There are five little blue penguins and two shags with oil covered feathers in the care of the Wildlife Response Centre at Te Maunga.

They are victims of the oil slick emanating from the 236m container ship, Rena, grounded on the Astrolabe Reef off the coast of Tauranga since 2.20am Wednesday.

This penguin's natural colour is white with a blue back. He is in the care of the Wildlife Response Centre after he became coated in oil leaking from Rena, shipwrecked on the Astrolabe Reef.

They were found on different Bay of Plenty beaches; Papamoa, Little Waihi and on Motiti Island, and are being stabilised before being washed.

There are four teams of wildlife responders based on Motiti Island and another two on the mainland, with a further 10 teams to be deployed today – these teams will be out on beaches today looking for affected animals.

Maritime New Zealand national on scene commander Rob Service says Rena is continuing to leak oil, with it at its worst when the tide is in.

The emergency responders are continuing to use the dispersant Corexit 9500, with it having mixed results in dissipating the 5km long oil slick.

The response team is unable to undertake on-water containment of the slick at this stage as its readily available equipment is inappropriate for the choppy sea conditions at the reef.

The team is waiting for 1250m long offshore booms and three skimmers to arrive from Australia.

The primary goal of the responders is to pump out as much of the 1700 tonnes of fuel oil that is in the ship's tanks as is possible.

This is a task for a vessel en route from Auckland. It is expected to arrive on Monday.

This does not give the responders much time, however, as 20 knot northerly winds are expected on Tuesday.

These will generate rough seas and may make a pumping operation impossible.

Rough seas also pose a danger to Rena as they will likely move the ship around, causing more damage, which in turn increases the risks of leaking.

Rob Service says the leaks are intermittent and it is hard to gauge how much oil has leaked into the sea, although there is 100 tonnes unaccounted for.

He says criticism that the fuel transfer is taking too long is uninformed.

'This is not like removing fuel from a dinghy. It's not even like removing fuel from a 30 metre fishing vessel. We're talking about an extensively damaged 236m cargo vessel.

'This is a challenging and complex operation.”

The government is becoming more involved in the incident with Transport Minister Steven Joyce coming to Tauranga to inspect the wreck on Friday.

At a press conference he said in time it was likely oil would wash up on beaches in the region.

'The situation with the oil is going to get worse before it gets better.”

The New Zealand Defence Force is mobilising with the HMNZS Endeavour on standby.

Prime Minister John Key is also heading for Tauranga on Sunday to inspect the wreck, slick and emergency response command centre.

The salvage company Svitzer has 82 cubic metres of specialist salvage equipment being prepared to deploy from Australia.

The salvage team of 15 would grow to around 25 over the weekend. Svitzer's first priority is to get the fuel off the vessel.