Flying high-tech drones close enough to southern right whales to catch some of the bugs they blow out will help tell scientists more about the effects climate change is having on the planet.

An international team of scientists, led by Otago University marine biologist Professor Steve Dawson, this week leaves for the wild and windy subantarctic islands for a month-long expedition to shed more light on the nutrition of the big ocean mammals.

What insights they gain will help them discover more about how the species is faring here and around the world, along with how a warming world is affecting one of the most sensitive parts of the globe.

From small boats off the cold and stormy Auckland Islands, about 465km south of Stewart Island, Dawson and his colleagues will use drones mounted with cutting-edge photogrammetric camera technology.


The drones, fitted with a specially developed laser range-finder to measure altitude, will take images of whales precise enough to take highly detailed measurements from.

"This is really state-of-the-art stuff," Dawson said.

"But it's also going to be a very challenging part of the world to use this approach in, because it's extremely windy, wet and cold, and drones don't like any of those things."

At the same time, they're hoping the drones will be able to collect samples of the whales' blow as they exhale.

Southern right whale population off New Zealand appears to be increasing.
Southern right whale population off New Zealand appears to be increasing.

"That gives us what's called the respiratory biome -- we get the bugs that are in the blow, but it also allows us to measure things like stress hormones," Dawson said.

"It's another very powerful way to learn more about the different conditions that are faced by different populations."

The specific goal of the mission, supported by the New Zealand Antarctic Research Institute, is to find out more about the nutritional condition of breeding females.

The subantarctics are a key ground for right whales - they arrive there pregnant, give birth, and feed their calf, all over a period in which they cannot forage themselves.


"So they have to build up their condition to a really good state before they can do that successfully," Dawson said.

"The drones give us a way to assess what condition those females are in when they are breeding, and that provides insight into the condition and productivity of the Southern Ocean system."

The researchers want enough data to make useful comparisons with their counterparts the North Atlantic right whale, which now numbers only in its hundreds, to better understand the stresses on right whales globally.

Over recent years, there has been an increasing focus by scientists on the islands, which remain a global hotspot for marine life and one of the world's best vantage points for observing the earliest indicators of a changing climate and ocean.

Researchers are now advancing a proposal for an environmental research facility on the Auckland Islands to be named after explorer Sir Peter Blake, who observed alarming changes there in the months before his death in 2001.

Southern right whales

• During the breeding season in winter and spring, they are mostly found in the waters around the subantarctic Auckland and Campbell Islands but there are occasional sightings around mainland New Zealand.

• The New Zealand population appears to be increasing, based on a mark-recapture study of individuals from the subantarctics.

• Typically black in colour but can have irregular white patches and range in size from 4.5m-6m (newborn) and 11m-18m (adults).

• Their flippers are large and paddle-shaped, and although they're slow swimmers they can be very acrobatic. They are also inquisitive.