The renowned ornithologist John Gould first described the yellow-billed spoonbill, naming it Platalea flavipes although noting its distinctness from other members of the genus.

He noted the species appeared in great numbers across New South Wales in 1839, particularly in the north between the Hunter and lower Namoi Rivers.

They felt the genetic evidence meant it was equally valid to consider all six to be classified within the genus Platalea or alternatively the two placed in the monotypic genera Platibis and Ajaia respectively.

The yellow-billed spoonbill is carnivorous, catching small animals by sweeping its bill through shallow water and swallowing prey once it is detected.

[6] The yellow-billed spoonbill has a row of small blunt knobs known as papillae which line the margins of the upper and lower mandible of the "spoon".

[6] Prey items recorded at Lake Cowal include freshwater crustaceans such as the common yabby (Cherax destructor); shrimp of the genus Macrobrachium and family Atyidae; insects, particularly aquatic bugs of the families Notonectidae and Corixidae; fish such as mosquitofish (Gambusia affinis) and flathead gudgeon (Philypnodon grandiceps); and occasionally freshwater snails and plant material such as medic burr (Medicago polymorpha).

The nest is a platform constructed of sticks; it has a hollowed centre, and can be located on the branches or fork of a tree, the base of which is often submerged in water.