A small heron that hides in reeds and freezes with its neck stretched when it senses danger.
It is Japan's smallest heron. Males have black heads, while females have stripes from the neck to the chest.
It often stays among reeds and other dense plants and begins calling around evening. When approached, it may stretch its neck upward and remain still.
The female builds pads of stalks and fronds in waterside shrubs or marsh plants, often with a bent-leaf canopy. Clutches contain three to seven eggs, usually four to six; incubation lasts 17–20 days.
The upperwings have pale sandy-buff patches contrasting with black feathers, and the tail is black. White underwing patches contrast with grey flight-feather undersides.
Juveniles lack the adult male’s dark crown and have dark streaks on the head, back, and underparts. The upper bill is dark brown, the lower bill yellow, and the eyes yellow.
An extinction-risk assessment has not been added yet.