Those on the state's east coast are being urged to keep an eye out for an entangled whale calf.
The baby humpback and its mother were spotted near Schouten Island on Tuesday heading south, the juvenile apparently trailing ropes and buoys.
An extensive aerial survey by Marine Conservation Program staff on Wednesday failed to find any sign of the pair.
The public is warned to keep clear of the mammals.
“Our staff are trained in disentanglement response activities, including the use of specialist rescue equipment, to maintain human safety and the welfare of the whale,” said wildlife biologist Sam Thalmann.
“Trying to carry out any rescue without specialist training and equipment is dangerous and should be left to trained wildlife experts.”