Spatial Distribution and Demographic Patterns of the Northern Saw-whet Owl (Aegolius acadicus)

• Eli Hevalow, Wildlife Ecology and Conservation, University of Delaware

• Jeffrey Buler, Entomology and Wildlife Ecology, University of Delaware

This study analyzes capture and recapture data of the Northern Saw-whet Owl (Aegolius acadicus) to better understand spatial distribution patterns across different demographics. Utilizing a comprehensive dataset from the USGS Bird Banding Lab (BBL), which includes capture and recapture records from 1960 to 2023 across the United States and Canada, we aim to visualize these patterns more effectively. Data processing and analysis were conducted using R Studio and QGIS, resulting in the creation of four distribution maps correlating with various sex and age combinations. Findings reveal significant disparities in capture frequencies between male and female owls, highlighting a need for further investigation. To address this knowledge gap, we initiated additional banding efforts in Monongahela National Forest, West Virginia, where breeding populations are present. Deploying an audio-lure capture technique developed by Erdmen and Brinker (1997), we successfully captured and tagged owls. Each owl was sexed, aged, weighed, and equipped with both a cellular nanotag and a USGS leg band. The nanotag codes were subsequently registered with the Motus Wildlife Tracking System network, allowing for the monitoring of movement patterns and facilitating future data interpretation.