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Best Practices Manual: Wildlife Vehicle Collision Reduction Study

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List of Figures

Figure 1. Strategies for reducing WVCs
Figure 2. Regional planning as part of a strategy for reducing WVCs
Figure 3. Road sections prioritized for habitat connectivity in South Florida
Figure 4. Mitigation on the roadway may have only moved the problem to the railroad
Figure 5. Corridor planning and design as part of a strategy for reducing WVCs
Figure 6. Basic wildlife movements
Figure 7. Example of box beam guardrail
Figure 8. Long sections of median barriers are thought to increase road mortality and reduce animal movements across the road
Figure 9. Concrete barriers with scuppers that allow small and mid-sized species to cross under the median barriers
Figure 10. Opening in median barriers designed to allow wildlife to cross the road and the median barriers
Figure 11. Schematic representation of home ranges for two theoretical species projected on a road, and the distance between safe crossing opportunities
Figure 12. Schematic representation of home ranges for three individuals (x, y and z) with different locations for the center of each home range
Figure 13. Best practices for WVCs involving large animals, as part of the strategy for reducing WVCs
Figure 14. A 2.4-m-high (8-ft-high) large-mammal fence, with smaller mesh sizes toward the bottom, on U.S. Highway 93 on the Flathead Reservation in Montana
Figure 15. A moose fence, along the Glenn Highway (Hwy 1), northeast of Anchorage, AK
Figure 16. A 3.4-m-high (11-ft-high) chain-link fence along SR 29 in southern Florida, designed to keep Florida panthers off the roadway and to guide them toward underpasses.
Figure 17. A 3.4-m-high (11-ft-high) chain-link fence along SR 29 in southern Florida equipped with three strands of outrigged barbed wire to prevent Florida panthers from climbing the fence
Figure 18. Schematic drawing of a large-mammal fence in combination with barriers for smaller species
Figure 19. Large-mammal, medium-mammal and small-animal fence combined at the approach to the De Borkeld wildlife overpass across the A1 motorway in The Netherlands
Figure 20. A 2.4-m-high (8-ft-high) large-mammal fence with smaller mesh sizes toward the bottom and additional buried apron (dig barrier) along U.S. Highway 93 in Montana
Figure 21. Fence mesh attached to the side away from the road on wildlife fence along Interstate 90 near Bozeman, MT
Figure 22. Large-mammal fence with protective top cable along the Trans-Canada Highway in Banff National Park, Alberta
Figure 23. A 1.83-meter-high (6-ft-high) chain-link fence along U.S. Highway 1 on Big Pine Key, FL, with a 10-cm (4-in) gap allowing the endangered Lower Keys marsh rabbit access to the right of way (copyright: Marcel Huijser)
Figure 24. A chain-link moose fence near Kenai, AK, with a gap (and a barbed wire strand) at the bottom allowing small species to crawl underneath the fence
Figure 25. Fence end at top of cliff along U.S. Highway 93 in Montana
Figure 26. Fence end at bottom of cliff along U.S. Highway 93 in Montana
Figure 27. Fence end brought close to the road with a concrete barrier for safety in Banff National Park, just west of Castle Junction, Alberta
Figure 28. The boulder field at the fence end at Dead Man's Flats along the Trans-Canada Highway east of Canmore, Alberta
Figure 29. Wildlife guard at a fence end on the two-lane U.S. Highway 1 on Big Pine Key, FL
Figure 30. A short section of perpendicular fence to guide animals on top of a jump-out along a 2.4-meter-high (8-ft-high) fence along U.S. Highway 93 in Montana
Figure 31. A jump-out along a 2.4-meter-high (8-ft-high) fence along U.S. Highway 93 in Montana
Figure 32. A jump-out intended for Eurasian badger and roe deer along a 2-meter-high (6.6-ft-high) fence along the A73 motorway near Roermond, The Netherlands. Note the wildlife overpass "Waterloo" in the background
Figure 33. A jump-out along a 2.4-meter-high (8-ft-high) fence with smooth metal to prevent bears from climbing into the right of way along the Trans-Canada Highway, Banff National Park, Alberta
Figure 34. A one-way Eurasian Badger gate in the Netherlands
Figure 35. A 1.83-meter-high (6-ft-high) chain-link fence along U.S. Highway 1 between Florida City and Key Largo, FL, has been coated with colored plastic
Figure 36. A 2.4-meter-high (8-ft-high) large-mammal chain-link fence along the Trans-Canada Highway between Canmore and Banff, Alberta, is equipped with green mesh to make the fence more visible to bighorn sheep
Figure 37. A wildlife guard, similar to a standard cattle guard, at an on-ramp to Interstate 90 east of Bozeman, MT
Figure 38. A wildlife guard, similar to a standard cattle guard, at a forest access road connecting to the road "Hilversumsestraatweg", near Hilversum, The Netherlands
Figure 39. A modified wildlife guard (bridge-grate material) at an access road on U.S. Highway 93, south of Ravalli, MT
Figure 40. An escape ramp for small species from a wildlife guard pit near the town "De Lage Vuursche", The Netherlands
Figure 41. An escape ramp for small species from a wildlife guard pit along the road "Hilversumsestraatweg", near Hilversum, The Netherlands
Figure 42. A gate at an access road on U.S. Highway 93, north of Ravalli, MT
Figure 43. A swing gate for pedestrians and a wildlife guard at a bicycle path into an enclosure with large mammals (cattle), near the town "De Lage Vuursche", The Netherlands
Figure 44. Spring-loaded swing gate in fence allowing access for people along the Trans-Canada Highway in Banff National Park, Alberta
Figure 45. Access point for people along U.S. Highway 93 south of Missoula, MT
Figure 46. An open-span bridge over Spring Creek, along U.S. Highway 93 south of Ravalli, MT
Figure 47. A large-mammal underpass (7-8 m (23-26.2 ft) wide, 4-5 m (13.1-16.4 ft) high) along U.S. Highway 93 south of Ravalli, MT
Figure 48. A medium-mammal box culvert (1.2 m (3.9 ft) wide, 1.8 m (5.9 ft) high) along U.S. Highway 93, south of Ravalli, MT
Figure 49. A medium-mammal culvert (2 m (6.6 ft) wide, 1.5 m (4.9 ft) high) along U.S. Highway 93, south of Ravalli, MT
Figure 50. A small- to medium-mammal pipe (badger pipe) in The Netherlands (copyright: Marcel Huijser)
Figure 51. Wildlife underpasses are often installed in low-lying areas with road fill because construction costs are lower
Figure 52. Wildlife fencing ties in with the underpass wing walls, preventing animals from entering the road corridor
Figure 53. This fence post leaves more space than desired between the post and the wing walls of a crossing structure, allowing some medium- or large-sized mammals to enter the road corridor
Figure 54. The wildlife fencing continues above a box culvert for medium-sized mammals
Figure 55. Soil in corrugated metal culvert makes it more suitable for use by wildlife
Figure 56. A wildlife underpass with livestock fencing along U.S. Highway 93 in Montana
Figure 57. After construction, straw mats were used to protect slopes from erosion and rapid establishment of weeds along U.S. Highway 93 in Montana
Figure 58. Native shrubs and trees were planted at the approaches to crossing structures along U.S. Highway 93 in Montana
Figure 59. Red Earth Overpass on the Trans-Canada Highway in Banff National Park, Alberta
Figure 60. Schwarzgraben wildlife overpass across a two-lane road (B31) in southern Germany, where the area surrounding the overpass is higher than the road
Figure 61. This fence for amphibians and medium- and large-sized mammals connects well to the fence on the wildlife overpass "Waterloo" near the town "Roermond", The Netherlands. Note that the fence on the wildlife overpass also acts as a light and sound barrier
Figure 62. The wildlife overpass "Waterloo" with wildlife fencing across the A73 motorway near the town "Roermond", The Netherlands, consists of planks that also act as a light and sound barrier
Figure 63. The wildlife fencing on the wildlife overpass "Waterloo" across the A73 motorway near the town "Roermond", The Netherlands, consists of planks that also act as a light and sound barrier
Figure 64. The wildlife fencing on the wildlife overpass "Waterloo" across the A73 motorway near the town "Roermond", The Netherlands. Note that the concrete barrier prevents small animal species from falling off the overpass
Figure 65. Small trees, shrubs and grass vegetation on top of one of the overpasses along the Trans-Canada Highway in Banff National Park, Alberta
Figure 66. A row of tree stumps leading animals to and across the wildlife overpass "Waterloo" across the A73 motorway near the town "Roermond", The Netherlands
Figure 67. Newly planted shrubs (foreground) and a row of tree stumps on the De Borkeld wildlife overpass across the A1 motorway in The Netherlands
Figure 68. An artificial pond on the approach of the wildlife overpass "Waterloo" across the motorway A73, near the town "Roermond", The Netherlands
Figure 69. A rectangular and an hourglass-shaped wildlife overpass design
Figure 70. Structures built to pass water typically should be designed to avoid erosion and allow passage of aquatic species. The structure shown has no adaptations for terrestrial species and is also likely to be impassable for many aquatic species
Figure 71. Different walkway designs for small- and medium-sized mammals (e.g., up to marten and rabbit size) in box culverts (retrofitted or integrated design). A = minimum 0.5-0.7 m (1.6-2.3 ft), preferred 1m (3.3 ft), B= 0.6 m (2 ft)
Figure 72. Connection of walkway to adjacent bank
Figure 73. Wildlife underpass (large-mammal culvert) along U.S. Highway 93 in Montana with a ditch that allows water to flow (seasonally)
Figure 74. Wildlife underpass (over-span bridge) in combination with a creek crossing along U.S. Highway 93 in Montana
Figure 75. The same wildlife underpass as in figure 74 during spring runoff
Figure 76. Over-span bridge across a stream, with a bank and walkway for terrestrial large-mammal species along the Trans-Canada Highway, Banff National Park, Alberta
Figure 77. Concrete walkways for wildlife on both banks of a creek at an over-span bridge along U.S. Highway 93, south of Missoula, MT
Figure 78. Walkway cleared of large rocks, for people and large mammals, along State Highway 75 between Ketchum and Hailey, ID
Figure 79. Bridge across the Jocko River, along U.S. Highway 93 in Montana
Figure 80. An underpass designed for wildlife and human access, farm machinery and livestock along U.S. Highway 93, south of Missoula, MT
Figure 81. An underpass for a road (Lage Vuurscheweg) under the motorway A27 near the town "Hilversum", The Netherlands, that was modified with soil and tree stumps to encourage co-use by wildlife (target species included invertebrates, amphibians, reptiles, and small- and medium-sized mammals)
Figure 82. An underpass for a road (Hilversumsestraatweg) under the motorway A27 near the town "Hilversum", The Netherlands, that was modified with soil and tree stumps to encourage co-use by wildlife.
Figure 83. An underpass for a road (Hilversumsestraatweg) under the motorway A27 near the town "Hilversum", The Netherlands, that was modified with soil and tree stumps to encourage co-use by wildlife to the right of the fence. The purpose of the fence, which is painted black, is to reduce light and noise disturbance from traffic
Figure 84. Close-up of the fence, painted black, aimed at reducing light and sound disturbance from traffic
Figure 85. A row of tree stumps, grass-herb-shrub vegetation, and a road (road name: Ericaweg, overpass name: Wallenburg) on top of an overpass across the A28 motorway near the town "Zeist", The Netherlands. The overpass was originally designed for a road only
Figure 86. The same overpass as figure 85 showing the gentle grade of the concrete curb, which allows small animals to access the vegetated strip
Figure 87. Another view of the same overpass shows the black screen that was attached to the fence to reduce light disturbance from the A28 motorway
Figure 88. A row of tree stumps, grass-herb-shrub vegetation, and a road (overpass name: "Mauritskamp") on top of an overpass across the A28 motorway near the town Zeist, The Netherlands. The overpass was originally designed for a road only. Note the black screen attached to a chain link fence to reduce light disturbance from the A28 motorway
Figure 89. Road removed on bridge over motorway in Belgium and replaced with soil for vegetation and bike path
Figure 90. A bike/pedestrian bridge adjacent to the De Borkeld wildlife overpass (right) across the A1 motorway in The Netherlands
Figure 91. A wildlife overpass combined with a bike/pedestrian path in The Netherlands
Figure 92. An area-cover animal detection system (passive infrared, manufactured by ADPRO (Xtralis, USA)), designed to detect large mammals on both sides of the pole, at a WTI-MSU test facility near Lewistown, MT
Figure 93. An infrared break-the-beam animal detection system (manufactured by Calonder Energy, Switzerland) at a gap in a wildlife fence near the town 't Harde, The Netherlands
Figure 94. Activated warning signal and sign in Sequim, WA
Figure 95. Potential applications for animal detection systems
Figure 96. Recently cleared shrubs to improve driver visibility and to reduce browse for moose along the George Parks Highway (Hwy 3) in Alaska
Figure 97. Pronghorn eating roadside vegetation
Figure 98. Re-growth of cleared shrubs along the George Parks Highway (Hwy 3) in Alaska
Figure 99. Vegetation management in right-of-way may conflict with conservation interests
Figure 100. White-tailed deer can cause wildlife-human conflicts, including deer-vehicle collisions, especially in urban and suburban settings
Figure 101. Mitigations for threatened and endangered species as part of a strategy for reducing WVCs
Figure 102. A warning sign for American crocodiles along U.S. Highway 1 between Florida City and Key Largo, FL
Figure 103. A 1.83-m-high (6-ft-high) chain-link wildlife fence intended for American crocodile along U.S. Highway 1 between Florida City and Key Largo, FL
Figure 104. An underpass for American crocodiles along U.S. Highway 1 between Florida City and Key Largo, FL
Figure 105. A short section of fencing (30 m (100 ft) long, 90 cm (3 ft) high) aimed at directing American crocodiles to 1.8-m-wide (6-ft-wide) culverts along Highway 905A, just south of the Card Sound Bridge in Key Largo
Figure 106. Desert tortoise warning sign along an access road (no name) to the Hyundai Proving Grounds, near Mojave, Kern County, CA
Figure 107. Tortoise barrier fence erected along State Highway 58 near Kramer Junction, San Bernardino County, CA
Figure 108. Desert tortoise exiting a culvert retrofitted to allow tortoises to cross beneath State Highway 58 near Kramer Junction, San Bernardino County, CA
Figure 109. Fences lead gopher tortoises toward a culvert along Highway 63 in Green County, south of Leakesville, MS
Figure 110. Fences (76 cm (2.5 ft) high) keep Alabama red-bellied turtles from entering the roadway and lead them toward bridges where they can cross under the road safely along the Mobile Bay Causeway (US90/98), between Spanish Fort and Mobile, AL
Figure 111. Concrete barrier leads amphibians toward an underpass along the road "Hilversumsestraatweg" near the town Hilversum, The Netherlands
Figure 112. Plastic sheets that guide amphibians to an underpass, near the town Hilversum, The Netherlands
Figure 113. Plastic screens combined with a badger fence along the road "Hilversumsestraatweg" near the town Hilversum, The Netherlands
Figure 114. Plastic screens combined with a badger fence guiding the animals towards an underpass for amphibians under the road "Hilversumsestraatweg" near the town Hilversum, The Netherlands
Figure 115. Concrete barrier and planks guiding amphibians toward an underpass under the road "Bussumergrindweg", near the town Hilversum, The Netherlands
Figure 116. Plastic screens combined with a medium- and large-mammal fence guiding the animals toward an overpass (Waterloo) along the A73 motorway near the town Roermond, The Netherlands. Note that the screw that holds the two plastic sheets together is broken, allowing for a gap and potential intrusions of amphibians and other small species into the road corridor
Figure 117. Plastic screens combined with a medium- and large-mammal fence guiding the animals toward an overpass (Waterloo) along the A73 motorway near the town Roermond, The Netherlands. Note that two adjacent sheets have a gap that is covered by fine mesh wire fence to prevent amphibians and other small species from entering the road corridor
Figure 118. Plastic screens that collapsed were intended to guide amphibians toward an underpass near the town Hilversum, The Netherlands. The gap allows amphibians and other small species to enter the road corridor
Figure 119. The vegetation on both sides of a concrete barrier for amphibians was mowed to prevent small species from using the vegetation to climb the barrier and enter the road corridor, near the town Haywards Heath, West Sussex, England
Figure 120. Open tops for underpasses for amphibians are often recommended so that air, soil humidity and light conditions inside the tunnels are similar to conditions outside
Figure 121. The open concrete top of an underpass for amphibians, allowing light, air, and moisture to enter, near the town Hilversum, The Netherlands
Figure 122. The open metal top of an underpass for amphibians, allowing light, air, and moisture to enter, under the road "Hilversumsestraatweg" near the town Hilversum, The Netherlands
Figure 123. Close-up of an underpass for amphibians along the road "Hilversumsestraatweg" near the town Hilversum, The Netherlands. Note that the open roof allows light, air, and moisture to enter the underpass
Figure 124. A concrete barrier for amphibians and reptiles along U.S. Highway 441 through Paynes Prairie, south of Gainesville, FL
Figure 125. A concrete barrier combined with an underpass for amphibians and reptiles along U.S. Highway 441 through Paynes Prairie, south of Gainesville, FL
Figure 126. A closeup of the concrete barrier for amphibians and reptiles along U.S. Highway 441 through Paynes Prairie, south of Gainesville, FL
Figure 127. A gate that allows for access to a field with crops through an amphibian barrier, and a medium- and large-mammal fence, near wildlife overpass "Schinheuvel," near the town Roermond, The Netherlands. Note that the gate connects closely to a hard surface to prevent amphibians and other small species from entering the road corridor.
Figure 128. A gate for pedestrians through a badger fence and an amphibian barrier. Note that the gate has sheeting at the bottom to prevent amphibians and other small species from entering the road corridor. Note also that the gate is angled, so that gravity will automatically close the gate
Figure 129. The wildlife overpass "Groene Woud" in The Netherlands, with amphibian habitat
Figure 130. Guardrail painted black near amphibian tunnels and a multiple-use underpass, along the road "Hilversumsestraatweg", near the town Hilversum, The Netherlands. The painted guardrail is expected to reduce glare and light disturbance for amphibians and other species groups
Figure 131. Hawaiian goose warning sign in Volcanoes National Park, HI
Figure 132. Hawaiian goose warning sign in combination with advisory speed limit in Volcanoes National Park, HI
Figure 133. Hawaiian goose "no feeding" sign in Kokee State Park, Kauai, HI
Figure 134. Speed bump, specifically installed to reduce vehicle speed for nearby breeding, roosting and feeding area for the Hawaiian goose in Volcanoes National Park, HI
Figure 135. Poles across State Road A-1-A over the Sebastian Inlet in Florida
Figure 136. "Hop-over" for birds to encourage them to fly above traffic
Figure 137. Embankment for birds to encourage them to fly above the traffic on the A27 motorway near Huizen, The Netherlands. Embankments are on both sides of the road, and also serve to reduce sound and light disturbance into the open grasslands. Note that the yellow top of a freight truck shows just above the embankment
Figure 138. Warning signs for Key deer along the two-lane U.S. Highway 1 on Big Pine Key, FL
Figure 139. Signs showing the road mortality numbers of Key deer on a side road of U.S. Highway 1 on Big Pine Key
Figure 140. Warning sign for Key deer combined with message to not feed the deer along a side road of U.S. Highway 1 on Big Pine Key
Figure 141. Permanently flashing warning signs for Key deer along U.S. Highway 1 on Big Pine Key
Figure 142. A 1.8-m-high (6-ft-high) fence for Key deer along U.S. Highway 1 on Big Pine Key
Figure 143. The approach to an underpass for Key deer along U.S. Highway 1 on Big Pine Key
Figure 144. One of the two underpasses for Key deer along U.S. Highway 1 on Big Pine Key
Figure 145. Warning sign for the Florida panther along SR 29 in southern Florida
Figure 146. Warning sign for the Florida panther along SR 29 in southern Florida
Figure 147. Warning sign for the Florida panther along SR 29 in southern Florida
Figure 148. Warning sign for Florida panther in southern Florida
Figure 149. Warning signs for Florida panther along SR 29 in southern Florida
Figure 150. Permanently flashing warning sign for Florida panther, combined with a rumble strip along SR 29 in southern Florida
Figure 151. Wildlife fencing, with barbed wire overhang, for the Florida panther on SR 29 in southern Florida
Figure 152. Underpass for hydrology (water flow) and the Florida panther along Interstate 75 in southern Florida
Figure 153. Monitoring and evaluation as part of a strategy for reducing WVCs
Figure 154. Tracking bed, photo camera and DNA hair snag
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