Tanya and James Younan had taken their dog for a walk when they spotted the penguin about 2.45pm.

Mrs Younan said she was down at the harbour almost daily but had never seen a penguin there before.

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While the penguin did not appear to be in distress, she said she and her husband were concerned because of the amount of rubbish in the water and fishers.

Mrs Younan called WIRES, who said they would pass on news of the sighting to the relevant organisation.

While the penguin in the harbour was a new sighting for Mrs Younan, some people on social media reported having seen them there in the past.

Rescue and rehabilitation coordinator for the South Coast branch of Australian Seabird Rescue Lisa Hood said it was not unusual to see Little Penguins in Wollongong.

She said there was a colony on an island off Port Kembla where the penguins bred.

"It is not overly unusual to see a penguin go into the harbour, they go into Kiama harbour all the time," Ms Hood said.

She noted the penguin was displaying normal behaviour and after speaking with Mrs Younan she did not have any concerns about its welfare.

"[Mrs Younan] told me it took one final dive and didn't resurface which is good. It wasn't hanging around the harbour when she left," she said.

Ms Hood said penguins had likely had a rough couple of weeks with the rain and big waves, burrows might have flooded or it could have been following fish into the harbour.

Ms Hood stressed the importance of people not touching penguins if they saw them in the harbour, in the water or on beaches.

"If you see one, don't touch it, call us and keep your dogs away from it. Observe it from a distance, and we will send someone out immediately," she said.

Australian Seabird and Turtle Rescue South Coast branch can be contacted on 0431 282 238.

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