Whooper swan 'Yeoreum' completes round trip between Nakdong estuary and Russia

A whooper swan named "Yeoreum," hatched at a zoo and trained to adapt to the wild at an alternative waterbird habitat on Busan's Eulsukdo, has completed a full migratory round trip — flying to Russia last year to breed, returning to Busan for the winter, and heading north to Russia again this spring.

The Nakdong Estuary Eco Center under the Nakdong River Management Authority announced the findings Tuesday, calling it the first confirmed case in South Korea of a captive-bred whooper swan independently completing an international migratory route and returning to its home site. The whooper swan is listed as an endangered wild species class II and designated a natural monument.

Yeoreum hatched at Everland in Yongin in May 2023 and was transferred to the waterbird alternative habitat at Eulsukdo that October for systematic wild-adaptation training. In the spring of 2025, GPS data from a tracker attached to the bird confirmed it had flown 2,300 kilometers through Ulsan and North Korea to Russia's Primorsky Krai, drawing wide attention from the scientific community.

What followed was even more remarkable. After spending the breeding season in Russia, Yeoreum flew south as autumn cold set in last October, wintering near Yeongdeok and Gyeongsan in North Gyeongsang Province. In March, it returned to the very waterbird habitat at Eulsukdo where it had been raised.

Yeoreum spent more than a month foraging and resting at and around the Eulsukdo habitat before departing for Russia again in April — mirroring its journey of a year earlier. Recent tracking data show the swan has since settled in Primorsky Krai near Vladivostok.

Bird experts say the achievement goes beyond the mere survival of a captive-bred individual, calling it an ecological milestone that demonstrates the full recovery of complex migratory instincts in a hand-raised animal. Seo Jin-won, director of the city's Nakdong Estuary Eco Center, said Yeoreum's return to Busan proves "just how precious and safe a home the Nakdong estuary is for migratory birds."