关键词: 甘肃鼠兔, 干草堆, 栖息地植被类型, 鸣声, 平行发育

Abstract: Composition of haypile caches as winter food by Gansu pikas ( Ochotona cansus) and it's relationships to habitat vegetation type were studied based on the 27 hay-piles collected in late fall of 1999 from meadow , shrub , and old fields at the Haibei Research Station of Alpine Meadow Ecosystem , the Chinese Academy of Sciences. The results showed that each hay-pile had a dried weight of 23.8 - 984.2 g with average of 184.2 g , and no significant difference was detected between samples collected from meadow , shrub , and old fields. There were 26 species of dicotyledons and some unidentified monocotyledons in Gramineae in the hay-pile materials. The proportion of dicotyledons in dried weight was 84.61 % , much higher than that of monocotyledons (8.06 %). Compared to their proportions in the environment (39.57 % for dicotyledons and 51.76 % for monocotyledons) , this meant that Gansu pikas preferred dicotyledons to monocotyledons when they cached their winter food. Preferences of plant materials were relatively stable , even though their availability in habitats affected their proportions in hay-piles. The most preferring plants were Saussurea superba , Oxytropis spp. , Gentiana straminea , some grasses in Gramineae , and Gentiana farreri. Overwinter survival of Gansu pikas reduced from 51.84 % for control plot ( 1 hm2) to 21133 %for treatment plot ( 1 hm²) by removing hay-piles , implying that cached food was critical for the animal to live over the winter. Field observations indicated that vocal behavior of Gansu pikas developed poor than that of sympatric plateau pika ( Ochotona curzoniae) without the habit of caching winter food. This disagreed with Kawamichi's (1976 , 1985) opinion that the development of calling parallels the occurrence of harvesting behavior.

Key words: Gansu pika ( Ochotona cansus), Hay2pile, Habitat vegetation type, Vocal behavior, Parallel development