Abstract
Wind is an important selective agent in bird migration. In this study, we investigated the influence of wind on the air speed of pelagic seabirds in the Strait of Gibraltar by means of radar measurements. The birds were identified visually at the species level. A total of 354 radar tracks of migrating birds were analysed, with an average tracking time of 147 s per target. An interspecific comparison under negligible wind speeds showed a slight increase of air speed in the order from Cory’s Shearwater, a typically gliding species (12.8 m s−1), Balearic Shearwater (gliding with flapping, 14.7 m s−1), gannets (flap-gliding, 15.0 m s−1), Great Skua (flapping, 16.0 m s−1) to auks (fast flapping, 17.4 m s−1). All of the studied species decreased their air speed with increasing wind increment (ground speed minus air speed), and this occurred in following winds slightly less than in opposing winds. Auks adjusted air speed to wind increment only in opposing winds, suggesting that auks are not able to reduce their high air speed in following winds due to extremely high wing loading.
Zusammenfassung
Fluggeschwindigkeiten ziehender Meeresvögel in der Strasse von Gibraltar in Relation zum Wind
Während einer Frühlings- und einer Herbstzugperiode wurden auf dem Plan-Positions-Indikator eines auf der Südspitze von Tarifa positionierten S-Band-Schiffradars die Flugwege ziehender Meeresvögel aufgezeichnet. Gleichzeitig wurde deren Artzugehörigkeit durch Feldbeobachter bestimmt. Stündliche Windmessungen auf der Flughöhe der Vögel erlaubten es, den Einfluss des Windes auf die Eigengeschwindigkeit der pelagischen Zugvögel zu untersuchen. 354 Flugwege mit einer durchschnittlichen Aufzeichnungsdauer von 147 s wurden analysiert. Ein interspezifischer Vergleich unter vernachlässigbaren Windgeschwin-digkeiten zeigte eine leichte Zunahme der Eigengeschwindigkeit vom Gelbschnabel-Sturmtaucher (einem typischen dynamischen Gleiter mit 12.8 m s−1) über den Balearen-Sturmvogel (Gleiter mit Flügelschlägen: 14.7 m s−1), bis zu Basstölpel (Schlag- und Gleitflug: 15.0 m s−1), Skua (Schlagflug: 16.0 m s−1) und Alken (rascher Schlagflug: 17.4 m s−1). All diese Arten senkten ihre Eigengeschwindigkeit wenn die Differenz zwischen ihrer Geschwindigkeit über Grund und ihrer Eigengeschwindigkeit zunahm. Der Effekt war besonders stark bei abnehmendem Gegenwind, etwas weniger stark bei zunehmendem Rückenwind. Alken (Tordalk und Papageitaucher) passten ihre Eigengeschwindigkeit nur bei abnehmendem Gegenwind an. Es scheint, dass sie aufgrund der extrem hohen Flächen-belastung ihrer Flügel nicht in der Lage sind, ihre Eigengeschwindigkeit unter die Geschwindigkeit bei Windstille zu senken.
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Notes
Considering the wide variation in the angles of attack of the wind (60°), one might be inclined to talk about opposing and following winds; however, we decided to use the established terms head- and tailwind in this first approach.
References
Alerstam T (1976) Bird migration in relation to wind and topography. PhD thesis. University of Lund, Lund
Alerstam T (1979) Wind as selective agent in bird migration. Ornis Scand 10:76–93
Alerstam T (1990) Bird migration. Cambridge University Press, England
Alerstam T, Gudmundsson GA, Larsson B (1993) Flight tracks and speeds of Antarctic and Atlantic seabirds: radar and optical instruments. Philos Trans R Soc Lond B Biol Sci 340:55–67
Balance LT (1995) Flight energetic of free ranging red-footed boobies (Sula sula). Physiol Zool 68:887–914
Batschelet E (1981) Circular statistics in biology. Academic Press, New York
Bruderer B (1971) Radarbeobachtungen über den Frühlingszug im Schweizerischen Mittelland. (Ein Beitrag zum Problem der Witterungsabhängigkeit des Vogelzuges). Ornithol Beobachter 68:89–158
Bruderer B (1997) The study of bird migration by radar. Part 1: the technical basis. Naturwissenschaften 84:1–8
Environmental Systems Research Institute (1999) ArcView GIS 3.2. Environmental Systems Research Institute, Redlands
Gudmundsson GA, Alerstam T, Larsson B (1992) Radar observations of northbound migration of the Arctic Tern Sterna paradisaea, at the Antarctic Peninsula. Antarct Sci 4:163–170
Hashmi D (2000) Opportunities for monitoring seabirds and cetaceans in the Strait of Gibraltar. In: Proceedings of 5th Medmaravis Symposium, Gozo, Malta, pp 176–191
Hedenström A, Alerstam T, Green M, Gudmundsson GA (2002) Adaptive variation of air speed in relation to wind, altitude and climb rate by migrating birds in the Arctic. Behav Ecol Sociobiol 52:308–317
Kovack Computing Services (2007) Oriana Version 2.02e. Kovack Computing Services, Anglesey
Krüger T, Garthe S (2001) Flight altitudes of coastal birds in relation to wind direction and speed. Atl Seab 3:203–216
Liechti F (1995) Modelling optimal heading and airspeed of migrating birds in relation to energy expenditure and wind influence. J Avian Biol 26:330–336
Mateos M (2009) Radar technology applied to the study of seabird migration across the Strait of Gibraltar. PhD thesis. University of Cadiz, Cadiz
Mateos M, Arroyo GM (2011) Ocean surface winds drive local-scale movements within long-distance migrations of seabirds. Mar Biol 158:329–339
Mateos M, Bruderer B (2010) Anwendung von Radar für das Studium des Zuges von Meeresvögeln durch die Strasse von Gibraltar. Der Ornithol Beobachter 107:179–190
Mateos M, Arroyo GM, Rodríguez A, Cuenca D, de la Cruz A (2010) Calibration of visually estimated distances to migrating seabirds with radar measurements. J Field Ornithol 81(3):302–309
Meseguer J, Álvarez JC, Pérez A (2004) Formas de retrasar la entrada en pérdidas en las alas de las aves. Instituto Universitario de Microgravedad “Ignacio Da Riva”. Report no. IDR/PA 0104. Universidad Politécnica de Madrid, Madrid
Migres Programa (2009) Seguimiento de la migración de las aves en el Estrecho de Gibraltar: resultados del Programa Migres 2008. Migres Rev Ecol 1:83–101
Newton I (2008) The migration ecology of birds. Academic Press, London
Pennycuick CJ (1982) The flight of petrels and albatrosses (Procellariiformes), observed in South Georgia and its vicinity. Philos Trans R Soc Lond B Biol Sci 300:75–106
Pennycuick CJ (1987) Flight of Auks (Alcidae) and other northern seabirds compared with southern Procellariiformes: ornithodolite observations. J Exp Biol 128:335–347
Pennycuick CJ (1989) Bird flight performance: a practical calculation manual. Oxford University Press, Oxford
Pennycuick CJ (1990) Predicting wingbeat frequency and wavelength of birds. J Exp Biol 150:171–185
Pennycuick CJ (1996) Wingbeat frequency of birds in steady cruising flight: new data and improved predictions. J Exp Biol 199:1613–1618
Pennycuick CJ (2008) Modelling the flying bird. Academic press, London
R Development Core Team (2008) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna
Roots C (2006) Flightless birds. Greenwood Press, London
Shamoun-Baranes J, van Loon E, Liechti F, Bouten W (2007) Analyzing the effect of wind on flight: pitfalls and solutions. J Exp Biol 210:82–90
Spear LB, Ainley DG (1997) Flight speed of seabirds in relation to wind speed and direction. Ibis 139:234–251
Warham J (1977) Wing loadings, wing shapes, and flight capabilities of Procellariiformes. N Z J Zool 4:73–83
Acknowledgments
This study was conducted within a collaboration agreement between the Migres Foundation and the University of Cadiz. The radar facilities were supplied by Ceowind Capital Energy Off-shore Company. María Mateos-Rodríguez was granted a FPU fellowship by the Junta de Andalucía, and Dr. Gonzalo M. Arroyo supervised her thesis. We thank the Migres Foundation technical staff for their help in the fieldwork and Dr. Gonzalo M. Arroyo, Dr. M. Ferrer, Dr. J. González-Solís, Dr. G.A. Gudmundsson, Dr. F. Liechti and Dr. J. Shamoun-Baranes and one anonymous referee for their comments and suggestions on previous versions of this manuscript.
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Communicated by A. Hedenström.
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Mateos-Rodríguez, M., Bruderer, B. Flight speeds of migrating seabirds in the Strait of Gibraltar and their relation to wind. J Ornithol 153, 881–889 (2012). https://doi.org/10.1007/s10336-012-0814-6
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DOI: https://doi.org/10.1007/s10336-012-0814-6