Plumbeous Water Redstart

The plumbeous water redstart is a passerine of the Old World flycatcher family, typically 14cm long, with males averaging 22g and females 18.8g. Males are slate blue and females grey, the common name referring to a colour resembling lead. It occurs across South and Southeast Asia and China, typically beside rivers and streams at relatively high elevations; Himalayan records span approximately 2,000–4,100m (Wikipedia, general species account).

To catch flies over rivers, it flies vertically until at least 20 feet above the water, then glides down in a spiral to the same place. This aerial feeding behaviour keeps it closely associated with flowing water, where rocks and banks provide perches between sallies. The Korean vertebrate catalogue used for this guide records the species in South Korea, although the opened sources do not identify a dependable local viewing site (Wikipedia, general species account; Wildlife of Korea occurrence records).