A rare humpback whale has been spotted in Akaroa, this year's first sighting of the enormous creatures by a local cruising company.

Passengers and tourists aboard Black Cat Cruises' Akaroa Harbour Nature Cruise saw the whale about 1pm yesterday outside the Akaroa headlands.

Skipper Chris Jenkins guided the Swimming with Dolphins vessel to the headlands so guests could watch the large humpback whale from a safe distance.

"For the last few years, we haven't run our dolphin swim experience in the winter months so we would often miss humpback whale sightings," he said.


"We are so happy to have experienced this rare sighting and look forward to many more as they start to migrate north for winter."

Black Cat staffer Natasha Lombart described the encounter as "simply amazing".

"We watched in awe as this beautiful whale cruised past. We couldn't predict his age but we could tell from his distinct markings that he was not a juvenile humpback whale," she said.

"We also had the most dolphins I've ever seen on a swim experience in four years. This coupled with the humpback whale and an albatross sighting on a warm autumn day was just the best we could ask for."

Humpback whales are frequent visitors to New Zealand's coastal waters. They migrate between summer feeding grounds in Antarctica and winter breeding grounds in tropical waters.

The Oceania population of humpback whales has been classified as "endangered" by the International Union for Conservation of Nature since 2008.

Humpback whales have a small dorsal fin with a distinctive hump at the front, and knobbly protuberances on the head, tip of the lower jaw and leading edge of extremely long flippers.

Their tail flukes are broad and have a unique black-and-white pattern, which allow individuals to be identified. Their colour varies, but they are generally black with white on the underside and on the flippers.

Newborn humpback whales are between 4 and 5m long, and adults range between 11.5 and 15m, according to the Department of Conservation.