Bruno Bruderer - Academia.edu (original) (raw)
Papers by Bruno Bruderer
Journal of Ornithology, 2011
... to cross a desert Susanne Jenni-Eiermann Bettina Almasi Ivan Maggini Volker Salewski ... more ... to cross a desert Susanne Jenni-Eiermann Bettina Almasi Ivan Maggini Volker Salewski Bruno Bruderer Felix Liechti Lukas Jenni Received: 14 June 2010 / Revised: 12 July 2010 / Accepted: 27 July 2010 / Published online: 19 August 2010 Ó Dt. ...
Proceedings in Life Sciences, 1978
Bruderer, B. (2001): Recent studies modifying current views of nocturnal bird migration in the Me... more Bruderer, B. (2001): Recent studies modifying current views of nocturnal bird migration in the Mediterranean. Avian Ecol. Behav. 7: 11-25. Field observations by radar, infrared, and moon-watching provide a general view of the horizontal distribution and directions of nocturnal migration in the Mediterranean. Obser- vations at particular sites show adjustments of directions to topography, at some sites varying with the
Http Dx Doi Org 10 1080 00306525 1994 9639683, Oct 19, 2010
Naturwissenschaften, 1997
Journal of Ornithology, 2012
Wind is an important selective agent in bird migration. In this study, we investigated the influe... more 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.
Proceedings in Life Sciences, 1982
Avian Migration, 2003
ABSTRACT The history and methodology of radar ornithology was comprehensively reviewed by Eastwoo... more ABSTRACT The history and methodology of radar ornithology was comprehensively reviewed by Eastwood (1967) and updated by Bruderer (1997a). The present chapter gives an outline of the possibilities and limitations of the method, summarizes the main fields of research, and indicates recent achievements as well as chances for the future.
Bird Migration, 1990
... Page 5. 64 R. Bruderer and L.Jenni мэ m OJ ol - ol Ol ol ЧЭ in Г Ш 42 >л Ol CO ol cj Ol ... more ... Page 5. 64 R. Bruderer and L.Jenni мэ m OJ ol - ol Ol ol ЧЭ in Г Ш 42 >л Ol CO ol cj Ol OlOl r« CI Ol Л и го in Ol Ol Ol гп О оо О Ol ol о! ... Ol гч Ol Ol ^Г Ol < H On in Tt С Ol СО О Ol о OlOl i■ On in OIO OOO ^ О Ol Tf Ol Tf Ol rt Ol Ol Ol Ol Ol Ol Ol OJ Ol Ol О Ol rt чн ...
Ostrich, 1994
... heron-and gull-type birds. The propomon of waders and waterfowl identified by wing-beat atter... more ... heron-and gull-type birds. The propomon of waders and waterfowl identified by wing-beat attern in nocturnal migration is nearly the Same at both sites, indicating broad-front migration across tie desert. The numbers of buds with ...
Ostrich, 1993
Bruderer B. & Bruderer H. 1993. Distribution and habitat preference of Redbacked Shrikes ... more Bruderer B. & Bruderer H. 1993. Distribution and habitat preference of Redbacked Shrikes Lanius collurio in southern Africa. Ostrich 64: 141–147.Reporting rates of Redbacked Shrikes provided by the Southern African Bird Atlas Project (SABAP) an the Botswana Bird Atlas are combined in a distribution map covering the area south of the Kunene and Zambesi rivers. The species' main distribution south
Naturwissenschaften, 1997
Journal of Ornithology, 1999
Journal of Ornithology, 2007
Moult data from 302 museum skins and 11 trapped birds from sub-Saharan Africa show the course of ... more Moult data from 302 museum skins and 11 trapped birds from sub-Saharan Africa show the course of flight feather moult. Most birds seem to start flight-feather moult soon after arrival in their southern African nonbreeding ranges. About 75% of the birds had started before mid-December, i.e., during the main arrival time of the species. The mode of moult scores 1 and 2 was reached on 7 December; the last birds with a score of zero occurred in the first days of January. The mode of moult scores 5 and 6 was reached on 27 February. Thus, the time elapsed between the days when 50% of the population had reached the first and last stages of recorded moult was about 82 days; nine days later 75% had reached this last stage before moult was completed. Thus, individual moult may be estimated to cover about 80-90 days. The main moulting period is between mid-November and mid-March, thus covering about four months. No temporal difference was detected between males and females. A tendency for an advancement of adults compared to young birds was not statistically significant. According to the progress of the moult, sexing of young birds in the field is possible for 50% of the birds towards the end of January and for most birds before mid-February.
Journal of Ornithology, 2011
... to cross a desert Susanne Jenni-Eiermann Bettina Almasi Ivan Maggini Volker Salewski ... more ... to cross a desert Susanne Jenni-Eiermann Bettina Almasi Ivan Maggini Volker Salewski Bruno Bruderer Felix Liechti Lukas Jenni Received: 14 June 2010 / Revised: 12 July 2010 / Accepted: 27 July 2010 / Published online: 19 August 2010 Ó Dt. ...
Proceedings in Life Sciences, 1978
Bruderer, B. (2001): Recent studies modifying current views of nocturnal bird migration in the Me... more Bruderer, B. (2001): Recent studies modifying current views of nocturnal bird migration in the Mediterranean. Avian Ecol. Behav. 7: 11-25. Field observations by radar, infrared, and moon-watching provide a general view of the horizontal distribution and directions of nocturnal migration in the Mediterranean. Obser- vations at particular sites show adjustments of directions to topography, at some sites varying with the
Http Dx Doi Org 10 1080 00306525 1994 9639683, Oct 19, 2010
Naturwissenschaften, 1997
Journal of Ornithology, 2012
Wind is an important selective agent in bird migration. In this study, we investigated the influe... more 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.
Proceedings in Life Sciences, 1982
Avian Migration, 2003
ABSTRACT The history and methodology of radar ornithology was comprehensively reviewed by Eastwoo... more ABSTRACT The history and methodology of radar ornithology was comprehensively reviewed by Eastwood (1967) and updated by Bruderer (1997a). The present chapter gives an outline of the possibilities and limitations of the method, summarizes the main fields of research, and indicates recent achievements as well as chances for the future.
Bird Migration, 1990
... Page 5. 64 R. Bruderer and L.Jenni мэ m OJ ol - ol Ol ol ЧЭ in Г Ш 42 >л Ol CO ol cj Ol ... more ... Page 5. 64 R. Bruderer and L.Jenni мэ m OJ ol - ol Ol ol ЧЭ in Г Ш 42 >л Ol CO ol cj Ol OlOl r« CI Ol Л и го in Ol Ol Ol гп О оо О Ol ol о! ... Ol гч Ol Ol ^Г Ol < H On in Tt С Ol СО О Ol о OlOl i■ On in OIO OOO ^ О Ol Tf Ol Tf Ol rt Ol Ol Ol Ol Ol Ol Ol OJ Ol Ol О Ol rt чн ...
Ostrich, 1994
... heron-and gull-type birds. The propomon of waders and waterfowl identified by wing-beat atter... more ... heron-and gull-type birds. The propomon of waders and waterfowl identified by wing-beat attern in nocturnal migration is nearly the Same at both sites, indicating broad-front migration across tie desert. The numbers of buds with ...
Ostrich, 1993
Bruderer B. & Bruderer H. 1993. Distribution and habitat preference of Redbacked Shrikes ... more Bruderer B. & Bruderer H. 1993. Distribution and habitat preference of Redbacked Shrikes Lanius collurio in southern Africa. Ostrich 64: 141–147.Reporting rates of Redbacked Shrikes provided by the Southern African Bird Atlas Project (SABAP) an the Botswana Bird Atlas are combined in a distribution map covering the area south of the Kunene and Zambesi rivers. The species' main distribution south
Naturwissenschaften, 1997
Journal of Ornithology, 1999
Journal of Ornithology, 2007
Moult data from 302 museum skins and 11 trapped birds from sub-Saharan Africa show the course of ... more Moult data from 302 museum skins and 11 trapped birds from sub-Saharan Africa show the course of flight feather moult. Most birds seem to start flight-feather moult soon after arrival in their southern African nonbreeding ranges. About 75% of the birds had started before mid-December, i.e., during the main arrival time of the species. The mode of moult scores 1 and 2 was reached on 7 December; the last birds with a score of zero occurred in the first days of January. The mode of moult scores 5 and 6 was reached on 27 February. Thus, the time elapsed between the days when 50% of the population had reached the first and last stages of recorded moult was about 82 days; nine days later 75% had reached this last stage before moult was completed. Thus, individual moult may be estimated to cover about 80-90 days. The main moulting period is between mid-November and mid-March, thus covering about four months. No temporal difference was detected between males and females. A tendency for an advancement of adults compared to young birds was not statistically significant. According to the progress of the moult, sexing of young birds in the field is possible for 50% of the birds towards the end of January and for most birds before mid-February.