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Most migratory birds return every year to the same breeding sites and some species show a similarly high fidelity to wintering grounds as well. Fidelity to stopover sites during migration has been much less studied and is usually found to be lower. Here, we investigate site fidelity and distance to previously visited sites throughout the annual cycle in the common cuckoo, a nocturnal trans‐Saharan migrant, based on satellite‐tracking data from repeated annual migrations of thirteen adult males. All birds (100%) returned to the same breeding grounds, with a median shortest distance of only 1 km from the locations in previous year. This was in strong contrast to a much lower and much less precise site fidelity at non‐breeding sites during the annual cycle: In only 18% of the possible cases in all non‐breeding regions combined, did the cuckoos return to within 50 km of a previously visited non‐breeding site, with no significant differences among the main staging regions (Europe in autumn, Sahel in autumn, wintering in Central Africa, West Africa in spring, Europe in spring). The shortest distance to a previously visited non‐breeding site differed among the staging regions with median shortest distances for the longest stopovers of 131 km [2;1223] (median [min;max]) in Europe, 207 km [1;2222] in Sahel in autumn and 110 km [0;628] in Central Africa. The distance to a previously visited staging site decreased with the time spent at the stopover in a previous year. Understanding the drivers of recurrence and site selection in migratory birds are important for guiding conservation efforts in this group but further studies are needed to establish whether the patterns observed in cuckoos are general among terrestrial migrants with continuous distribution of habitat. [ABSTRACT FROM AUTHOR]

We tracked departures of European Robins Erithacus rubecula stopping over during spring migration at Skagen, Denmark, and facing a sea crossing of more than 50 km. The Robins stopped over on average for 3.8 days (range 1–14 days, n = 15) with departure days being slightly warmer than stopover days (1.5°C warmer, P = 0.003). Departures were concentrated in the evening, on average during astronomical twilight, and toward the northeast (µ = 33.3°, r = 0.499, P = 0.021). The mean northeasterly departure direction is close to the standard migration direction. Most birds probably crossed the sea to Sweden and we observed no obvious reversed departure directions. [ABSTRACT FROM AUTHOR]

The regular fluctuation of resources across the Globe guides movements of migratory animals. To ensure sufficient reproductive output and maintain viable population sizes, migratory animals should match arrival at breeding areas with local peaks in resource availability. It is generally assumed that breeding phenology dictates the timing of the annual cycle, but this is poorly studied. Here, we use light‐level geolocator tracking data to compare the annual spatiotemporal migration patterns of a long‐distance migratory songbird, the red‐backed shrike, Lanius collurio, breeding at widely different latitudes within Europe. We find that populations use remarkably similar migration routes and are highly synchronized in time. Additional tracks from populations breeding at the edges of the European range support these similar migration patterns. When comparing timing of breeding and vegetation phenology, as a measure of resource availability across populations, we find that arrival and timing of breeding corresponds to the peak in vegetation greenness at northern latitudes. At lower latitudes birds arrive simultaneously with the more northerly breeding populations, but after the local greenness peak, suggesting that breeding area phenology does not determine the migratory schedule. Rather, timing of migration in red‐backed shrikes may be constrained by events in other parts of the annual cycle. [ABSTRACT FROM AUTHOR]

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The article discusses the effect of climate in the migratory behaviour of migratory birds. The study, conducted in various places in the world, showed that environmental conditions in the wintering areas, as well as the route towards breeding areas, have an effect on the timing of migration of the birds. It is concluded that the varying phenological patterns at different latitudes and between the routes of migratory birds are due to phenotypic responses to spatial variability in conditions en route.