"Boiling seas" and high winds are threatening the state of the cargo ship Rena stranded on Astrolabe Reef.

Maritime New Zealand's Ross Henderson says strong winds and rough seas are battering the ship and bad weather is predicted to continue throughout the day.

Almost all of the containers have been removed from the stern of Rena, grounded on Astrolabe Reef. Photo: Maritime New Zealand.

'The vessel is still intact, however, it remains in a fragile state and is at the mercy of the weather.

"The weather in the area comprises strong winds and boiling seas around the port side of the vessel.”

The MetService has issued a gale force wind warning with winds of up to 35 knots offshore causing 'very rough seas.”

Container removal operations were suspended on Wednesday afternoon due to deteriorating weather and Ross says operations will continue to be halted until the weather is sufficiently calm enough to resume operations.

The carne barge SeaTow has abandoned its position next to Rena and is now back in Port.

Maritime New Zealand Salvage Unit manager Arthur Jobard says it will take some time for SeaTow to re-establish position and mooring arrangements next to Rena once the weather is calm enough.

Salvors have lifted 95 containers off Rena, considerably altering the rear profile of the Rena. There are 1185 containers still on board the ship.

Arthur says salvage operations had slowed down, as the location of each container and the condition of its contents affected each removal.

The Go Canopus remains connected to Rena and is continuing to monitor its position.

The National Oiled Wildlife Response Team wildlife manager Helen McConnell says the team will be going to Rabbit Island (Motuotau) tonight to see how the 49 little blue penguins released at Mount Maunganui on Tuesday, November 22 are faring.

'Small numbers of birds will be released as they satisfy release criteria and as habitat is cleaned.

'We are planning to have another public release of penguins at the Leisure Island (Moturiki) site and will advise the public when that is going to happen.”