Rapid population increase in an introduced muskox population, West Greenland

Abstract

In 1962 and 1965, 27 (13 and 14) muskox yearlings were translocated from East Greenland (71°N) to the Angujaartorfiup Nunaa range in West Greenland (67°N). Angujaartorfiup Nunaa is a 6600 km2 icefree, continental area where caribou are indigenous. The climate is strictly continental with a minimum of precipitation but with abundant vegetation. Aerial surveys in 1990 documented that the muskox population has increased to 2600 heads despite quota-based harvesting since 1988. The annual quota was 200, 300 and 400 for 1988, 1989 and 1990, respectively. Distribution of muskoxen shows a significant preference for low altitude habitats southeast of Kangerlussuaq Airport and around Arnangarnup Qoorua (Paradise valley). Annual population increment averages 30% and the calf crop is around 24% of the population. Yearling recruitment in the population reveals that calf mortality during winter is very limited. About half of the 1-year-old females are served and they eventually give birth to their first calf when they turn 2 years old. With half of the 2-year-old females reproducing, the calf/cow ration ranges between 0.9 and 1.0

Population structure and dynamics in captive muskoxen at the Large Animal Research Station, 1988-1994

“…Over the 7 year period, calf production per HP cow was 0.94. This was similar to estimates from expanding and reintroduced populations in the wild; Banks Island, 0.83 (Latour, 1987), West Greenland, 0.90-1.0 (Olesen, 1993), Nunivak Island, 0.80 (Smith, 1984) Northern Quebec, 0.86¬ 0.97 (Le Henaff & Crete, 1989) and Northeast Alaska, 0.89 (Jingfors & Klein, 1982). Calf production among the LP cows was 0.60, consistent with estimates from less productive populations; NE Gteenland, 0.39-0.57 (Thing et al, 1987) and 0.58-0.63 (Lassen, 1984).…”

Capital and income breeding traits differentiate trophic match–mismatch dynamics in large herbivores

“…There was no correlation between the annual timing of vegetation emergence and caribou calving (Pearson's r ¼ 0.23, p ¼ 0.50; figure 2b). The midpoint of the local muskox calving season occurs in late April [31,54], prior to the onset of our field season and approximately six weeks before peak green-up (figure 2a). We therefore provide only a depiction of the duration of the muskox calving season (figure 2a) and an estimate of 13 May (day of year 133) as a conservative end-of-calving date on the basis of a literature review [31,34,46,54,55] to provide comparative trophic context to the calving phenology of each herbivore population.…”

Calf Production, Calf Survival, and Recruitment of Muskoxen on Banks Island during a Period of Changing Population Density from 1986-99

“…Le Hénaff and Crête (1989) reported high calf production during a 3-year period when an introduced population of muskoxen in Quebec showed a rapid increase in population. Olesen (1993) estimated that half of the 2-year-old females reproduced in a rapidly increasing population of muskoxen in West Greenland.…”

“…Historical declines have been attributed to overexploitation by humans and severe weather (Barr, 1991;Reynolds, 1998), but the data needed to address these factors critically are lacking. Most population studies of muskoxen have been limited to descriptions of either current status (Case et al, 1989;Smith, 1989;Yakushkin, 1989;Boertmann et al, 1992;Gunn, 1995) or changes in population numbers, providing little additional demographic data (Le Hénaff and Crête, 1989;Gunn et al, 1991;Olesen, 1993). Extended time series of population data for muskoxen are limited (Reynolds, 1998).…”

“…Re-established and introduced populations have increased in Quebec (Le Hénaff and Crête, 1989), Alaska (Reynolds, 1998), West Greenland (Olesen, 1993), and Russia (Yakushkin, 1989). Indigenous populations in Greenland (Boertmann et al, 1992) and in the Northwest Territories have also increased (Barr, 1991;Nagy et al, 1996).…”