Foraging dynamics of muskoxen in Peary Land, northern Greenland
Muskoxen Ovibos moschatus in northern Greenland (79‐83°N) are at the northern limit of their distribution and exist under seasonal extremes dominated by nearly 10 months of winter, much of which is without sunlight. The period of summer vegetative growth is less than two months. In the Kap København...
| Published in: | Ecography |
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| Main Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Wiley
1990
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1111/j.1600-0587.1990.tb00619.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1600-0587.1990.tb00619.x https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1600-0587.1990.tb00619.x |
| Summary: | Muskoxen Ovibos moschatus in northern Greenland (79‐83°N) are at the northern limit of their distribution and exist under seasonal extremes dominated by nearly 10 months of winter, much of which is without sunlight. The period of summer vegetative growth is less than two months. In the Kap København area (82°30′N), diversity of plant species is low (76 species of vascular plants) and forage biomass in major vegetation types in summer varies from over 40 g m ‐2 in sedge‐dominated fens to ≤5 g m ‐2 in polar barrens. Nonetheless, 90‐95% of the ice‐free area consists of barren ground or sparcely vegetated polar desert. During summer, muskoxen apparently foraged opportunistically to maximize intake, with sedges the major food item in fens while willows were the major dietary component when on willow‐dominated slopes. Quality of summer forage was high during its early phenological stages, with 21‐28% crude protein and 60‐75% in vitro digestibility. Microhistological analysis of winter feces indicated dominance by graminoids. Muskoxen spent > 50% of their daily activity feeding, which fits a cline of increasing feeding time with increasing latitude in summer. Increased feeding times at high latitudes appears to be a function of both reduced forage biomass and need to maximize forage intake during the brief summer period when forage quality is high. Movement rates in summer while foraging were inversely related to available forage biomass. Seasonal activity of muskoxen peaks during the rutting period (July‐September) and then declines gradually through early winter to a low in late winter (March‐April). |
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