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Yumin Guo - One of the best experts on this subject based on the ideXlab platform.
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Satellite tracking reveals a new Migration Route of black-necked cranes (Grus nigricollis) in Qinghai-Tibet Plateau.
PeerJ, 2020Co-Authors: Ye Wang, Yumin GuoAbstract:The black-necked crane (Grus nigricollis) is a vulnerable species and the only species that lives in the plateau. Five Migration Routes of different populations have been identified, but for cranes wintering in Nyingchi Prefecture, Tibet, the Migration Route and breeding/summering area are still unknown. The aim of this study was to investigate the spatio-temporal Migration patterns of black-necked cranes in this area and to identify important areas for conservation. In 2016, we fitted seven black-necked cranes in Nyingchi with GPS-GSM satellite transmitters to record their Migration Routes. We used ArcGIS 10.2 to visualize important stopover sites and the 'ggplot' function in R to analyze the Migration patterns. From March 2016 to May 2019, we recorded nine spring Migration and four autumn Migration tracks from five individuals. Four individuals spent the breeding/summering season in Qinghai Lake, while the other spent the breeding/summering season in the Jinzihai Wetland of Dulan County, Qinghai Province. Detailed spatio-temporal information showed that the spring Migration lasted 8.7 ± 4.6 days and covered 1,182.5 ± 90.4 km, while the autumn Migration lasted 30 ± 10.6 days and covered 1,455.7 ± 138 km. Basom Lake and the Shazhuyu River were the most important stopover sites during the spring and autumn Migrations, respectively. The cranes spent 4.4 ± 3.7 days in Basom Lake and 26.3 ± 10.7 days in the Shazhuyu River. The black-necked cranes mainly migrated during the daytime (>85 % of the fly points), and 81 % (17/21) of all stopover and roosting sites were in the valley or at lakeside swamps. Only 17.7% (516 / 2,914) of the data points for stopover and roosting sites were in protected areas. Our study revealed the breeding/summering areas and Migration Routes of the black-necked cranes wintering in Nyingchi. These results contribute to a better understanding of the annual spatio-temporal Migration patterns and the development of conservation plans for this vulnerable species. ©2020 Wang et al.
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satellite tracking reveals a new Migration Route of black necked cranes grus nigricollis in qinghai tibet plateau
PeerJ, 2020Co-Authors: Ye Wang, Yumin GuoAbstract:Background The black-necked crane (Grus nigricollis) is a vulnerable species and the only species that lives in the plateau. Five Migration Routes of different populations have been identified, but for cranes wintering in Nyingchi Prefecture, Tibet, the Migration Route and breeding/summering area are still unknown. The aim of this study was to investigate the spatio-temporal Migration patterns of black-necked cranes in this area and to identify important areas for conservation. Methods In 2016, we fitted seven black-necked cranes in Nyingchi with GPS-GSM satellite transmitters to record their Migration Routes. We used ArcGIS 10.2 to visualize important stopover sites and the 'ggplot' function in R to analyze the Migration patterns. Results From March 2016 to May 2019, we recorded nine spring Migration and four autumn Migration tracks from five individuals. Four individuals spent the breeding/summering season in Qinghai Lake, while the other spent the breeding/summering season in the Jinzihai Wetland of Dulan County, Qinghai Province. Detailed spatio-temporal information showed that the spring Migration lasted 8.7 ± 4.6 days and covered 1,182.5 ± 90.4 km, while the autumn Migration lasted 30 ± 10.6 days and covered 1,455.7 ± 138 km. Basom Lake and the Shazhuyu River were the most important stopover sites during the spring and autumn Migrations, respectively. The cranes spent 4.4 ± 3.7 days in Basom Lake and 26.3 ± 10.7 days in the Shazhuyu River. The black-necked cranes mainly migrated during the daytime (>85 % of the fly points), and 81 % (17/21) of all stopover and roosting sites were in the valley or at lakeside swamps. Only 17.7% (516 / 2,914) of the data points for stopover and roosting sites were in protected areas. Main conclusions Our study revealed the breeding/summering areas and Migration Routes of the black-necked cranes wintering in Nyingchi. These results contribute to a better understanding of the annual spatio-temporal Migration patterns and the development of conservation plans for this vulnerable species.
Lukas Jenni - One of the best experts on this subject based on the ideXlab platform.
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Stopover durations of three warbler species along their autumn Migration Route.
Oecologia, 2001Co-Authors: Michael Schaub, Lukas JenniAbstract:In migrating birds, the success of Migration is determined by stopover duration, the most important factor determining overall speed of Migration, and fuel deposition rate. However, very little is known about stopover durations of small migrant birds, because appropriate methods for data analysis were lacking until recently. We used a new capture-recapture analysis to estimate stopover durations of 1st-year reed warblers Acrocephalus scirpaceus, sedge warblers A. schoenobaenus and garden warblers Sylvia borin at 17 stopover sites in Europe and Africa during autumn. Average stopover duration of non-moulting reed warblers was 9.5 days while moulting conspecifics stayed about twice as long. Average stopover duration of sedge warblers was 9.1 days and, in contrast to the other two species, differed between years at several sites. Garden warblers stayed 7.7 days on average. The long stopover duration of the reed warbler, resulting in slow overall Migration speed, is related to its low fuel deposition rate. It can be explained by low, but predictable, food resources and an early departure during moult. Compared to the reed warbler, the stopover duration of the sedge warbler varies more between sites and probably also between years, as the supply of its preferred diet (reed aphids) is spatially and temporally unpredictable but can be superabundant. The short stopover duration of the garden warbler, leading to high overall Migration speed, can be related to high fuel deposition rates, probably brought about by a change to an abundant, predictable and long-lasting fruit diet. Within species, stopover duration did not change significantly along the Migration Route. Hence, an increase of Migration speed along the Migration Route, as suggested in the literature, may be caused by longer flight bouts in the south. However, it remains largely unknown which environmental and possibly endogenous factors regulate stopover duration.
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body mass of six long distance migrant passerine species along the autumn Migration Route
Journal of Ornithology, 2000Co-Authors: Michael Schaub, Lukas JenniAbstract:We analysed body mass and moult data of six passerine species along their autumn Migration Route from northern Europe to North Africa and derived hypothetical models of the organisation of their Migration in terms of fuel store accumulation. We analysed data of 46,541 first-year birds from 34 trapping sites, sampled in a network of collaborating European and African ringing stations. After accounting for effects of time of day and size, there were marked differences between the six species examined in the change of body mass along the Migration Route and in the timing of moult. Garden Warblers (Sylvia borin) and Pied Flycatchers (Ficedula hypoleuca) underwent their postjuvenile moult prior to Migration and increased their average body mass along the Migration Route. Sedge Warblers (Acrocephalus schoenobaenus) also increased body mass towards the south, but started the Migration bout without further refuelling well before the Sahara and moulted mainly in the wintering grounds. Reed Warblers (Acrocephalus scirpaceus) and Whitethroats (Sylvia communis) migrated while still moulting and did not increase average body mass towards south. They accumulated the energy needed to fly over the Sahara just before it. Spotted Flycatchers (Muscicapa striata) behaved in the same way, but contrary to Reed Warblers and Whitethroats they did not accumulate much fat stores in North Africa, which might urge them to stop and fuel up regularly in the Sahara. In the course of the season average body mass of all species increased slightly, which enabled them to migrate faster. In general, average body mass of first-year birds in northern and central Europe during the Migration period was comparable to that of adults during breeding.
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Fuel deposition of three passerine bird species along the Migration Route.
Oecologia, 2000Co-Authors: Michael Schaub, Lukas JenniAbstract:The rate at which migrant birds replenish their energy stores at intermittent stopovers largely determines overall Migration speed, the manner in which Migration proceeds and success of Migration. In this study, data on the fuel deposition rate (FDR) of three long-distance migrants from 17 ringing sites along their autumn Migration Route were used to examine: (1) effects of endogenous factors on FDR, and (2) how relationships between exogenous factors and FDR affect the organisation of Migration. We developed a model to estimate FDR from retrapped birds which takes into account time of day and various other factors which might influence FDR. The two endogenous factors, moult and current energy stores, generally reduced FDR. This may result in lower departure energy loads and more stopovers than expected from optimal Migration theory. Differences between species with respect to seasonal, year-to-year and geographical patterns of FDR could be related to differences in availability and predictability of food resources, and help to explain differences in the organisation of Migration. A low FDR in northern and central Europe could be related to low, but predictable, food resources and an early departure during moult of the reed warbler (Acrocephalus scirpaceus); FDRs varying between years were related to large spatial and year-to-year variation in the density of the main prey of the sedge warbler (Acrocephalus schoenobaenus); and a high FDR in the garden warbler (Sylvia borin) was related to abundant food resources, due to a switch from a purely invertebrate diet to a mixed diet including fruits which are abundant over large areas of Europe and north Africa. This study demonstrated that the organisation of Migration is the outcome of a complex interplay of the seasonal timing of moult, food availability and predictability and a seasonal switch in diet, and can be modified by individual birds in response to a limited amount of time in which to migrate.
Franz Bairlein - One of the best experts on this subject based on the ideXlab platform.
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Flexible reaction norms to environmental variables along the Migration Route and the significance of stopover duration for total speed of Migration in a songbird migrant.
Frontiers in zoology, 2017Co-Authors: Heiko Schmaljohann, Simeon Lisovski, Franz BairleinAbstract:Predicting the consequences of continuing anthropogenic changes in the environment for migratory behaviours such as phenology remains a major challenge. Predictions remain particularly difficult, because our knowledge is based on studies from single-snapshot observations at specific stopover sites along birds’ Migration Routes. However, a general understanding on how birds react to prevailing environmental conditions, e.g. their ‘phenotypic reaction norm’, throughout the annual cycle and along their entire Migration Routes is required to fully understand how migratory birds respond to rapid environmental change. Here, we provide direct evidence that northern wheatears (Oenanthe oenanthe) from a breeding population in Alaska adjusted their probability to resume Migration as well as the distance covered per night, i.e. travel speed, to large-scale environmental conditions experienced along their 15,000 km migratory Route on both northwards and southwards Migrations. These adjustments were found to be flexible in space and time. At the beginning of autumn Migration, northern wheatears showed high departure probabilities and high travel speeds at low surface air temperatures, while far away from Alaska both traits decreased with increasing air temperatures. In spring, northern wheatears increasingly exploited flow assistance with season, which is likely a behavioural adjustment to speed up Migration by increasing the distance travelled per night. Furthermore, the variation in total stopover duration but not in travel speed had a significant effect on the total speed of Migration, indicating the prime importance of total stopover duration in the overall phenology of bird Migration. Northern wheatears from Alaska provide evidence that the phenotypic reaction norm to a set of environmental conditions cannot be generalized to universal and persistent behavioural reaction pattern across entire migratory pathways. This highlights the importance of full annual-cycle studies on migratory birds to better understand their response to the environment. Understanding the mechanisms behind phenotypic plasticity during Migration is particularly important in the assessment of whether birds can keep pace with the potentially increasing phenological mismatches observed on the breeding grounds.
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The nature of the Migration Route shapes physiological traits and aerodynamic properties in a migratory songbird
Behavioral Ecology and Sociobiology, 2014Co-Authors: Anna-marie Corman, Franz Bairlein, Heiko SchmaljohannAbstract:Migration distance is supposed to represent an important selection pressure shaping physiological and morphological properties. Previous work has focussed on this effect, while the importance of ecological barriers in this context has been rarely considered. We studied two subspecies of a migratory songbird, the northern wheatear ( Oenanthe oenanthe oenanthe and O. o. leucorhoa L.), on an island in the North Sea. The former subspecies reaches their Scandinavian breeding areas after a short sea crossing, whereas leucorhoa northern wheatears cross the North Atlantic towards Iceland, Greenland or Canada. Physiological traits (fuel deposition rate) and wings’ aerodynamic properties (wing pointedness independent of body size), both affecting Migration speed, were hypothesized to be more pronounced in leucorhoa than in oenanthe northern wheatears. Within subspecies, the physiological and aerodynamic properties were hypothesized to explain arrival date at the stopover site with “fast migrants” arriving early. Physiological and aerodynamic properties in leucorhoa northern wheatears lead to a faster and less costly Migration, favouring a sea crossing, but in trade-off lower flight manoeuvrability than in oenanthe birds. Wings’ aerodynamic properties affected the seasonal occurrence of leucorhoa females, whereas the physiological traits significantly influenced arrival date in oenanthe individuals. The less risky Migration Route in oenanthe birds with few short sea crossings may have favoured higher flight manoeuvrability for foraging (less pointed wings), in trade-off an energetically more costly flight. Hence, not the Migration distance itself, but the presence/absence of a sea barrier presents an important selection pressure in migratory land birds favouring low flight costs.
Heiko Schmaljohann - One of the best experts on this subject based on the ideXlab platform.
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Flexible reaction norms to environmental variables along the Migration Route and the significance of stopover duration for total speed of Migration in a songbird migrant.
Frontiers in zoology, 2017Co-Authors: Heiko Schmaljohann, Simeon Lisovski, Franz BairleinAbstract:Predicting the consequences of continuing anthropogenic changes in the environment for migratory behaviours such as phenology remains a major challenge. Predictions remain particularly difficult, because our knowledge is based on studies from single-snapshot observations at specific stopover sites along birds’ Migration Routes. However, a general understanding on how birds react to prevailing environmental conditions, e.g. their ‘phenotypic reaction norm’, throughout the annual cycle and along their entire Migration Routes is required to fully understand how migratory birds respond to rapid environmental change. Here, we provide direct evidence that northern wheatears (Oenanthe oenanthe) from a breeding population in Alaska adjusted their probability to resume Migration as well as the distance covered per night, i.e. travel speed, to large-scale environmental conditions experienced along their 15,000 km migratory Route on both northwards and southwards Migrations. These adjustments were found to be flexible in space and time. At the beginning of autumn Migration, northern wheatears showed high departure probabilities and high travel speeds at low surface air temperatures, while far away from Alaska both traits decreased with increasing air temperatures. In spring, northern wheatears increasingly exploited flow assistance with season, which is likely a behavioural adjustment to speed up Migration by increasing the distance travelled per night. Furthermore, the variation in total stopover duration but not in travel speed had a significant effect on the total speed of Migration, indicating the prime importance of total stopover duration in the overall phenology of bird Migration. Northern wheatears from Alaska provide evidence that the phenotypic reaction norm to a set of environmental conditions cannot be generalized to universal and persistent behavioural reaction pattern across entire migratory pathways. This highlights the importance of full annual-cycle studies on migratory birds to better understand their response to the environment. Understanding the mechanisms behind phenotypic plasticity during Migration is particularly important in the assessment of whether birds can keep pace with the potentially increasing phenological mismatches observed on the breeding grounds.
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The nature of the Migration Route shapes physiological traits and aerodynamic properties in a migratory songbird
Behavioral Ecology and Sociobiology, 2014Co-Authors: Anna-marie Corman, Franz Bairlein, Heiko SchmaljohannAbstract:Migration distance is supposed to represent an important selection pressure shaping physiological and morphological properties. Previous work has focussed on this effect, while the importance of ecological barriers in this context has been rarely considered. We studied two subspecies of a migratory songbird, the northern wheatear ( Oenanthe oenanthe oenanthe and O. o. leucorhoa L.), on an island in the North Sea. The former subspecies reaches their Scandinavian breeding areas after a short sea crossing, whereas leucorhoa northern wheatears cross the North Atlantic towards Iceland, Greenland or Canada. Physiological traits (fuel deposition rate) and wings’ aerodynamic properties (wing pointedness independent of body size), both affecting Migration speed, were hypothesized to be more pronounced in leucorhoa than in oenanthe northern wheatears. Within subspecies, the physiological and aerodynamic properties were hypothesized to explain arrival date at the stopover site with “fast migrants” arriving early. Physiological and aerodynamic properties in leucorhoa northern wheatears lead to a faster and less costly Migration, favouring a sea crossing, but in trade-off lower flight manoeuvrability than in oenanthe birds. Wings’ aerodynamic properties affected the seasonal occurrence of leucorhoa females, whereas the physiological traits significantly influenced arrival date in oenanthe individuals. The less risky Migration Route in oenanthe birds with few short sea crossings may have favoured higher flight manoeuvrability for foraging (less pointed wings), in trade-off an energetically more costly flight. Hence, not the Migration distance itself, but the presence/absence of a sea barrier presents an important selection pressure in migratory land birds favouring low flight costs.
Ye Wang - One of the best experts on this subject based on the ideXlab platform.
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Satellite tracking reveals a new Migration Route of black-necked cranes (Grus nigricollis) in Qinghai-Tibet Plateau.
PeerJ, 2020Co-Authors: Ye Wang, Yumin GuoAbstract:The black-necked crane (Grus nigricollis) is a vulnerable species and the only species that lives in the plateau. Five Migration Routes of different populations have been identified, but for cranes wintering in Nyingchi Prefecture, Tibet, the Migration Route and breeding/summering area are still unknown. The aim of this study was to investigate the spatio-temporal Migration patterns of black-necked cranes in this area and to identify important areas for conservation. In 2016, we fitted seven black-necked cranes in Nyingchi with GPS-GSM satellite transmitters to record their Migration Routes. We used ArcGIS 10.2 to visualize important stopover sites and the 'ggplot' function in R to analyze the Migration patterns. From March 2016 to May 2019, we recorded nine spring Migration and four autumn Migration tracks from five individuals. Four individuals spent the breeding/summering season in Qinghai Lake, while the other spent the breeding/summering season in the Jinzihai Wetland of Dulan County, Qinghai Province. Detailed spatio-temporal information showed that the spring Migration lasted 8.7 ± 4.6 days and covered 1,182.5 ± 90.4 km, while the autumn Migration lasted 30 ± 10.6 days and covered 1,455.7 ± 138 km. Basom Lake and the Shazhuyu River were the most important stopover sites during the spring and autumn Migrations, respectively. The cranes spent 4.4 ± 3.7 days in Basom Lake and 26.3 ± 10.7 days in the Shazhuyu River. The black-necked cranes mainly migrated during the daytime (>85 % of the fly points), and 81 % (17/21) of all stopover and roosting sites were in the valley or at lakeside swamps. Only 17.7% (516 / 2,914) of the data points for stopover and roosting sites were in protected areas. Our study revealed the breeding/summering areas and Migration Routes of the black-necked cranes wintering in Nyingchi. These results contribute to a better understanding of the annual spatio-temporal Migration patterns and the development of conservation plans for this vulnerable species. ©2020 Wang et al.
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satellite tracking reveals a new Migration Route of black necked cranes grus nigricollis in qinghai tibet plateau
PeerJ, 2020Co-Authors: Ye Wang, Yumin GuoAbstract:Background The black-necked crane (Grus nigricollis) is a vulnerable species and the only species that lives in the plateau. Five Migration Routes of different populations have been identified, but for cranes wintering in Nyingchi Prefecture, Tibet, the Migration Route and breeding/summering area are still unknown. The aim of this study was to investigate the spatio-temporal Migration patterns of black-necked cranes in this area and to identify important areas for conservation. Methods In 2016, we fitted seven black-necked cranes in Nyingchi with GPS-GSM satellite transmitters to record their Migration Routes. We used ArcGIS 10.2 to visualize important stopover sites and the 'ggplot' function in R to analyze the Migration patterns. Results From March 2016 to May 2019, we recorded nine spring Migration and four autumn Migration tracks from five individuals. Four individuals spent the breeding/summering season in Qinghai Lake, while the other spent the breeding/summering season in the Jinzihai Wetland of Dulan County, Qinghai Province. Detailed spatio-temporal information showed that the spring Migration lasted 8.7 ± 4.6 days and covered 1,182.5 ± 90.4 km, while the autumn Migration lasted 30 ± 10.6 days and covered 1,455.7 ± 138 km. Basom Lake and the Shazhuyu River were the most important stopover sites during the spring and autumn Migrations, respectively. The cranes spent 4.4 ± 3.7 days in Basom Lake and 26.3 ± 10.7 days in the Shazhuyu River. The black-necked cranes mainly migrated during the daytime (>85 % of the fly points), and 81 % (17/21) of all stopover and roosting sites were in the valley or at lakeside swamps. Only 17.7% (516 / 2,914) of the data points for stopover and roosting sites were in protected areas. Main conclusions Our study revealed the breeding/summering areas and Migration Routes of the black-necked cranes wintering in Nyingchi. These results contribute to a better understanding of the annual spatio-temporal Migration patterns and the development of conservation plans for this vulnerable species.