[A-CC25] Glaciology in the new normal

[ACC25-P07] Relationship between Haliaeetus pelagicus flights route over the Russian Far East and surface atmospheric conditions

*Kazutoshi Sato¹, Kzutaka Tateyama¹, Saiko Shiraki², Yusuke Murata¹ (1.Kitami Institute of Technology, 2.Tokyo University of Agriculture)

Keywords:Haliaeetus pelagicus, Migratory bird, Sea of Okhotsk

The Haliaeetus pelagicus, which stays over the coastal region of Okhotsk sea of East Hokkaido during winter, is migratory bird. After breeding season over the coastal region of Okhotsk Sea in Russia during summer, they migrate southward in autumn and reach East Asia in early winter. However, no previous study has reported the influence of atmospheric conditions on migration route and timing of Haliaeetus pelagicus. Using reanalysis data and geolocation loggers data, we investigate the relationship between change in surface conditions (e.g. snow cover, sea ice cover, surface temperature) and migration factors (e.g. timing and route) of Haliaeetus pelagicus.
In autumn 2018, two birds stay over Khabarovsk area in Russia. Although departure and arrival areas of two birds are almost same, there are differences in departure date and route of migration of two birds. One bird starts migration toward south in middle of October 2018. After leaving Khabarovsk area, snow accumulation is seen over Khabarovsk area, meaning that this bird avoids snow. In contrast, another one stays over Khabarovsk area even high snow cover. However, this bird starts to migrate when temperature drops below -20 oC. In addition, Haliaeetus pelagicus selects high sea ice cover areas when they migrate northward after winter season. From these results, surface conditions would be an indicator of timing and route of Haliaeetus pelagicus.