Figure 5

Temporal patterns of environmental gradients during the reproductive cycle Diadema setosum.

Monthly gonad index (GI_W) calculated as wet gonad weights/total wet body weight × 100 of Diadema setosum from the GOA and monthly gradients of selected environmental variables. Boxes represent monthly GI_W; centre black lines show the medians; box limits indicate the 25^th and 75^th percentiles; the 95% confidence interval of each median is represented by the notches and is defined as +/−1.58 × IQR/sqrt(n) (with n representing the monthly number of samples); whiskers extend to minimum and maximum values with open circles representing outliers; width of the boxes is proportional to the square root of the sample size. Indexes calculated based on 20 specimens per month. No data are available for January 2011. The colour of the boxplots corresponds to the dominant reproductive stage of that month (see Fig. 4 for details). Grey zone illustrates photoperiod. Red line illustrates daily measured sea surface temperatures (°C) and green line illustrates daily measured chlorophyll-a concentrations (μg/l) fitted as a smooth curve (solid lines) and standard errors (shaded margins). The smooth was calculated by local polynominal regressions.