Feeding ecology and diet

Like all lagomorphs, pikas are generalized herbivores. Their most characteristic feeding behavior is the gathering of vegetation during summer that is stored in a centralized cache, or haypile, to serve as food during winter. Again like all lagomorphs, pikas excrete two types of feces and commonly reingest the soft viscous feces.

Pikas are most active during the mid- to late summer when they begin to gather vegetation with which to construct their haypile. At this time, a flurry of activity ensues with animals sometimes making one round-trip per minute to the adjoining meadow to pluck a long stem of a succulent herb. Commonly, a pika will sit on a rock briefly, utter a short call to proclaim its territory, rush to the meadow for a mouthful of vegetation, rush back, deposit the load, quickly give another call, and rush off again. The haypiles constructed by members of a pair are normally located on their territory closer to the territory of their pair mate rather than centered on their territory. Pikas forage for vegetation off of the talus, gener-

A Himalayan pika (Ochotona sp.) climbs on top of a rock, Ladakh, India. (Photo by Gertrud & Helmut Denzau/Naturepl.com. Reproduced by permission.)

ally close to the talus-meadow interface. Their behavior when feeding contrasts sharply with that of when they are gathering hay. Feeding pikas pluck individual small stems, generally of grass, which they eat while maintaining an alert posture; they appear to be extremely wary of predators while feeding. Pikas gather vegetation for their haypiles at far greater distances from the talus and, in contrast to their alert posture while feeding, appear foolhardy and unaware of predators while gathering hay. They try to get the largest mouthful of vegetation that they can, often diving at the base of a forb to clip it off.

0 0

Post a comment