Zigzag heron (Zebrilus undulatus) The zigzag heron is an enigmatic, poorly-known little heron of swampy forest. Adults are very dark overall, gray heavily marked with narrow black vermiculations. Juveniles are cinnamon on the face and neck and cinnamon with black vermiculations on the upperparts. This species occurs in areas with slow-moving or standing water adjacent to dense vegetation, including gallery forest, swamp forest and streams, pools and marshes bordering tropical evergreen forest. Here it hunts for small fish and insects from branches low over the water. Birds have a peculiar habit of tail-flicking while hunting. Individuals are most-often detected by scanning the water's edge carefully from a boat or listening for the cooing call near dawn or dusk.