Time percentage (mean ± SE) spent by intact and ablated crayfish in each of the two sides of the walking arena in 50–78% RH chambers (n = 16 for the intact crayfish and n = 12 for the ablated ones), 60–75% RH chambers (n = 16, only intact crayfish), and in the control (n = 18 for intact crayfish and n = 12 for ablated ones). For controls, no significant differences were recorded between behaviour of ablated and intact crayfish so they were pooled together. Data from the whole experimental time, 90 min, and from the first min of the test are analysed independently. ****P < 0.0001, ***0.0001 < P < 0.001; ns, not significant (t-tests for dependent samples). Data with different letters are significantly different at P < 0.05 (one-way ANOVA, unequal N HSD Tukey test).