BLM-AK, Monitoring Movements and Distribution of the Teshekpuk Caribou Herd

The Teshekpuk caribou herd (TCH) calves and summers in the National Petroleum Reserve in Alaska (NPRA, managed by the BLM) on Alaskas North Slope. The TCH is the most important caribou herd for subsistence in villages within the NPRA, but it is currently in a steep population decline. This will have significant adverse impacts on the social well-being of many NPRA residents. We need to continually update our knowledge of TCH range use in order to best manage this important population and to prevent any adverse consequences to the herd from BLMs management of oil and gas resources in the NPRA. Our need to estimate abundance, population trajectory and estimate harvestable surplus is critical at this time. A statistically robust sample of collared individuals is needed to monitor herd demographics. The TCH survey and inventory program is based on collaring young individuals with VHF collars, and beginning to replace those collars at 3-4 years of age, when most caribou in this herd become reproductive. This program allows for a known-aged sample of caribou, and the ability to follow most individuals from 12 months of age (or 2-3 days of age in some cases) until death, providing a great deal of information on age-specific fecundity, recruitment and mortality. Utilizing satellite collars allows us to accurately and quickly identify when and where individuals die, adding to our ability to investigate sources of mortality, and to better utilize costly flight resources when conducting focal animal sampling (i.e. parturition, composition and recruitment surveys). Additionally, a large sample of satellite collared bulls allows us to better approximate herd distribution and demography during extensive periods of the year when the degree of sexual segregation is high. Having a large sample of satellite collared individuals is also essential for monitoring herd mixture, and thereby estimating herd-specific harvest during times and in areas with multiple herds.