Our team of UAV operators, land-based observers and myself are back from a successful field trip, where for the first time, we tested the UAV for conducting humpback whale aerial surveys.
We conducted over 50 hours of UAV flights and collected thousands of images, which now need to be reviewed (by me – gulp!).
The ScanEagle was operated from a beach near Amity, Stradbroke Island, where the launch and recovery of the UAV became a bit of a spectacle for some of the locals. Most flights consisted of line transect surveys off Point Lookout, which covered the area that could be seen by our team of land-based observers.
While the ScanEagle captured still images covering the entire survey area, the land-based observers recorded all whales passing through the area, using a theodolite (surveyor’s tool) to mark their positions.
The two datasets will now be compared to determine what proportion of whales that were in the survey area, were actually capture by the UAV.
Our second objective was to trial the UAV with an infrared camera. We managed to capture some whale images using Short Wave Infrared, and these images can now be assessed for the potential additional information they might provide for whale surveys.
We also decided to spend time trying to conduct focal follows of whale pods (i.e. keep track of a whale pod using the ScanEagle’s video camera), to determine whether we could use that technique to assess the proportion of time a whale is actually visible from the air. This information will help us correct our counts for the whales that were missed because they were underwater (which we call their ‘availability’).
The focal follows were quite successful – some whales were followed for up to an hour. We were able to keep track of the whales from an altitude of over 2000 ft, meaning that our UAV was having no impact on the whale’s behaviour (the UAV makes very little noise compared to a normal plane). This bodes well for assessing the availability of whales during UAV surveys in the future.