Western Arctic Herd Caribou Use of the Proposed Arctic Mine Footprint and Surrounding Area, 2010–2024
Joly K and Cameron MD. 2026. Western Arctic Herd Caribou Use of the Proposed Arctic Mine Footprint and Surrounding Area, 2010–2024. Science Report. NPS/SR—2026/455. National Park Service. Fort Collins, Colorado. https://doi.org/10.36967/2318566
A mine, known as the Arctic Mine, has been proposed in the Ambler Mining District north of the village of Kobuk, Alaska. A proposed 211-mile-long industrial road (the Ambler Road) would connect the area and the Arctic Mine to the contiguous continental road system. We documented the use of the area around the proposed Arctic Mine and connecting road by GPS-collared, adult female Western Arctic Herd (WAH) caribou (Rangifer tarandus) from 2010 to 2024 prior to development to provide baseline data. The winter season exhibited the greatest use, followed by fall and then spring, for both the percentage of collared caribou with relocations in and movement vectors intersecting the areas around the proposed mine. Use was quite variable by year and season, ranging from 0–81% of the collared caribou using the area around the proposed mine in any given season. The percent of collared caribou using the Southern Area (the proposed road connecting the Kobuk village-Bornite Mine to the proposed Ambler Road) was generally greater than the percent of collared caribou using the Northern Area (the road north of the proposed Ambler Road leading to the proposed mine area). Summer use was negligible, with a single caribou in the area during August 2010 but none in any other year. Proportion of time spent near the proposed mine was also quite variable. Caribou spent the greatest proportion of time near the proposed mine in winter, with averages reaching as high as 100% of this season in one year. Fall had the next greatest proportion of time used with averages reaching 56% of the season near the proposed mine. Spring averages reached 39% of the season near the proposed mine. In some years, the percent of time spent near the proposed mine was <1%. Caribou migrations are quite variable with use of winter ranges exhibiting the greatest variability. Caribou use of the area around the proposed Arctic Mine reflects this variability. In many years, depending on the buffer size analyzed, no caribou used the area near the proposed mine. However, given that a 35-km buffer around either the proposed mine’s Northern Area or Southern Area footprint represents only about 1% of the herd’s range, having up to 76–81% of collared caribou in these areas, respectively, reveals that this region can have a high percentage of WAH caribou present in some years, especially during winter.
- Type
- Published Report
- Authors
- Joly, Kyle; Cameron, Matthew
- Date of Issue
- 2026-07
- Publisher
- National Park Service
- DOI
- 10.36967/2318566
- Units
- ARCN , NRSS
- Keywords
- ARCN, Arctic Mine, Arctic Network, Caribou, collar, Distribution, Geographic Positioning System, GPS, Herd, inventory and monitoring program, Mammal, Monitor, National Park, National Park Service, Northwest Alaska, Rangifer tarandus, Satellite, WAH, Western Arctic Herd