April 2012 Version
Appendix IV
Regional Transect Establishment Methodology
Transects were established at the regional level by the Regional Office the methodology outlined
below. GIS data are located in the WHWO_Transects.gdb geodatabase and the
WHWOTransects.mxd ArcMAP project (on file in the Pacific Northwest Regional Office). The
process is also documented using Model Builder in ArcMAP.
Step 1
Gradient Nearest Neighbor (GNN) data were used to classify 30 x 30 m pixels into potential
habitat and non-habitat. Potential habitat was defined as having ponderosa pine, sugar pine,
white pine or Jeffery pine dominant or codominant species.
Step 2
The vegetation data base was too large to run spatial statistics at the regional scale. The reagion
was divided by Omernik Ecoregion for Oregon (East Cascades & Blues) and Washington (North
Cascades & Rockies combined). The process is documented in Model builder: extractbystateER
Step 3
The vegetation data were extracted US Forest Service lands only. The process is documented in
Model builder: extractUSFS
Step 4
The following spatial statistics were used to eliminate noise from the potential habitat vegetation
data and develop polygons available for transects. Polygons were continuous areas with at least
50% potential habitat at the scale of 300 x 300 meters (distance between points along transects).
 3 majority filters to “clean” data – model builder: majority filter
 Block Statistics – 10x10 cells (300x300m) – model builder: block
 Reclassify to: > 50 = “50”, and <50 = “0” – model builder: reclassify50plus
 Extract cells = 50 – model builder: extract50plus
 Convert raster to polygon and then combine into one feature polygon for each region
o Create polygon – model builder: rastertopoly
o Dissolve polygon – model builder: Dissolvepoly
Step 5
Random transects were established in the polygons using the NPS AlaskaPak Toolkit (National
Park Service, Anchorage, AK), random transects function. The following inputs were used:
 Run on dataframe
 Transects per feature = 60 Oregon ERs, 20 for Washington ERs
 Min length = 2700
 Max length = 2700
 Attempts =1000 Oregon ERs, 2000 for Washington ERs
 Do not allow overlap
April 2012 Version
Step 6
The transects were first validated by regional personnel using National Agriculture Imagery
Program (NAIP09 4 Band) imagery.
(http://www.fsa.usda.gov/FSA/apfoapp?area=home&subject=prog&topic=nai). Potential
transects were then sent to field supervisors for final validation based on occurrence in potential
habitat and logistic feasibility (within 500 m of an open road).
Step 7
Final transects were selected based on input from field supervisors.
 Transects were eliminated if they weren’t within potential habitat or logistically feasible
 Final transects were selected, starting at the top of the random list generated by
AlaskaPak, until the appropriate number of transects were identified for each crew. Final
transects were at least 10 km apart.
o Washington crew – 4 transects
o Blue Mountains crew – 12 transects
o East Cascades crew – 11 transects
 The remaining transects were identified as substitutes if the selected transects do not meet
protocol criteria during layout.
In addition 3 transects were selected for the East Cascades crew from the model validation
transects established by Rocky Mountain Research Station.