Fig. 3.

Average infiltration rate of water by treatment and location. Error bars represent 1 SEM. Blocking-factor ANOVA was used to test for significant variation in mean infiltration rate of all three treatments across localities. Treatments included measurements on burrow (adjacent to an active pika burrow), On Colony (at least 1 m from active burrows, but within an active pika colony), and Poisoned Site (a location where pikas had been poisoned and old burrows had collapsed). Total sample size for the project was 54 trials with sample sizes varying from nine (three per treatment) to 15 (five per treatment) by locality. Blocking-factor ANOVA (two tailed): F _2,8 = 16.992; P < 0.001. Tukey–Kramer comparisons between sites: Poisoned Site versus On Burrow = P < 0.001; Poisoned Site versus On Colony = P < 0.004; On Colony versus On Burrow = P < 0.001