| Abstract: | Field observations were carried out on the Gansu pikas, Ochotona cansus Lyon, in its natural habitat from July 1987 to November 1988 at Haibei Alpine Meadow Ecosystem Research Station,Qinghai Province,PRC. Communicative behavior, reproductive behavior, spatial and social organization of the Gansu pika were described, and their adaptive significance discussed.The major communicative methods are acoustical and olfactory.At least four types of call (long call,short call, trill and whine)were distinguished. The peculiar habits of vocalization of species in the genus Ochotona appear to be the result of adaptation to boreal and/or high altitude severe climates.Two types of scent marking patterns were observed, and faeces play an important role in olfactory communication. Mother-infant relationships differ from most small rodents, but resemble those of medium-sized lagomorphs. The suckling time is "scheduled", and the frequency seems positively related to litter-size. This mother-infant relationship is thought to be advantageous to reduce the risk of predation and to minimize the energy investment of the mother for raising young (thus ensuring successful reproduction during the next breeding season). The social organization of the Gansu pika can be classified as "solitary-ranging pair", and the male-female bond is stable through most of the year. This Species exhibits a facultative monogomy mating system. The annual cycle of social pattern can bedivided into four phases based on social activities:Spring, family, rearrangement and winter (or stable) phase. In the family phase, home range sizes of adults reach their maximum, thus leaving sufficient activity space for the young and reducing potential parent-offspring competition.The stable pair bond through winter seems to be beneficial to overwinter survivorship and successful reproduction in the coming year. |
