Demography of the Porcupine caribou herd, 1983-1992
Fancy SG, Whitten KR, Russell DE. 1994. Demography of the Porcupine caribou herd, 1983-1992. Canadian Journal of Zoology. 72(5):840-846
Population size, parturition rates, and sex- and age-specific survival rates were determined for the Porcupine caribou herd (Rangifer tarandus granti) in northeastern Alaska and northwestern Canada between 1983 and 1992. The herd increased at an annual rate of r = 0.0467 between censuses in July 1983 (n = 135,000), July 1987 (n = 165,000), and July 1989 (n = 178 000). The mean parturition rate for 225 radio-collared cows aged _3 years monitored for 603 reproductive attempts between 1982 and 1992 was 80% and did not differ among years. First-year survival of calves was 51%. The survival rate of calves through their first month differed among years (range 57-90%). The mean annual survival rate for _3-year-old caribou was 84.2% for 225 females and 82.6% for 42 males. Hunting mortality for the herd averaged 2-3% annually. Population estimates generated by a computer model using parturition and survival rates for the herd closely tracked population trends determined from photocensus data. Growth of the herd is most sensitive to the survival of females 3 years of age and older, followed by calve production and survival.
- Type
- Journal Article
- Authors
- Fancy, Steven; Whitten, Kenneth; Russell, Donald
- Units
- ARCN , CAKN , GAAR , YUCH
- Keywords
- Abundance, Arctic National Wildlife Refuge, Caribou, Central Arctic Caribou Herd, Deer, Mammals, Mortality, North Slope, Population Ecology, Population regulation, Population Trends, Porcupine Caribou Herd, producitivity, radio collars, Reproduction, Survival, Ungulates, Yukon Territory