A family out dolphin watching in Akaroa Harbour today got more than they bargained for when a pod of killer whales stopped by for a visit.

The group of eight were on a dolphin swimming tour run by the Onuku Farm Hostel, and had already been for a dip with the Hector's dolphins which populate the harbour in summer.

But this morning they had a special visit, crew member Mafi Gehrig said.

"We went out and had a relatively good swim - there were lots of dolphins, which you wouldn't normally expect if there were orcas in the area.


"Then we went for a wee tour around the harbour, to see a bit more than just dolphins -
it's pretty spectacular out here."

Suddenly a group of up to 10 orca "appeared out of nowhere", Gehrig said. Footage of the encounter shows the curious orca nosing up to and diving under the boat, breaching and expelling air.

The five children on the boat were all under 10 and were "absolutely very excited", Gehrig said.

"But everybody was very excited, not just the kids. We're always looking and hoping but it doesn't always happen - we were extremely lucky this morning.

"We know it can happen but it's certainly not a regular occurrence. We might see them two or three times throughout the summer."

The crew believe there were two separate groups of the animals.

"You keep your distance but they come up - they're quite curious animals so they will come and have a look.

"Sometimes they're not so interested and will swim away but they weren't obviously fishing this morning."

The killer whales hung out in the harbour all day, and were sighted close to Akaroa township as late as 8pm tonight.

Guests had been swimming with the dolphins earlier but if they had encountered orca would have left the water, Gehrig said.

"It's not something you would want to risk. You're not allowed to swim with orcas anyway."