Wiens, J.D., K.M. Dugger, D.B. Lesmeister, K.E. Dilione, and D.C. Simon. 2018. Effects of experimental removal of Barred Owls on population demography of Northern Spotted Owls in Washington and Oregon—2017 progress report: U.S. Geological Survey Open-File Report 2018–1086, 23 pp. https://doi.org/10.3133/ofr20181086.
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