The white heron or great egret is a cosmopolitan bird and is found worldwide in tropical and temperate regions. Of the four or more subspecies, the range of the largest, Egretta alba modesta, is India, China, Japan, Australia and New Zealand. The birds are venerated in most parts of their Asiatic range, the fragile white plumes which they assume and shed each breeding season have been universally prized for ornament.
Geographically and climatically New Zealand is near the extreme limits of its range. In New Zealand it is a rare bird, and probably always has been. However the species was almost exterminated to satisfy the demand for feathers for women’s hats after its only breeding site on the banks of the Waitangiroto Stream, near Okarito in South Westland was discovered in 1865. By 1941 there were only four nests when it was declared a reserve and patrolled at breeding time. The numbers have now stabilised with a permanent population of around 100 to 120.