There is some dispute over the taxonomy of this week's WBW bird - its a Cattle Egret, which some authorities split into two species, while other consider them to be a single species.
I'll go with the taxonomy that is used by eBird which makes these Eastern Cattle Egrets (Bubulcus coromandus)
Originally native to parts of Asia, Africa, and Europe, it has undergone a rapid expansion in its distribution and successfully colonised much of the rest of the world in the last century.