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Bird ringing was established more than a century ago to gather information on bird movements. Since then, ornithologists have systematically collected huge databases of records of birds ringed and subsequently re-encountered, but, to date, there have been few quantitative attempts to identify migratory routes from ringing data. Here, we develop a novel, quantitative method for describing migration routes using ringing data and we applied it to a dataset of 72,827 ring recoveries of the Barn Swallow (Hirundo rustica) through western and central Europe from the EURING and SAFRING databanks spanning 1908-2011. We considered movements of 332 individuals during spring migration and 1509 during autumn migration. The results indicate that, in spring, Barn Swallows enter western Europe through Gibraltar or by crossing the Mediterranean Sea through the Balearic Islands, Sardinia, and the Italian peninsula. They then spread over a wide front. In northern France, Belgium and the Netherlands routes diverge, pointing toward either the British Isles or Denmark and Scandinavia. Autumn migration routes are similar to those in spring. The general migration pattern that emerged from the analyses was consistent with previous descriptions of migratory movements of this well-known species. However, this analysis also revealed some previously undocumented migration patterns. For instance, in spring, some migrants moved from the Balearic Islands to Corsica and Italy, thus making a rather long eastward crossing of the Mediterranean Sea. In autumn, some migrants moved from the Balkan Peninsula westwards toward Italy. Analyses restricted to recoveries within the same spring or the same autumn and to birds found dead showed similar patterns. Our procedure was, therefore, able to identify migration patterns over a large geographical area, and may be extended to those species for which large datasets of ring recoveries or sight-resight data are available. [ABSTRACT FROM AUTHOR]

Between 2006 and 2008, 14 Montagu's Harriers ( Circus pygargus) were tagged with satellite transmitters at their breeding grounds in NE Spain, recording a total of 18 autumn and 10 spring journeys. In both autumn and spring migrations, harriers migrated between Europe and West Africa along a relatively narrow corridor between the coast of Morocco and Western Sahara and the western border of Algeria. Birds tended to follow a slightly more westerly track during spring migration compared to autumn migration. Harriers started autumn migration in late August-early September, arriving at their wintering grounds in early-mid-September, after travelling between 8 and 25 days, and covering a mean of 187 km a day. Spring migration started in mid-March, with birds arriving at the breeding grounds in mid-April after covering a mean of 114 km a day. On average, spring migration lasted longer, with birds covering longer distances than during autumn migration, and distances travelled in a day tended to be shorter. Significant differences in the routes followed by harriers were observed among seasons and individuals, with the same individuals following different routes in different years. Wintering areas were located in northern Senegal and the southern border of Mauritania with Mali, with some birds breeding in the same colony in Europe separated more than 1,200 km during the wintering season. Birds showed a relatively high fidelity to their wintering areas. Several birds moved from one area to another during the wintering period, which resulted in larger wintering areas, whereas others remained in the same area during the whole wintering season. Zwischen 2006 und 2008 wurden 14 Wiesenweihen ( Circus pygargus) in ihren Brutgebieten in Nordostspanien mit Satellitensendern versehen und insgesamt 18 Herbst- und zehn Frühjahrszugwege aufgezeichnet. Sowohl auf dem Herbst- als auch auf dem Frühjahrszug zogen die Weihen zwischen Europa und Westafrika in einem relativ engen Korridor zwischen der Küste Marokkos und der westlichen Sahara und der Westgrenze von Algerien. Die Vögel tendierten dazu, auf dem Frühjahrszug einem etwas westlicheren Kurs verglichen mit dem Herbstzug zu folgen. Die Weihen begannen mit dem Herbstzug Ende August bis Anfang September und kamen in ihren Überwinterungsgebieten Anfang bis Mitte September an, nachdem sie zwischen acht und 25 Tage geflogen waren und im Mittel 187 km pro Tag zurückgelegt hatten. Der Frühjahrszug setzte Mitte März ein, und die Vögel trafen Mitte April in ihren Brutgebieten ein, wobei sie im Mittel 114 km pro Tag flogen. Der Frühjahrszug dauerte im Durchschnitt länger als der Herbstzug, die Vögel legten größere Entfernungen zurück, und die an einem Tag zurückgelegte Entfernung war tendenziell kürzer. Zwischen verschiedenen Saisons und Individuen wurden signifikante Unterschiede in den von den Weihen geflogenen Routen beobachtet, und dieselben Tiere nutzten verschiedene Routen in verschiedenen Jahren. Die Überwinterungsgebiete lagen in Nordsenegal und an der Südgrenze Mauretaniens zu Mali. Einige Vögel, die in Europa in derselben Kolonie brüteten, überwinterten mehr als 1,200 km voneinander entfernt. Die Weihen zeigten eine relativ ausgeprägte Treue zu ihren Überwinterungsgebieten. Einige Vögel zogen während der Überwinterungsperiode von einem Gebiet zu einem anderen, was in insgesamt größeren Überwinterungsgebieten resultierte, wohingegen andere während der gesamten Wintersaison im selben Gebiet blieben. [ABSTRACT FROM AUTHOR]

The Kyrgyz population of the bar-headed goose Anser indicus has declined dramatically during the past decades. Human persecution during migration and habitat loss at stopover and wintering sites are commonly regarded as most serious threats. However, little is known about seasonal movements, migration routes, and wintering sites of the bar-headed geese from Kyrgyzstan, which represent the westernmost geographical population of the species. As part of a conservation project, which also included reinforcement of the wild population by the release of hand-reared juveniles, in late summer of 1998, five bar-headed geese, three wild adults and two hand-reared goslings, were fitted with sun-powered satellite transmitters in order to track their movements from Lake Son Kul and Lake Chatyr Kul in Kyrgyzstan. The five individuals contributed very unevenly to the more than 5,000 signals in total that were received from the French ARGOS system: one failed after 8 weeks, while another one was tracked for more than 2 years. The four geese contributing to this study followed three completely different migration routes leading to their wintering areas in Pakistan, India and Uzbekistan, while stopover areas were situated in southern Tajikistan and in western Tibet. Both in autumn and spring the adult birds migrated distances of 1,280–1,550 km in two steps, with stopover periods of 32–46 days (autumn) and 16–23 days (spring). Flight speeds of up to 680 km per actual migration day were recorded regularly, even during crossings of very high summits. A hand-reared juvenile flew non-stop for 790 km to southern Uzbekistan and even visited southernmost Turkmenistan, where the species is very rarely seen. The timing of migration varied considerably between individuals but also for the same individual between years. We compare our tracking results with previous findings (field observations, ring recoveries, and satellite tracking results) and discuss them with respect to migration over high-mountain habitats and a general migration strategy of the species. [ABSTRACT FROM AUTHOR]