Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Raymond J. Davis; Bruce Hollen; Jeremy Hobson; Julia E. Gower; David Keenum
    Date: 2016
    Source: Gen. Tech. Rep. PNW-GTR-929. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 54 p.
    Publication Series: General Technical Report (GTR)
    Station: Pacific Northwest Research Station
    PDF: Download Publication  (15.0 MB)


    This is the third in a series of periodic monitoring reports on northern spotted owl (Strix occidentalis caurina) habitat status and trends on federally administered lands since implementation of the Northwest Forest Plan (NWFP) in 1994. The objective of this monitoring is to determine if the NWFP is providing for conservation and management of northern spotted owl (NSO) habitat as anticipated. This report focused on the amount, distribution, and spatial arrangement of NSO habitats across the NWFP area; and how these have changed as a result of disturbance and ingrowth starting with the year of the NWFP analyses in 1993. Results showed a net decrease from 9,089,700 ac to 8,954,000 ac (-1.5 percent) of nesting/roosting habitat on NWFP federal lands. This occurred despite gross losses from wildfire of 5.2 percent (474,300 ac), 1.3 percent from timber harvest (116,100 ac), and 0.7 percent from insects or other causes (59,800 ac), indicating that processes of forest succession have compensated for some of the losses resulting from disturbance. Dispersal habitat on NWFP federal lands increased by 2.2 percent (net change), but dispersal-capable landscapes experienced a 5 percent net decrease owing to habitat losses on the surrounding nonfederal lands. Large wildfires continue to be the leading cause for loss of NSO habitat on federal lands. Most of these losses occurred within the network of large reserves designed for NSO conservation.

    Publication Notes

    • Visit PNW's Publication Request Page to request a hard copy of this publication.
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.


    Davis, Raymond J.; Hollen, Bruce; Hobson, Jeremy; Gower, Julia E.; Keenum, David. 2016. Northwest Forest Plan—the first 20 years (1994-2013): status and trends of northern spotted owl habitats. Gen. Tech. Rep. PNW-GTR-929. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 54 p.


    Google Scholar


    Northwest Forest Plan, effectiveness monitoring, northern spotted owl, MaxEnt, owl habitat, habitat suitability.

    Related Search

    XML: View XML
Show More
Show Fewer
Jump to Top of Page