Some of the most interesting research that I’ve gotten to do happens when threads of my research worlds collide. For a couple years now, I’ve had the chance to do acoustic monitoring on the Olympic Pensinula focused on detecting a new “species” on the landscape – in this case it’s a type of military aircraft, the EA-18G (aka Growlers). Since initially writing this blog post, the research findings have been peer-reviewed and published in the journal Northwest Science.
Spectrogram of 1 hour of aircraft events recorded on the Olympic peninsula. Spectrograms are visual renderings of audio data, with color indicating acoustic power at different frequencies.
The implications of increased military activity in this wilderness area have been widely reported by both local and national media, so I won’t get into that here. Beyond the conservation issue, however, for me this project exemplifies how the process of science benefits from working across disciplines and by open science: by borrowing the best concepts and methodologies, we can efficiently address new conservation problems as they emerge.
At the most basic level, this research comes down to a kind of occupancy-and-detection problem: how do we find and measure intermittent events over a large landscape? Layered on top of that are the technical issues of how to measure noise in ways that are meaningful for considering the impacts on people and wildlife. Lastly, noise in urban areas is one thing (often expected), but the “toll” of noise pollution in wilderness spaces is different, requiring insights into our psychological relationship with nature.
Projects like this allow me to appreciate opportunities that I’ve had to work across disciplines in the past, including work with Dr. Pooja Tandon (Seattle Children’s Research Institute) on nature-health research, a crowdfunded urbanization-noise study, and occupancy and detection modeling to find an elusive endemic fish. But really, this research was only possible because of the extraordinary work and commitment of other scientists in sharing methods and expertise via mentorship and amazing open-source resources. I’ve listed some below that I’ve absolutely relied on, but there are so many that a review is the best place to check them out. Here an (incomplete) list of resources/programs/software that made this project possible, in case that is useful to others embarking on related research:
- Audacity – amazing free software for audio editing
- Nathan Merchant’s PAMGuide for generating calibrated sound pressure levels from audio – be sure to cite the corresponding paper!
- US National Park Service Natural Sounds and Night Skies Division – these folks are producing a ton of awesome methods and work on measuring noise
- Cornell’s Center for Conservation Bioacoustics – always advancing the (acoustics) ball