship.展开更多
Semen characteristics of naturally fertile pairs and their correlation with fertility of eggs in Florida sandhill crane (Grus canadensis pratensis) were examined. Six pairs were used in this experiment, and all of the...Semen characteristics of naturally fertile pairs and their correlation with fertility of eggs in Florida sandhill crane (Grus canadensis pratensis) were examined. Six pairs were used in this experiment, and all of them that had bred before were housed in open individual pens. These pairs were isolated physically each other but not visually and audibly. Semen was collected twice (Tuesday morning and Friday afternoon) from February 26 to June 4, 1993. The standard methods at Patuxent Wildlife Research Center were used collecting and evaluating the semen and spermatozoa. and incubating the eggs. There were statistically individual variations (p<0.05) about successful collecting attempts, semen volume, semen concentration, spermatozoon’s motility,spermatozoon’s number per collection, live spermatozoon’s number, male’s response to semen collection, and morphology of spermatozoa except the giant cell. There was a significantly (p<0.05, correlation coefficient was (0.73 or (1 .00) negative correlation between fertility of eggs and the multiple value of semen (sperm) characteristics of naturally fertile pairs in Florida sandhill crane.展开更多
The Trans-Baikal geographical region is located in southeastern Siberia, Russia, east towards Lake Baikal and include the Daurian steppes. The steppes provide important habitats for several species of cranes, includin...The Trans-Baikal geographical region is located in southeastern Siberia, Russia, east towards Lake Baikal and include the Daurian steppes. The steppes provide important habitats for several species of cranes, including the Red-crowned Crane (Grus japonensis). I have studied the cranes in the area since 1988. The Red-crowned Crane mainly occurs in the Torey Depression (Torey Lake) and the Argun River, which represent the far western edge of the breeding area for the continental population of the Red-crowned Crane. There are some scattering records of the cranes in the Torey Depression from before 1990. The birds appeared regularly and bred from 2002–2007 at Torey Lake. There have been no records since 2008 due to the fact that the wetlands have dried out during the regional climate cycle in the Torey Depression. Three or four individual Red-crowned Cranes have been sighted in Argun in the early 2000’s and then the numbers increased steadily until 2004. At the highest peak in 2004, there were at least 30 pairs of the cranes breeding in the wetlands of the river floodplain. Since then, with the reduced water flow in the Argun River and more and more wetlands drying out, the Red-crowned Crane population decreased dramatically to four or seven territories. The cranes are facing serious threats in the Argun River, such as frequent spring fires, poaching and water pollution. We need to unify efforts from both the Russian and Chinese sides to protect the cranes and their wetland habitat in the area.展开更多
The Black-necked Crane (Grus nigricollis) is an endemic species of the Qinghai-Tibetan Plateau,with its population in Xinjiang largely found in the Kunlun and Altun mountain regions.A survey of the distribution,popula...The Black-necked Crane (Grus nigricollis) is an endemic species of the Qinghai-Tibetan Plateau,with its population in Xinjiang largely found in the Kunlun and Altun mountain regions.A survey of the distribution,population dynamics,flock size and behavior was conducted in Altun Mountain National Natural Reserve from September to November 2011.We investigated the size and distribution of its population in this area with a sample spot survey and by direct counting.We found Black-necked Cranes on the wetlands of Wuzunxiaoer,Yusup Aleksei,Yaziquan,Qimantag,Tula Ranch and elsewhere,where we recorded 126 individual birds of the species in Yixiekepati (37° 15′-37°23′N,90°11′-90°20′E,elevation 3903 m),the largest population we have observed in this area.In the reserve,the population consists of about 180-200 birds.Combined with previous records,we conclude that more than 260 Black-necked Cranes live in Xinjiang.Cranes gathered conspicuously in the middle of October where the highest number of birds appeared on 29 October.All of the cranes had migrated out of this area by 6 November.Time budgets and diurnal behavior rhythms of Blacknecked Cranes were observed in the Yixiekepati wetland at daylight (from 06:00 to 18:00).Foraging was the most prevalent type of behavior during the autumn period,accounting for 58.9％ of the diurnal time budget,followed by preening (13.2％),vigilance (9.5％),walking (8.2％),flying (3.5％),resting (3.4％),chirping (2.7％) and other types of behavior (0.6％).展开更多
The protection of migratory birds and their habitats is important to the ecological stability of the Qinghai-Tibet Plateau(QTP).Currently protected areas(PAs)were designed in accordance with species distribution patte...The protection of migratory birds and their habitats is important to the ecological stability of the Qinghai-Tibet Plateau(QTP).Currently protected areas(PAs)were designed in accordance with species distribution patterns under current climatic conditions,thus ignoring climate change will lead to a decrease in the protection efficiency of PAs.In this study,using the flagship species Grus nigricollis,as an example,we used the maximum entropy(MaxEnt)model to simulate the distributions and conservation status of G.nigricollis and optimized the existing PA boundaries.The results showed that(1)suitable habitat-for G.nigricollis accounts for 12.48%of the QTP area,and the PAs established under current climatic conditions cover 17.84%of this suitable habitat area;(2)future climate changes will influence the distribution and quality of G.nigricollis habitats,and the average protection efficiency of the current PAs in four climatic scenarios will decrease from 17.84%to 15.31%;and(3)through optimization,the efficiency of existing PAs can be increased by 0.75 times and reach 28.37%,indicating PA planning must consider not only current climate conditions but also the effects of climate changes.Our results aim to address shortcomings in the conservation efficiency of PAs and provide an example for resolving mismatched PA boundaries and habitat changes for species.展开更多
文摘The Red-crowned Crane (Grus japonensis) is a globally endangered species.Although this species has received much attention by scientists,conservationists and the general public,the continental population of the Red-crowned Crane continues to face serious threats which affect not only its population dynamics but also its breeding and wintering habitats.Habitat loss and deterioration are the main causes of the decline of its population.With the massive loss of habitats in all parts of its range - breeding,stopover and wintering grounds - the cranes have been forced into crops and farmlands where cranes are more vulnerable to human activities,such as poisoning the cranes and conflicts with farmers.From our review of studies done over 30 years,the eastern flyway subpopulation has been stable or slightly increasing and the western flyway subpopulation of the Red-crowned Crane has sharply declined in recent years.The wintering population for the western flyway has declined from over 1100 to less than 500 birds.Not only is the size of the population reduced to less than 50％,but most recently the decline has occurred with frightening speed,by 50-150 birds per winter.The current wintering range for the west flyway is only about 8％ of its extent in the 1980s.Urgent actions for habitat protection,law enforcement and education need to stop the declining trend for this species.
文摘From January to March 2005, the effects of group size on the vigilance behavior of wintering Common Cranes Grus grus were studied at Lashihai Lake, Yunnan Province, China. We used scan sampling to record the group sizes and the number of vigilant individuals in each group, and focal sampling to record the frequency and duration of individual vigilance behavior. Both the vigilance efforts of groups and individuals significantly decreased as group size increased, but when the group size exceeded 30 individuals, the decrease of group vigilance became not significant （P 〉 0. 05）, and the vigilance duration of adult cranes increased （P 〈 0.01 ）. The vigilance frequency of adults increased （P 〈 0.05） when the size exceeded 50 individuals. Presumably, the maximal group size allowing the lowest vigilance for juvenile cranes was larger than that for adults, and the flocks composed of 20 to 30 individuals represented the optimal group size of wintering Common Cranes by considering only the vigilance behavior. Further research should focus on the synthesized effects of various factors.
基金support was provided by the Continental Minerals Corporation
文摘We investigated collisions with power lines by Black-necked Cranes (Grus nigricollis) and Barheaded Geese (Anser indicus) along the Yarlung Tsangpo River in the Tibet Autonomous Region during two winters.Three segments of a 35 kV transmission line were surveyed each winter for injured and dead birds.Injured birds disappeared within five days of their initial detection; most dead birds encountered had been scavenged.We recorded two dead geese on transects and two injured geese and two dead cranes adjacent to transects.We found a higher incidence of bird strikes along power line segments close to roosting and foraging areas.We recommend that power lines,new or old,located in the flight path from nocturnal roosts,near important foraging areas or crossing the mouths of important agricultural valleys should be marked with colored and/or reflecting devices that have been proven to reduce crane and goose collisions.
基金supported by the National Natural Science Foundation of China(Grant no.31172117,31472020)the Graduate Student Innovation Research Projects of Anhui University(YQH100269)
文摘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 wate
文摘We surveyed all known wintering areas of the Black-necked Crane (Grus nigricollis) in Zhigatse Prefecture of the Tibet Autonomous Region during three winters.Our surveys confirm that Zhigatse Prefecture is the most important wintering area for the species,accounting in some years for as much as 39％ of the estimated world population.Counts ranged from a high of 4240 cranes in January 2007 to a low of 2636 in February 2009.Chick recruitment (chicks/100 cranes) ranged from 8.2 (January 2010) to 11.3 (January 2007).The highest concentration of cranes during all three surveys occurred on the 60 km stretch of the Yarlung Tsangpo (River) between Lhaze and Phuntsoling.To evaluate potential impacts of the Xietongmen Copper Mine,we monitored wintering crane numbers prior to mine installation in an intensive study area located between the Shab Chu Valley and the city of Zhigatse.Our surveys recorded on average 820 ± 83 cranes (SE; n =8) in this area.With the installation of the mine at a location ～50 km west of Zhigatse,increased traffic and development on the north side of the Yarlung River will likely result in a shift in crane distribution away from the north side,to nearby suitable habitats.Based on our survey results,we recommend three areas hosting high numbers of cranes in the vicinity of the mine be added to the Yarlung Tsangpo Middle Reaches Black- necked Crane Nature Reserve.These areas are Nierixiong and Jiaqingze Villages in Nierixiong Xiang and the Shab Chu Valley.
基金financially supported by the Fundamental Research Funds for the Central Universities(No.2572014CA05and DL12EA04)National Natural Science Foundation of China(No.31401978 and 31070345)+1 种基金China Postdoctoral Science Foundation(No.2011M500631)Heilongjiang Postdoctoral Foundation(No.520-415268)
文摘White-naped crane （Grus vipio） is a globally threatened spe- cies. It is very important to analyze its nest site selection in circum- stances where there are multiple disturbances, and also helpful to accu- mulate valuable information about this threatened species and supply scientific suggestions for conservation and management. We studied nest site selection and the effects of environmental variables on nesting habits of white-naped crane at Zhalong National Nature Reserve, Qiqihar City, Heilongiiang, China, during March-May of 2002-2008. White-naped crane responded and adapted to changes in the quality of the spatial environments of landscape and microhabitat under multiple environ- mental disturbances. Nest site selection included two scales and two choices, namely the choice of nest site habitat type within the macro-habitat scale and nest site micro-habitat selection within the mi- cro-habitat scale. Nest sites were recorded only in reed marshes. The choice of nest site micro-habitat included three basic elements and six factors, namely incubation element （nest parameters factor, incubation temperature factor and incubation humidity factor）, safety element （pro- tection factor and concealment factor）, and food element （water factor）. Water, remnant reed clusters, and fire were major resource management challenges during the breeding period for the white-naped crane in this Reserve.
基金supported by the National Natural Science Foundation of China (Grant No 31172117)the Anhui Academic and Technical Leaders Fund
文摘The Hooded Crane (Grus monacha) is a waterbird wintering in the wetlands of the middle and lower reaches of the Yangtze River, China. The gradual habitat loss resulting from wetland degradation may have posed negative effects on the structure of our wintering populations. For its effective protection, it is important to conduct an intensive study on the genetic structure of this population. A total of 221 faecal samples, nine feather samples and four muscle samples of Hooded Cranes from four wintering populations, i.e., from Caizi Lake and Shengjin Lake in Anhui, Poyang Lake in Jiangxi and Chongming Dongtan in Shanghai, were collected for this study. Full-length 1103–1104 bp mtDNA D-loop sequences from 72 samples were amplified using PCR. Based on our amplified D-loop sequences and the sequences of two individual birds obtained from GenBank (AB017625 and AB023813), we analyzed the genetic structure of these four wintering Hooded Crane populations. Twenty six variable sites were found among 72 target sequences in the four wintering populations and 23 haplotypes were defined. Genetic diversity analyses showed that the haplotype diversity of Hooded Cranes was 0.823 ± 0.042 with a nucleotide diversity of 0.00157 ± 0.00021. The FST values of the four populations show that there is no significant genetic differentiation among the populations of Hooded Cranes wintering in the middle and lower reaches of the Yangtze River. Tajima’s D and Fu’s tests suggest that the Hooded Crane populations may have experienced population expansion in their evolutionary history.
基金partly funded by the German Ornithologists’Society(DO-G)。
文摘Facing climate and land use change,a species’ability to successfully adapt to changing environments is crucial for its survival.Extensive drainage and intensification of agriculture and forestry set wetlands and associated species at risk of population declines.The population of Common Cranes(Grus grus)has experienced considerable fluctuations over the last century.Despite increasing population numbers,hatching success seemed to have decreased over the last years.The aim of this study was to identify factors influencing hatching success and nest survival of Common Cranes based on analyses of long-term individual-based monitoring data from northeastern Germany and evaluate the species ability to adapt to changing environments.Hatching success decreased over the course of the study period from 0.75 to 0.55.Surprisingly,nest survival and hatching success did not vary across different nesting habitats,whereas factors such as female age,timing of nest initiation and breeding pair density were found to have significant effects on hatching success.Older females showed higher hatching success,even though the proportion of unhatched eggs was highest in females aged 20 years or older.Early nest initiation had a positive effect on hatching success.Water levels are more favorable early in the nesting season,whereas increasing evaporation with time causes water levels to decrease,granting easier access for predators.Independently of female age,hatching success decreased with increasing numbers of breeding pairs within a 2-km radius around a nesting site.High population densities intensify competition for resources and promote intraspecific interactions,affecting reproductive outcome negatively.This study gives first insights into mechanisms behind population regulation in Common Cranes,highlighting the importance of population dynamics and individual features.We suggest to further investigate density dependent effects including landscape and habitat features as well as reproductive success in terms of chick survival,since s
文摘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.
文摘Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. The result sho wed that the influence from human activities on the wetland habitat of red-crow ned cranes was prominent with the development of oil and agricultural exploitati on, and the habitat pattern of red-crowned cranes had been obviously changed by the human disturbance during the ten years. The areas with high Spatial Diversi ty values (SD≥0.65) and that with mid-high values (0.5≤SD< 0.65), which const ituted the main part of suitable habitat of red-crowned cranes,had reduced to 9142ha and 5576ha respectively, with the shrinking of natural land cover, such a s reed and Suaeda community. The habitat pattern became more fragmented, which w as caused by roads and wells during oil exploration. It was indicated that the s uitability and quality of habitat for red-crowned cranes in the Liaohe Delta we re degraded in the last decade. The results also showed that diversity index cou ld reflect the habitat suitability of red-crowned cranes quantitatively and des cribe the spatial pattern of the habitat explicitly. This study will provide a s cientific basis for habitat protection of red-crowned cranes and other rare spe cies in wetlands.
文摘Through scanning electron microscope, various trpes of feathers in various parts of red-crown crane--a kind of rare and precious bird were observed micrographically. It was shown in the result that in different type of feather, the barbules show a great variation in their morphology and structure. This observation can be a basic reference for the taxonomy using the feather structure and the study of systematic relationship.
文摘Semen characteristics of naturally fertile pairs and their correlation with fertility of eggs in Florida sandhill crane (Grus canadensis pratensis) were examined. Six pairs were used in this experiment, and all of them that had bred before were housed in open individual pens. These pairs were isolated physically each other but not visually and audibly. Semen was collected twice (Tuesday morning and Friday afternoon) from February 26 to June 4, 1993. The standard methods at Patuxent Wildlife Research Center were used collecting and evaluating the semen and spermatozoa. and incubating the eggs. There were statistically individual variations (p<0.05) about successful collecting attempts, semen volume, semen concentration, spermatozoon’s motility,spermatozoon’s number per collection, live spermatozoon’s number, male’s response to semen collection, and morphology of spermatozoa except the giant cell. There was a significantly (p<0.05, correlation coefficient was (0.73 or (1 .00) negative correlation between fertility of eggs and the multiple value of semen (sperm) characteristics of naturally fertile pairs in Florida sandhill crane.
基金prepared with assistance form the Russian Fund for Basic Research,project10-06-00060athe World Wide Fund for Nature
文摘The Trans-Baikal geographical region is located in southeastern Siberia, Russia, east towards Lake Baikal and include the Daurian steppes. The steppes provide important habitats for several species of cranes, including the Red-crowned Crane (Grus japonensis). I have studied the cranes in the area since 1988. The Red-crowned Crane mainly occurs in the Torey Depression (Torey Lake) and the Argun River, which represent the far western edge of the breeding area for the continental population of the Red-crowned Crane. There are some scattering records of the cranes in the Torey Depression from before 1990. The birds appeared regularly and bred from 2002–2007 at Torey Lake. There have been no records since 2008 due to the fact that the wetlands have dried out during the regional climate cycle in the Torey Depression. Three or four individual Red-crowned Cranes have been sighted in Argun in the early 2000’s and then the numbers increased steadily until 2004. At the highest peak in 2004, there were at least 30 pairs of the cranes breeding in the wetlands of the river floodplain. Since then, with the reduced water flow in the Argun River and more and more wetlands drying out, the Red-crowned Crane population decreased dramatically to four or seven territories. The cranes are facing serious threats in the Argun River, such as frequent spring fires, poaching and water pollution. We need to unify efforts from both the Russian and Chinese sides to protect the cranes and their wetland habitat in the area.
基金supported by the National Natural Science Foundation of China(No.31272291,30970340)the Hong Kong Bird Watching Society China Conservation Fund and the Management Bureau of Altun Mountain Natural Reserve
文摘The Black-necked Crane (Grus nigricollis) is an endemic species of the Qinghai-Tibetan Plateau,with its population in Xinjiang largely found in the Kunlun and Altun mountain regions.A survey of the distribution,population dynamics,flock size and behavior was conducted in Altun Mountain National Natural Reserve from September to November 2011.We investigated the size and distribution of its population in this area with a sample spot survey and by direct counting.We found Black-necked Cranes on the wetlands of Wuzunxiaoer,Yusup Aleksei,Yaziquan,Qimantag,Tula Ranch and elsewhere,where we recorded 126 individual birds of the species in Yixiekepati (37° 15′-37°23′N,90°11′-90°20′E,elevation 3903 m),the largest population we have observed in this area.In the reserve,the population consists of about 180-200 birds.Combined with previous records,we conclude that more than 260 Black-necked Cranes live in Xinjiang.Cranes gathered conspicuously in the middle of October where the highest number of birds appeared on 29 October.All of the cranes had migrated out of this area by 6 November.Time budgets and diurnal behavior rhythms of Blacknecked Cranes were observed in the Yixiekepati wetland at daylight (from 06:00 to 18:00).Foraging was the most prevalent type of behavior during the autumn period,accounting for 58.9％ of the diurnal time budget,followed by preening (13.2％),vigilance (9.5％),walking (8.2％),flying (3.5％),resting (3.4％),chirping (2.7％) and other types of behavior (0.6％).
基金This research was funded by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(Grant No.2019QZKK0307)the National Natural Science Foundation of China(Grant Nos.41925005 and 41701051)the Special Program of Research Center for Ecoenvironmental Sciences,at the Chinese Academy of Sciences(RCEES-TDZ-2021-11).
文摘The protection of migratory birds and their habitats is important to the ecological stability of the Qinghai-Tibet Plateau(QTP).Currently protected areas(PAs)were designed in accordance with species distribution patterns under current climatic conditions,thus ignoring climate change will lead to a decrease in the protection efficiency of PAs.In this study,using the flagship species Grus nigricollis,as an example,we used the maximum entropy(MaxEnt)model to simulate the distributions and conservation status of G.nigricollis and optimized the existing PA boundaries.The results showed that(1)suitable habitat-for G.nigricollis accounts for 12.48%of the QTP area,and the PAs established under current climatic conditions cover 17.84%of this suitable habitat area;(2)future climate changes will influence the distribution and quality of G.nigricollis habitats,and the average protection efficiency of the current PAs in four climatic scenarios will decrease from 17.84%to 15.31%;and(3)through optimization,the efficiency of existing PAs can be increased by 0.75 times and reach 28.37%,indicating PA planning must consider not only current climate conditions but also the effects of climate changes.Our results aim to address shortcomings in the conservation efficiency of PAs and provide an example for resolving mismatched PA boundaries and habitat changes for species.
