Little penguins make new friends

Twirl is shy, Velma is dominant. And now they're part of one big, happy little penguin family.

The pair waddled into their new home at Sydney's at Manly Sea Life Sanctuary on Wednesday after spending three weeks in quarantine.

It was quite a stint, given they were only making the short journey from Taronga Zoo lower down the harbour.

Little penguins are friendly, social animals and Sea Life veterinary nurse Marina Tsamoulos says the group is "getting along beautifully".

The younger and smaller Twirl is known for being shy while Velma is a dominant and "very, very curious" individual.

Little penguins, the smallest of the species, grow to about 30-35cm in height and weigh about one kilogram.

The new arrivals are part of a national breeding program and have been brought to Manly to balance out the colony's gender ratio.

It's hoped they'll boost the chances of the "relatively new" colony breeding this season.

"We've only had them for just under two years," Ms Tsamoulos told AAP.

"We didn't expect to have any breeding immediately, so this year they're just gearing up for their breeding season again and to start nesting."

Male little penguins begin digging burrows and attracting mates between June and August and most couples remain breeding partners for life.

An endangered wild population lives in Sydney's north harbour.