Assertion: barren ground caribou | /r/Desires | large annual ranges
Facets:
value: to enable selection of alternative habitats
type: PURPOSE
Source sentences:
text: Barren-ground Caribou require large annual ranges (several hundred thousand square kilometres in size) to enable selection of alternative habitats in response to annual variations in the environment, such as snow cover, plant growth, and/or predation or parasite risk.