Most sea leopard seals stay within the pack ice but some adventurous young animals move north in winter to subantarctic islands or the coasts of southern continents.
The Department of Conservation expects the Ruakaka visitor will find Northland a little too hot for comfort and eventually slip away to colder climes.
Meanwhile, other furry, floppy creatures of the sea sometimes seen lying about in spots populated by people are usually juveniles taking a break from storms at sea.
Seals - often seen on coastal or harbourside banks, walls, jetties or other structures in winter - should be left alone, DoC says. It often fields calls from the public concerned about the welfare of New Zealand fur seals which can look scrawny and have weepy eyes, but that is their natural appearance.
A DoC spokesman said seals are wild animals and will defend themselves if they feel threatened. They can carry infectious diseases and can cause serious injuries.
When a seal is on or near a beach or in-harbour, people should not go within 20 metres of it, must keep dogs on a leash and keep children at a safe distance.
If a seal is obviously injured, endangered or poses a danger, call the 24-hour DOCHOTLINE (0800 362 468).
