Solar PV Commercial CEO Jem Rowe, whose staff spotted the whale on Monday, said extensive searches from the air had failed to relocate the whale again.

"National Parks lost sight of it at Grass Hopper Island near Durras," he said. 

"At about 6pm last night (Monday), Ian (a staff member) flew up and down the coast from Moruya Airport to Batemans Bay and couldn't see the whale.

"At 7.30am today (Tuesday) the boys left Moruya Airport and zig zagged out to see and didn’t see it. 

"It is not north of Moruya, it has gone south."

6.15: Bad weather forced a rescue crew to abandon hopes of helping a young whale caught in a net off the Eurobodalla coast on Monday afternoon, but the team hopes to try again on Tuesday.

National Parks and Wildlife Service (NPWS) whale specialist Lawrence Orel said a severe weather warning forced a team to abandon plans to travel by boat to where the whale was last sighted, north of Batemans Bay.

Mr Orel said the stricken calf was a humpback, travelling with its mother south to Antarctica after the winter breeding season in Queensland.

He estimated the calf was born this season.

Mr Orel said safety was a major factor for the rescue crew, which he hoped would leave Batemans Bay on Tuesday morning, if conditions eased.

“There are a range of factors that must be considered in any rescue effort, including the behaviour of the entangled animal,” Mr Orel said.

The urge of the mother to protect its calf was also a factor in planning any rescue attempt.

“In this case, we have a mother whom, as most would appreciate, is the calf’s only source of protection and food.

“They rely entirely on their mothers for survival.

“The crews must consider also the weather and sea conditions. 

“While the NPWS is working in the interests of the animal, the safety of everyone involved in any rescue is paramount.”

5.50pm: The young whale sighted dragging a net in open sea off the Eurobodalla coastline is believed to be heading south with its mother.

A severe weather warning was issued for the area this afternoon, hampering efforts to mount a rescue effort.

1.20pm: Rescuers have urged boaters to avoid the Depot Beach area to prevent further distress to the whale calf and mother.

An Office of Environment and Heritage spokeswoman said boaters must respect exclusion zones but hoped boaters would avoid the area entirely.

She said a National Parks and Wildlife Service crew was investigating its options to attempt to help the calf.

“We are looking at options for rescue,” she said.

In normal circumstances, boaters are asked to remain within 100m to 300m of migrating whales.

​12.55pm: A whale calf is reportedly in distress caught in a net off Depot Beach.

Staff from Solar PV Commercial spotted the calf and its mother shortly after noon on Monday from a helicopter it was using to transport staff from a local project.

Company CEO Jem Rowe said the calf was about 150m offshore Depot Beach and “fully tangled” in what looked like a fishing or shark net.

Mr Rowe said the calf clearly looked like it was in distress.

He said he alerted marine mammal rescue organisation ORRCA as well as National Parks and Wildlife Service and it is understood rescue teams are on their way.

Mr Rowe said his helicopter crew was waiting to assist in any way it could.