Chinese egret is a migratory bird under protection, which propagates in spring at Unmu Islet 14 kilometres southwest from Aedo-dong, Jongju, North Phyongan Province, and flies southward in autumn.

Covering an area of 0.39 square kilometres, the islet is 500 metres wide, 3 990 metres round and 44 metres above the sea.

Here grow such trees as bush clover, weigela, linden, pine, daimyo oak, hornbeam and such plants as bracken and horsetail.

Around May, seabirds like egret, spoonbill, gull and Eurasian oystercatcher nestle and breed on shrub branches, under wormwood or on rocks of the islet and other surrounding islets.

The area is under strict protection as a habitat for seabirds.

Chinese egret at Unmu Islet was designated as a natural monument in January 1980.