Regional Ecosystem Office (REO) - Northwest Forest Plan

Interagency Regional Monitoring: Northern Spotted Owl

Owl monitoring Photo Collage

The Northern Spotted Owl (NSO) Monitoring Program conducts long-term monitoring of NSO populations and habitat to determine the effectiveness of federal forest management on maintaining and restoring habitat conditions necessary to support viable populations of NSO on federally-administered forests throughout its range. Main objectives are to:

  1. Track status and trends of NSO populations on federal forests within its geographic range in the United States.
  2. Track status and trends in the amount and distribution of NSO forest cover types and habitat on federal forests.

Population monitoring was designed to occur in two phases. Phase I continued the pre-existing demographic studies scattered throughout the owl’s range. As such, demographic parameters were used as monitoring indicators. Phase II relies on a predictive modeling approach informed by habitat and passive bioacoustics monitoring. Under this approach, population size and distribution become the monitoring indicators.

As of 2023, Phase I monitoring was decommissioned, and Phase II monitoring was fully implemented using a random census design for all federally managed forests within the northern spotted owl’s range (in the US). For more details click on the following links:

Contact Information

Reports

Time Five-Year Monitoring Reports
25-Year Habitat Davis, Raymond J.; Lesmeister, Damon B.; Yang, Zhiqiang; Hollen, Bruce; Tuerler, Bridgette; Hobson, Jeremy; Guetterman, John; Stratton, Andrew. 2022. Northwest Forest Plan—the first 25 years (1994–2018): status and trends of northern spotted owl habitats. Gen. Tech. Rep. PNW-GTR-1003. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 38 p.
25-Year Population Franklin, A.B. et al. 2021. Range-wide declines of northern spotted owl populations in the Pacific Northwest: A meta-analysis. Biological Conservation, Volume 259, July 2021, 109168, ISSN 0006-3207.
20-Year Population Dugger, K. et al. 2016. The effects of habitat, climate, and Barred Owls on long-term demography of Northern Spotted Owls. The Condor. 118:57-116.
20-Year Habitat 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.
15-Year Davis, Raymond J.; Dugger, Katie M.; Mohoric, Shawne; Evers, Louisa; Aney, William C. 2011. Northwest Forest Plan—the first 15 years (1994–2008): status and trends of northern spotted owl populations and habitats. Gen. Tech. Rep. PNW-GTR-850. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 147 p.
10-Year Lint, Joseph, tech. coord. 2005. Northwest Forest Plan—the first 10 years (1994–2003): status and trends of northern spotted owl populations and habitat. Gen. Tech. Rep. PNW-GTR-648. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 176 p.
Monitoring Plan Lint, Joseph; Noon, Barry; Anthony, Robert; Forsman, Eric; Raphael, Martin; Collopy, Michael; Starkey, Edward. 1999. Northern spotted owl effectiveness monitoring plan for the Northwest Forest Plan. Gen. Tech. Rep. PNW-GTR-440. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 43 p.

Other Reports

Report Details
Lesmeister, D. B., J. M. A. Jenkins, Z. J. Ruff, R. J. Davis, C. L. Appel, A. D. Thomas, S. Gremel, D. Press, T. Chestnut, J. K. Swingle, T. Wilson, D. C. Culp, H. Lambert, C. McCafferty, K. Wert, B. Henson, L. Platt, D. Rhea-Fournier, and S. Mitchell. 2022. Passive Acoustic Monitoring within the Northwest Forest Plan Area: 2021 Annual Report. USDA Forest Service Pacific Northwest Research Station and USDI National Park Service. Corvallis, OR. 30 p.
D. Lesmeister et al. 2018. Demography of spotted owls on the east slope of the Cascade Range, Washington, 1989-2017. Annual research report. USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR and Dept. of Fish and Wildlife, Oregon State Univ., Corvallis, OR. 26 p.
D. Lesmeister et al. 2018. Demographic Characteristics of Spotted Owls in the Oregon Coast Range, 1990-2017. Annual research report. USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR and Dept. of Fish and Wildlife, Oregon State Univ., Corvallis, OR. 25 p.
D. Lesmeister et al. 2018. Demographic characteristics of northern spotted owls (Strix occidentalis caurina) in the Klamath Mountain Province of Oregon, 1990-2017. Annual report. USDI Bureau of Land Management, Oregon State Office, Portland, OR. 21 p.
K. Dugger et al. 2016. Demographic characteristics and ecology of northern spotted owls (Strix occidentalis caurina) in the Southern Oregon Cascades. Annual research report. Oregon Cooperative Fish and Wildlife Research Unit (OCFWRU), Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR. 24 p.
D. Lesmeister et al. 2017. Demography of spotted owls on the east slope of the Cascade Range, Washington, 1989-2016. Annual research report. USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR and Dept. of Fish and Wildlife, Oregon State Univ., Corvallis, OR. 25 p.
D. Lesmeister et al. 2017. Demographic characteristics of spotted owls in the Oregon Coast Ranges, 1990-2016. Annual research report. USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR and Dept. of Fish and Wildlife, Oregon State Univ., Corvallis, OR. 25 p.
K. Dugger et al. 2016. The demography of northern spotted owls (Strix occidentalis caurina) on the Willamette National Forest, Oregon. Annual research report. Oregon Cooperative Fish and Wildlife Research Unit (OCFWRU), Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR. 52 p.
D. Lesmeister et al. 2016. Demographic characteristics of northern spotted owls (Strix occidentalis caurina) in the Klamath Mountain Province of Oregon, 1990-2016. Annual report. USDI Bureau of Land Management, Oregon State Office, Portland, OR. 19 p.
A. Franklin et al. 2016. Monitoring the population ecology of spotted owls (Strix occidentalis caurina) in northwestern California: Annual results, 2016. Annual progress report for Region 5, USDA Forest Service. Colorado State University, Ft. Collins, CO. 32 p.
D. Lesmeister et al. 2017. Demographic characteristics of northern spotted owls (Strix occidentalis caurina) in the Olympic National Forest, Washington, 1987-2016. Annual research report. USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR and Dept. of Fish and Wildlife, Oregon State Univ., Corvallis, OR. 13 p.
D. Lesmeister et al. 2017. Demographic characteristics of northern spotted owls (Strix occidentalis) on the Tyee Density Study Area, Roseburg, Oregon: 198512016. Annual research report. USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR and Dept. of Fish and Wildlife, Oregon State Univ., Corvallis, OR. 25 p.

For older reports see the document archive.

Data

Report Details
Glenn et al. (2017). Estimating density of a territorial species in a dynamic landscape. Landscape Ecol. 32:563-579.
20-Year Report
15-Year Report
https://www.fs.usda.gov/r6/reo/monitoring/northern-spotted-owl.php