Down the Wrong Road: Roads and Alaska
This paper reviews recent research on the impacts of roads on wildlife in Alaska. This research has largely focused on caribou in relation to oil and gas infrastructure, including roads, but some has considered effects on other wildlife. The exemption of the Tongass and Chugach National Forests from roadless rule protection and the increase of RS 2477 claims will also be explored, as these two policy developments have the potential to greatly increase road development and its effects on wildlife in Alaska.
Caribou
The vast majority of road research in Alaska deals with caribou. Most studies measure caribou density, avoidance, habitat loss, and movement in relation to the oil infrastructure of the Prudhoe Bay region. Females appear to be especially influenced by roads and development.
Caribou density is highly affected by the presence of roads. One study found caribou density decreased by 63% with a road density of just 0.3 km/km2 and further declined by 86% when road densities increased to 0.6-0.9 km/km2. Although caribou density decreased as road density increased, road construction itself caused the greatest impacts to caribou density. Impacts were especially apparent with female calf pairs (Nelleman and Cameron 1998).
Whitten and Cameron (1983) found the Prudhoe Bay oil field, including nearby roads, presented a barrier to caribou movement. This barrier is again more significant for female caribou. Cameron (1983) also found calving females are highly intolerant to disturbance and will abandon areas with development or disturbance — females were found to avoid areas within 4 km of roads. Additionally, roads were often built in areas of optimal habitat and resulted in nutrient deficiency, habitat loss, and lower productivity for the overall herd (Cameron 1983; Nelleman and Cameron 1998).
The combination of roads and oil pipelines also had a major effect on caribou movement. When these two structures were present, caribou crossings were significantly less than expected. Avoiding these structures could increase energy expenditure and lower productivity for the herd. Again, female caribou were especially likely to avoid roads and oil pipelines (Murphy and Curatolo 1986; Curatolo and Murphy 1986).
A few studies contradict those cited above (Cronin et al. 1998; Yost and Wright 2001; Burson et al. 2000). In these studies, in Denali National Park and Prudhoe Bay, development and roads appeared unrelated to caribou distribution or behavior. Although there is no unanimous conclusion, the majority of the research suggests that roads have a negative impact, specifically on female caribou and overall caribou movements. Any negative effect on female movement is particularly important because it potentially reduces the herd’s reproductive capability.
Other Wildlife
Research on road impacts on Alaskan wildlife other than caribou is more limited. Moose distribution in Denali was found to be less than expected in areas close to park roads (Yost and Wright 2001; Burson et al. 2000). Dall sheep, however, were not found to be as impacted within the park (Dalle-Molle and Van Horn 1991; Burson et al 2000).
Herds inside Denali were found to have much less difficulty crossing roads than those outside the park — this may be due to habituation. While most sheep eventually crossed roads, they were often delayed and exposed to increased risks of both predation and vehicle collisions. Delays in traveling to summer habitat can place additional stress on winter range to provide the food needed by the herd, and can ultimately lead to decreased productivity of the herd (Dalle-Molle and Van Horn 1991; Burson et al. 2000). While the research on bears and roads in Alaska is limited, a wide range of bear studies in other areas found an increased mortality associated with roads, and an avoidance of roads with human activity (e.g. Robbins 2003; Gibeau et al. 2002; Benn and Herrero 2002). These negative impacts are likely to extend to Alaskan grizzly bears. One study in Denali National Park did find grizzly bears near roads more often than in previous years (Burson et al. 2000), but this was again explained by habituation. Wolves were studied in south-central Alaska and were found to frequent roads with little human presence, but they avoided areas that were used by humans (Thurber et al. 1994). Lynx showed little fear of roads in the same region, but by using roads they are threatened by increased human caused mortality (Bailey and Winthrop 1999).
Dust
Roads in Alaska cause many other ecological problems that affect wildlife as well. Alaska maintains 2000 miles of gravel roads, 66% of its total. Driving on these roads can release large amounts of dust, especially on windy days. Although dust appears to be a small, localized issue, the impacts can be profound — dust can affect vegetation, soils, ground ice, and wildlife (Walker and Everett 1987).
Many of the impacts of dust in relation to wildlife occur because of increased snow melt adjacent to roads (Foreman et al. 2003, Auerbach et al. 1997). Early snow melt leads to an increase in the concentration of waterfowl, ptarmigan, and their predators near roads. Some bird species return early from migration because of early snow melt. Caribou, grizzly bears, and raptors also use roadsides for foraging and hunting. This concentration of species near roads has led to increased vehicle-caused mortality, lack of a sufficient food source, and other problems mentioned above (Walker and Everett 1987).
Off-Road Vehicles
Established roads have been the focus to this point, but it is important to understand the role roads play as a “staging site” for off-road vehicles (ORVs; Sparrow et al. 1978). Much of Alaska’s road construction is related to oil and gas development, which is generally concentrated in the northern Alaska tundra. Tundra is such a sensitive ecotype that ORV impacts can remain for decades and often increase over time. ORV tracks can also assist the spread of invasive species, change the soil morphology, increase soil compaction, and cause plant damage (Sparrow et al. 1978).
Policies
Developments surrounding the Roadless Rule and RS 2477 may increase the number of roads in Alaska and hence increase their impacts on wildlife. The Roadless Rule, issued by the Clinton Administration in 1999, would have protected 58.5 million acres of public land from road development (USDA Forest Service 1997). The Bush administration, however, immediately took action against the rule and exempted Alaska’s Tongass and Chugach National Forests. These areas are now threatened with increased road construction.The 1872 Mining Law allowed RS 2477 right-of-way claims for the construction of roads on public lands. While new claims were prohibited after 1976, there has been a resurgence of county and state claims for roads built before that date. These claims could lead to increased access, development and ORV use on public lands.
Conclusion
Alaska is one of the last great refuges for wildlife, and while many people take for granted its abundance, wildlife still face the threats of development and roads. Exempting the Tongass and Chugach National Forests from the Roadless Rule, along with RS 2477 claims, could lead to increased road building, ORV access, logging, poaching, fragmented habitat, vehicle mortality, and other ecological problems associated with roads. Based on the conclusions of the research above, these policy developments are clearly going down the wrong road.
Literature Cited
Auerbach, N.A., Walker, M.D., Walker, D.A. (1997). The Effects of Roadside Disturbance on Substrate and Vegetation Properties in Arctic Tundra. Ecological Applications. 7(1): 218-235.
Bailey, T.N. and Wintrop, W.R. (1999). Lynx and development on the Kenai Pennisula, Alaska. Intermountain Journal of Sciences. 5(1-4): 41-42.
Benn, B., and Herrero, S. (2002). Grizzly bear mortality and human access in Banff and Yoho National Parks, 1971-98. Urus. 13: 213-221.
Burson, S.L., Belant, J.L., Fortier, K.A., Tomkiewicz, W.C. (2000). The effect of vehicle on wildlife in Denali National Park. Arctic. 53(2). 146-151.
Cameron, R.D. (1983). Issue: Caribou and petroleum development in arctic Alaska. Arctic. 36(3): 227-231.
Cronin, M.A., Amstrup, S.C., Durner, G.M., Noel, L.E., McDonald, T.L. and Ballard, W.B. (1998). Caribou distribution during the post-calving period in relation to infrastructure in the Prudhoe Bay oil field, Alaska. Arctic. 52(2): 85-93.
Curalto, J.A. and Murphy, S.M. (1986). The effects of pipelines, roads, and traffic on the movements of caribou. Canadian Field-Naturalist. 100(2): 218-224.
Dalle-Molle, J., and Vanhorn, J. 1989. Bear-people conflict management in Denali National Park, Alaska. In: Bromley, M., ed. Bear-people conflicts: Proceedings of a Symposium on Management Strategies. Yellowknife, Northwest Territories: Department of Renewable Resources. 121-128.
Forman, R.T. Sperling, D., Bissonette, J.A., Clevenger, A.P., Cutshall, C.D., Dale, V.H., Fahrig, L. et al. 2003. Road Ecology: Science and Solutions. Washington: Island Press.
Gibeau M.L., Clevenger A.P.; Herrero S.; Wierzchowski J. (2002) Biological Conservation. 103(2): 227-236.
Murphy, S.M., and Curatolo, J.A. (1986). Activity budgets and movement rates of caribou encountering pipelines, roads, and traffic in northern Alaska. Canadian Journal of Zoology. 65: 2483-2490.
National Park Service Memo (1993) available at: http://www.highway-robbery.org/lands/alaska.htm.
Nelleman, C., and Cameron R.D. (1996). Effects of development on terrain preference for calving caribou. Arctic. 49(1): 23-28.
Nie, M. (2004). Administrative rulemaking and public land conflict: The Forest Service’s roadless rule. Unpublished manuscript in press.
Robbins, E. (2003). How did the grizzly cross the road? Sierra, 88(3); at http://www.sierraclub.org/sierra/200307/wildlifecrossing.asp
Sparrow, S.D., Wooding, F.J., and Whiting, E.H. (1978). Effects of off-road vehicle traffic on soils and vegetation in the Denali Highway region of Alaska. Journal of Soil and Water Conservation. Jan-Feb. 20-27.
Thurber, J.M, Peterson, R.O., Drummer, T.D., Thomas, S.A. (1994). Gray wolf response to refuge boundaries and roads in Alaska. Wildlife Society Bulletin. 22: 61-68.
USDA Forest Service, Tongass National Forest Land and Resource Management Plan (1997).
Walker, D.A. and Everett, K.R. (1987). Road dust and its Environmental Impact on Alaskan Taiga and Tundra. Arctic and Alpine Research. 19 (4): 479-489.
Whitten, K.R., Cameron, R.D (1983). Movement of collared caribou, Rangifer tarandus, in relation to petroleum development on the Arctic slope of Alaska. The Canadian Field-Naturalist. 97(2): 143-146.
Yost, A.C. and Wright, R.G. (2001). Moose, Caribou, and Grizzly Bear Distribution in relation to road traffic in Denali National Park, Alaska. Arctic. 54(1): 41-55.
Caribou
The vast majority of road research in Alaska deals with caribou. Most studies measure caribou density, avoidance, habitat loss, and movement in relation to the oil infrastructure of the Prudhoe Bay region. Females appear to be especially influenced by roads and development.
Caribou density is highly affected by the presence of roads. One study found caribou density decreased by 63% with a road density of just 0.3 km/km2 and further declined by 86% when road densities increased to 0.6-0.9 km/km2. Although caribou density decreased as road density increased, road construction itself caused the greatest impacts to caribou density. Impacts were especially apparent with female calf pairs (Nelleman and Cameron 1998).
Whitten and Cameron (1983) found the Prudhoe Bay oil field, including nearby roads, presented a barrier to caribou movement. This barrier is again more significant for female caribou. Cameron (1983) also found calving females are highly intolerant to disturbance and will abandon areas with development or disturbance — females were found to avoid areas within 4 km of roads. Additionally, roads were often built in areas of optimal habitat and resulted in nutrient deficiency, habitat loss, and lower productivity for the overall herd (Cameron 1983; Nelleman and Cameron 1998).
The combination of roads and oil pipelines also had a major effect on caribou movement. When these two structures were present, caribou crossings were significantly less than expected. Avoiding these structures could increase energy expenditure and lower productivity for the herd. Again, female caribou were especially likely to avoid roads and oil pipelines (Murphy and Curatolo 1986; Curatolo and Murphy 1986).
A few studies contradict those cited above (Cronin et al. 1998; Yost and Wright 2001; Burson et al. 2000). In these studies, in Denali National Park and Prudhoe Bay, development and roads appeared unrelated to caribou distribution or behavior. Although there is no unanimous conclusion, the majority of the research suggests that roads have a negative impact, specifically on female caribou and overall caribou movements. Any negative effect on female movement is particularly important because it potentially reduces the herd’s reproductive capability.
Other Wildlife
Research on road impacts on Alaskan wildlife other than caribou is more limited. Moose distribution in Denali was found to be less than expected in areas close to park roads (Yost and Wright 2001; Burson et al. 2000). Dall sheep, however, were not found to be as impacted within the park (Dalle-Molle and Van Horn 1991; Burson et al 2000).
Herds inside Denali were found to have much less difficulty crossing roads than those outside the park — this may be due to habituation. While most sheep eventually crossed roads, they were often delayed and exposed to increased risks of both predation and vehicle collisions. Delays in traveling to summer habitat can place additional stress on winter range to provide the food needed by the herd, and can ultimately lead to decreased productivity of the herd (Dalle-Molle and Van Horn 1991; Burson et al. 2000). While the research on bears and roads in Alaska is limited, a wide range of bear studies in other areas found an increased mortality associated with roads, and an avoidance of roads with human activity (e.g. Robbins 2003; Gibeau et al. 2002; Benn and Herrero 2002). These negative impacts are likely to extend to Alaskan grizzly bears. One study in Denali National Park did find grizzly bears near roads more often than in previous years (Burson et al. 2000), but this was again explained by habituation. Wolves were studied in south-central Alaska and were found to frequent roads with little human presence, but they avoided areas that were used by humans (Thurber et al. 1994). Lynx showed little fear of roads in the same region, but by using roads they are threatened by increased human caused mortality (Bailey and Winthrop 1999).
Dust
Roads in Alaska cause many other ecological problems that affect wildlife as well. Alaska maintains 2000 miles of gravel roads, 66% of its total. Driving on these roads can release large amounts of dust, especially on windy days. Although dust appears to be a small, localized issue, the impacts can be profound — dust can affect vegetation, soils, ground ice, and wildlife (Walker and Everett 1987).
Many of the impacts of dust in relation to wildlife occur because of increased snow melt adjacent to roads (Foreman et al. 2003, Auerbach et al. 1997). Early snow melt leads to an increase in the concentration of waterfowl, ptarmigan, and their predators near roads. Some bird species return early from migration because of early snow melt. Caribou, grizzly bears, and raptors also use roadsides for foraging and hunting. This concentration of species near roads has led to increased vehicle-caused mortality, lack of a sufficient food source, and other problems mentioned above (Walker and Everett 1987).
Off-Road Vehicles
Established roads have been the focus to this point, but it is important to understand the role roads play as a “staging site” for off-road vehicles (ORVs; Sparrow et al. 1978). Much of Alaska’s road construction is related to oil and gas development, which is generally concentrated in the northern Alaska tundra. Tundra is such a sensitive ecotype that ORV impacts can remain for decades and often increase over time. ORV tracks can also assist the spread of invasive species, change the soil morphology, increase soil compaction, and cause plant damage (Sparrow et al. 1978).
Policies
Developments surrounding the Roadless Rule and RS 2477 may increase the number of roads in Alaska and hence increase their impacts on wildlife. The Roadless Rule, issued by the Clinton Administration in 1999, would have protected 58.5 million acres of public land from road development (USDA Forest Service 1997). The Bush administration, however, immediately took action against the rule and exempted Alaska’s Tongass and Chugach National Forests. These areas are now threatened with increased road construction.The 1872 Mining Law allowed RS 2477 right-of-way claims for the construction of roads on public lands. While new claims were prohibited after 1976, there has been a resurgence of county and state claims for roads built before that date. These claims could lead to increased access, development and ORV use on public lands.
Conclusion
Alaska is one of the last great refuges for wildlife, and while many people take for granted its abundance, wildlife still face the threats of development and roads. Exempting the Tongass and Chugach National Forests from the Roadless Rule, along with RS 2477 claims, could lead to increased road building, ORV access, logging, poaching, fragmented habitat, vehicle mortality, and other ecological problems associated with roads. Based on the conclusions of the research above, these policy developments are clearly going down the wrong road.
Literature Cited
Auerbach, N.A., Walker, M.D., Walker, D.A. (1997). The Effects of Roadside Disturbance on Substrate and Vegetation Properties in Arctic Tundra. Ecological Applications. 7(1): 218-235.
Bailey, T.N. and Wintrop, W.R. (1999). Lynx and development on the Kenai Pennisula, Alaska. Intermountain Journal of Sciences. 5(1-4): 41-42.
Benn, B., and Herrero, S. (2002). Grizzly bear mortality and human access in Banff and Yoho National Parks, 1971-98. Urus. 13: 213-221.
Burson, S.L., Belant, J.L., Fortier, K.A., Tomkiewicz, W.C. (2000). The effect of vehicle on wildlife in Denali National Park. Arctic. 53(2). 146-151.
Cameron, R.D. (1983). Issue: Caribou and petroleum development in arctic Alaska. Arctic. 36(3): 227-231.
Cronin, M.A., Amstrup, S.C., Durner, G.M., Noel, L.E., McDonald, T.L. and Ballard, W.B. (1998). Caribou distribution during the post-calving period in relation to infrastructure in the Prudhoe Bay oil field, Alaska. Arctic. 52(2): 85-93.
Curalto, J.A. and Murphy, S.M. (1986). The effects of pipelines, roads, and traffic on the movements of caribou. Canadian Field-Naturalist. 100(2): 218-224.
Dalle-Molle, J., and Vanhorn, J. 1989. Bear-people conflict management in Denali National Park, Alaska. In: Bromley, M., ed. Bear-people conflicts: Proceedings of a Symposium on Management Strategies. Yellowknife, Northwest Territories: Department of Renewable Resources. 121-128.
Forman, R.T. Sperling, D., Bissonette, J.A., Clevenger, A.P., Cutshall, C.D., Dale, V.H., Fahrig, L. et al. 2003. Road Ecology: Science and Solutions. Washington: Island Press.
Gibeau M.L., Clevenger A.P.; Herrero S.; Wierzchowski J. (2002) Biological Conservation. 103(2): 227-236.
Murphy, S.M., and Curatolo, J.A. (1986). Activity budgets and movement rates of caribou encountering pipelines, roads, and traffic in northern Alaska. Canadian Journal of Zoology. 65: 2483-2490.
National Park Service Memo (1993) available at: http://www.highway-robbery.org/lands/alaska.htm.
Nelleman, C., and Cameron R.D. (1996). Effects of development on terrain preference for calving caribou. Arctic. 49(1): 23-28.
Nie, M. (2004). Administrative rulemaking and public land conflict: The Forest Service’s roadless rule. Unpublished manuscript in press.
Robbins, E. (2003). How did the grizzly cross the road? Sierra, 88(3); at http://www.sierraclub.org/sierra/200307/wildlifecrossing.asp
Sparrow, S.D., Wooding, F.J., and Whiting, E.H. (1978). Effects of off-road vehicle traffic on soils and vegetation in the Denali Highway region of Alaska. Journal of Soil and Water Conservation. Jan-Feb. 20-27.
Thurber, J.M, Peterson, R.O., Drummer, T.D., Thomas, S.A. (1994). Gray wolf response to refuge boundaries and roads in Alaska. Wildlife Society Bulletin. 22: 61-68.
USDA Forest Service, Tongass National Forest Land and Resource Management Plan (1997).
Walker, D.A. and Everett, K.R. (1987). Road dust and its Environmental Impact on Alaskan Taiga and Tundra. Arctic and Alpine Research. 19 (4): 479-489.
Whitten, K.R., Cameron, R.D (1983). Movement of collared caribou, Rangifer tarandus, in relation to petroleum development on the Arctic slope of Alaska. The Canadian Field-Naturalist. 97(2): 143-146.
Yost, A.C. and Wright, R.G. (2001). Moose, Caribou, and Grizzly Bear Distribution in relation to road traffic in Denali National Park, Alaska. Arctic. 54(1): 41-55.