Abstract
Radar tracks of individual birds migrating on overcast nights were compared with a similar set of tracks obtained under clear skies. I examined the accuracy of orientation within and among tracks, flight altitude and changes in altitude, the effects of flying within clouds, and the effects of continuous overcast of several days’ duration. When birds were flying below the cloud cover there were essentially no discernible effects. Their flight was as straight, level, and fast as comparable birds flying on clear nights. Likewise, the spread in headings among birds was similar. On each of four nights when birds appeared to be flying within or between cloud layers, headings were random and the individual tracks were slightly, but significantly less straight than when birds were flying beneath the clouds. Uninterrupted overcast of several days’ duration did not result in random headings so long as the birds were flying below the cloud ceiling.
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References
Able KP (1974) Environmental influences on the orientation of free-flying nocturnal bird migrants. Anim Behav 22: 224–238
Able KP (1978) Field studies of the orientation cue hierarchy of nocturnal songbird migrants. In: Schmidt-Koenig K, Keeton WT (eds) Animal migration, navigation, and homing. Springer, Berlin Heidelberg New York, p 228
Able KP (1980a) Mechanisms of orientation, navigation and homing. In: Gauthreaux SA (ed) Animal migration, orientation, and navigation. Academic Press, London New York, p 325.
Able KP (1980b) Evidence on migratory orientation from radar and visual observations: North America. Acta XVIIth Congr Int Ornithol. Dtsch Ornithol Ges, Berlin
Able KP (1982) Field studies on avian nocturnal migratory orientation. I. Interaction of sun, wind and stars as directional cues. Anim Behav (in press)
Batschelet E (1965) Statistical methods for the analysis of problems in animal orientation and certain biological rhythms. AIBS Monogr, Washington DC
Batschelet E (1972) Recent statistical methods for orientation data. In: Animal orientation and navigation. NASA Spec Pub1–262, US Gov Print Off, Washington DC, p 61
Bellrose FC (1967) Radar in orientation research. Proc XIVth Int Ornithol Congr, p 281 Bellrose FC, Graber RR ( 1963 ) A radar study of the flight direction of nocturnal migrants. Proc XIIIth Int Ornithol Congr, p 362
Bellrose FC, Graber RR ( 1963 ) A radar study of the flight direction of nocturnal migrants. Proc XIIIth Int Ornithol Congr, p 362
Bingman VP, Able KP, Kerlinger P (1982) Wind drift, compensation, and the use of landmarks by nocturnal bird migrants. Anim Behav 30: 49–53
Chernosky EJ, Fougere PF, Hutchinson RO (1965) The geomagnetic field. In: Valley SL (ed) Handbook of geophysics and space environments. McGraw Hill, New York, p 11
Cochran WW, Montgomery GG, Graber RR (1967) Migratory flights of Hylocichla thrushes in spring: a radiotelemetry study. Living Bird 6:213–225
Drury WH, Nisbet ICT (1964) Radar studies of orientation of songbird migrants in southestern New England. Bird-Banding 35: 69–119
Emlen ST (1975) Migration: orientation and navigation. In: Farner DS, King JR (eds) Avian biology, vol V. Academic Press, London New York, p 129
Griffin DR (1973) Oriented bird migration in or between opaque cloud layers. Proc Am Philos Soc 117: 117–141
Hebrard JJ (1971) Fall nocturnal migration during two successive overcast days. Condor 74: 106–107
Keeton WT (1974) The orientational and navigational basis of homing in birds. Adv Study Behav 5: 47–132
Lack D (1962) Radar evidence on migratory orientation. Br Birds 55: 139–158
Moore FR (1980) Solar cues in the migratory orientation of the savannah sparrow, Passerculus sandwichensis. Anim Behav 28: 684–704
Wiltschko R, Wiltschko W (1978) Relative importance of stars and the magnetic field for the accuracy of orientation in night-migratory birds. Oikos 30: 195–206
Wiltschko W, Wiltschko R (1975a) The interaction of stars and magnetic field in the orientation system of night migrating birds. I. Autumn experiments with European warblers (Gen. Sylvia). Z Tierpsychol 37: 337–355
Wiltschko W, Wiltschko R (1975b) The interaction of stars and magnetic field in the orientation system of night migrating birds. II. Spring experiments with European robins (Erithacus rube-cula). Z Tierpsychol 39:265 —282
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© 1982 Springer-Verlag Berlin Heidelberg
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Able, K.P. (1982). The Effects of Overcast Skies on the Orientation of Free-Flying Nocturnal Migrants. In: Papi, F., Wallraff, H.G. (eds) Avian Navigation. Proceedings in Life Sciences. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-68616-0_4
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DOI: https://doi.org/10.1007/978-3-642-68616-0_4
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