A five-and-a-half metre recreational fishing vessel, with six people on board, activated an emergency safety beacon just after 3pm when the boat started taking on water, about 17 nautical miles (31 kilometres) south-west of Cape Nelson. 

The Australian Maritime Safety Authority (AMSA) rescue co-ordination centre alerted the Coast Guard and sent a fixed wing aircraft and the HEMS 4 rescue helicopter to the scene. 

Portland Coast Guard flotilla commander Michael Krause said the Kota Lukis cargo vessel was also diverted, but was stood down once the Coast Guard arrived.  

"The HEMS 4 chopper lifted one passenger off the vessel before the coast guard boat arrived," he said.

"The other passengers were transferred to the coast guard vessel." 

He said the fishing boat is being brought back under tow, and was expected in port later tonight.

Mr Krause said conditions weren't very favourable early in the rescue. 

"The swell was up between three and four metres early on," he said. 

"Towards the end the wind had dropped and so did the swell to about two and a half metres." 

EARLIER: A RESCUE is underway about 31 kilometres off the coast of Portland.

Portland Coast Guard flotilla commander Michael Krause said a distress call came in late Monday afternoon. 

He said a five-metre recreational vessel with six people on board was taking on water, about 31 kilometres off the coast. 

The Portland Coast Guard boat and the HEMS 4 rescue helicopter are on scene. 

The Australian Maritime Saftey Authority (AMSAR) said the vessel activated a beacon 17 nautical miles (31 Kilometres) south west of Portland. 

An AMSA spokeswoman said a rescue aircraft at the scene has reported that the vessel is still afloat.