Over November and December 2022 Banyule Swamp has been covered with a mat of the aquatic plant Red Water-milfoil (Myriophyllum verrucosum). This plant has underwater stems with whorls of feathery green leaves (photo 1) and emergent stems with red leaves (photo 2). The dense cover of Water-Milfoil has been appreciated by Grebes and Coots which have piled it up into mounds to make nests that sit just above the waterline. See Vicflora for a full description of Red Water-milfoil.
Photo 1 - Underwater stems with green leaves.
Photo 2 - Above-water stems and red leaves.