"This is the time of year when pups get old enough to move, and sea lions start to move them back to geographically enclosed bodies of water so the pups can play while the mothers go out to feed in the open water."
Fyfe said the journey towards the coast often involved crossing roads, and he urged drivers to take extra care while driving on coastal routes.
An 8-year-old sea lion and her 1-month-old pup were hit by a car while crossing Kaka Point Rd last week, killing them both.
He said it was a tragic loss of a sea lion well-known to the local Doc office.
"That is the dangerous journey that I'm worried about at the moment.
"Like Kaka Point, around Dunedin we have lots of coastal roads and when these pups and their mothers are on the move, we don't know where they're going to turn up.
"They really do share habitat that humans use as well.
"You name a human activity on the coast and a sea lion could turn up in the middle of it.
"So we really want to appeal to motorists on coastal roads to be really wary and think about coastal wildlife, and sea lions in particular, for the next two months.''
Signs warning people of seals and sea lions have been installed near Smaills Beach, and also on roads near Hoopers and Papanui Inlets.