ESA POSITION STATEMENT: The Arctic National Wildlife Refuge

The Arctic National Wildlife Refuge


The Arctic National Wildlife Refuge (ANWR) is an area rich in plants, animals, and commercial oil potential. The vast diversity of wildlife within ANWR includes more than 160 bird species, 36 kinds of land mammals, 9 marine mammal species, and 36 types of fish. ANWR is one of the least disturbed ecosystems on Earth, giving it global significance for scientific research and as part of Earth’s natural heritage.

ANWR is also thought to hold considerable reserves of oil and gas. It has been stated that the impacts of oil and gas exploration would be confined to a small portion of ANWR, an area of land on the coastal plain called the “1002 Area.” However, it is important to realize that the 1002 Area also comprises critical habitat of particular ecological importance for many wildlife species. The Ecological Society of America believes that oil and gas exploration will likely have long-term effects on ecosystem processes resulting in unanticipated and potentially detrimental effects on the region.


The land under consideration for oil exploration is known as the “1002 Area.” This section of the Refuge was specifically left as undetermined land, and authority was vested in Congress to decide whether or not to open it up for oil and gas drilling. The 1002 Area includes most of the Refuge’s coastal plain and Arctic foothills region, but comprises only 10 percent of the entire ANWR.

Assessments indicate that the coastal plain may contain substantial amounts of oil and gas. The exact impacts on the region’s relatively pristine ecosystems will depend upon the methods of oil exploration. It is likely that some of the problems that have occurred in the past such as oil spills, dumping of waste water, the building of large gravel roads and pads etc., can be reduced by modern methods of oil exploration. Other potential effects of exploration, however, include altering natural drainage patterns, depositing alkaline dust over a wide area, contaminating soil and water with fuel and oil from spills, and blocking, deflecting, or disturbing wildlife. It is unclear by how much the impact of development can be minimized.

Further complicating the picture is the geography of the 1002 Area itself. The region is located more than 30 miles from the end of the nearest pipeline and more than 50 miles from the nearest gravel road and oil support facilities. Also, unlike Prudhoe Bay where one giant oil field was found, it is more likely that the oil in the 1002 Area is spread out into many small accumulations. This would mean that development in the 1002 Area could require a large number of small production sites spread out across the Refuge landscape, widening the footprint of development on the region.

Development of the coastal plain’s petroleum resources could have serious impacts on the ecosystem of the region, in turn affecting numerous plant and animal species. Winter oil exploration is most likely to impact muskoxen, polar bears, and arctic tundra vegetation. If winter exploration is extended to other seasons, the breadth of potentially affected species grows to include caribou and birds that use the area for calving and nesting.

The potential effects of oil exploration on caribou, one of the region’s most abundant species, provide a detailed example of the possible impacts of exploration on the wildlife of ANWR. Potential impacts on the Porcupine Herd, which calves in the area proposed for exploration, include reducing the amount and quality of preferred forage habitat available during and after calving, restricting access to habitats where animals can find refuge from parasitic insects, and altering an ancient migratory pattern, the consequences of which are uncertain.

It is evident from the oil and gas exploration of nearby Prudhoe Bay that industrial activities affect the behavior of caribou. Prudhoe Bay data show that although the Central Arctic caribou herd has grown in numbers in areas with oil exploration, they have shifted their calving sites away from development. Proponents of drilling often point to the increase in the herd as evidence that oil exploration does not adversely impact animal populations. However, scientific data clearly demonstrate that the behavior of the herd has changed, and it is entirely possible that the population increases would have been even more pronounced without human intrusion.

The geographic conditions of the 1002 Area could exacerbate the effects of caribou behavior changes associated with oil exploration. The 1002 Area is much smaller than that of Prudhoe Bay, with mountains in closer proximity to the sea, leaving fewer places for displaced cows to go. If cows moved inland to avoid oil fields in the 1002 Area, they would end up in the foothills where predators are more abundant, further reducing calf survival rates. A reduction in annual calf survival of as little as 5 percent would be sufficient to cause a decline in the Porcupine caribou population.

Because the area in question is vital habitat to many native animal and plant species, the Ecological Society of America believes that drilling in the 1002 Area could produce unanticipated and possibly negative effects on the region.

Approved by the Governing Board of the Ecological Society of America, March 2002