The animal, Owha, made its way through the Waitemata Harbour to Westhaven Marina."We kept on monitoring her and monitoring her and she didn't leave," Dr Hupman said.
"The week I left Auckland, she decided to move up to Tutukaka and then to Whangarei, and she is still there."
At NIWA, Dr Hupman, together with Tutukaka's Ingrid Visser from the Orca Research Trust, began collating sightings of leopard seals back to the 1860s and they have come up with 500.
She has also been monitoring a seal in Marlborough, while Dr Visser has been monitoring the recent arrival in Whangarei.
"So what are they doing here?" Dr Hupman asked.
"There's a theory they just get lost in the ice floes and end up going north instead of south. I don't know if we can justify that anymore with what we're seeing now."
- NZME