Caribou Management and Research

Publications & Reports

Research

In the 1970s people were concerned about the effect of the trans-Alaska oil pipeline, expanding oil development, and increased disturbance from use of aircraft and snowmobiles on caribou. Although there was some displacement of caribou calving in the Prudhoe Bay oilfield, in general, caribou have not been adversely affected by human activities in Alaska. Pipelines and most other developments are built to allow for caribou movements, and caribou have shown us that they can adapt to the presence of people and machines. As human activities expand in Alaska, the great challenge for caribou management is for man to consider the needs of our caribou herds and ensure that they remain a visible, healthy part of our landscape.

Research Projects

Project Information

Development of methods to assess effects of oil field infrastructure on caribou movements, growth, and survival

Project 3.49, Federal Aid in Wildlife Restoration Grant. Project Duration: July 1 2006-June 30, 2010. Principal Investigator: Stephen Arthur, Fairbanks.

This project will complete collection of data concerning movements, growth rates, and survival of caribou from the Central Arctic herd in relation to the oil field complex near Prudhoe Bay, Alaska. Data collection for this work began in 2001 as part of project 3.46. In addition, this project will support a graduate student in mathematical ecology, who will develop new methods of modeling movements of animals using data collected using GPS radio collars. These models will then be used to assess potential effects of anthropogenic disturbance on movements and habitat use of caribou, and how changes in caribou behavior due to disturbance may affect growth and survival of caribou calves.

In FY07, 59 caribou cows (=3 years old) were located during 1–7 June 2007. Of these, 39 were pregnant and 16 were accompanied by calves. Parturition rate was 93%. Fifty-seven cows were located on 21–22 June, of which 46 (81%) were accompanied by calves. Of 34 calves that had been radiocollared during early June 2006, 32 were alive in July and were monitored through early June 2007 to estimate survival rates. These included 15 from the eastern calving area and 17 from the western calving area (calving areas were either east or west of the Sagavanirktok River). During summer 2006, no calves from the eastern area died, whereas survival for western calves was 88%. Annual survival rates for the eastern and western calving areas were 0.70 and 0.43, respectively.

Thirty radiocollared calves were captured by net-gunning in September and 18 were captured in March 2007. Location data collected during previous years were entered into a geographic information system and compared to a digital land cover map. Twenty-eight caribou cows equipped with GPS collars were monitored from June 2006 to March 2007. Twenty-four of these were captured by net-gun during March 2007 and their collars removed. The remaining 4 collars were recovered on 3 July 2007 after the programmed release mechanisms caused the collars to fall off the caribou. Data were downloaded from the collars and will be analyzed to assess movement patterns. Wintering distribution was assessed by radiotracking cows and calves during March 2007. Fifty-eight cows and 26 calves were located. The greatest concentrations of collared caribou were in Gates of the Arctic National Park, south of the crest of the Brooks Range, or along the northwestern boundary of the Arctic National Wildlife Refuge, in the northern foothills of the Brooks Range. Some additional caribou were in the Middle Fork Chandalar River and the Wind River.

A photo census was not conducted due to failure of the herd to aggregate.

An interim progress report was prepared and distributed to cooperators and other interested individuals. In addition, presentations were made at the annual meeting of The Wildlife Society in September 2006 and at the North Slope Science Initiative caribou workshop in February 2007.