The Pika, also known as the sounding rat and the stone rabbit,belonging to the rabbits. Ochotonidae belongs to the animal.There are many different species: Ochtona Thibetana, Ochotona Hyperborea, Ochotona Daurica, Ochotona Alpina Pallas,Ochtona Macrotis Gunther, etc. . It looks likes a rabbit, but the shape and demeanor are very similar to a mouse. It is small, with short and round ears. Most of them live in high-altitude rocky mountains and dwell in caves they dug. In my country, it is mainly distributed in Inner Mongolia and Gansu. The pika does not hibernate and has the habit of storing food. When winter comes, it will dry the food it gets in the sun for storage. Pikas have always been considered a harmful species. They dig holes in overgrazing pastures which cannot absorb rain well. When monsoon rains come, they will cause serious harm to downstream farmland and cities. However, later studies proved that the degradation of the grassland was not caused by pikas.However,it is because pikas prefer to live in degraded grasslands ，the existence of their caves reduce the flood damage.