Fig. 5. The frequency of net population growth rates during winter and summer in 84 populations of gray-sided voles from Hokkaido, Japan. Net population growth rates are given, only for this figure, as follows: R_wt = ln(z_s,t + 1) - ln(z_f,t-1 + 1) and R_st = ln(z_f,t + 1) - ln(z_s,t + 1), where z_s,t and z_f,t are abundance index for spring and autumn, respectively.