Collecting whale blow mucus by drone
A Macquarie University-led project provides a non-invasive way to monitor the health of whale populations.
Scientists are learning the potential for drones extends beyond missile launches or pizza deliveries to more edifying endeavours – such as collecting whale mucus.
Vanessa Pirotta, a researcher from Macquarie University, in Sydney, Australia, was keen to discover a less dangerous way of accessing exhalations from a whale’s blowhole than previous methods, such as manoeuvring a nylon stocking at the end of a very long pole.
An alternative was to extract the mucus from a beached whale – or one deliberately killed. The former, though, involved animals possibly compromised by ill-health, while the latter was, to Pirotta, “not desirable in the modern era”.
Drones offered a relatively low-cost device that could be modified to be water-proofed and to deploy a “flip-lid” to capture and store samples from whales as they ejected air through their blowhole, according to research published late last month in the Frontiers in Marine Science journal.
The technology could capture the essence of the spray while keeping researchers at a safe distance from mammals that can weigh as much as 80 tonnes.
The point of the collections – 59 samples in all, gathered last June only a few kilometres off Sydney – was to learn about the animals’ health based on the microbiota of the lungs of the northward-migrating whales.
“It’s a remarkable snapshot into what continue to be free-ranging, relatively healthy individuals,” Pirotta said, with DNA, bacteria and hormones among the material now being examined back in the laboratory.
The aim is to establish a baseline of health of the fast-recovering species. Humpback whales off Australia’s east coast are increasing at a remarkable 10 per cent or more per year, and now number about 30,000, researchers estimate.
“We can use this [data] as a potential tool for long-term health assessments to look at changes in a growing population,” Pirotta said.
Alastair Smith, the drone pilot, mastered the flying techniques. By the end, he could capture samples of a whale’s spray within a few minutes, while piloting the device from several hundred metres away, sometimes in rough weather.
“Getting two or three seconds’ worth of sprays can be quite difficult, and to return to the vessel and secure the sample is truly amazing,” Pirotta said.
The team had appropriate licences from the National Parks service of NSW, and from civil aviation safety authorities, she said.
The same techniques could be applied to gather information on humpback whales when they head south after mating in waters off Queensland.
Such a southward path is typically further out to sea compared with the northward journey from Antarctica that brings animals close to the coast from May onwards.
Likewise, drones could be deployed to gauge the health of other cetaceans, including southern right whales or dolphins, although the logistics of capturing sprays of the faster-moving mammals could be more a test of flying skills.
“We can use this technology to build up a picture,” Pirotta said. “It may also provide a snapshot of the ocean’s health as well.”
– Sydney Morning Herald