CORVALLIS, Ore. – Northern spotted owl populations are approaching or have already crossed functional extinction across large areas of the Pacific Northwest, a new study found. Researchers used artificial intelligence and advanced monitoring methods to assess long-term trends at an unprecedented scale. While northern spotted owl populations have declined for decades, this study identifies where populations are at or near functional extinction, meaning numbers are so low that they no longer play a meaningful ecological role or cannot reproduce enough to persist. It also provides detailed population data on barred owls, which outcompete northern spotted owls for prey and habitat. “These findings demonstrate that passive acoustic monitoring and machine learning can be used for large-scale ecological monitoring,” said Damon Lesmeister, a wildlife biologist at the U.S. Forest Service’s Pacific Northwest Research Station and a courtesy faculty member at Oregon State University.