Coturnix japonica breeds in eastern Asia, including northern Mongolia, Sakhalin Island and the Baikal and Vitim regions of Russia, north-east China, Japan, North Korea and South Korea. Some populations in Japan are resident, but most birds migrate south, wintering in southern China, Laos, Vietnam, Cambodia, Myanmar, Bhutan and north-east India¹. There are also introduced populations in Italy and Hawaii (USA). No reliable population estimate exists, and although the species was previously considered to be fairly common in China¹, declines appear to have occurred in Laos²and Japan^3,4, and there are fears that the species has undergone a significant decline^1,2.