Skip to main content
U.S. flag

An official website of the United States government

Recent evidence suggests that frequency of breeding dispersal – the movement from one breeding territory to another – may be increasing in northern spotted owl populations, which could have consequences on population dynamics of this declining species.

Federal and university researchers examined rates and possible causes of breeding dispersal of 4,118 northern spotted owls monitored in Oregon and Washington from 1990 to 2017. The percent of spotted owls dispersing from their territories each year increased by greater than 17 percent during the study. This coincided with a rapid increase in numbers of invasive barred owls as they displaced spotted owls from their preferred breeding sites. Probability of breeding dispersal also increased for single owls and those that had also dispersed the previous year. Spotted owls were less likely to leave high-quality territories with historically high levels of successful reproduction. Findings highlight nuanced interactions between intrinsic and extrinsic factors that contribute to changes in dispersal behavior and population dynamics of an increasingly threatened old-forest species.

Jenkins, J.M., Lesmeister, D.B., Forsman, E.D., Dugger, K.M., Ackers, S.H., Andrews, S., Gremel, S.A., Hollen, B., McCafferty, C.E., Pruett, M.S., Reid, J.A., Sovern, S.G., Wiens, J.D., 2021, Conspecific and congeneric interactions shape increasing rates of breeding dispersal of northern spotted owls: Ecological Applications, no. e02398.

Get Our News

These items are in the RSS feed format (Really Simple Syndication) based on categories such as topics, locations, and more. You can install and RSS reader browser extension, software, or use a third-party service to receive immediate news updates depending on the feed that you have added. If you click the feed links below, they may look strange because they are simply XML code. An RSS reader can easily read this code and push out a notification to you when something new is posted to our site.