Dunedin's sea lion population could be in for a record breeding season this summer, with 28 breeding age females on the Otago Peninsula.
While not all of them would breed, about 20 pups are predicted this season.
Department of Conservation coastal Otago biodiversity ranger Jim Fyfe said Dunedin was one of the few mainland places where sea lions bred.
"The Otago Peninsula (sea lion population) is descended from Mum who started having pups in 1994. In 2000, we were having two or three pups being born. In 2010, we were having six to eight pups. Last year, we had 18 being born so the numbers are gradually increasing.
"Sea lions, which are endemic to New Zealand, were wiped off the mainland even before Europeans arrived through hunting. They probably disappeared along with the moa, so to see them coming back is really exciting.
"They are quite intelligent and playful animals so we're learning lots about them and they're learning lots about us."
Sea lion mums often chose spots near popular beaches to raise their pups - or in Dunedin's case, a local golf course.
Fyfe said people needed to give them space and keep about 20m away - and keep their dogs away and on a lead.
Restrictions were already in place at Smaills Beach where four to five female sea lions had made their home, and temporary signage would be used to mark parts of other beaches that were lead-only for dogs.
He urged people to be patient and to get in contact with the Department of Conservation if sea lion pups were born in their neighbourhood.
"That way we can just track them and put any protection measures in place to make sure that they can journey (back to the beach) safely."
Sea lion pups would mostly be born in early January, moving onto the beach for swimming lessons a few weeks later.
He advised people who were approached by inquisitive sea lions in the ocean or on land to be boring.
"Don't react by panicking or running away. It takes a bit of nerve sometimes but don't look them in the eye. Look the other way. Pretend you don't care about them at all.
"Keep doing what you're doing. Particularly if you're in a group of people, they'll look for somebody more exciting to play with."
The Department of Conservation has the Lead the Way programme to help people become wildlife-wise dog owners.