Leopard seals regularly make winter forays to the Otago coast between June and October but it is the first time they have been confirmed in such numbers.
Department of Conservation marine ranger Jim Fyfe said because of the time of the sightings this year, Doc had been able to determine at least four of the seals were in Otago, with sightings at Oamaru, Moeraki, Aramoana and Brighton.
The reason for the increased numbers was not known, nor was the reason for their visits, although other subantarctic species spend their summers in the food-rich waters of the Antarctic before moving north to warmer waters so it was thought the leopard seals were doing the same.
They spent most of their time at sea but did like to spend time on land, particularly when moulting.
Doc advised the public to keep their distance from the seals.
Although they were not as fast-moving as sea lions, they did have much bigger teeth and they were capable of doing a lot of damage, particularly to dogs, Mr Fyfe said.
The seals were long and slender.
They could be identified by their lack of external ears and their much shorter fore flippers, which meant they "caterpillared" along the beach.
Often, they looked as if they were ill, with runny noses and abscesses, but had a remarkable ability to recover, he said.
