It may not have reached the heights of the Rena, but wildlife experts are expecting to see more oiled penguins as the fall-out from Mobil's oil spill in Tauranga Harbour continues.

Overnight, four oiled penguins were spotted by the Mauao Area Wildlife Trust conducting searches of the Mauao and Leisure Island penguin roosts.

Clean-up efforts following Monday's oil spill.

'Three of them just had a few speckles, so we just left them alone,” says Mauao Area Wildlife Trust director Julia Graham.

'The other one was quite bad with oil over its chest, but unfortunately it took off to the ocean so we couldn't get to it.”

The searches come after a corroded Mobil pipeline was blamed for the heavy oil spill that leaked into Tauranga Harbour on Monday.

It is still not known how much oil was leaked, with the black mess found as far away as Maungatapu.

Julia says it was decided that the three penguins showing small specks should be left alone, as taking them in for treatment would prove too stressful.

'You have to weigh up the amount of stress that you put them through to take them in,” she explains.

'If it's just a tiny bit of oil on the surface and not stuck in their feathers, it will hopefully either wash off in the ocean or get preened off.”

If any penguins are deemed to be too heavily coated they will be taken to ARRC Wildlife Trust for an assessment. To be fully cleaned, a penguin must be held for six weeks to regain their waterproof abilities.

'We are treating it like the Rena,” adds Julia. 'We have a certain degree of oiling where we will bring them in, and if it's a light degree we'll leave them if it won't affect them that much.”

The 20-strong group will continue to conduct evening searches over the next fortnight, as it is likely any oiled penguins will pop up at dusk.

And unfortunately, Julia is expecting more penguins to be affected.

'They pulled seven tonnes of oil debris out of the harbour yesterday,” she says, 'and the penguins love the harbour. So I'm definitely expecting to see more.

'There is definitely a few penguins getting oiled, but nothing like the Rena where some were 100 per cent covered.”

'At this time of the year it's a bit cold, so even a few specks of oil can affect their waterproofing and make them quite hypothermic and dangerous for them.”

The group also located large clumps of oiled seagrass washing up around the sandy bay area, accompanied by a strong oil smell. This has since been washed away with the tide.

Anyone willing to help with searches around Mauao and Moturiki Island are asked to meet at 5.45pm in front of the Mount Maunganui Surf Club. A torch is required.

For more information, contact Julia on: 07 544 5190.