Perhaps they seem like a wildlife Mutt and Jeff—the elk, a majestic deer weighing 700 pounds, a mountain king known for his haunting autumn bugling and magnificent rack of antlers; the pika, a six ounce furball, busily defending his rock-pile home with squeaks and warning barks. Certainly no two mammals could be less alike.
Yet in the scheme of energy transfer, the elk and pika are very alike. Both are herbivores, first level consumers with a vital role in converting plant tissue to animal tissue. Under this broad definition, the two species perform the same job, yet the contrasts between them illustrate the diversity of life. Though both are plant eaters and often found in the same habitat—alpine meadowlands—competition between elk and pika is kept to a minimum because they occupy different niches. Pika eat among the boulder piles that elk find difficult to navigate. And although there is overlap in food choice, elk are primarily grass-eating grazers and pikas are nibblers of alpine shrubs and forbs.
Elk and pika also use different strategies to complete digestion of plant material. Like cattle, elk are ruminants with chambered stomachs. Food is moved through successive chambers, each pouch furthering the digestion process. Partially digested food is regurgitated into the mouth where it is remasticated—elk chew cud.
As members of the rabbit family, pika have an equally charming mode of digestion—coprophagy. Food passes once through the animal's digestive system and is excreted as soft, green caecal pellets (not to be confused with the hard, brown fecal pellets). These soft pellets are then re-ingested by the pika to pass through the intestines again for final processing. Sort of another way of chewing cud. . .
Next: Do Beavers Eat Fish?
(The information contained in these issues of Colorado's Wildlife Company was accurate at the time of original publication. Situations and circumstances described, staff positions, contact information, and dates of some events may have changed in the interim. Present knowledge and understanding of biological and behavioral facts and information may also be different than presented here.)