Westside Elk Habitat Use Modeling
on the Umpqua National Forest
Josh Chapman and Justin Hadwen
Umpqua National Forest
Post Treatment
Canopy Closure
10
35
40
50
Total
Acres
33
230
1,329
1,074
2,666
Update Base Vegetation Variables
Post Treatment
Canopy Closure % Hardwood Total Acres
10
25%
33
35
25%
230
40
25%
1329
50
25%
1074
2666
Total
DDE Nutritional Rating Classes
Class
Description
Mean DDE
1
Poor
<2.40
2
Marginal
≥2.40 to <2.75
3
Good
≥2.75 to <2.90
4
Excellent
≥2.90
Acres of Predicted DDE
No Action
Alternative 2
DDE Class
Existing (NA)
Acres
Alternative 2
Acres
1 (Poor)
20927
19761
2 (Marginal)
12623
11706
3 (Good)
5135
6825
4 (Excellent)
3545
3938
Model Strengths
Good for comparison of Alternatives in visual
and numeric display
Relatively easy to run if you have GIS
experience
Model Weaknesses
Limitations in applicability to SW Oregon
currently, hopefully this will be addressed
through work this summer
Wildlife biologists without GIS experience will
be at the mercy of GIS specialists for
completing work
Works across land ownerships
Roads input layers (open vs. closed) are
challenging to ground truth
Works well on large projects, in particular
forest plan revisions, resource management
plans (BLM)
Does not work well on small projects, as
measurable differences at the 5th field
watershed cannot be acquired
Tied to elk reproductive rates, which has
population level impacts. Important for
Management Indicator Species analyses
where the FS is responsible for documenting
changing in population trends.
Reliance on GNN data to be updated into the
future
Some forested lands it is difficult to move
forage condition beyond marginal based upon
the nutritional equations.
Need to update base vegetation layers based
upon private land/fire disturbances on annual
basis.