This resulted in the design and development of purpose built waterproof drones for sampling whale blow using a non-invasive collection technique.
Over a two-day period, the drones were used to collect 57 samples of exhaled breath condensate, or ‘blow’ from northward migrating humpback whales off Sydney. The drone collection technique eliminates the need to make close boat approaches which are dangerous for both the whales and scientists.
Lead author Vanessa Pirotta said “this is not only a much safer alternative to close vessel-based sampling but was also shown to be non-invasive, as there was no behavioural response to our drones”.
However, the challenge was not as simple as flying a drone over the top of a whale. Project microbiologist Dr Martin Ostrowski explained “microbes are everywhere, they are in seawater, air, dust, on the skin and in the breath of the scientists on the boat”.
To effectively target microbes living in whale blow the team designed a flip-lid sampler loaded with a sterile petri dish. The petri dish remained closed while the drone tracked each whale and opened briefly while flying through the blow just as the whale exhaled.
Preliminary data on seawater microbes obtained from the IMOS Port Hacking National Reference Station (NRS) allowed the researchers to gauge the success of the technique. “One of the unexpected challenges was extracting the DNA from a very small amount of sample material, typically we captured a fine spray equal to 2-3 drops of whale snot with each flight”.
Access to the Bioplatforms Australia/IMOS Marine Microbes data for an annual cycle enabled the team to accurately determine which bacterial species were characteristic of seawater in the area and then precisely identify the species living in whale breath. This work provides a baseline of the microorganisms found in a healthy whale population and an efficient, safe method to continue screening migrating whale populations for respiratory diseases.
“Microbes are an intrinsic component of the health of all levels of marine ecosystems” says Dr Ostrowski, “baseline genomic data being produced as part of the Bioplatforms Australia -IMOS partnership will provide us with the framework to test the next generation of sensitive ecosystem diagnostic tools”. The team of researchers are currently developing methods to analyse viruses, hormones, and other chemicals that may allow us to integrate a range of indicators of whale health.
Reference: Pirotta V, Smith A, Ostrowski M, Russell D, Jonsen ID, Grech A and Harcourt R (2017) An Economical Custom-Built Drone for Assessing Whale Health. Front. Mar. Sci. 4:425. doi: 10.3389/fmars.2017.00425
Drone permitting statement:
The use of drones around wildlife is restricted and closer approach to marine mammals using drones is only permitted under a scientific licence and with Civil Aviation Safety Authority approval. Current restrictions when approaching a marine mammal in an unmanned aircraft (including drones) without a scientific licence specify that aircraft must maintain a height at least 100 metres above the animal/s and also maintain a 100 metres horizontal radius away from the animal/s, under the Biodiversity Conservation Regulation 2017 which came into effect on 25 August 2017.
This story was written by Vanessa Pirotta and Martin Ostrowski.