Location of study: Klamath National Forest, Goosenest Ranger District, Macdoel, CA

1. Northern Goshawk Nest Site
Preference
Rose Kaforski
Debra Freeling, GNRD Wildlife Biologist
Klamath National Forest, Goosenest Ranger District
SPEA-E 490, Indiana University

2. Introduction
The northern goshawk (Accipiter
gentilis) is a large, predacious raptor
that generally lives in northern
coniferous forests, but can also be
found across southwestern USA and in
Europe. It has been recognized as a
sensitive species as well as a
“management indicator species” by a
large number of US national forests.

3. Introduction cont.
Klamath National Forest is one
of the forests that designates
the NOGO as a sensitive species
and is required to “evaluate the
effects of proposed
management actions on
goshawks and document the
findings in a biological
evaluation…”.

4. Research Question
In order to contribute to the USFS mission, I decided to collect and
analyze meaningful data and aimed to answer the following:
What type of nest site do northern goshawks prefer in
the Goosenest Ranger District?

5. Methods
Where are
nest sites
located? What
data is
needed?
• Field work & GIS
Where have
NOGOs nested
in past years?
• Data mining
What variables
contribute to
nest site
choice?
• Data analysis

6. Methods cont.
• Visited nest sites shown on GIS maps and
collected Northern Goshawk dataField Work
• Reviewed past data sheets to find information
on existing nest sites in each territoryData Mining
• Categorized data into tree type, dbh (diameter
at breast height), nest height, and nest aspectData Analysis

7. Results: Tree Type
26%
65%
9%
Pine
Fir
Unknown

8. Results: Diameter at Breast Height (dbh)
• Range: 4.5 – 49.4 in.
• Mean: 22.7 in.
• Median: 22.7 in.

9. Results: Nest Placement
• Height above ground
• Mean: 47.5 ft
51-75 ft: 25.6%
26-50 ft: 57.7%
0-25 ft: 3.9%
Unknown: 12.8%

10. Results: Nest Aspect
The largest fraction
of known nest
aspects, the
direction they faced
on the trees, were
between E (90º) and
S (180º)

11. Summary
Fir tree (typically White Fir) Average dbh of 22.7”
25-50’ above the ground Aspect of 90-180º
Preferred Nest Site in
Goosenest Ranger District

12. Conclusion
Sensitive species status means that KNF Wildlife
Department is responsible for collecting “information on
status and trends of northern goshawk populations and
habitats”.
Information on nest site preference in the Goosenest
Ranger District contributes to the understanding of
NOGOs and what type of forest habitat they may thrive
in, which aids in forest management decisions and
overall health of the forest.

13. References
"Northern Goshawk." Audubon. N.p., 01 Mar. 2016. Web. 04 Aug. 2017.
"Northern Goshawk." , Identification, All About Birds - Cornell Lab of Ornithology. Web. 04 Aug. 2017.
Woodbridge, B.; Hargis, C.D. 2006. Northern goshawk inventory and monitoring technical guide. Gen. Tech. Rep. WO- 71.
Washington, DC: U.S. Department of Agriculture, Forest Service. 80 p
Images
White Fir. Conifers and Trees of the American West. Digital Image. 16 June 2013. Web. 04 Aug. 2017.
Dbh Photograph. I-Tree Selector - Initial Question 7. Digital Image. Web. 04 Aug. 2017.
Compass. Heading Compass Gauge in Mathematica 9 - Online Technical Discussion Groups—
Wolfram Community. Digital Image. Web. 04 Aug. 2017.
Two goshawk nestlings in a newly discovered nest in Piñon Pine, an uncommon nesting substrate. "Rob's Idaho Perspective." 01
Jan. 2015. Web. 04 Aug. 2017.
Nestlings ready to fledge in the City of Rocks National Reserve. "The Ins and Outs of IBO's Northern Goshawk Research Project."
Digital Image. Intermountain Bird Observatory. N.p., 29 Oct. 2015. Web. 04 Aug. 2017.
Northern Goshawk. Teton Raptor Center. N.p. Digital Image. Web. 04 Aug. 2017.
Gleason, Dan. Northern goshawk range map. Digital image. Cascadesraptorcenter.org. Web. 4 Aug. 2017.