Periodical Variations of Weight and Fat Reserves in Onychostruthus taczanowskii
Author of the article:WANG Ai-zhen1,2 , LEI Fu-min2*
Author's Workplace：(1. Department of Biological Sciences, Qinghai University, Xining 810016, China; 2. Institute of Zoology, the Chinese Academy of Sciences, Beijing 100101, China)
Key Words：Onychostruthus taczanowskii; weight; fat; periodical variation
Abstract：The periodical variation of the weights and fat reserves in white-rumped snowfinch (Onychostruthus taczanowskii) among early spring, nursing nestlings, and molting was investigated by weighting and semi-quantitatively scoring fat reserves after the birds were captured with mist net in Xinghai and Henan county, Qinghai province. The cloaca protuberance was measured with vernier caliper in early spring to investigate its development with day-length changes. Further, the effect of fat level on individual variation of cloaca development initial time was analyzed. The results show that the weight and fat of white-rumped snowfinch increase from February to March, drop when nursing nestlings, and gain increase while molting. The cloaca initiated development in February and March. The data of fat score and cloca protuberance indicated that initial time variation of cloaca development between individuals in white-rumped snowfinch is correlated with their fat reserves.