Monitoring protocol for the Denali caribou herd, Denali National Park and Preserve, Alaska: Central Alaska Inventory and Monitoring Program
Adams LG and Meier TJ. 2018. Monitoring protocol for the Denali caribou herd, Denali National Park and Preserve, Alaska: Central Alaska Inventory and Monitoring Program. Natural Resource Report. NPS/CAKN/NRR—2018/1754. National Park Service. Fort Collins, Colorado
Caribou research methods developed over the last 25 years at DENA serve as the basis for this monitoring protocol. Our approach involves monitoring a large sample (> 50 individuals) of radiocollared adult females that is representative of the herd’s age structure to assess their productivity and survival, and to facilitate conducting annual censuses and age/sex composition surveys. Caribou are captured via helicopter darting; instrumented with radiocollars; weighed, measured, and blood-sampled; and then released. We have standardized methods for estimating herd size each year based on an estimate of cow numbers in early June, obtained via helicopter surveys and corrected for sighting bias relative to group size, and extrapolation of that estimate to a fall herd size using summer survival rates of radiocollared females and fall age/sex composition ratios. All radioed females ≥ 2 years old are located by helicopter in mid-May to determine their reproductive status via observation of a calf at heel, retained hard antlers, or a distended udder (Whitten 1995), in order to assess annual herd productivity and age-specific productivity. Standardized helicopter surveys in late September provide information on calf recruitment to fall and adult sex ratios. Caribou are radiolocated approximately 8 times a year to determine survivorship and seasonal distribution patterns, and to facilitate other surveys.
- Type
- Published Report
- Authors
- Adams, Layne; Meier, Thomas
- Date of Issue
- 2018-09
- Publisher
- National Park Service
- Units
- CAKN , DENA , NRSS