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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.

The degree to which individuals migrate among particular breeding, migration, and wintering sites can have important implications for prioritizing conservation efforts. Four subspecies of Dunlin (Calidris alpina) migrate along the East Asian-Australasian Flyway. Each subspecies has a distinct and well-defined breeding range, but their migration and winter ranges are poorly defined or unknown. We assessed the migratory connectivity of 3 of these subspecies by evaluating a dataset that encompasses 57 yr (1960-2017), and comprises more than 28,000 Dunlin banding records and 818 observations (71 recaptures and 747 band resightings). We present some of the first evidence that subspecific segregation likely occurs, with arcticola Dunlin wintering in areas of Japan, and other arcticola, actites, and sakhalina Dunlin wintering in areas of the Yellow and China seas. Observations indicate that whether an arcticola Dunlin winters in Japan or the Yellow and China seas is independent of their breeding location, sex, or age. Furthermore, observations indicate that ≥83% of arcticola Dunlin exhibit interannual site fidelity to specific wintering sites. This suggests that the degradation of specific wetland areas may negatively affect particular individuals of a particular subspecies (or combination of subspecies), and, if widespread, could result in population declines. Given the possible biases inherent in analyzing band recovery data, we recommend additional flyway-wide collaboration and the use of lightweight tracking devices and morphological and genetic assignment techniques to better quantify subspecies' migratory movements and nonbreeding distributions. This information, when combined, will enable effective conservation efforts for this species across the East Asian-Australasian Flyway. LAY SUMMARY The East Asian-Australasian Flyway has more threatened and near-Threatened migratory waterbird species than any other flyway in the world; however, developing flyway conservation plans has been challenging, in part due to limited information regarding population-specific migration patterns. Four subspecies of Dunlin migrate and winter along the East Asian-Australasian Flyway. Each has a well-defined breeding range; their migration and winter ranges are poorly defined or unknown. We assessed the migratory connectivity of 3 subspecies using data from 57 yr (1960-2017), which comprises more than 28,000 Dunlin banding records, 71 recaptures, and 747 band resightings. Subspecific segregation likely occurs, with arcticola Dunlin wintering in Japan, and other arcticola, actites, and sakhalina Dunlin wintering in the Yellow and China seas. It is likely that ≥83% of arcticola Dunlin exhibit interannual site fidelity to specific wintering sites. Our findings suggest that degradation of specific wetland areas may negatively affect particular individuals of a particular subspecies (or combination of subspecies) and could result in population declines.

The article presents the results of the Steppe Eagle (Aquila nipalensis) monitoring in the Republic of Kalmykia in 2013–2015. For 2011–2015 the population of Steppe Eagle in Kalmykia decreased by 23% and is 404–720, at average 527 breeding pairs. In 2015 the average density of occupied breeding territories on the main part of the Steppe Eagle breeding ground in Kalmykia was about 1.7 per 100 km2, in the breeding ground of the high density of species, on Ergeninskaya hill, where about 20% of Kalmyk Steppe Eagle population is nesting – 7,9/100 km2. In 2015 the density of successful pairs was1.3 (0.98–1.7) pairs/100 km2 on the main areas, on Ergeninskaya hill – 7.1 (4.9 – 10.4) pairs/100 km2, observed breeding success in 2015 is 1.58±1.11 nestlings per occupied breeding territory. The rejuvenation of the population has been noted: among the birds on the breeding territories the proportion of partners younger than 5 years has increased by 3 times in 2 years – from 1.75 to 5.26%. The main threats to the Steppe Eagle in the Republic of Kalmykia are death on power lines, steppe fires, destruction of nests by cattle or killing of nestlings by herding dogs, disturbance factor in grazing. It is likely that the decline of eagles’ population is due to increasing of negative factors on the migration routes and wintering grounds.

В Лукояновском районе Нижегородской области 22 апреля 2014 г. было найдено гнездо ястребиной совы, которое располагалось на вершине слома ствола сухой берёзы на высоте 12–14 м.