"The passengers were over the moon," MV Monarch skipper Rachel Heseltine told the Otago Daily Times yesterday afternoon.
The vessel was contacted by a Karitane resident and another skipper to say the pod was spotted off the Otago coast, and "we went looking for them", she said.
The crew and the 16 tourists spotted the distinctive vapour spouts coming from the pod, which was 3km from the entrance to Otago Harbour.
Arriving at the area shortly after 2pm, they spotted a large male orca, believed to be between 7m and 9m long, a female orca, and possibly a smaller calf estimated to be about 5m long.
Mrs Heseltine said the size of the whales was impressive when compared with the 16m-long vessel.
In her almost seven years with Monarch Wildlife Cruises and Tours, she had seen orcas just five times, with the most recent sighting last year.
"They are usually travelling south, so what was unusual about this lot was that they were hanging around the same spot," Mrs Heseltine said.
Department of Conservation coastal Otago area ranger Jim Fyfe said in the past five years sightings of orcas had become more common off the Otago coast when compared with the previous five years.
While orcas were known to feed on stingrays in the warmer northern waters, it was likely they fed on fish and small mammals in the south, he said.
Boat users were advised when coming across orcas to keep a distance of 50m away, he said.
In addition to the Dunedin sighting, orcas were also spotted in Wellington Harbour yesterday.
