Black-crowned Night Heron - Nycticorax nycticorax
The Black-crowned Night Heron (Nycticorax nycticorax), commonly abbreviated to just Night Heron in Eurasia, is a medium-sized heron found throughout a large part of the world, except in the coldest regions and Australasia (where replaced by the closely related Rufous Night Heron, with which it has hybridized in the area of contact).
Immature birds have dull grey-brown plumage on their heads, wings, and backs, with numerous pale spots. Their underparts are paler and streaked with brown. The young birds have orange eyes and duller yellowish-green legs. They are very noisy birds in their nesting colonies, with calls that are commonly transcribed as quok or woc, woc.