Fig. 3

Morphological parameter and density Nacella. Nacella maximum body length (a) and body weight (b) of Nacella were measured in tide pools and on emergent rocks (dark- and light-grey bars, respectively). In panels a and b, values are given as means ± standard errors of the mean (SEM). Panel c shows the cross-correlation between the percentage cover of tide pools (x) and density of Nacella (y) in the mid-intertidal zone. In panel c, the height of each bar indicates the correlation estimate at multiple spatial lags between both variables; dotted lines delimit the threshold for statistical significance (CI 95 %) of correlations