The migratory nature of avian species is well known not only to researchers but also to the general public,becoming engrained in cultural traditions and even children's fairy tales.However,our understanding of the...The migratory nature of avian species is well known not only to researchers but also to the general public,becoming engrained in cultural traditions and even children's fairy tales.However,our understanding of these charismatic behaviors made great strides in the 1990s with the advent of small,light-weighted satellite transmitters capable of longterm tracking(Argos,2016).The emergence of this new technology made it possible to track a broader range of species at higher resolution than ever before.In turn,this data enabled detailed understanding of individual avian behavior and habitats,including transboundary migration routes.展开更多
The publisher regrets that the Appendix A.Supplementary data was not updated as per author and editor’s request.The publisher would like to apologise for any inconvenience caused.
Ecological barriers present significant challenges to bird migration by limiting the availability of stopover sites and shelters. The Qinghai-Tibet Plateau, a major migratory barrier located in higher latitude Central...Ecological barriers present significant challenges to bird migration by limiting the availability of stopover sites and shelters. The Qinghai-Tibet Plateau, a major migratory barrier located in higher latitude Central Asia, exerts a substantial influence on avian migration patterns. Species traversing such ecological barriers may adopt multiple optimal routes, which can contribute to the formation of migratory divides. From 2018 to 2021, the migration routes of 13 adult Common Cuckoos (Cuculus canorus) breeding in the north of the Qinghai-Tibet Plateau were tracked using satellite transmitters. We found Common Cuckoos have two primary migration routes: western and eastern, respectively following western and eastern edges of the Qinghai-Tibet plateau. The eastern and western routes are likely the optimal routes for the Central Asian Common Cuckoos population to navigate the Qinghai-Tibet Plateau. Furthermore, two individuals exhibited intermediate migration routes, suggesting attempted traverses of the Qinghai-Tibet Plateau, although neither completed the migration. These intermediate routes may indicate migratory behavior influenced by hybridization between eastern and western populations or migratory flexibility. Common Cuckoos exhibit significantly faster migration speed, flight speed, and shorter stopover durations during spring compared to autumn. The observed seasonal differences in migration behavior support birds following time-minimization strategies during spring migration. These results revealed the diverse migration routes of Common Cuckoos shaped by the Qinghai-Tibet Plateau and seasonal variation in migration patterns.展开更多
By recording nocturnally migrating passerines with tracking radar we have investigated how coastlines affect the migrants＇ flight paths. Birds could use coastlines as an orientation aid or as a reference cue to compe...By recording nocturnally migrating passerines with tracking radar we have investigated how coastlines affect the migrants＇ flight paths. Birds could use coastlines as an orientation aid or as a reference cue to compensate for wind drift while mi- grating. However, on the small scale of Falsterbo Peninsula in southern Sweden, we found very little effect of coastlines on migrants flight paths, irrespective of altitude. We tracked 2 930 migrants in three autumn and two spring seasons, at altitudes from 60 up to 3 000 meters. We compared tracks of migrants flying in three different areas, which correspond to the three main coastlines, and can demonstrate that the orientation of the tracks did not differ in a way consistent with the coastlines between the areas in autumn, and showed only a slight effect in spring. This is in accordance with earlier infrared device monitoring in Falsterbo, but contrary to earlier visual observations. It supports the view of nocturnally migrating passerines as mainly broad-front migrants. Even though the coastlines on the scale of the peninsula affected the flight paths very little, it is possible that the coastline has an effect on a larger regional scale, by migrants avoiding long sea crossings and thereby being funneled towards the peninsula, but this remains to be investigated [Current Zoology 60 （5）： 660-669, 2014].展开更多
Background: Weather effects on bird migration are well-studied among Passerines moving from Europe to Africa or within the American flyway systems. However, little is known about the weather impact on songbirds migrat...Background: Weather effects on bird migration are well-studied among Passerines moving from Europe to Africa or within the American flyway systems. However, little is known about the weather impact on songbirds migrating along the East Asian flyway. Our study aims to describe the effects of various weather elements on the migration of four species of leaf warblers by using bird ringing data from a stopover site in Far East Russia.Methods: We determined the migration periods for each species and included maximum temperature, precipitation, air pressure, wind speed and wind direction in general linearized mixed models to predict the number of migrating birds.Results: We found strong impacts of weather variables on the number of trapped warblers during spring and autumn migration. Preferred or avoided weather conditions were similar among the studied species. All species seem to migrate preferably during warm, calm days without precipitation. A positive effect of tail winds was only confirmed in autumn, but in spring, most birds were trapped during crosswinds(eastern or western winds).Conclusion: The studied species might exhibit a loop migration, leading to a more longitudinal(from east to west) migration pattern in our study area during spring. Relationships between weather variables and the number of migrating individuals were much stronger during autumn. We argue that birds during spring migration would continue migration under sub-optimal conditions, as a result of strong competition to arrive earliest on their breeding grounds.展开更多
Multi-manned assembly line,which is broadly utilized to assemble high volume products such as automobiles and trucks,allows a group of workers to assemble different tasks simultaneously in a multi-manned workstation.T...Multi-manned assembly line,which is broadly utilized to assemble high volume products such as automobiles and trucks,allows a group of workers to assemble different tasks simultaneously in a multi-manned workstation.This additional characteristic of parallel operators increases the complexity of the traditional NP-hard assembly line balancing problem.Hence,this paper formulates the Type-I multi-manned assembly line balancing problem to minimize the total number of workstations and operators,and develops an efficient migrating birds optimization algorithm embedded into an idle time reduction method.In this algorithm,a new decoding mechanism is proposed which reduces the sequence-dependent idle time by some task assignment rules;three effective neighborhoods are developed to make refinement of existing solutions in the bird improvement phases;and temperature acceptance and competitive mechanism are employed to avoid being trapped in the local optimum.Comparison experiments suggest that the new decoding and improvements are effective and the proposed algorithm outperforms the compared algorithms.展开更多
FSSP is a typical NP-Hard problem which is desired to be minimum makespan. This study consid- ers Migrating Birds Optimization (MBO) which is metaheuristic approach for the solution of Flow Shop Sequencing Problem (FS...FSSP is a typical NP-Hard problem which is desired to be minimum makespan. This study consid- ers Migrating Birds Optimization (MBO) which is metaheuristic approach for the solution of Flow Shop Sequencing Problem (FSSP). As the basic MBO algorithm is designed for discrete problems. The performance of basic MBO algorithm is tested via some FSSP data sets exist in literature. Obtained results are compared with optimal results of related data sets.展开更多
Background: Ring wear and loss may have important consequences for mark-recapture studies that aim to estimate survival trends. Our study quantifies the rates of wear and loss from a long-running colour-ringing projec...Background: Ring wear and loss may have important consequences for mark-recapture studies that aim to estimate survival trends. Our study quantifies the rates of wear and loss from a long-running colour-ringing project of the Eurasian Oystercatcher (Haematopus ostralegus) in the Netherlands. Methods: Our analysis included 8909 colour-ringed oystercatchers with 118,071 resightings, predominantly ringed and observed by citizen scientists. We quantified how ring wear and loss may vary with ring colour and age, and how this may impact resighting probabilities. We then determined how ring loss may impact survival estimates and resighting probabilities of mark-recapture models by simulating four scenarios of how citizen scientists may resight and report birds with lost colour rings. Results: Annual rates of colour ring loss averaged 2.5% compared with 1% for ring wear, but lost rings also had a higher reporting probability (31.2%) than worn rings (10.3%). Lost rings may not directly impact survival estimates since 50% of oystercatchers with lost rings could still be uniquely identified. Ring wear and loss rapidly increased between 10 and 15 years after ringing. Rates of ring loss were comparable amongst ring colours, but the wear rate appeared higher for red and white rings compared to other colours. Rates of ring wear and loss varied significantly amongst different regions in our study, which were characterised as having different habitat features. Differential rates of ring wear may have important implications for studies conducted over large geographical scales or of multiple species. Conclusions: Based on simulations of ring loss in our population, estimates of apparent survival may be 0.3–1.2% lower whilst the impact of ring wear was deemed even lower. We developed a table of recommendations containing advice for ring fitting, data collection, study design, and mark-recapture analyses, so that future colour-ringing studies can benefit from our experiences in collecting and analysing data of ring wear and loss through citizen science.展开更多
Advanced satellite tracking technologies provide biologists with long-term location sequence data to understand movement of wild birds then to find explicit correlation between dynamics of migratory birds and the spre...Advanced satellite tracking technologies provide biologists with long-term location sequence data to understand movement of wild birds then to find explicit correlation between dynamics of migratory birds and the spread of avian influenza. In this paper, we propose a hierarchical clustering algorithm based on a recursive grid partition and kernel density estimation （KDE） to hierarchically identify wild bird habitats with different densities. We hierarchically cluster the GPS data by taking into account the following observations： 1） the habitat variation on a variety of geospatial scales; 2） the spatial variation of the activity patterns of birds in different stages of the migration cycle. In addition, we measure the site fidelity of wild birds based on clustering. To assess effectiveness, we have evaluated our system using a large-scale GPS dataset collected from 59 birds over three years. As a result, our approach can identify the hierarchical habitats and distribution of wild birds more efficiently than several commonly used algorithms such as DBSCAN and DENCLUE.展开更多
Background:In China since the first human infection of avian influenza A(H7N9)virus was identified in 2013,it has caused serious public health concerns due to its wide spread and high mortality rate.Evidence shows tha...Background:In China since the first human infection of avian influenza A(H7N9)virus was identified in 2013,it has caused serious public health concerns due to its wide spread and high mortality rate.Evidence shows that bird migration plays an essential role in global spread of avian influenza viruses.Accordingly,in this paper,we aim to identify key bird species and geographical hotspots that are relevant to the transmission of avian influenza A(H7N9)virus in China.Methods:We first conducted phylogenetic analysis on 626 viral sequences of avian influenza A(H7N9)virus isolated in chicken,which were collected from the Global Initiative on Sharing All Influenza Data(GISAID),to reveal geographical spread and molecular evolution of the virus in China.Then,we adopted the cross correlation function(CCF)to explore the relationship between the identified influenza A(H7N9)cases and the spatiotemporal distribution of migratory birds.Here,the spatiotemporal distribution of bird species was generated based on bird observation data collected from China Bird Reports,which consists of 157272 observation records about 1145 bird species.Finally,we employed a kernel density estimator to identify geographical hotspots of bird habitat/stopover that are relevant to the influenza A(H7N9)infections.Results:Phylogenetic analysis reveals the evolutionary and geographical patterns of influenza A(H7N9)infections,where cases in the same or nearby municipality/provinces are clustered together with small evolutionary differences.Moreover,three epidemic waves in chicken along the East Asian-Australasian flyway in China are distinguished from the phylogenetic tree.The CCF analysis identifies possible migratory bird species that are relevant to the influenza A(H7N9)infections in Shanghai,Jiangsu,Zhejiang,Fujian,Jiangxi,and Guangdong in China,where the six municipality/provinces account for 91.2%of the total number of isolated H7N9 cases in chicken in GISAID.Based on the spatial distribution of identified bird species,geographical hotspots are further estimated and illustrated within these typical municipality/provinces.Conclusions:In this paper,we have identified key bird species and geographical hotspots that are relevant to the spread of influenza A(H7N9)virus.The results and findings could provide sentinel signal and evidence for active surveillance,as well as strategic control of influenza A(H7N9)transmission in China.展开更多
Migratory divides,where individuals from distinct breeding populations within a species exhibit divergent migratory routes and strategies,play a critical role in shaping avian ecology and evolution.These divides can d...Migratory divides,where individuals from distinct breeding populations within a species exhibit divergent migratory routes and strategies,play a critical role in shaping avian ecology and evolution.These divides can drive intraspecific genetic divergence and promote reproductive isolation,potentially leading to population differentiation and speciation.Understanding the migration strategies of populations utilizing distinct flyways is essential not only for elucidating the mechanisms underlying migration patterns but also for informing effective species conservation efforts.From 2014 to 2023,we used satellite tracking to monitor the migration patterns of 87 White-naped Cranes(Antigone vipio)from the species'two breeding populations—western(Mongolia)and eastern(Songnen Plain,China).We delineated their migratory routes,quantified key migration parameters,and identified their population-and season-specific differences in migratory strategies.Our results indicate that the Greater Khingan Mountains and the Bohai-Yellow Sea formed a distinct migratory barrier separating the eastern and western populations.Significant differences in migration strategies were observed between populations and seasons.The western population adopts a"longer-distance,slower-speed,more-stopover"strategy,while the eastern population employs a"shorter-distance,higher-speed,fewer-stopover"strategy.Our study identifies the migratory divides between the two populations of White-naped Cranes and highlights the importance of migratory divides in shaping distinct migration strategies.These findings enhance our understanding of the factors driving population-specific migration strategies and provide a foundation for tailored conservation efforts for these populations.展开更多
芝加哥是美国的一个重要城市,德莱塞的长篇小说Sister Carrie的背景城市,一百年之前早已喧嚣繁华。现在更是高楼林立。岂料,那里夜间灯火通明的高楼竟然成了无数候鸟的葬身之地！候鸟竟然和海里的鱼一样,具有趋光性。为此,芝加哥采取了...芝加哥是美国的一个重要城市,德莱塞的长篇小说Sister Carrie的背景城市,一百年之前早已喧嚣繁华。现在更是高楼林立。岂料,那里夜间灯火通明的高楼竟然成了无数候鸟的葬身之地！候鸟竟然和海里的鱼一样,具有趋光性。为此,芝加哥采取了高楼“减亮”等项措施,以拯救候鸟。本文文字信息丰富,优美通俗,值得细学。比如: We're not enduring the same energy crisis that's going on in California, butbuilding owners might be able to save a few pennies while performing a good deed。 本句信息:California(正遭受)energy crisis。 本句修辞:to save a few pennies(典型的understatement,低调) 本句句型:periodic sentence(圆周句)】展开更多
Background In March 2013,human cases of infection with a novel A （H7N9） influenza virus emerged in China.The epidemic spread quickly and as of 6 May 2013,there were 129 confirmed cases.The purpose of this study was ...Background In March 2013,human cases of infection with a novel A （H7N9） influenza virus emerged in China.The epidemic spread quickly and as of 6 May 2013,there were 129 confirmed cases.The purpose of this study was to analyze the epidemiology of the confirmed cases,determine the impacts of bird migration and temperature changes on the H7N9 epidemic,predict the future trends of the epidemic,explore the response patterns of the government and propose preventive suggestions.Methods The geographic,temporal and population distribution of all cases reported up to 6 May 2013 were described from available records.Risk assessment standard was established by analysing the temperature and relative humidity records during the period of extensive outbreak in three epidemic regions in eastern China,including Shanghai,Zhejiang and Jiangsu provinces.Risk assessment maps were created by combining the bird migration routes in eastern China with the monthly average temperatures from May 1993 to December 2012 nationwide.Results Among the confirmed cases,there were more men than women,and 50.4％ were elderly adults （age ＞61 years）.The major demographic groups were retirees and farmers.The temperature on the days of disease onset was concentrated in the range of 9℃-19℃; we defined 9℃-19℃ as the high-risk temperature range,0℃-9℃ or 19℃-25℃ as medium risk and ＜0℃ or ＞25℃ as low risk.The relative humidity on the days of disease onset ranged widely from 25％ to 99％,but did not correlate with the incidence of infection.Based on the temperature analysis and the eastern bird migration routes,we predicted that after May,the high-risk region would move to the northeast and inland,while after September,it would move back to north China.Conclusions Temperature and bird migration strongly influence the spread of the H7N9 virus.In order to control the H7N9 epidemic effectively,Chinese authorities should strengthen the surveillance of migrating birds,increase poultry and environmental sampling,improve live poultry selling and husbandry patterns and move from a ＂passive response pattern＂to an ＂active response pattern＂ in focused preventive measures.展开更多
Lyme disease,a typical tick-borne disease,imposes increasing global public health challenges.A growing body of theoretical models have been proposed to better understand various factors determining the disease risk,wh...Lyme disease,a typical tick-borne disease,imposes increasing global public health challenges.A growing body of theoretical models have been proposed to better understand various factors determining the disease risk,which not only enrich our understanding on the ecological cycle of disease transmission but also promote new theoretical developments on model formulation,analysis and simulation.In this paper,we provide a review about the models and results we have obtained recently on modeling and analyzing Lyme disease transmission,with the purpose to highlight various aspects in the ecological cycle of disease transmission to be incorporated,including the growth of ticks with different stages in the life cycle,the seasonality,host diversity,spatial disease pattern due to host short distance movement and bird migration,co-infection with other tick-borne pathogens,and climate change impact.展开更多
文摘The migratory nature of avian species is well known not only to researchers but also to the general public,becoming engrained in cultural traditions and even children's fairy tales.However,our understanding of these charismatic behaviors made great strides in the 1990s with the advent of small,light-weighted satellite transmitters capable of longterm tracking(Argos,2016).The emergence of this new technology made it possible to track a broader range of species at higher resolution than ever before.In turn,this data enabled detailed understanding of individual avian behavior and habitats,including transboundary migration routes.
文摘The publisher regrets that the Appendix A.Supplementary data was not updated as per author and editor’s request.The publisher would like to apologise for any inconvenience caused.
基金supported by the National Natural Science Foundation of China(Grant No.31672296).
文摘Ecological barriers present significant challenges to bird migration by limiting the availability of stopover sites and shelters. The Qinghai-Tibet Plateau, a major migratory barrier located in higher latitude Central Asia, exerts a substantial influence on avian migration patterns. Species traversing such ecological barriers may adopt multiple optimal routes, which can contribute to the formation of migratory divides. From 2018 to 2021, the migration routes of 13 adult Common Cuckoos (Cuculus canorus) breeding in the north of the Qinghai-Tibet Plateau were tracked using satellite transmitters. We found Common Cuckoos have two primary migration routes: western and eastern, respectively following western and eastern edges of the Qinghai-Tibet plateau. The eastern and western routes are likely the optimal routes for the Central Asian Common Cuckoos population to navigate the Qinghai-Tibet Plateau. Furthermore, two individuals exhibited intermediate migration routes, suggesting attempted traverses of the Qinghai-Tibet Plateau, although neither completed the migration. These intermediate routes may indicate migratory behavior influenced by hybridization between eastern and western populations or migratory flexibility. Common Cuckoos exhibit significantly faster migration speed, flight speed, and shorter stopover durations during spring compared to autumn. The observed seasonal differences in migration behavior support birds following time-minimization strategies during spring migration. These results revealed the diverse migration routes of Common Cuckoos shaped by the Qinghai-Tibet Plateau and seasonal variation in migration patterns.
文摘By recording nocturnally migrating passerines with tracking radar we have investigated how coastlines affect the migrants＇ flight paths. Birds could use coastlines as an orientation aid or as a reference cue to compensate for wind drift while mi- grating. However, on the small scale of Falsterbo Peninsula in southern Sweden, we found very little effect of coastlines on migrants flight paths, irrespective of altitude. We tracked 2 930 migrants in three autumn and two spring seasons, at altitudes from 60 up to 3 000 meters. We compared tracks of migrants flying in three different areas, which correspond to the three main coastlines, and can demonstrate that the orientation of the tracks did not differ in a way consistent with the coastlines between the areas in autumn, and showed only a slight effect in spring. This is in accordance with earlier infrared device monitoring in Falsterbo, but contrary to earlier visual observations. It supports the view of nocturnally migrating passerines as mainly broad-front migrants. Even though the coastlines on the scale of the peninsula affected the flight paths very little, it is possible that the coastline has an effect on a larger regional scale, by migrants avoiding long sea crossings and thereby being funneled towards the peninsula, but this remains to be investigated [Current Zoology 60 （5）： 660-669, 2014].
基金supported by the German Ornithologists’Society,the Forderkreis Allgemeine Naturkunde(Biologie)e.V.and the NABU RVE e.VLB’s work was supported by the Campus Hungary Studentship and the Hungarian National Young Talent Studentship
文摘Background: Weather effects on bird migration are well-studied among Passerines moving from Europe to Africa or within the American flyway systems. However, little is known about the weather impact on songbirds migrating along the East Asian flyway. Our study aims to describe the effects of various weather elements on the migration of four species of leaf warblers by using bird ringing data from a stopover site in Far East Russia.Methods: We determined the migration periods for each species and included maximum temperature, precipitation, air pressure, wind speed and wind direction in general linearized mixed models to predict the number of migrating birds.Results: We found strong impacts of weather variables on the number of trapped warblers during spring and autumn migration. Preferred or avoided weather conditions were similar among the studied species. All species seem to migrate preferably during warm, calm days without precipitation. A positive effect of tail winds was only confirmed in autumn, but in spring, most birds were trapped during crosswinds(eastern or western winds).Conclusion: The studied species might exhibit a loop migration, leading to a more longitudinal(from east to west) migration pattern in our study area during spring. Relationships between weather variables and the number of migrating individuals were much stronger during autumn. We argue that birds during spring migration would continue migration under sub-optimal conditions, as a result of strong competition to arrive earliest on their breeding grounds.
基金supported by the National Natural Science Foundation of China(51875421,61803287).
文摘Multi-manned assembly line,which is broadly utilized to assemble high volume products such as automobiles and trucks,allows a group of workers to assemble different tasks simultaneously in a multi-manned workstation.This additional characteristic of parallel operators increases the complexity of the traditional NP-hard assembly line balancing problem.Hence,this paper formulates the Type-I multi-manned assembly line balancing problem to minimize the total number of workstations and operators,and develops an efficient migrating birds optimization algorithm embedded into an idle time reduction method.In this algorithm,a new decoding mechanism is proposed which reduces the sequence-dependent idle time by some task assignment rules;three effective neighborhoods are developed to make refinement of existing solutions in the bird improvement phases;and temperature acceptance and competitive mechanism are employed to avoid being trapped in the local optimum.Comparison experiments suggest that the new decoding and improvements are effective and the proposed algorithm outperforms the compared algorithms.
基金supported by Scientific Research Project of Necmettin Erbakan University
文摘FSSP is a typical NP-Hard problem which is desired to be minimum makespan. This study consid- ers Migrating Birds Optimization (MBO) which is metaheuristic approach for the solution of Flow Shop Sequencing Problem (FSSP). As the basic MBO algorithm is designed for discrete problems. The performance of basic MBO algorithm is tested via some FSSP data sets exist in literature. Obtained results are compared with optimal results of related data sets.
基金supported by the Applied and Engineering Sciences domain,TTW,which is part of the Netherlands Organisation for Scientific Research(NWO)NWO-TTW Grant 14638co-funded by NAM,the Royal Netherlands Air Force,Birdlife Netherlands and Deltares
文摘Background: Ring wear and loss may have important consequences for mark-recapture studies that aim to estimate survival trends. Our study quantifies the rates of wear and loss from a long-running colour-ringing project of the Eurasian Oystercatcher (Haematopus ostralegus) in the Netherlands. Methods: Our analysis included 8909 colour-ringed oystercatchers with 118,071 resightings, predominantly ringed and observed by citizen scientists. We quantified how ring wear and loss may vary with ring colour and age, and how this may impact resighting probabilities. We then determined how ring loss may impact survival estimates and resighting probabilities of mark-recapture models by simulating four scenarios of how citizen scientists may resight and report birds with lost colour rings. Results: Annual rates of colour ring loss averaged 2.5% compared with 1% for ring wear, but lost rings also had a higher reporting probability (31.2%) than worn rings (10.3%). Lost rings may not directly impact survival estimates since 50% of oystercatchers with lost rings could still be uniquely identified. Ring wear and loss rapidly increased between 10 and 15 years after ringing. Rates of ring loss were comparable amongst ring colours, but the wear rate appeared higher for red and white rings compared to other colours. Rates of ring wear and loss varied significantly amongst different regions in our study, which were characterised as having different habitat features. Differential rates of ring wear may have important implications for studies conducted over large geographical scales or of multiple species. Conclusions: Based on simulations of ring loss in our population, estimates of apparent survival may be 0.3–1.2% lower whilst the impact of ring wear was deemed even lower. We developed a table of recommendations containing advice for ring fitting, data collection, study design, and mark-recapture analyses, so that future colour-ringing studies can benefit from our experiences in collecting and analysing data of ring wear and loss through citizen science.
文摘Advanced satellite tracking technologies provide biologists with long-term location sequence data to understand movement of wild birds then to find explicit correlation between dynamics of migratory birds and the spread of avian influenza. In this paper, we propose a hierarchical clustering algorithm based on a recursive grid partition and kernel density estimation （KDE） to hierarchically identify wild bird habitats with different densities. We hierarchically cluster the GPS data by taking into account the following observations： 1） the habitat variation on a variety of geospatial scales; 2） the spatial variation of the activity patterns of birds in different stages of the migration cycle. In addition, we measure the site fidelity of wild birds based on clustering. To assess effectiveness, we have evaluated our system using a large-scale GPS dataset collected from 59 birds over three years. As a result, our approach can identify the hierarchical habitats and distribution of wild birds more efficiently than several commonly used algorithms such as DBSCAN and DENCLUE.
基金This work was supported by the Hong Kong Research Grants Council(RGC/HKBU12202415)the National Natural Science Foundation of China(Grant Nos.81402760,81573261)+2 种基金the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20161563)Computational work was partially supported by Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund(Grant No.U1501501)The funders had no role in study design,data collection and analysis,decision to publish,or preparation of the manuscript。
文摘Background:In China since the first human infection of avian influenza A(H7N9)virus was identified in 2013,it has caused serious public health concerns due to its wide spread and high mortality rate.Evidence shows that bird migration plays an essential role in global spread of avian influenza viruses.Accordingly,in this paper,we aim to identify key bird species and geographical hotspots that are relevant to the transmission of avian influenza A(H7N9)virus in China.Methods:We first conducted phylogenetic analysis on 626 viral sequences of avian influenza A(H7N9)virus isolated in chicken,which were collected from the Global Initiative on Sharing All Influenza Data(GISAID),to reveal geographical spread and molecular evolution of the virus in China.Then,we adopted the cross correlation function(CCF)to explore the relationship between the identified influenza A(H7N9)cases and the spatiotemporal distribution of migratory birds.Here,the spatiotemporal distribution of bird species was generated based on bird observation data collected from China Bird Reports,which consists of 157272 observation records about 1145 bird species.Finally,we employed a kernel density estimator to identify geographical hotspots of bird habitat/stopover that are relevant to the influenza A(H7N9)infections.Results:Phylogenetic analysis reveals the evolutionary and geographical patterns of influenza A(H7N9)infections,where cases in the same or nearby municipality/provinces are clustered together with small evolutionary differences.Moreover,three epidemic waves in chicken along the East Asian-Australasian flyway in China are distinguished from the phylogenetic tree.The CCF analysis identifies possible migratory bird species that are relevant to the influenza A(H7N9)infections in Shanghai,Jiangsu,Zhejiang,Fujian,Jiangxi,and Guangdong in China,where the six municipality/provinces account for 91.2%of the total number of isolated H7N9 cases in chicken in GISAID.Based on the spatial distribution of identified bird species,geographical hotspots are further estimated and illustrated within these typical municipality/provinces.Conclusions:In this paper,we have identified key bird species and geographical hotspots that are relevant to the spread of influenza A(H7N9)virus.The results and findings could provide sentinel signal and evidence for active surveillance,as well as strategic control of influenza A(H7N9)transmission in China.
基金supported by the National Natural Science Foundation of China(No.31770573)。
文摘Migratory divides,where individuals from distinct breeding populations within a species exhibit divergent migratory routes and strategies,play a critical role in shaping avian ecology and evolution.These divides can drive intraspecific genetic divergence and promote reproductive isolation,potentially leading to population differentiation and speciation.Understanding the migration strategies of populations utilizing distinct flyways is essential not only for elucidating the mechanisms underlying migration patterns but also for informing effective species conservation efforts.From 2014 to 2023,we used satellite tracking to monitor the migration patterns of 87 White-naped Cranes(Antigone vipio)from the species'two breeding populations—western(Mongolia)and eastern(Songnen Plain,China).We delineated their migratory routes,quantified key migration parameters,and identified their population-and season-specific differences in migratory strategies.Our results indicate that the Greater Khingan Mountains and the Bohai-Yellow Sea formed a distinct migratory barrier separating the eastern and western populations.Significant differences in migration strategies were observed between populations and seasons.The western population adopts a"longer-distance,slower-speed,more-stopover"strategy,while the eastern population employs a"shorter-distance,higher-speed,fewer-stopover"strategy.Our study identifies the migratory divides between the two populations of White-naped Cranes and highlights the importance of migratory divides in shaping distinct migration strategies.These findings enhance our understanding of the factors driving population-specific migration strategies and provide a foundation for tailored conservation efforts for these populations.
文摘芝加哥是美国的一个重要城市,德莱塞的长篇小说Sister Carrie的背景城市,一百年之前早已喧嚣繁华。现在更是高楼林立。岂料,那里夜间灯火通明的高楼竟然成了无数候鸟的葬身之地！候鸟竟然和海里的鱼一样,具有趋光性。为此,芝加哥采取了高楼“减亮”等项措施,以拯救候鸟。本文文字信息丰富,优美通俗,值得细学。比如: We're not enduring the same energy crisis that's going on in California, butbuilding owners might be able to save a few pennies while performing a good deed。 本句信息:California(正遭受)energy crisis。 本句修辞:to save a few pennies(典型的understatement,低调) 本句句型:periodic sentence(圆周句)】
基金This study was supported by a grant from the National Natural Science Foundation of China （No. 81172735）.
文摘Background In March 2013,human cases of infection with a novel A （H7N9） influenza virus emerged in China.The epidemic spread quickly and as of 6 May 2013,there were 129 confirmed cases.The purpose of this study was to analyze the epidemiology of the confirmed cases,determine the impacts of bird migration and temperature changes on the H7N9 epidemic,predict the future trends of the epidemic,explore the response patterns of the government and propose preventive suggestions.Methods The geographic,temporal and population distribution of all cases reported up to 6 May 2013 were described from available records.Risk assessment standard was established by analysing the temperature and relative humidity records during the period of extensive outbreak in three epidemic regions in eastern China,including Shanghai,Zhejiang and Jiangsu provinces.Risk assessment maps were created by combining the bird migration routes in eastern China with the monthly average temperatures from May 1993 to December 2012 nationwide.Results Among the confirmed cases,there were more men than women,and 50.4％ were elderly adults （age ＞61 years）.The major demographic groups were retirees and farmers.The temperature on the days of disease onset was concentrated in the range of 9℃-19℃; we defined 9℃-19℃ as the high-risk temperature range,0℃-9℃ or 19℃-25℃ as medium risk and ＜0℃ or ＞25℃ as low risk.The relative humidity on the days of disease onset ranged widely from 25％ to 99％,but did not correlate with the incidence of infection.Based on the temperature analysis and the eastern bird migration routes,we predicted that after May,the high-risk region would move to the northeast and inland,while after September,it would move back to north China.Conclusions Temperature and bird migration strongly influence the spread of the H7N9 virus.In order to control the H7N9 epidemic effectively,Chinese authorities should strengthen the surveillance of migrating birds,increase poultry and environmental sampling,improve live poultry selling and husbandry patterns and move from a ＂passive response pattern＂to an ＂active response pattern＂ in focused preventive measures.
基金The work was supported by General Research Fund from Hong Kong Research Grants Council(PolyU 153277/16P)the Natural Sciences and Engineering Research Council of Canada(NSERC)(105588-2011)+1 种基金the Canadian Institutes of Health Research(CIHR)(289907)the Canada Research Chair Program(CRC)(230720).
文摘Lyme disease,a typical tick-borne disease,imposes increasing global public health challenges.A growing body of theoretical models have been proposed to better understand various factors determining the disease risk,which not only enrich our understanding on the ecological cycle of disease transmission but also promote new theoretical developments on model formulation,analysis and simulation.In this paper,we provide a review about the models and results we have obtained recently on modeling and analyzing Lyme disease transmission,with the purpose to highlight various aspects in the ecological cycle of disease transmission to be incorporated,including the growth of ticks with different stages in the life cycle,the seasonality,host diversity,spatial disease pattern due to host short distance movement and bird migration,co-infection with other tick-borne pathogens,and climate change impact.
