Seasonal Activity Budgets and Movements of a Reintroduced Alaskan Muskox Herd

Abstract

Daily activity budgets and group movement rates were recorded on a seasonal basis during 1978-80 for a reintroduced muskox (Ovibos moschatus) herd in arctic Alaska. Muskoxen spent more time lying than in any other activity. Resting periods in early and late winter and during calving were longer (P < 0.05) than during other seasons. Seasonal movements of the herd were limited. The lowest movement rates (x = 0.66 km/day) were during calving and the highest (t = 9.9 km/day) during periods of severe insect harassment. The localized movements of this herd should be considered when trying to minimize the potential impacts of oil exploratory and developmental activities within the Arctic National Wildlife Refuge. J. WILDL. MANAGE. 46(2):344-350 The muskox has adapted to year-round life in harsh arctic tundra regions. Seasonality of the arctic environment in combination with seasonal changes in animal requirements for energy and nutrients strongly influences muskox range relationships and grazing behavior. Critical to an understanding of grazing behavior are quantitative observations of daily activity budgets and movement rates. When combined with information on forage selection, digestion, and intake rates, these observations can be interpreted with respect to feeding strategies available to individual animals and correlated with seasonal range characteristics (White et al. 1981). Muskoxen exhibit an activity pattern characterized by regular alternations of activity and resting periods. The duration of such periods in other ruminants has been related to the quality and availability of forage (Arnold 1964, Campbell et al. 1969) and the periodicity has been used for comparing summer ranges of muskoxen (Parker and Ross 1976, Wilkinson et al. 1976, Jingfors 1980). Activity budgets of muskoxen (i.e., the proportion of time spent in different activities) during the rut (Smith 1976) and in response to helicopter harassment (Miller and Gunn 1979, 1980) have been described but have not been investigated on a seasonal basis. While muskoxen are considered relatively sedentary (Tener 1965, Gray 1973, Wilkinson et al. 1976, Miller and Gunn 1980), little is known about daily rates of group movement. The objective of this study was to identify ageand sex-specific activity budgets and group movement rates on a seasonal basis for a reintroduced muskox herd in arctic Alaska. Muskoxen from Nunivak Island were released in the Arctic National Wildlife Refuge in northeastern Alaska in 1969. I thank L. G. Sundblad, P. Henrichsen, M. A. Robus, R. D. Boertje, and D. D. Roby for assistance in the field. D. R. Klein, R. G. White, and 2 anonymous reviewers helped improve the manuscript. The data herein are part of a M.S. thesis submitted to the University of Alaska, Fairbanks. Financial assistance was provided by the Alaska Department of Fish and Game through the Alaska Cooperative Wildlife Research Unit. 1 Present address: Northwest Territories Wildlife Service, Department of Renewable Resources, Yellowknife, Northwest Territories X1A 2L9, Canada. 344 J. Wildl. Manage. 46(2):1982 This content downloaded from 207.46.13.33 on Wed, 12 Oct 2016 05:03:45 UTC All use subject to http://about.jstor.org/terms BEHAVIOR OF REINTRODUCED MUSKOx *Jingfors 345