An evolutionary habitat selection by the plateau pika (Ochotona
curzoniae) in relation to an irrelevant phylogeny agent of the livestock
management on the Qinghai-Tibetan plateau
Abstract
Misunderstanding of the function of the plateau pika (Ochotona
curzoniae) results in diminishing the diversity of both fauna and flora
species and collapse of the the food on the Qinghai-Tibetan plateau. We
used data obtained during an 11-year period to observe evolutionary
habitat selection by the plateau pika in relation to an irrelevant
phylogeny agent of livestock management. We hypothesized that local
nomads are the irrelevant phylogeny agent in the Kobresia ecosystem of
the Qinghai-Tibetan plateau. In order to verify the above hypothesis,
distance to nearest yak-bedding areas and dung management are the
variables that most strongly explains variation in pika occupancy
probability and probability of occupancy detection based on free-ranging
livestock. Both occupancy and detection probability of pikas decrease
sharply with increasing distance to nearest yak-bedding area, strongly
suggesting that pika population densities are highest closest to
yak-bedding areas. There is a strong correlation between dung cover and
occupancy of the plateau pika—namely, the more dung drying on the
ground; the more plateau pikas occupy the area. After the dung has
damaged the grass, plateau pikas are apparently detected there. Thus,
rangeland dominated by sedges of the genus Kobresia on the
Qinghai-Tibetan Plateau is modified by livestock grazing and management,
especially dung management. This is the first reported evidence that
local nomads may cause expansion of the habitat of the plateau pika and
its occupancy.