The Effect of Muskox Herbivory on Growth and Reproduction in an Arctic Legume
Mulder CP and Harmsen R. 1995. The Effect of Muskox Herbivory on Growth and Reproduction in an Arctic Legume. Arctic and Alpine Research. 27(1):44-53
The effect of muskox herbivory on growth and reproduction in Oxytropis viscida was examined on Banks Island, N.W.T, during three growth seasons. Two levels of grazing were recognized. "Chomping," which occurs primarily early in the season, affects shoot tips and may include removal of all aboveground biomass. Chomping does not affect survival, but reduces plant diameter and probability of flowering for at least 2 yr following grazing. It also decreases the number of shoot tips during the year of grazing, and decreases the number of inflorescences for at least 1 yr following grazing. Chomping results in a change in plant morphology, including more tightly clustered growth tips and greener, more viscid leaves. Chomped plants are less likely to be grazed again in the year following herbivory. "Nibbling" refers to the selective removal of inflorescences and seed pods. Nibbling does not affect plant survival, shoot tip number, or number of inflorescences, but does decrease diameter for at least 1 yr following grazing. Results suggest that O. viscida may not be continually defended and that resistance is induced by chomping but not nibbling. The strategy of this arctic herbaceous dicotyledon appears to be intermediate between that of arctic graminoids which exhibit rapid regrowth and that of slower growing, highly defended arctic shrubs.
- Type
- Journal Article
- Authors
- Mulder, Christa; Harmsen, Rudolf
- Units
- ARCN , BELA , CAKR , GAAR , KOVA , NOAT
- Keywords
- allocation, Arctic, banks island, Caribou, grazed salt-marsh, leaf, Lesser Snow Geese, nitrogen-fixation, Responses, tundra plants, Vegetation