TAIPEI (Taiwan News) — The sighting of a pied harrier near the Tsengwen River in Tainan attracted bird enthusiasts hoping to catch a rare glimpse of the black and white bird of prey.

According to the Wild Bird Society of Tainan, the pied harrier is widely distributed across Asia. It typically breeds in northeast Asia and spends summer and winter in south and southeast Asia, per CNA.

The pied harrier often transits through Taiwan, where it occasionally chooses to spend winter. The most recent sightings have been juvenile males, though appearances only happen every few years. 

The male pied harrier is mostly white except for the head and wingtips. According to the author of "Wild Birds of Taiwan," Liao Ben-xing (廖本興), the recently observed pied harrier in Taiwan is three years old and still molting. Liao said the bird's plumage will become even more impressive in adulthood.

According to reports by domestic birders, the pied harrier appeared at the mouth of Yunlin’s Zhuoshui River in May this year and flew to Tainan’s Tsengwen River in mid-August. It is the first time a pied harrier has stayed in Taiwan from spring to autumn.

According to the author of “A Field Guide to the Raptors of Taiwan,” Lin Wen-hung (林文宏), a stable breeding population of pied harriers exists on Luzon Island in the Philippines. Lin said the pied harrier could have come from Luzon Island if it did not complete its northward migration.

The Wild Bird Society of Tainan told bird watchers to pay attention to safety when venturing into the Tsengwen River. It said to avoid blocking traffic, parking on farmland, and disturbing farmers.