Smaills Beach is likely to be closed to dogs and vehicles from today, until a sea lion and its pup find a new home.
Department of Conservation biodiversity ranger Jim Fyfe said the 3-week-old pup, born on Tomahawk Beach, and its mother had moved ''just around the corner'' to Smaills Beach.
A temporary cordon around the eastern end of Tomahawk Beach would be lifted, and a ban placed on Smaills Beach, he said.
The pup was the first born in Dunedin this season and was first seen at the water's edge on Smaills Beach with its mother last Saturday.
Mr Fyfe said it seemed the pup and its mother had gone for a swim and subsequently settled in the sand dunes on Smaills Beach, where they were again seen on Wednesday evening.
He would contact the Dunedin City Council dog control unit to monitor the new cordon.
Signs would be placed at the beach, warning dog owners not to enter the area with their pets.
Vehicles would also be prohibited on the beach while the sea lion and its pup were there, Mr Fyfe said.
Under the Marine Mammals Protection Act 1978, no vehicles are allowed within 50m of marine mammals.
Mr Fyfe said Smaills Beach was a haven for other wildlife, including yellow-eyed penguins, and he urged people to be mindful of that when thinking about walking dogs or driving vehicles nearby.
He said the pup was looking healthy.
Doc staff were unable to identify the mother, believed to be one of two known young females in the area.
Last year, five sea lion pups were born on Dunedin beaches, two of which died of disease.
Another half-dozen pups were expected to be born in the area this season, Mr Fyfe said.
