Bird orientation at high latitudes: flight routes between Siberia and North America across the Arctic Ocean
Bird migration and orientation at high latitudes are of special interest because of the difficulties associated with different compass systems in polar areas and because of the considerable differences between flight routes conforming to loxodromes (rhumblines) or orthodromes (great circle routes)....
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ftpubmed:oai:pubmedcentral.nih.gov:1690484 2023-05-15T14:50:23+02:00 Bird orientation at high latitudes: flight routes between Siberia and North America across the Arctic Ocean Alerstam, T Gudmundsson, GA 1999-12-22 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1690484 http://www.ncbi.nlm.nih.gov/pubmed/10693821 en eng http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1690484 http://www.ncbi.nlm.nih.gov/pubmed/10693821 Research Article Text 1999 ftpubmed 2013-08-31T12:32:30Z Bird migration and orientation at high latitudes are of special interest because of the difficulties associated with different compass systems in polar areas and because of the considerable differences between flight routes conforming to loxodromes (rhumblines) or orthodromes (great circle routes). Regular and widespread east-north-east migration of birds from the northern tundra of Siberia towards North America across the Arctic Ocean (without landmark influences) were recorded by ship-based tracking radar studies in July and August. Field observations indicated that waders, including species such as Phalaropusfulicarius and Calidris melanotos, dominated, but also terns and skuas may have been involved. Analysis of flight directions in relation to the wind showed that these movements are not caused by wind drift. Assuming possible orientation principles based on celestial or geomagnetic cues, different flight trajectories across the Arctic Ocean were calculated: geographical loxodromes, sun compass routes, magnetic loxodromes and magnetoclinic routes. The probabilities of these four alternatives are evaluated on the basis of both the availability of required orientation cues and the predicted flight paths. This evaluation supports orientation along sun compass routes. Because of the longitudinal time displacement sun compass routes show gradually changing compass courses in close agreement with orthodromes. It is suggested that an important migration link between Siberia and North American stopover sites 1000-2500km apart across the Arctic Ocean has evolved based on sun compass orientation along orthodrome-like routes. Text Arctic Arctic Ocean Tundra Siberia PubMed Central (PMC) Arctic Arctic Ocean |
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Research Article Alerstam, T Gudmundsson, GA Bird orientation at high latitudes: flight routes between Siberia and North America across the Arctic Ocean |
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Research Article |
description |
Bird migration and orientation at high latitudes are of special interest because of the difficulties associated with different compass systems in polar areas and because of the considerable differences between flight routes conforming to loxodromes (rhumblines) or orthodromes (great circle routes). Regular and widespread east-north-east migration of birds from the northern tundra of Siberia towards North America across the Arctic Ocean (without landmark influences) were recorded by ship-based tracking radar studies in July and August. Field observations indicated that waders, including species such as Phalaropusfulicarius and Calidris melanotos, dominated, but also terns and skuas may have been involved. Analysis of flight directions in relation to the wind showed that these movements are not caused by wind drift. Assuming possible orientation principles based on celestial or geomagnetic cues, different flight trajectories across the Arctic Ocean were calculated: geographical loxodromes, sun compass routes, magnetic loxodromes and magnetoclinic routes. The probabilities of these four alternatives are evaluated on the basis of both the availability of required orientation cues and the predicted flight paths. This evaluation supports orientation along sun compass routes. Because of the longitudinal time displacement sun compass routes show gradually changing compass courses in close agreement with orthodromes. It is suggested that an important migration link between Siberia and North American stopover sites 1000-2500km apart across the Arctic Ocean has evolved based on sun compass orientation along orthodrome-like routes. |
format |
Text |
author |
Alerstam, T Gudmundsson, GA |
author_facet |
Alerstam, T Gudmundsson, GA |
author_sort |
Alerstam, T |
title |
Bird orientation at high latitudes: flight routes between Siberia and North America across the Arctic Ocean |
title_short |
Bird orientation at high latitudes: flight routes between Siberia and North America across the Arctic Ocean |
title_full |
Bird orientation at high latitudes: flight routes between Siberia and North America across the Arctic Ocean |
title_fullStr |
Bird orientation at high latitudes: flight routes between Siberia and North America across the Arctic Ocean |
title_full_unstemmed |
Bird orientation at high latitudes: flight routes between Siberia and North America across the Arctic Ocean |
title_sort |
bird orientation at high latitudes: flight routes between siberia and north america across the arctic ocean |
publishDate |
1999 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1690484 http://www.ncbi.nlm.nih.gov/pubmed/10693821 |
geographic |
Arctic Arctic Ocean |
geographic_facet |
Arctic Arctic Ocean |
genre |
Arctic Arctic Ocean Tundra Siberia |
genre_facet |
Arctic Arctic Ocean Tundra Siberia |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1690484 http://www.ncbi.nlm.nih.gov/pubmed/10693821 |
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1766321411442343936 |