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 Hood...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.展开更多
Great Bustards(Otis tarda dybowskii)are one of the world’s heaviest flying birds,occupying grassland habitats in Eastern Asia.Our study is located at the most eastern Chinese wintering site in Cangzhou,Hebei Province...Great Bustards(Otis tarda dybowskii)are one of the world’s heaviest flying birds,occupying grassland habitats in Eastern Asia.Our study is located at the most eastern Chinese wintering site in Cangzhou,Hebei Province,where approximately 100 individuals are concentrated in a small area(17.53 km2).Solid information is still lacking about the wintering areas for this subspecies in its eastern range and specifically for China.The study area consists of intensely used farmland in proximity to humans and is lacking conservation areas and wild,open fields.Here,we present our results from two years of field data collection on habitat selection.We choose a machine learning model approach based on a rapid assessment methodology for the winter habitat of the Great Bustard.It is based on a spatial analysis of the best available environmental data,which were collected relatively quickly.These relatively new methods in ecology are based on an ensemble of decision trees and include algorithms such as TreeNet,Random Forest and CART used in parallel.In this study,we collected bustard droppings(presence only)from 48 locations between December 2011 and January 2012 and used the sites as training data.Droppings from 23 locations were collected in November 2012,and those sites were used as test data.We used eight environmental variables as predictor layers for the response variable of bustard presence/availability.We employed a Geographic Information System(ArcGIS 10.1and Geospatial Modelling Environment)and Google Earth.Compared with the other three models,we found that predictions from Random Forest obtained a significant difference between presence and absence.According to this model,the three most important factors for wintering Great Bustards are distance to residential area,distance to water pools,and farmland area.Our model shows that wintering Great Bustards prefer locations that are over 400 m away from residential areas,within 900 m of water pools and on areas of farmland smaller than 0.5 km2.We think we can apply our analysis to Great Bustard management in our study area and the adjacent region and that this work sets a baseline for future research.展开更多
The loss of biodiversity from urbanized areas is a major environmental problem challenging policy-makers throughout the world.Solutions to this problem are urgently required in China.We carried out a case study of win...The loss of biodiversity from urbanized areas is a major environmental problem challenging policy-makers throughout the world.Solutions to this problem are urgently required in China.We carried out a case study of wintering long-eared owls(Asio otus)and their main prey to illustrate the negative effects of urbanization combined with ineffective conservation of biodiversity in Beijing.Field monitoring of owl numbers at two roosting sites from 2004 to 2012 showed that the owl population had fallen rapidly in metropolitan Beijing.Analysis of pellet contents identified only seven individuals of two species of shrew.The majority of mammalian prey comprised four bat and seven rodent species,making up 29.3%and 29.5%of the prey items,respectively.Prey composition varied significantly among years at the two sample sites.At the urban site the consumption of bats and rodents declined gradually over time,while predation on birds increased.In contrast,at the suburban site the prey composition showed an overall decrease in the number of bats,a sharp increase and a subsequent decrease in bird prey,and the number of rodent prey fell to a low point.Rapid development of real estate and inadequate greenfield management in city parks resulted in negative effects on the bird and small mammal habitat of urban areas in Beijing.We suggest that measures to conserve biodiversity should be integrated into future urban planning to maintain China’s rich biodiversity while also achieving sustainable economic development.展开更多
Tens of thousands of demoiselle cranes’crossing the Himalayas to the Indian subcontinent have been reported for decades,but their exact spring migration route remained a mystery until our previous study found they ma...Tens of thousands of demoiselle cranes’crossing the Himalayas to the Indian subcontinent have been reported for decades,but their exact spring migration route remained a mystery until our previous study found they made a detour in spring along the western edge of the Himalayas and crossed the Mongolian Plateau to their breeding areas based on satellite telemetry of 3 birds.To corroborate the loop migration pattern and explore whether demoiselle crane’s loop migration route is shaped by time-and energy-minimization strategies in spring and autumn and how the temporal and spatial variation of environmental conditions contribute to crane’s selection of migration routes,we tracked 11 satellite-tagged demoiselle cranes from their breeding area in China and Russia,simulated 2 pseudo migration routes,and then compared the environmental conditions,time,and energy cost between true and pseudo routes in the same season.Results show that demoiselles’spring migration obeyed time-minimization hypothesis,avoiding the colder Qinghai-Tibet Plateau,benefited by abundant food and higher thermal and orographic uplift along the route;autumn migration follows energy-minimization hypothesis with the shorter route.Our research will contribute to uncover the mechanical reasons why demoiselle crane avoids crossing the giant barrier of the Himalayas in spring,and shapes a loop migration route.展开更多
基金funded by the National Natural Science Foundation of China(Grant No.31570532)
文摘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.
基金supported by the National Forestry Bureau of China(1105-LYSJWT-113)
文摘Great Bustards(Otis tarda dybowskii)are one of the world’s heaviest flying birds,occupying grassland habitats in Eastern Asia.Our study is located at the most eastern Chinese wintering site in Cangzhou,Hebei Province,where approximately 100 individuals are concentrated in a small area(17.53 km2).Solid information is still lacking about the wintering areas for this subspecies in its eastern range and specifically for China.The study area consists of intensely used farmland in proximity to humans and is lacking conservation areas and wild,open fields.Here,we present our results from two years of field data collection on habitat selection.We choose a machine learning model approach based on a rapid assessment methodology for the winter habitat of the Great Bustard.It is based on a spatial analysis of the best available environmental data,which were collected relatively quickly.These relatively new methods in ecology are based on an ensemble of decision trees and include algorithms such as TreeNet,Random Forest and CART used in parallel.In this study,we collected bustard droppings(presence only)from 48 locations between December 2011 and January 2012 and used the sites as training data.Droppings from 23 locations were collected in November 2012,and those sites were used as test data.We used eight environmental variables as predictor layers for the response variable of bustard presence/availability.We employed a Geographic Information System(ArcGIS 10.1and Geospatial Modelling Environment)and Google Earth.Compared with the other three models,we found that predictions from Random Forest obtained a significant difference between presence and absence.According to this model,the three most important factors for wintering Great Bustards are distance to residential area,distance to water pools,and farmland area.Our model shows that wintering Great Bustards prefer locations that are over 400 m away from residential areas,within 900 m of water pools and on areas of farmland smaller than 0.5 km2.We think we can apply our analysis to Great Bustard management in our study area and the adjacent region and that this work sets a baseline for future research.
基金This work was funded by the National Science Foundation of China for National Biological Science Base(J1103516).We thank the following postgraduate students from our research group for collecting and analyzing owl pellets throughout the years of this study:BM Peng,LJ Zhang,XJ Li,L Yuan,AM Wang and PL Yu.We appreciate helpful comments and English proofreading of the manuscript by Y.Wang.of the Alabama Agriculture and Machinery University.We declare that all sources of funding have been acknowledged and that there are no conflicts of interest regarding financial support.
文摘The loss of biodiversity from urbanized areas is a major environmental problem challenging policy-makers throughout the world.Solutions to this problem are urgently required in China.We carried out a case study of wintering long-eared owls(Asio otus)and their main prey to illustrate the negative effects of urbanization combined with ineffective conservation of biodiversity in Beijing.Field monitoring of owl numbers at two roosting sites from 2004 to 2012 showed that the owl population had fallen rapidly in metropolitan Beijing.Analysis of pellet contents identified only seven individuals of two species of shrew.The majority of mammalian prey comprised four bat and seven rodent species,making up 29.3%and 29.5%of the prey items,respectively.Prey composition varied significantly among years at the two sample sites.At the urban site the consumption of bats and rodents declined gradually over time,while predation on birds increased.In contrast,at the suburban site the prey composition showed an overall decrease in the number of bats,a sharp increase and a subsequent decrease in bird prey,and the number of rodent prey fell to a low point.Rapid development of real estate and inadequate greenfield management in city parks resulted in negative effects on the bird and small mammal habitat of urban areas in Beijing.We suggest that measures to conserve biodiversity should be integrated into future urban planning to maintain China’s rich biodiversity while also achieving sustainable economic development.
基金funding is from the National Natural Science Foundation of China awarded to Yumin Guo(grant no.31770573 and no.31570532)supported by Alliance of International Science Organization(ANSO)(Project ID:ANSO-CR-KP-2020-08)。
文摘Tens of thousands of demoiselle cranes’crossing the Himalayas to the Indian subcontinent have been reported for decades,but their exact spring migration route remained a mystery until our previous study found they made a detour in spring along the western edge of the Himalayas and crossed the Mongolian Plateau to their breeding areas based on satellite telemetry of 3 birds.To corroborate the loop migration pattern and explore whether demoiselle crane’s loop migration route is shaped by time-and energy-minimization strategies in spring and autumn and how the temporal and spatial variation of environmental conditions contribute to crane’s selection of migration routes,we tracked 11 satellite-tagged demoiselle cranes from their breeding area in China and Russia,simulated 2 pseudo migration routes,and then compared the environmental conditions,time,and energy cost between true and pseudo routes in the same season.Results show that demoiselles’spring migration obeyed time-minimization hypothesis,avoiding the colder Qinghai-Tibet Plateau,benefited by abundant food and higher thermal and orographic uplift along the route;autumn migration follows energy-minimization hypothesis with the shorter route.Our research will contribute to uncover the mechanical reasons why demoiselle crane avoids crossing the giant barrier of the Himalayas in spring,and shapes a loop migration route.