Frolicking whale halts New Zealand fireworks display

A rare visiting whale in Wellington Harbour has won hearts in the New Zealand capital but forced officials to cancel the city's annual fireworks display.

The southern right whale appeared in the harbour on Wednesday and has delighted onlookers as it breaches and blows water spouts a short distance from downtown office buildings.

Whales regularly migrate along the North Island coast near Wellington but do not usually venture into the harbour.

The city's acting mayor Jill Day said the presence of the giant marine mammal meant a fireworks display scheduled for Saturday could not go ahead. She said experts had advised the pyrotechnics, to mark the Maori new year celebration Matariki, could make the whale behave unpredictably.

"We don't want anyone in boats or kayaks on the water, in the dark, to come off second-best if the whale breaches among them," she said.

"We also don't want the whale to be injured in any contact with a vessel." Day said there was strong public support for postponing the fireworks for a week.

"Wellingtonians have fallen in love with this whale, this taonga (treasure), and they've been telling us they don't want anything untoward to happen to it," she said.

"The whale's presence is a true blessing for Matariki." The whale has gone viral on social media, trending on twitter as users share updates on its location using the hashtag #wellingtonwhale.

It was slightly less popular with the operator of the car ferry service operating between the North and South Islands, preventing the ship from berthing as it cavorted near the docks.

After sounding its siren and circling the whale for about 30 minutes, the ferry eventually docked when the sea creature found another place to play.