PMC

The main migration route worldwide (The sample location data were referred to published data: Cho & Lee, ; Grond et al., ; Grond et al., ; Risely et al., ; Risely et al., ; Ryu et al., ; Santos et al., . The number represents the research location: 1 = MacKenzie River Delta in Alaska and Canada; 2 = Delaware Bay, USA; 3 = Sirius Passet; North Greenland; 4 = Tagus estuary, Portugal; 5 = Broome, Western Australia; 6 = Victoria, Eastern Australia. The migration route is redrawn according to the content of the URL https://www.sovon.nl/ and https://www.wwt.org.uk/. The black dotted line indicates the East Asia–Australia migration route. The red dotted line indicates the Central Asia–India migration route. The orange dotted line indicates the migration route from West Asia to East Africa. The yellow dotted line indicates the Mediterranean–Black Sea migration route. The green dotted line indicates the migration route in the eastern Atlantic Ocean. The cyan dotted line indicates the migration route of the western Atlantic Ocean. The blue dotted line indicates the Mississippi migration route. The purple dotted line indicates the migration route in the eastern Pacific Ocean)

One dot corresponds to one line studied. The dots are colored according to k-medoids cluster position (see ). Square dots designate lines carrying the T7A:5B and round dots designate lines lacking the 7A:5B. Solid lines designate migration routes supported by our data, while dashed lines designate hypothetical migration routes, which were not confirmed in our study. Thick lines correspond to major migration routes, thin lines to secondary migration routes; 1a —possible migration route of Balkan emmer from Anatolia to the Balkans; 1b —possible migration route of Vol emmer from the Balkans to the Volga region; 4a —possible migration route of Ethiopian emmer from Zagros to Ethiopia via the Arabian trading route and to India by maritime route; 4b —possible migration route of Ethiopian emmer from Zagros through India and Oman to Ethiopia.

Birds were tracked from (a) Pennsylvania (b) Costa Rica. Yellow  =  spring migration, pink, pink  =  fall migration. Orange circle  =  breeding site, blue  =  winter site. Short-dashed lines indicate migration tracks in the second year and long-dashed lines a third year. Dotted lines indicate where migration route was unknown due to poor-quality light data, or geolocator battery failure.

Areas circled in yellow are breeding areas; areas circled in blue are wintering areas (slightly improved based on the range map from IUCN 2017). Black lines represent the migration routes of the black-necked cranes confirmed by satellite tracking or banding. Red lines represent the migration route of black-necked cranes from this study.