This drone footage of right whales was taken during a recent University of Otago expedition to the Auckland Islands.
Scientists have successfully used drones to capture detailed images of Southern right whales during an expedition to New Zealand's naturally hostile subantarctic islands.
An international team of researchers aboard Otago University's research vessel RV Polaris II last week returned from a month-long voyage to the wild and windy Auckland Islands, 465km south of Stewart Island.
The team sought to gauge the status of right whales, which breed at Port Ross, and gain a deeper insight into how a warming world was affecting one of the most sensitive parts of the globe.
They also sought 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.
Along with photographic surveys of the whales from small boats, the expedition used a drone - a small four-rotor helicopter equipped with a high-resolution camera - to document the condition of individual whales.
"We fitted our drone with a tiny laser range-finder to measure altitude with a high degree of precision," said expedition leader and Otago University marine biologist Professor Steve Dawson.
The technology allowed the researchers to measure the size and shape of right whales photographed from above.
"This helps us understand the population at the Auckland Islands, and is crucial for figuring out why some right whale populations, such as ours, are recovering strongly, while others, such as the North Atlantic right whale, are not," he said.
"The pictures were taken while the drone hovered 25 to 35m above the whales and the whales did not seem to react.
"I don't think they knew the drone was there which means this technology provides a powerful non-invasive tool to assess the condition of individual whales."
Despite the Auckland Islands being famously windy, the expedition was blessed with light winds and calm seas.
In previous voyages, researchers have had to contend with five to six-metre swells.
"In three weeks on site, we were able to fly our drone a total of 136 flights on 12 days - far more than we expected."
The team gained measurement-quality images of more than 100 different individuals - about a third of the whales present.
"That's a great sample, but we're most excited about getting measurement images of over 50 mothers and calves because these are the ones driving the population's recovery."
The pictures weren't all the team came back with: bacterial samples, blown directly out of the whales, were able to be collected when they came close enough to the boats.
The expedition was funded by the New Zealand Antarctic Research Institute (NZARI), which is committed to supporting cutting-edge research that contributes to better understanding of Antarctica and the Southern Ocean.
Drones were used to capture these images of Southern right whales near the sub-antarctic Auckland Islands. Photo: supplied
"This expedition is a great example of the kind of research NZARI supports - using new technology to learn more about how our southern ecosystems function and how we might use that to understand future changes," NZARI director Professor Gary Wilson said.
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.
