Wildlife Acoustics

Declining in numbers from the pressures of climate change, habitat loss, fragmentation, and more, nocturnal birds are fighting the good fight. And researchers are joining in. Using the Force (ahem, bioacoustics) for good, scientists are monitoring every hoot, bark, scream, and whistle to ensure their conservation. How are they doing it? Find out at our FREE webinar on May 4th. ---- Talks & Presenters How to Stay Lazy: Surveying Nocturnal Birds, While Staying in Bed Nocturnal birds are difficult to survey: you can hardly see them, and they're active when we don’t want to be. But many nocturnal birds are rare and declining, and as conservationists we can’t ignore them. Automated acoustic monitoring is, therefore, a great option for gathering data on their presence, distribution, and numbers (while getting a full eight hours of shut-eye and preventing sleep deprivation). This talk will cover some recent studies on nocturnal birds, describing the methods used, the results gathered, and how they might be applied to nature conservation—including the development of methods guidance. Dr Carlos Abrahams, BSc, PgC, MSc, MCIEEM Director of Bioacoustics Baker Consultants Matlock, Derbyshire, United Kingdom ---- Using Acoustic Monitoring to Detect Barn Owls in an Area of Range Expansion Barn owls (Tyto alba) were generally considered extralimital in Minnesota until the International Owl Center’s fixed recording equipment picked them up in 2014, 2017, 2018, and 2019 during a great horned owl study. In 2020, the Center began using Song Meter Minis to detect barn owls in other locations in southeastern Minnesota and southwestern Wisconsin. Despite being strictly nocturnal and far less vocal than other owl species, barn owls were recorded at a variety of new locations. This research is largely responsible for doubling the number of barn owl reports in Minnesota in recorded history, and its state listing status will be reconsidered during the next review of rare species listings. This talk will cover methods used (equipment, software, and settings), location and length of recorder placement, what worked, what didn’t, and tricks that helped find barn owls in Kaleidoscope. Karla Bloem Founder & Executive Director The International Owl Center Houston, MN, United States ---- Passive Acoustic Monitoring of Northern Spotted Owls: This Is the Way Northern spotted owls (Strix occidentalis caurina) are an important indicator species for old-growth forests—a primary reason scientists have monitored their populations since the 1980s. Using mark-resight methods and call-back surveys, the results of spotted owl monitoring have significantly influenced large-scale land management and conservation decisions. However, traditional methods are increasingly expensive and less viable as spotted owl populations decline. Passive acoustic monitoring (PAM) provides an effective, non-invasive way to detect spotted owl presence and population trends, sex individuals, and estimate pair-occupancy rates. A key component of our monitoring program’s success has been the development of machine learning models that automate species detections and enable rapid data processing and analysis workflows. By leveraging new technologies, northern spotted owl monitoring will expand the scope of inference to broad biodiversity monitoring and better link to remote sensing datasets to support decision-makers facing challenges in dynamic landscapes. Damon B. Lesmeister, PhD Research Wildlife Biologist USFS | Pacific Northwest Research Station Oregon State University | Bioacoustics Lab Corvallis, OR, United States