The Experts below are selected from a list of 14676 Experts worldwide ranked by ideXlab platform
Aivar Leito - One of the best experts on this subject based on the ideXlab platform.
-
Shallow genetic population structure in an expanding migratory bird with high breeding site fidelity, the Western Eurasian Crane Grus Grus Grus
Journal of Ornithology, 2019Co-Authors: Martin Haase, Henriette Höltje, Beate Blahy, Damon Bridge, Eberhard Henne, Ulf S. Johansson, Katrin Kaldma, Ekaterina A. Khudyakova, Amy King, Aivar LeitoAbstract:Geringe genetische Populationsstruktur eines sich ausbreitenden Zugvogels mit hoher Brutortreue, des Westlichen Eurasischen Kranichs, Grus Grus Grus Seit mehr als einem halben Jahrhundert breitet sich der Eurasische Kranich ( Grus Grus Grus ) wieder nach Westeuropa bis hin nach Großbritannien, den Niederlanden und Dänemark aus, wo er ausgerottet war. Der Eurasische Kranich ist einerseits eine sehr mobile, ziehende Art. Andererseits ist er territorial und zeichnet sich durch eine hohe Brutplatztreue aus. Die genetische Populationsstruktur ist somit von gegensätzlichen Kräften mit unterschiedlichen Konsequenzen geprägt. Wir ermittelten die Populationsstruktur der Westeuropäischen Population (WEP) des Eurasischen Kranichs basierend auf sechs hochvariablen Mikrosatelliten-Loci und Samples aus acht Regionen. Wir kombinierten klassische F-Statistik einschließlich molekularer Varianzanzanalysen mit a priori festgelegter Struktur mit divisiven Clusteranalysen—einer Bayes’schen Methode (STRUCTURE) und einer Diskriminanzanalyse von Hauptkomponenten (DAPC)–, die die Struktur a posteriori schätzen. Die F-Statistik zeigte, dass die Populationen nur gering differenziert waren. Der Großteil der genetischen Varianz (> 90%) lag auf Ebene der Individuen. Auf den ersten Blick schienen die divisiven Ansätze ein übereinstimmendes Bild zu zeichnen. Beide fanden vier Cluster. Allerdings gab es keinerlei Übereinstimmung in der Zusammensetzung der Cluster und keines der Resultate war biologisch sinnvoll. STRUCTURE wies allerdings die höchste Wahrscheinlichkeit einem Szenario ohne Populationsunterteilung zu und lieferte somit eine alternative Interpretation, die mit der F-Statistik übereinstimmte. Daher schließen wir, dass die WEP des Eurasischen Kranichs weitestgehend homogen ist. For more than half a century, the Western Eurasian Crane ( Grus Grus Grus ) has been expanding its range toward western Europe, recolonizing areas where it had been previously driven to extinction, including the UK, the Netherlands and Denmark. The Western Eurasian Crane is, on the one hand, a very mobile, migratory species, but on the other, is territorial and shows high breeding site fidelity. Hence, its genetic population structure is subject to antagonizing forces, which have different consequences. Based on the genotyping of six highly variable microsatellite loci, we inferred the population structure of the Western Eurasian Crane from samples from eight regions. We integrated classic F -statistics including analyses of molecular variance with a priori designation of structure and divisive clustering approaches, i.e. a Bayesian procedure (STRUCTURE) and discriminant analysis of principal components, which infer structure a posteriori. According to the F -statistics, populations were only weakly differentiated, and the majority of the genetic variance (> 90%) was attributed to individuals. At first glance, the divisive approaches appeared to agree in finding four clusters. Yet, there was no correspondence regarding the composition of the clusters and none of the results were biologically meaningful. However, STRUCTURE delivered an alternative interpretation, designating the highest likelihood to a scenario without subdivision, in clear agreement with the findings based on the F -statistics. In conclusion, the Western Eurasian Crane is genetically largely homogeneous, probably as a consequence of the rapid growth and range expansion of its population.
-
Shallow genetic population structure in an expanding migratory bird with high breeding site fidelity, the Western Eurasian Crane Grus Grus Grus
Journal of Ornithology, 2019Co-Authors: Martin Haase, Henriette Höltje, Beate Blahy, Damon Bridge, Eberhard Henne, Ulf S. Johansson, Katrin Kaldma, Ekaterina A. Khudyakova, Amy King, Aivar LeitoAbstract:Geringe genetische Populationsstruktur eines sich ausbreitenden Zugvogels mit hoher Brutortreue, des Westlichen Eurasischen Kranichs, Grus Grus Grus Seit mehr als einem halben Jahrhundert breitet sich der Eurasische Kranich ( Grus Grus Grus ) wieder nach Westeuropa bis hin nach Großbritannien, den Niederlanden und Dänemark aus, wo er ausgerottet war. Der Eurasische Kranich ist einerseits eine sehr mobile, ziehende Art. Andererseits ist er territorial und zeichnet sich durch eine hohe Brutplatztreue aus. Die genetische Populationsstruktur ist somit von gegensätzlichen Kräften mit unterschiedlichen Konsequenzen geprägt. Wir ermittelten die Populationsstruktur der Westeuropäischen Population (WEP) des Eurasischen Kranichs basierend auf sechs hochvariablen Mikrosatelliten-Loci und Samples aus acht Regionen. Wir kombinierten klassische F-Statistik einschließlich molekularer Varianzanzanalysen mit a priori festgelegter Struktur mit divisiven Clusteranalysen—einer Bayes’schen Methode (STRUCTURE) und einer Diskriminanzanalyse von Hauptkomponenten (DAPC)–, die die Struktur a posteriori schätzen. Die F-Statistik zeigte, dass die Populationen nur gering differenziert waren. Der Großteil der genetischen Varianz (> 90%) lag auf Ebene der Individuen. Auf den ersten Blick schienen die divisiven Ansätze ein übereinstimmendes Bild zu zeichnen. Beide fanden vier Cluster. Allerdings gab es keinerlei Übereinstimmung in der Zusammensetzung der Cluster und keines der Resultate war biologisch sinnvoll. STRUCTURE wies allerdings die höchste Wahrscheinlichkeit einem Szenario ohne Populationsunterteilung zu und lieferte somit eine alternative Interpretation, die mit der F-Statistik übereinstimmte. Daher schließen wir, dass die WEP des Eurasischen Kranichs weitestgehend homogen ist. For more than half a century, the Western Eurasian Crane ( Grus Grus Grus ) has been expanding its range toward western Europe, recolonizing areas where it had been previously driven to extinction, including the UK, the Netherlands and Denmark. The Western Eurasian Crane is, on the one hand, a very mobile, migratory species, but on the other, is territorial and shows high breeding site fidelity. Hence, its genetic population structure is subject to antagonizing forces, which have different consequences. Based on the genotyping of six highly variable microsatellite loci, we inferred the population structure of the Western Eurasian Crane from samples from eight regions. We integrated classic F -statistics including analyses of molecular variance with a priori designation of structure and divisive clustering approaches, i.e. a Bayesian procedure (STRUCTURE) and discriminant analysis of principal components, which infer structure a posteriori. According to the F -statistics, populations were only weakly differentiated, and the majority of the genetic variance (> 90%) was attributed to individuals. At first glance, the divisive approaches appeared to agree in finding four clusters. Yet, there was no correspondence regarding the composition of the clusters and none of the results were biologically meaningful. However, STRUCTURE delivered an alternative interpretation, designating the highest likelihood to a scenario without subdivision, in clear agreement with the findings based on the F -statistics. In conclusion, the Western Eurasian Crane is genetically largely homogeneous, probably as a consequence of the rapid growth and range expansion of its population.
-
Shallow genetic population structure in an expanding migratory bird with high breeding site fidelity, the Western Eurasian Crane Grus Grus Grus
Journal of Ornithology, 2019Co-Authors: Martin Haase, Henriette Höltje, Beate Blahy, Damon Bridge, Eberhard Henne, Ulf S. Johansson, Katrin Kaldma, Ekaterina A. Khudyakova, Amy King, Aivar LeitoAbstract:For more than half a century, the Western Eurasian Crane (Grus Grus Grus) has been expanding its range toward western Europe, recolonizing areas where it had been previously driven to extinction, including the UK, the Netherlands and Denmark. The Western Eurasian Crane is, on the one hand, a very mobile, migratory species, but on the other, is territorial and shows high breeding site fidelity. Hence, its genetic population structure is subject to antagonizing forces, which have different consequences. Based on the genotyping of six highly variable microsatellite loci, we inferred the population structure of the Western Eurasian Crane from samples from eight regions. We integrated classic F-statistics including analyses of molecular variance with a priori designation of structure and divisive clustering approaches, i.e. a Bayesian procedure (STRUCTURE) and discriminant analysis of principal components, which infer structure a posteriori. According to the F-statistics, populations were only weakly differentiated, and the majority of the genetic variance (> 90%) was attributed to individuals. At first glance, the divisive approaches appeared to agree in finding four clusters. Yet, there was no correspondence regarding the composition of the clusters and none of the results were biologically meaningful. However, STRUCTURE delivered an alternative interpretation, designating the highest likelihood to a scenario without subdivision, in clear agreement with the findings based on the F-statistics. In conclusion, the Western Eurasian Crane is genetically largely homogeneous, probably as a consequence of the rapid growth and range expansion of its population.
-
The potential impacts of changes in ecological networks, land use and climate on the Eurasian crane population in Estonia
Landscape Ecology, 2015Co-Authors: Aivar Leito, Robert G.h. Bunce, Mart Külvik, Ivar Ojaste, Janar Raet, Miguel Villoslada, Meelis Leivits, Anne Kull, Valdo Kuusemets, Tiiu KullAbstract:Context The Eurasian crane (Grus Grus) is an iconic and sensitive species. It is therefore necessary to understand its landscape ecology in order to determine threats.
-
The impact of agriculture on autumn staging Eurasian Cranes (Grus Grus) in Estonia
Agricultural and Food Science, 2008Co-Authors: Aivar Leito, J. Truu, M. ÕunsaarAbstract:This paper explores the relation between the local numbers and distribution of autumn staging Eurasian Cranes (Grus Grus Linn.) and agricultural land use during recent decades in Estonia. The analysis is based on the long-term monitoring data of staging cranes and the statistical data of land use in Estonia. We found that great changes in cropping area, as well as in crane numbers have taken place in Estonia since the 1960s. We also found a significant positive correlation between crane numbers and the cropping area of summer wheat, winter wheat, winter rye and all cereals together, and a negative correlation with the area of potatoes. Generally, arable land, particularly that used for growing cereals, has a great influence on the local numbers and distribution of staging cranes. Based on our findings, we predict that changes in the local numbers and distribution of Eurasian Cranes staging during their migration in Estonia and elsewhere will depend on changes in agricultural land use in staging areas, rather than on the size of the breeding population. As about 10 percent of the European Eurasian Crane population stop over in Estonia during the autumn migration, the country has an important role to play in the protection of the species.
Martin Haase - One of the best experts on this subject based on the ideXlab platform.
-
Shallow genetic population structure in an expanding migratory bird with high breeding site fidelity, the Western Eurasian Crane Grus Grus Grus
Journal of Ornithology, 2019Co-Authors: Martin Haase, Henriette Höltje, Beate Blahy, Damon Bridge, Eberhard Henne, Ulf S. Johansson, Katrin Kaldma, Ekaterina A. Khudyakova, Amy King, Aivar LeitoAbstract:Geringe genetische Populationsstruktur eines sich ausbreitenden Zugvogels mit hoher Brutortreue, des Westlichen Eurasischen Kranichs, Grus Grus Grus Seit mehr als einem halben Jahrhundert breitet sich der Eurasische Kranich ( Grus Grus Grus ) wieder nach Westeuropa bis hin nach Großbritannien, den Niederlanden und Dänemark aus, wo er ausgerottet war. Der Eurasische Kranich ist einerseits eine sehr mobile, ziehende Art. Andererseits ist er territorial und zeichnet sich durch eine hohe Brutplatztreue aus. Die genetische Populationsstruktur ist somit von gegensätzlichen Kräften mit unterschiedlichen Konsequenzen geprägt. Wir ermittelten die Populationsstruktur der Westeuropäischen Population (WEP) des Eurasischen Kranichs basierend auf sechs hochvariablen Mikrosatelliten-Loci und Samples aus acht Regionen. Wir kombinierten klassische F-Statistik einschließlich molekularer Varianzanzanalysen mit a priori festgelegter Struktur mit divisiven Clusteranalysen—einer Bayes’schen Methode (STRUCTURE) und einer Diskriminanzanalyse von Hauptkomponenten (DAPC)–, die die Struktur a posteriori schätzen. Die F-Statistik zeigte, dass die Populationen nur gering differenziert waren. Der Großteil der genetischen Varianz (> 90%) lag auf Ebene der Individuen. Auf den ersten Blick schienen die divisiven Ansätze ein übereinstimmendes Bild zu zeichnen. Beide fanden vier Cluster. Allerdings gab es keinerlei Übereinstimmung in der Zusammensetzung der Cluster und keines der Resultate war biologisch sinnvoll. STRUCTURE wies allerdings die höchste Wahrscheinlichkeit einem Szenario ohne Populationsunterteilung zu und lieferte somit eine alternative Interpretation, die mit der F-Statistik übereinstimmte. Daher schließen wir, dass die WEP des Eurasischen Kranichs weitestgehend homogen ist. For more than half a century, the Western Eurasian Crane ( Grus Grus Grus ) has been expanding its range toward western Europe, recolonizing areas where it had been previously driven to extinction, including the UK, the Netherlands and Denmark. The Western Eurasian Crane is, on the one hand, a very mobile, migratory species, but on the other, is territorial and shows high breeding site fidelity. Hence, its genetic population structure is subject to antagonizing forces, which have different consequences. Based on the genotyping of six highly variable microsatellite loci, we inferred the population structure of the Western Eurasian Crane from samples from eight regions. We integrated classic F -statistics including analyses of molecular variance with a priori designation of structure and divisive clustering approaches, i.e. a Bayesian procedure (STRUCTURE) and discriminant analysis of principal components, which infer structure a posteriori. According to the F -statistics, populations were only weakly differentiated, and the majority of the genetic variance (> 90%) was attributed to individuals. At first glance, the divisive approaches appeared to agree in finding four clusters. Yet, there was no correspondence regarding the composition of the clusters and none of the results were biologically meaningful. However, STRUCTURE delivered an alternative interpretation, designating the highest likelihood to a scenario without subdivision, in clear agreement with the findings based on the F -statistics. In conclusion, the Western Eurasian Crane is genetically largely homogeneous, probably as a consequence of the rapid growth and range expansion of its population.
-
Shallow genetic population structure in an expanding migratory bird with high breeding site fidelity, the Western Eurasian Crane Grus Grus Grus
Journal of Ornithology, 2019Co-Authors: Martin Haase, Henriette Höltje, Beate Blahy, Damon Bridge, Eberhard Henne, Ulf S. Johansson, Katrin Kaldma, Ekaterina A. Khudyakova, Amy King, Aivar LeitoAbstract:Geringe genetische Populationsstruktur eines sich ausbreitenden Zugvogels mit hoher Brutortreue, des Westlichen Eurasischen Kranichs, Grus Grus Grus Seit mehr als einem halben Jahrhundert breitet sich der Eurasische Kranich ( Grus Grus Grus ) wieder nach Westeuropa bis hin nach Großbritannien, den Niederlanden und Dänemark aus, wo er ausgerottet war. Der Eurasische Kranich ist einerseits eine sehr mobile, ziehende Art. Andererseits ist er territorial und zeichnet sich durch eine hohe Brutplatztreue aus. Die genetische Populationsstruktur ist somit von gegensätzlichen Kräften mit unterschiedlichen Konsequenzen geprägt. Wir ermittelten die Populationsstruktur der Westeuropäischen Population (WEP) des Eurasischen Kranichs basierend auf sechs hochvariablen Mikrosatelliten-Loci und Samples aus acht Regionen. Wir kombinierten klassische F-Statistik einschließlich molekularer Varianzanzanalysen mit a priori festgelegter Struktur mit divisiven Clusteranalysen—einer Bayes’schen Methode (STRUCTURE) und einer Diskriminanzanalyse von Hauptkomponenten (DAPC)–, die die Struktur a posteriori schätzen. Die F-Statistik zeigte, dass die Populationen nur gering differenziert waren. Der Großteil der genetischen Varianz (> 90%) lag auf Ebene der Individuen. Auf den ersten Blick schienen die divisiven Ansätze ein übereinstimmendes Bild zu zeichnen. Beide fanden vier Cluster. Allerdings gab es keinerlei Übereinstimmung in der Zusammensetzung der Cluster und keines der Resultate war biologisch sinnvoll. STRUCTURE wies allerdings die höchste Wahrscheinlichkeit einem Szenario ohne Populationsunterteilung zu und lieferte somit eine alternative Interpretation, die mit der F-Statistik übereinstimmte. Daher schließen wir, dass die WEP des Eurasischen Kranichs weitestgehend homogen ist. For more than half a century, the Western Eurasian Crane ( Grus Grus Grus ) has been expanding its range toward western Europe, recolonizing areas where it had been previously driven to extinction, including the UK, the Netherlands and Denmark. The Western Eurasian Crane is, on the one hand, a very mobile, migratory species, but on the other, is territorial and shows high breeding site fidelity. Hence, its genetic population structure is subject to antagonizing forces, which have different consequences. Based on the genotyping of six highly variable microsatellite loci, we inferred the population structure of the Western Eurasian Crane from samples from eight regions. We integrated classic F -statistics including analyses of molecular variance with a priori designation of structure and divisive clustering approaches, i.e. a Bayesian procedure (STRUCTURE) and discriminant analysis of principal components, which infer structure a posteriori. According to the F -statistics, populations were only weakly differentiated, and the majority of the genetic variance (> 90%) was attributed to individuals. At first glance, the divisive approaches appeared to agree in finding four clusters. Yet, there was no correspondence regarding the composition of the clusters and none of the results were biologically meaningful. However, STRUCTURE delivered an alternative interpretation, designating the highest likelihood to a scenario without subdivision, in clear agreement with the findings based on the F -statistics. In conclusion, the Western Eurasian Crane is genetically largely homogeneous, probably as a consequence of the rapid growth and range expansion of its population.
-
Shallow genetic population structure in an expanding migratory bird with high breeding site fidelity, the Western Eurasian Crane Grus Grus Grus
Journal of Ornithology, 2019Co-Authors: Martin Haase, Henriette Höltje, Beate Blahy, Damon Bridge, Eberhard Henne, Ulf S. Johansson, Katrin Kaldma, Ekaterina A. Khudyakova, Amy King, Aivar LeitoAbstract:For more than half a century, the Western Eurasian Crane (Grus Grus Grus) has been expanding its range toward western Europe, recolonizing areas where it had been previously driven to extinction, including the UK, the Netherlands and Denmark. The Western Eurasian Crane is, on the one hand, a very mobile, migratory species, but on the other, is territorial and shows high breeding site fidelity. Hence, its genetic population structure is subject to antagonizing forces, which have different consequences. Based on the genotyping of six highly variable microsatellite loci, we inferred the population structure of the Western Eurasian Crane from samples from eight regions. We integrated classic F-statistics including analyses of molecular variance with a priori designation of structure and divisive clustering approaches, i.e. a Bayesian procedure (STRUCTURE) and discriminant analysis of principal components, which infer structure a posteriori. According to the F-statistics, populations were only weakly differentiated, and the majority of the genetic variance (> 90%) was attributed to individuals. At first glance, the divisive approaches appeared to agree in finding four clusters. Yet, there was no correspondence regarding the composition of the clusters and none of the results were biologically meaningful. However, STRUCTURE delivered an alternative interpretation, designating the highest likelihood to a scenario without subdivision, in clear agreement with the findings based on the F-statistics. In conclusion, the Western Eurasian Crane is genetically largely homogeneous, probably as a consequence of the rapid growth and range expansion of its population.
-
Genetic evidence of female specific eggshell colouration in the Common Crane (Grus Grus)
Journal of Ornithology, 2016Co-Authors: Henriette Höltje, Martin Haase, Wolfgang Mewes, Angela Schmitz OrnésAbstract:The large variation in colouration and patterning of bird eggs suggests a variety of functions. For instance, in cases of intra- and inter-specific brood parasitism, the recognition of own eggs by the parents could be essential for their reproductive success. However, individual specific signatures may also be of interest from an applied point of view, as it would be possible to monitor individual females across breeding seasons by identifying their eggs. This would be of particular importance for species that are difficult to catch and ring such as the Common Crane ( Grus Grus ). Since 2004, nest monitoring of this species has been conducted by one of us (W.M.) in north-east Germany, which led to the development of a semi-quantitative method to identify female cranes by diagnostic egg features including ground colour and spots of eggshells. In order to verify this approach, we quantitatively determined the spot patterns on eggshells from eggs of 19 females identified by this method. We used standardised photographs of the eggs laid across three seasons and the computer program “Egg Shell Pattern ANAlysis” (ESPANA). The resulting data were statistically analysed by conducting principal coordinate analyses and analyses of similarity. To prove the identity of the putative females, we extracted DNA for microsatellite analyses from eggshell pieces collected after hatching from up to seven breeding seasons. Our analyses confirmed that Common Cranes lay eggs with individual specific patterns and confirmed the reliability of the semi-quantitative method of identification. Microsatellite genotypes based on nine loci were identical for all samples from each particular, putative female. Therefore, the semi-quantitative approach of identifying females based on their clutches is indeed an innovative monitoring tool that will make many species accessible for addressing important issues in population biology, ecology and conservation. Genetischer Nachweis für individuelle Eierschalenfärbung von Kranichweibchen ( Grus Grus ) Die Vielfalt in der Färbung und Zeichnung von Vogeleiern legt eine Reihe an möglichen Funktionen nahe. So könnte im Fall von intra- oder interspezifischem Brutparasitismus das Erkennen der eigenen Eier eine wichtige Rolle für den Fortpflanzungserfolg der Eltern spielen. Individuell spezifische Signaturen könnten zu dem von Interesse sein, wenn dadurch ein Monitoring von Weibchen währende der Brutzeit ermöglicht würde. Dies wäre von besonderer Bedeutung für die Arten, die nur schwer individuell unterschieden oder markiert werden können, wie beispielsweise den Grauen Kranich ( Grus Grus ). Ein in Norddeutschland laufendes Brutmonitoring führte 2004 zur Entwicklung einer semi-quantitativen Methode, die die Identifizierung von Kranichweibchen anhand von Eiermerkmalen, wie der Eischalengrundfarbe und der Fleckenzeichung ermöglichte. Zur Verifizierung der Methode wurde die Eischalenmusterung von 19 durch sie individuell identifizierten Kranichweibchen quantitativ bestimmt. Grundlage waren standardisierte Fotografien von Eiern aus drei Brutperioden, die mit dem Computerprogramm „Egg Shell Pattern ANAlysis” (ESPANA) analysiert wurden. Die gewonnenen Daten wurden mittels einer Hauptkoordinatenanalyse (PCoA) und einer Ähnlichkeitsanalyse (ANOSIM) statistisch ausgewertet. Um die Identität der angenommen Kranichweibchen zu beweisen, extrahierten wir aus Eierschalenstücken, die nach dem Schlupf der Küken über mehrere Brutperioden gesammelt wurden, DNA für Mikrosatellitenanalysen. Unsere Analysen bestätigten, dass Kranichweibchen Eier mit individuell spezifischen Mustern legen, und damit auch die semi-quantitative Identifizierungsmethode. Die mittels neun Loci bestimmten Genotypen waren für die angenommenen Kranichweibchen über alle Proben identisch. Somit ist die semi-quantitative Methode zur Identifizierung von Kranichweibchen anhand ihrer Gelege ein innovatives Werkzeug zum Monitoring, um auch andere Arten für Fragen der Populationsbiologie, der Ökologie und des Naturschutzes zugänglich zu machen.
-
Genetic evidence of female specific eggshell colouration in the Common Crane ( Grus Grus )
Journal of Ornithology, 2015Co-Authors: Henriette Höltje, Martin Haase, Wolfgang Mewes, Angela Schmitz OrnésAbstract:The large variation in colouration and patterning of bird eggs suggests a variety of functions. For instance, in cases of intra- and inter-specific brood parasitism, the recognition of own eggs by the parents could be essential for their reproductive success. However, individual specific signatures may also be of interest from an applied point of view, as it would be possible to monitor individual females across breeding seasons by identifying their eggs. This would be of particular importance for species that are difficult to catch and ring such as the Common Crane (Grus Grus). Since 2004, nest monitoring of this species has been conducted by one of us (W.M.) in north-east Germany, which led to the development of a semi-quantitative method to identify female cranes by diagnostic egg features including ground colour and spots of eggshells. In order to verify this approach, we quantitatively determined the spot patterns on eggshells from eggs of 19 females identified by this method. We used standardised photographs of the eggs laid across three seasons and the computer program “Egg Shell Pattern ANAlysis” (ESPANA). The resulting data were statistically analysed by conducting principal coordinate analyses and analyses of similarity. To prove the identity of the putative females, we extracted DNA for microsatellite analyses from eggshell pieces collected after hatching from up to seven breeding seasons. Our analyses confirmed that Common Cranes lay eggs with individual specific patterns and confirmed the reliability of the semi-quantitative method of identification. Microsatellite genotypes based on nine loci were identical for all samples from each particular, putative female. Therefore, the semi-quantitative approach of identifying females based on their clutches is indeed an innovative monitoring tool that will make many species accessible for addressing important issues in population biology, ecology and conservation.
Henriette Höltje - One of the best experts on this subject based on the ideXlab platform.
-
Shallow genetic population structure in an expanding migratory bird with high breeding site fidelity, the Western Eurasian Crane Grus Grus Grus
Journal of Ornithology, 2019Co-Authors: Martin Haase, Henriette Höltje, Beate Blahy, Damon Bridge, Eberhard Henne, Ulf S. Johansson, Katrin Kaldma, Ekaterina A. Khudyakova, Amy King, Aivar LeitoAbstract:Geringe genetische Populationsstruktur eines sich ausbreitenden Zugvogels mit hoher Brutortreue, des Westlichen Eurasischen Kranichs, Grus Grus Grus Seit mehr als einem halben Jahrhundert breitet sich der Eurasische Kranich ( Grus Grus Grus ) wieder nach Westeuropa bis hin nach Großbritannien, den Niederlanden und Dänemark aus, wo er ausgerottet war. Der Eurasische Kranich ist einerseits eine sehr mobile, ziehende Art. Andererseits ist er territorial und zeichnet sich durch eine hohe Brutplatztreue aus. Die genetische Populationsstruktur ist somit von gegensätzlichen Kräften mit unterschiedlichen Konsequenzen geprägt. Wir ermittelten die Populationsstruktur der Westeuropäischen Population (WEP) des Eurasischen Kranichs basierend auf sechs hochvariablen Mikrosatelliten-Loci und Samples aus acht Regionen. Wir kombinierten klassische F-Statistik einschließlich molekularer Varianzanzanalysen mit a priori festgelegter Struktur mit divisiven Clusteranalysen—einer Bayes’schen Methode (STRUCTURE) und einer Diskriminanzanalyse von Hauptkomponenten (DAPC)–, die die Struktur a posteriori schätzen. Die F-Statistik zeigte, dass die Populationen nur gering differenziert waren. Der Großteil der genetischen Varianz (> 90%) lag auf Ebene der Individuen. Auf den ersten Blick schienen die divisiven Ansätze ein übereinstimmendes Bild zu zeichnen. Beide fanden vier Cluster. Allerdings gab es keinerlei Übereinstimmung in der Zusammensetzung der Cluster und keines der Resultate war biologisch sinnvoll. STRUCTURE wies allerdings die höchste Wahrscheinlichkeit einem Szenario ohne Populationsunterteilung zu und lieferte somit eine alternative Interpretation, die mit der F-Statistik übereinstimmte. Daher schließen wir, dass die WEP des Eurasischen Kranichs weitestgehend homogen ist. For more than half a century, the Western Eurasian Crane ( Grus Grus Grus ) has been expanding its range toward western Europe, recolonizing areas where it had been previously driven to extinction, including the UK, the Netherlands and Denmark. The Western Eurasian Crane is, on the one hand, a very mobile, migratory species, but on the other, is territorial and shows high breeding site fidelity. Hence, its genetic population structure is subject to antagonizing forces, which have different consequences. Based on the genotyping of six highly variable microsatellite loci, we inferred the population structure of the Western Eurasian Crane from samples from eight regions. We integrated classic F -statistics including analyses of molecular variance with a priori designation of structure and divisive clustering approaches, i.e. a Bayesian procedure (STRUCTURE) and discriminant analysis of principal components, which infer structure a posteriori. According to the F -statistics, populations were only weakly differentiated, and the majority of the genetic variance (> 90%) was attributed to individuals. At first glance, the divisive approaches appeared to agree in finding four clusters. Yet, there was no correspondence regarding the composition of the clusters and none of the results were biologically meaningful. However, STRUCTURE delivered an alternative interpretation, designating the highest likelihood to a scenario without subdivision, in clear agreement with the findings based on the F -statistics. In conclusion, the Western Eurasian Crane is genetically largely homogeneous, probably as a consequence of the rapid growth and range expansion of its population.
-
Shallow genetic population structure in an expanding migratory bird with high breeding site fidelity, the Western Eurasian Crane Grus Grus Grus
Journal of Ornithology, 2019Co-Authors: Martin Haase, Henriette Höltje, Beate Blahy, Damon Bridge, Eberhard Henne, Ulf S. Johansson, Katrin Kaldma, Ekaterina A. Khudyakova, Amy King, Aivar LeitoAbstract:Geringe genetische Populationsstruktur eines sich ausbreitenden Zugvogels mit hoher Brutortreue, des Westlichen Eurasischen Kranichs, Grus Grus Grus Seit mehr als einem halben Jahrhundert breitet sich der Eurasische Kranich ( Grus Grus Grus ) wieder nach Westeuropa bis hin nach Großbritannien, den Niederlanden und Dänemark aus, wo er ausgerottet war. Der Eurasische Kranich ist einerseits eine sehr mobile, ziehende Art. Andererseits ist er territorial und zeichnet sich durch eine hohe Brutplatztreue aus. Die genetische Populationsstruktur ist somit von gegensätzlichen Kräften mit unterschiedlichen Konsequenzen geprägt. Wir ermittelten die Populationsstruktur der Westeuropäischen Population (WEP) des Eurasischen Kranichs basierend auf sechs hochvariablen Mikrosatelliten-Loci und Samples aus acht Regionen. Wir kombinierten klassische F-Statistik einschließlich molekularer Varianzanzanalysen mit a priori festgelegter Struktur mit divisiven Clusteranalysen—einer Bayes’schen Methode (STRUCTURE) und einer Diskriminanzanalyse von Hauptkomponenten (DAPC)–, die die Struktur a posteriori schätzen. Die F-Statistik zeigte, dass die Populationen nur gering differenziert waren. Der Großteil der genetischen Varianz (> 90%) lag auf Ebene der Individuen. Auf den ersten Blick schienen die divisiven Ansätze ein übereinstimmendes Bild zu zeichnen. Beide fanden vier Cluster. Allerdings gab es keinerlei Übereinstimmung in der Zusammensetzung der Cluster und keines der Resultate war biologisch sinnvoll. STRUCTURE wies allerdings die höchste Wahrscheinlichkeit einem Szenario ohne Populationsunterteilung zu und lieferte somit eine alternative Interpretation, die mit der F-Statistik übereinstimmte. Daher schließen wir, dass die WEP des Eurasischen Kranichs weitestgehend homogen ist. For more than half a century, the Western Eurasian Crane ( Grus Grus Grus ) has been expanding its range toward western Europe, recolonizing areas where it had been previously driven to extinction, including the UK, the Netherlands and Denmark. The Western Eurasian Crane is, on the one hand, a very mobile, migratory species, but on the other, is territorial and shows high breeding site fidelity. Hence, its genetic population structure is subject to antagonizing forces, which have different consequences. Based on the genotyping of six highly variable microsatellite loci, we inferred the population structure of the Western Eurasian Crane from samples from eight regions. We integrated classic F -statistics including analyses of molecular variance with a priori designation of structure and divisive clustering approaches, i.e. a Bayesian procedure (STRUCTURE) and discriminant analysis of principal components, which infer structure a posteriori. According to the F -statistics, populations were only weakly differentiated, and the majority of the genetic variance (> 90%) was attributed to individuals. At first glance, the divisive approaches appeared to agree in finding four clusters. Yet, there was no correspondence regarding the composition of the clusters and none of the results were biologically meaningful. However, STRUCTURE delivered an alternative interpretation, designating the highest likelihood to a scenario without subdivision, in clear agreement with the findings based on the F -statistics. In conclusion, the Western Eurasian Crane is genetically largely homogeneous, probably as a consequence of the rapid growth and range expansion of its population.
-
Shallow genetic population structure in an expanding migratory bird with high breeding site fidelity, the Western Eurasian Crane Grus Grus Grus
Journal of Ornithology, 2019Co-Authors: Martin Haase, Henriette Höltje, Beate Blahy, Damon Bridge, Eberhard Henne, Ulf S. Johansson, Katrin Kaldma, Ekaterina A. Khudyakova, Amy King, Aivar LeitoAbstract:For more than half a century, the Western Eurasian Crane (Grus Grus Grus) has been expanding its range toward western Europe, recolonizing areas where it had been previously driven to extinction, including the UK, the Netherlands and Denmark. The Western Eurasian Crane is, on the one hand, a very mobile, migratory species, but on the other, is territorial and shows high breeding site fidelity. Hence, its genetic population structure is subject to antagonizing forces, which have different consequences. Based on the genotyping of six highly variable microsatellite loci, we inferred the population structure of the Western Eurasian Crane from samples from eight regions. We integrated classic F-statistics including analyses of molecular variance with a priori designation of structure and divisive clustering approaches, i.e. a Bayesian procedure (STRUCTURE) and discriminant analysis of principal components, which infer structure a posteriori. According to the F-statistics, populations were only weakly differentiated, and the majority of the genetic variance (> 90%) was attributed to individuals. At first glance, the divisive approaches appeared to agree in finding four clusters. Yet, there was no correspondence regarding the composition of the clusters and none of the results were biologically meaningful. However, STRUCTURE delivered an alternative interpretation, designating the highest likelihood to a scenario without subdivision, in clear agreement with the findings based on the F-statistics. In conclusion, the Western Eurasian Crane is genetically largely homogeneous, probably as a consequence of the rapid growth and range expansion of its population.
-
Genetic evidence of female specific eggshell colouration in the Common Crane (Grus Grus)
Journal of Ornithology, 2016Co-Authors: Henriette Höltje, Martin Haase, Wolfgang Mewes, Angela Schmitz OrnésAbstract:The large variation in colouration and patterning of bird eggs suggests a variety of functions. For instance, in cases of intra- and inter-specific brood parasitism, the recognition of own eggs by the parents could be essential for their reproductive success. However, individual specific signatures may also be of interest from an applied point of view, as it would be possible to monitor individual females across breeding seasons by identifying their eggs. This would be of particular importance for species that are difficult to catch and ring such as the Common Crane ( Grus Grus ). Since 2004, nest monitoring of this species has been conducted by one of us (W.M.) in north-east Germany, which led to the development of a semi-quantitative method to identify female cranes by diagnostic egg features including ground colour and spots of eggshells. In order to verify this approach, we quantitatively determined the spot patterns on eggshells from eggs of 19 females identified by this method. We used standardised photographs of the eggs laid across three seasons and the computer program “Egg Shell Pattern ANAlysis” (ESPANA). The resulting data were statistically analysed by conducting principal coordinate analyses and analyses of similarity. To prove the identity of the putative females, we extracted DNA for microsatellite analyses from eggshell pieces collected after hatching from up to seven breeding seasons. Our analyses confirmed that Common Cranes lay eggs with individual specific patterns and confirmed the reliability of the semi-quantitative method of identification. Microsatellite genotypes based on nine loci were identical for all samples from each particular, putative female. Therefore, the semi-quantitative approach of identifying females based on their clutches is indeed an innovative monitoring tool that will make many species accessible for addressing important issues in population biology, ecology and conservation. Genetischer Nachweis für individuelle Eierschalenfärbung von Kranichweibchen ( Grus Grus ) Die Vielfalt in der Färbung und Zeichnung von Vogeleiern legt eine Reihe an möglichen Funktionen nahe. So könnte im Fall von intra- oder interspezifischem Brutparasitismus das Erkennen der eigenen Eier eine wichtige Rolle für den Fortpflanzungserfolg der Eltern spielen. Individuell spezifische Signaturen könnten zu dem von Interesse sein, wenn dadurch ein Monitoring von Weibchen währende der Brutzeit ermöglicht würde. Dies wäre von besonderer Bedeutung für die Arten, die nur schwer individuell unterschieden oder markiert werden können, wie beispielsweise den Grauen Kranich ( Grus Grus ). Ein in Norddeutschland laufendes Brutmonitoring führte 2004 zur Entwicklung einer semi-quantitativen Methode, die die Identifizierung von Kranichweibchen anhand von Eiermerkmalen, wie der Eischalengrundfarbe und der Fleckenzeichung ermöglichte. Zur Verifizierung der Methode wurde die Eischalenmusterung von 19 durch sie individuell identifizierten Kranichweibchen quantitativ bestimmt. Grundlage waren standardisierte Fotografien von Eiern aus drei Brutperioden, die mit dem Computerprogramm „Egg Shell Pattern ANAlysis” (ESPANA) analysiert wurden. Die gewonnenen Daten wurden mittels einer Hauptkoordinatenanalyse (PCoA) und einer Ähnlichkeitsanalyse (ANOSIM) statistisch ausgewertet. Um die Identität der angenommen Kranichweibchen zu beweisen, extrahierten wir aus Eierschalenstücken, die nach dem Schlupf der Küken über mehrere Brutperioden gesammelt wurden, DNA für Mikrosatellitenanalysen. Unsere Analysen bestätigten, dass Kranichweibchen Eier mit individuell spezifischen Mustern legen, und damit auch die semi-quantitative Identifizierungsmethode. Die mittels neun Loci bestimmten Genotypen waren für die angenommenen Kranichweibchen über alle Proben identisch. Somit ist die semi-quantitative Methode zur Identifizierung von Kranichweibchen anhand ihrer Gelege ein innovatives Werkzeug zum Monitoring, um auch andere Arten für Fragen der Populationsbiologie, der Ökologie und des Naturschutzes zugänglich zu machen.
-
Genetic evidence of female specific eggshell colouration in the Common Crane ( Grus Grus )
Journal of Ornithology, 2015Co-Authors: Henriette Höltje, Martin Haase, Wolfgang Mewes, Angela Schmitz OrnésAbstract:The large variation in colouration and patterning of bird eggs suggests a variety of functions. For instance, in cases of intra- and inter-specific brood parasitism, the recognition of own eggs by the parents could be essential for their reproductive success. However, individual specific signatures may also be of interest from an applied point of view, as it would be possible to monitor individual females across breeding seasons by identifying their eggs. This would be of particular importance for species that are difficult to catch and ring such as the Common Crane (Grus Grus). Since 2004, nest monitoring of this species has been conducted by one of us (W.M.) in north-east Germany, which led to the development of a semi-quantitative method to identify female cranes by diagnostic egg features including ground colour and spots of eggshells. In order to verify this approach, we quantitatively determined the spot patterns on eggshells from eggs of 19 females identified by this method. We used standardised photographs of the eggs laid across three seasons and the computer program “Egg Shell Pattern ANAlysis” (ESPANA). The resulting data were statistically analysed by conducting principal coordinate analyses and analyses of similarity. To prove the identity of the putative females, we extracted DNA for microsatellite analyses from eggshell pieces collected after hatching from up to seven breeding seasons. Our analyses confirmed that Common Cranes lay eggs with individual specific patterns and confirmed the reliability of the semi-quantitative method of identification. Microsatellite genotypes based on nine loci were identical for all samples from each particular, putative female. Therefore, the semi-quantitative approach of identifying females based on their clutches is indeed an innovative monitoring tool that will make many species accessible for addressing important issues in population biology, ecology and conservation.
Gunter Nowald - One of the best experts on this subject based on the ideXlab platform.
-
Migration and wintering patterns of a central European population of Common Cranes Grus Grus
Bird Study, 2008Co-Authors: Javier A. Alonso, Juan C. Alonso, Gunter NowaldAbstract:Capsule German breeding birds wintered mainly in southwest Spain and some in France. Aims To describe migration routes and phenology, and the interannual fidelity to staging and wintering sites. Methods A total of 93 cranes were colour-banded, and 67 of them radiotagged, at their breeding territories in northern Germany and later located at their wintering areas in Spain. Results After a migratory trip lasting 3‐28 days, most cranes arrived at Gallocanta in northeastern Spain, where they staged for 1‐44 days. Some families stayed there the whole winter, but most continued to southwestern Iberia, where they dispersed over at least 13 wintering areas. Site fidelity was more marked in adult pairs than immatures, half of which used different areas in their second and third winters from those used by their parents. Conclusions Most German cranes wintered in southwestern Spain, with smaller numbers in France. Some immatures remained in France as second- or third-year birds, after having spent their first winter in Spain with their parents, whereas none of them shifted southwards. This suggests that immatures have probably contributed more than adult pairs to the northward shift in the winter range observed during the last decades.
-
Verhalten von Kranichfamilien (Grus Grus) in Brutrevieren Nordostdeutschlands: Investition der Altvögel in ihre Nachkommen
Journal für Ornithologie, 2001Co-Authors: Gunter NowaldAbstract:Juveniles and immature birds normally have less foraging ability and a lower food intake rate than adults. This — it has been presumed — is compensated for by parental care and investment during juvenile development. Studies of time budgets and parental investment of Common Cranes were carried out in the years 1995 to 1999 in Northeast Germany. Having first marked young Cranes (colour rings, radio transmitters), we analysed the behaviour of parents and offspring to correlate this with reproductive success. Parents with young (39.6%) were four times more vigilant than non-breeders. The investment of pairs with two young was significantly (p
-
Verhalten von Kranichfamilien (Grus Grus) in Brutrevieren Nordostdeutschlands: Investition der Altvögel in ihre Nachkommen
Journal für Ornithologie, 2001Co-Authors: Gunter NowaldAbstract:Junge Graukraniche haben einen weniger guten Jagderfolg bzw. eine geringere Rate bei der Nahrungsaufnahme als Altvögel. Dieses Defizit sollte durch die elterliche Investition bei der Jungenaufzucht kompensiert werden. Untersuchungen zum Zeitbudget und zum Aufwand aus dem Brutgebiet fehlen bisher. Mit Hilfe markierter Jungkraniche (Farbringe, Sender) wurde das Verhalten der Eltern und ihrer Nachkommen erfasst, um die Investitionen in Beziehung zum Reproduktionserfolg zu analysieren. Die Eltern sicherten mit 39,6% fast viermal so häufig wie Altvögel ohne Junge (Übersommerer). Bei Paaren mit zwei Nachkommen waren diese Aufwendungen höher als bei Paaren mit nur einem Jungvogel. Das Weibchen profitierte vom verstärkten Sichern des Männchens (Männchen: durchschnittlich 43,9%, Weibchen 35,3%) und konnte so vermutlich schneller seine Investition in die Gelegeproduktion ausgleichen. Die Revierverteidigung bzw. Feindabwehr übernahmen meist die Männchen. Die Beteiligung des Männchens förderte den Aufzuchterfolg, der auf zwei Junge begrenzt ist. Die Jungen profitierten von den Leistungen ihrer Eltern. Sie konnten mit geringem Sicherungsaufwand (11,9%) Nahrung suchen (67,7%, Eltern 42,8%) und so ihre geringere Aufnahmerate kompensieren. 77,9% der Jungkraniche überlebten vom Zeitpunkt des Markierens im Juni bis zum Abzug ins Überwinterungsgebiet im Oktober/November (84% der Einzeljungen und 75% bei Familien mit zwei Nachkommen). Junge Kraniche müssen einen wesentlichen Teil des Tages Nahrung aufnehmen, um den Energiebedarf für ein schnelles Wachstum sicherzustellen. Bei einer negativen Energiebilanz aufgrund zu vieler Störreize können die Erfolge bei der Jungenaufzucht sinken. Im Rahmen der Landschaftsplanung ist vor allem in Räumen mit einer hohen Siedlungsdichte des Kranichs auf eine stärkere Bebauung (z. B. mit Windkraftanlagen) oder Zerschneidung durch weitere Verkehrswege und Energieleitungen zu verzichten. Juveniles and immature birds normally have less foraging ability and a lower food intake rate than adults. This — it has been presumed — is compensated for by parental care and investment during juvenile development. Studies of time budgets and parental investment of Common Cranes were carried out in the years 1995 to 1999 in Northeast Germany. Having first marked young Cranes (colour rings, radio transmitters), we analysed the behaviour of parents and offspring to correlate this with reproductive success. Parents with young (39.6%) were four times more vigilant than non-breeders. The investment of pairs with two young was significantly (p
Zhilong Zheng - One of the best experts on this subject based on the ideXlab platform.
-
ICNP - Grus: Enabling Latency SLOs for GPU-Accelerated NFV Systems
2018 IEEE 26th International Conference on Network Protocols (ICNP), 2018Co-Authors: Zhilong Zheng, Haiping Wang, Hongxin Hu, Heng Yu, Jun Bi, Jianping WuAbstract:Graphics Processing Unit (GPU) has been recently exploited as a hardware accelerator to improve the performance of Network Function Virtualization (NFV). However, GPU-accelerated NFV systems suffer from significant latency variation when multiple network functions (NFs) are co-located in the same machine, which prevents operators from supporting latency Service Level Objectives (SLOs). Existing research efforts to address this problem can only guarantee a limited number of SLOs with very low resource utilization efficiency. In this paper, we present the Grus framework to support latency SLOs in GPU-accelerated NFV systems. Grus thoroughly analyzes the sources of latency variation and proposes three design principles: (1) dynamic batch size setting is needed to bound packet batching latency in CPU; (2) a reordering mechanism for data transfer over PCI-E is required to guarantee the stalling time; and (3) maximizing concurrency in GPU is necessary to avoid NF execution waiting time. Guided by the principles, Grus consists of two logical layers including an infrastructure layer and a scheduling layer. The infrastructure layer is equipped with an in-CPU Reorder-able Worker Pool that could adjust batching size and packet transfer order, and in-GPU Controllable Concurrent Executors to provide maximized concurrency. The scheduling layer runs a heuristic algorithm to perform accurate and fast scheduling to guarantee SLOs based on our prediction models. We have implemented a prototype of Grus. Extensive evaluations demonstrate that Grus can significantly reduce latency variation and satisfy 4.5× more SLO terms than state-of-the-art solutions.
-
Grus enabling latency slos for gpu accelerated nfv systems
International Conference on Network Protocols, 2018Co-Authors: Zhilong Zheng, Haiping Wang, Chen Sun, Kai GaoAbstract:Graphics Processing Unit (GPU) has been recently exploited as a hardware accelerator to improve the performance of Network Function Virtualization (NFV). However, GPU-accelerated NFV systems suffer from significant latency variation when multiple network functions (NFs) are co-located in the same machine, which prevents operators from supporting latency Service Level Objectives (SLOs). Existing research efforts to address this problem can only guarantee a limited number of SLOs with very low resource utilization efficiency. In this paper, we present the Grus framework to support latency SLOs in GPU-accelerated NFV systems. Grus thoroughly analyzes the sources of latency variation and proposes three design principles: (1) dynamic batch size setting is needed to bound packet batching latency in CPU; (2) a reordering mechanism for data transfer over PCI-E is required to guarantee the stalling time; and (3) maximizing concurrency in GPU is necessary to avoid NF execution waiting time. Guided by the principles, Grus consists of two logical layers including an infrastructure layer and a scheduling layer. The infrastructure layer is equipped with an in-CPU Reorder-able Worker Pool that could adjust batching size and packet transfer order, and in-GPU Controllable Concurrent Executors to provide maximized concurrency. The scheduling layer runs a heuristic algorithm to perform accurate and fast scheduling to guarantee SLOs based on our prediction models. We have implemented a prototype of Grus. Extensive evaluations demonstrate that Grus can significantly reduce latency variation and satisfy 4.5× more SLO terms than state-of-the-art solutions.
