Making good compromises in implementing wildlife linkage designs

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Making good compromises in implementing wildlife
linkage designs
Paul Beier, Northern Arizona University Jeff
Jenness, Jenness Enterprises
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32 linkage conservation plans in Arizona
California
Implementers response Nice plan. I cant
conserve that area. Would this make a good
corridor?
Optimal area to conserve for wildlife movement
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Making good compromises in implementing wildlife
linkage designs
The view from 50,000 feet Arizona Wildlife
Linkage Assessment
The view from 10,000 feet Santa
Catalina-Tortolita Mountains linkage the
biologically-optimum, politically ignorant plan
Corridor Evaluation Tools A set of ArcGIS tools
to help evaluate alternative linkage designs
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Sponsored by
The view from 50,000 feet Arizona Wildlife
Linkage Assessment
gt 100 participants from 20 agencies
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The view from 50,000 feet Arizona Wildlife
Linkage Assessment
Dec 2006 150 Linkages at risk
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The view from 50,000 feet Arizona Wildlife
Linkage Assessment
Each Potential Linkage is a blob of private and
state land
only part of which will need to be conserved.
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The view from 10,000 feet detailed linkage
designs
Arizona Missing Linkages ???
16 detailed linkage designs www.corridordesign.org

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The view from 10,000 feet detailed linkage
designs
??? Tortolita Mountains-Santa Catalina Mountains
Linkage Design
Tucson
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The Tortolita-Catalina linkage was designed
primarily to serve 10 focal species.
Other species considered Arizona Whipsnake,
Coachwhip, Giant Spotted Whiptail, Gopher Snake,
Lowland Leopard Frog, Mohave Rattlesnake, Sonoran
Desert Toad, Sonoyta Mud Turtle, Tiger
Rattlesnake, Western Diamondback Rattlesnake
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The view from 10,000 feet detailed linkage
designs
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No species left behind
Broad, multi-strand linkages minimize edge
effects, promote ecosystem processes, and serve
species not modeled.
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The view from 10,000 feet The biologically
optimum plan Based only on biological
considerations
Test Alternative Corridors
Linkage Design released June 20, 2008
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Town of Oro Valley has slated part of the linkage
design for development.
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Aug 2008 Oro Valley proposes to annex 14,000
acres of ASLD land.
The plan included a compromise corridor!
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So Is this a good compromise or a bad one?
This is a job for
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So Is this a good compromise or a bad one?
This is a job for
Corridor Evaluation Tools (an ArcGIS extension)
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Corridor Evaluation Tools identify good corridors
five ways!
Bottlenecks within a corridor
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Corridor Evaluation Tools identify good corridors
five ways!
Longest distance between riparian areas (or any
habitat feature).
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Corridor Evaluation Tools identify good corridors
five ways!
Frequency distribution of modeled habitat quality
for each focal species.
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Corridor Evaluation Tools identify good corridors
five ways!
Wildland Block 1
Longest distances between adjacent steppingstones
for each focal species.
Wildland Block 2
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Corridor Evaluation Tools identify good corridors
five ways!
Pressure for urban development
Number of Parcels Number of Parcels Parcel Size Parcel Size Parcel Size Parcel Size
Number of Parcels Number of Parcels 0-3 acres 3-10 acres 10-100 ac gt 100 ac
Distance to paved road (m) 0-250 7 5 8 3
Distance to paved road (m) 250-500 12 4 9 5
Distance to paved road (m) 500-1000 23 0 6 8
Distance to paved road (m) gt1000 0 0 22 9
Alt A
Number of Parcels Number of Parcels Parcel Size Parcel Size Parcel Size Parcel Size
Number of Parcels Number of Parcels 0-3 acres 3-10 acres 10-100 ac gt 100 ac
Distance to paved road (m) 0-250 75 12 3 0
Distance to paved road (m) 250-500 125 4 8 3
Distance to paved road (m) 500-1000 0 0 8 4
Distance to paved road (m) gt1000 0 0 15 2
Alt. B
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Alt 1 The full linkage design (19,300 acres)
SR-77
Most natural
Oro Valley
Least natural
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Alt 2 ASLD- Oro Valley proposal (3,300 acres)
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Alt 3 Shortest major floodplain (790 acres all
free)
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Frequency distribution of modeled habitat quality
for each focal species.
The 3 alternatives offer similar habitat quality
for most focal species.
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Frequency distribution of modeled habitat quality
for each focal species.
The 3 alternatives offer similar habitat quality
for most focal species.
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Frequency distribution of modeled habitat quality
for each focal species.
The worst performances of the ASLD/Oro Valley
alternative were for Gila monster desert
tortoise.
Not so bad at all!
Breeding habitat 30? 22
Breeding habitat 26? 19
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Bottlenecks within the corridor
Full linkage design
ASLD/Oro Valley 1 bottleneck, 1005 m long mean
width 1300 m
Floodplain 100 bottlenecked mean width 175 m
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Longest distances between riparian areas
Combine ASLD/Oro Valley plan with floodplain
protection
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Longest distances between adjacent steppingstones
of modeled breeding habitat for each focal species
Wildland Block 1
Floodplain corridor had longer interpatch
distances than the full Linkage Design or
ASLD/Oro Valley alternatives for badger.
Wildland Block 2
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The floodplain corridor also had longer
interpatch distances for kit fox, mule deer, and
bobcat.
For these highly mobile species, these gaps are
probably trivial.
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ASLD/Oro Valley alternative for desert tortoise
may be significantly worse than full Linkage
Design.
Tortoises have been documented to move much
longer distances.
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So Is this a good compromise or a bad one?
Yes. Slightly narrower than the full linkage
design. longer gaps between riparian areas
between breeding patches for tortoise. But
overall a good compromise.
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Corridor Evaluation Tools
Three special thank-yous
Sherry Ruther, Biologist, Pima County
Sarah More, Planner, Town of Oro Valley
Michele Muench, Planner, ASLD