Wildlife Connectivity in the Sierra Nevada Foothills
Melanie Gogol-Prokurat, Crystal M. Krause and Simon Bisrat
Biogeographic Data Branch
California Department of Fish and Wildlife
[email protected]
Photos courtesy of the National Digital Image library
Importance of Habitat Connectivity

Provides paths for movement in the landscape
 Finding
food, cover, mates
 Migration
 Adaptation to climate change

Barriers to connectivity
roads, development, habitat conversion

AB2785 (2008)
Photos courtesy of the National Digital Image library
2010 California Essential Habitat
Connectivity (CEHC) Project

Natural Landscape
Blocks
– Contiguous natural
habitat
– > 2,000 acres

Connections
– Between blocks > 10,000
acres
– Least cost modeling
– Ecological integrity
Spencer et al., 2010
Scaling down:
the need for
fine-scale connectivity
mapping
CEHC
Fine-scale
Regional
NLB
>10,000
acres
<10,000
acres
Basis
Ecological Speciesintegrity
specific
Scaling down:
the need for
fine-scale connectivity
mapping
CEHC
Fine-scale
Regional
NLB
>10,000
acres
<10,000
acres
Basis
Ecological Speciesintegrity
specific
Scaling down:
the need for
fine-scale connectivity
mapping
CEHC
Fine-scale
Regional
NLB
>10,000
acres
<10,000
acres
Basis
Ecological Speciesintegrity
specific
Project Goals
 Develop
Decision Support Tools
– conservation prioritization
– land-use planning
– wildlife crossings/collision risk
 Develop
Guidance Materials
 Understand
how to most efficiently
identify linkages
Northern Sierra
Nevada Foothills
Study Area
– Provides important
connectivity and migration
corridors for large species
(e.g., deer)
– 85% in private ownership
– High development pressure
– Intersected by major
highways
– Completed fine-scale
vegetation map
Focal Species
Landscape Blocks
Methods
 Habitat
Analysis
– Maxent and BioView
 Least-Cost
Corridors
– Corridor Designer
 Patch
ArcGIS Toolbox
Analysis
– Corridor Designer ArcGIS Toolbox
– Conefor ArcGIS Toolbox
 Linkage
Design
– Corridor Evaluation Tools
ArcGIS Toolbox
Habitat
Analysis
Maxent - Species
distribution model

Statistical model:
Species location data
Climate, topography,
vegetation, hydrology
Expert opinion
vegetation model

CWHR expert ranked
habitat suitability
Final model chosen
by species experts
Phillips et al., 2006
http://www.dfg.ca.gov/biogeodata/cwhr/
Patch
Analysis
• Habitat threshold value to define “suitable” habitat.
• Population patch are areas of contiguous suitable habitat larger than
25 times the recorded average home range size
• Breeding patch are areas of contiguous suitable habitat as least 2
times the minimum recorded home range but less than the population
patch.
• Dispersal Distance was defined as the maximum recorded dispersal
distance for an individual.
Least-Cost Modeling
Black Bear
Identify the
best swath of
habitat for
species
movement.
Least-Cost Modeling
Black Bear
Least-Cost Modeling
Black Bear
47
105
81
98
85
66
134
99
84
Black bear corridors
measure dispersal
Black-tailed jackrabbit corridors
distance
Bobcat corridors
Dusky-footed woodrat corridors
Gray fox corridors
Mountain lion corridors
Mule deer corridors
Western gray squirrel corridors
Western pond turtle corridors
Least-Cost Modeling
Mountain Lion
Least-Cost Modeling
Mule Deer
Corridor Dwellers Patch Analysis
Linkage Analysis
246 linkages
connecting 198
landscape blocks
799 individual
species habitat
corridors
Total linkage area
is 1,143,696 ha.
Riparian Corridors
Brost and Beier, 2012
Land Facets
Canyon
Land Facet
Corridors
https://www.wildlife.ca.gov/Data/Analysis/Connectivity
BIOS: view and download datasets
https://map.dfg.ca.gov/bios/
Thank you!
 Wildlife
Conservation Board for
funding
 CDFW Wildlife Species experts
 Land managers and land trusts