Wiens, J.D., K.M. Dugger, K.E. Lewicki, and D.C. Simon. 2016. Effects of experimental removal of barred owls on population demography of northern spotted owls in Washington and Oregon - 2015 Progress Report. U.S. Geological Survey Open-File Report 2016-1041, 16 p., https://dx.doi.org/10.3133/ofr20161041. [IP-072911, approved 3/11/2016]
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