关键词: 啮齿动物, 黄胸鼠, 季节消长

Abstract:

Objective　To investigate and determine the composition, distribution and biological characteristics of rodent populations in Baoshan. Methods　Multi?year survey and monitoring were conducted. Results　A total of 46 species, 21 genus and 6 families of rodents were found in Baoshan district. Rattus tanezumi a key storage reservoir of Yersinia pestis, was the dominant species, accounting for 58.73% of the total captured rodents. Density peaks appeared in the indoor environment in April, August and October, whilst they presented in May and September in the fields. This kind of rats could breed throughout the year with an average annual pregnancy rate of 5.48%, maximizing in April and May (8.62% and 9.01%), followed by the period from August to October (6.31%-7.38%), and reaching the bottom in January (2.81%). The bimodal pattern of pregnancy rates was featured by a noticeable initial peak in spring and early summer that was significantly higher than the autumn peak (t＝7.345, P＜0.01). The sex ratio of R. tanezumi revealed a higher proportion of females than of males. Conclusion　Large?scale rodent control has not only significantly reduced the number of R. tanezumi, but also altered the seasonal pattern in the population dynamics, which may play an inhibitory role in the long?term dynamics of Y. pestis.

Key words: Rodents, Rattus tanezumi, Seasonal fluctuation