Night Heron, or Qua bird

Seen by day, these chunky herons seem dull and lethargic, with groups sitting hunched and motionless in trees near water. Black-crowned Night Heron become more active at dusk, flying out to foraging sites, calling 'wok' as they pass high overhead in the darkness. Some studies suggest Black-crowned Night Heron feed at night because they are dominated by other herons and egrets by day. A cosmopolitan species, nesting on every continent except Australia and Antarctica.