Productive areas are often associated with structure and changes in the channel. Deep holes, especially those created by scour near weirs or channel bends, hold larger fish. Submerged timber and snags are prime ambush points for Murray cod and golden perch. Areas where smaller channels or drains enter the main channel create confluence zones that attract baitfish and predators. The edges of reed beds and undercut banks provide cover for species like redfin and carp.