Emperor penguins are not only the largest penguin species, but also the ones that breed in the most isolated and difficult to reach place: the Antarctic fast ice. This makes it very complicated for researchers to obtain reliable data on colony size and composition, but in view of climate change this is essential information. A German research group has now studied how well the use of drones works in collecting population data and whether the animals are disturbed by the flying eyes.
The research team of the Thuringian Institute for Sustainability and Climate Protection ThINK concluded in their study that drones can be a very suitable means for collecting population data on emperor penguins. This is because aerial photography provides more detailed images of emperor penguin colonies than would be possible using satellite imagery, due to the lower altitude and the device staying in one place longer. “Potential colonies can be flown over in a few hours, and the images can be used to make accurate counts of the animals,” writes Marie-Charlott Rümmler of ThINK in an email to PolarJournal. “If taking into account some challenges and methodically plan for them beforehand, drones are a very good tool here, in our experience.”
In their work, the research team from ThINK had two different types of drones (an airplane-like fixed-wing drone and a classic quadrocopter) fly over the emperor penguin colony near the Neumayer III Antarctic Station on the one hand, and compared the image recordings with satellite data. It was found that for mapping tasks and population counts, especially when counting chicks, the drone provided excellent results. “With satellite images, usually only the guano areas of the colonies are visible,” explains Marie-Charlott Rümmler “Statements about how large a colony actually is, how many individuals, how many chicks are present, can hardly be made this way. Drones, on the other hand, offer a much higher resolution and therefore a more accurate picture of a colony.”
But drones are not the new panacea for collecting previously missing data on emperor penguins. This is because the climatic conditions in Antarctica, the location of the colonies and also possible disturbances of the animals form major hurdles in the use of the small flying machines. While the former factors can still be cushioned to some extent with the appropriate planning and equipment, disturbances and hazards to the animals from noise or the crash of a drone are clear “no-goes”. Therefore, ThINK researchers also studied the influence on behavior in emperor penguins with chicks. During the experiments, the drones flew horizontally over the colonies at an altitude of between 20 and 120 meters and studied the behavior. Here it was shown that the animals, especially the adults hardly took notes from the drones. “We observed that most emperor penguins reacted to drones for less than 1 minute and also showed hardly any strong reactions such as escape behavior or alarm signals,” says Marie-Charlott Rümmler. But she cautions against generalizing the results. “More caution is needed for other types of use, such as film projects. This is because other flight patterns are used there and we have seen that chicks in particular react more strongly to the vertical approach, i.e. from above, with flight behavior and significant stress,” she continues. “It could be that the animals are interpreting this as an attack by a skua or a giant petrel.”
Using drones to survey the emperor penguin colony could also help show if and how the animals are responding to the decline of their breeding habitat, fast ice. Indeed, research teams have calculated that in the worst-case scenario of global warming, virtually all colonies would be negatively affected and many could even disappear completely. While only a few colonies have been found to lose fast ice and move to nearby and accessible ice shelves, the number of colonies that have lost fast ice is still very small. But not all colonies have such alternative sites. Ice ramps are important, providing a way for penguins to access the higher ice shelf. This has already been observed in Atka Bay.
In addition to the possible collapse of fast ice, other factors affect the survival of the species, especially the chicks. Experts cite increased precipitation in the form of rain, reduced food availability, or earlier ice breakup as examples. A recent study showed that the colony at Halley Bay in 2021 had experienced complete brood failure for the fourth time since 2009. Although this is only the tip of the iceberg, it shows very clearly what we can expect if global temperatures continue to rise and the scenarios that experts predict for Antarctica actually come to pass. In any case, they do not bode well for the little gray and white fluffy balls and their striking parents.
Dr Michael Wenger, PolarJournal
Link to the original publication of the ThINK research group:
Rümmler et al (2021) Remote Sens Appl: Soc Environ 23 (100545) Emperor Penguin Reactions to UAVs: First Observations and Comparisons with Effects of Human Approach; https://doi.org/10.1016/j.rsase.2021.100545
Rümmler et al (2021) Remote Sens Appl: Soc Environ 23 (100558) Effects of UAV Overflight Height, UAV Type, and Season on the Behavior of Emperor Penguin Adults and Chicks; https://doi.org/10.1016/j.rsase.2021.100558
Link to the report for the Federal Environment Agency
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