(a) Spatial distribution of sampling stations during the study period. PNBA = Parc National du Banc d'Arguin. The three latitudinal strata (North, 20°36N−19°15N; Central, 19°15N−17°45N; and South, 17°45N−16°03N) are represented by dashed lines. (b) Timing of the surveys (month) for each of the hot and cold seasons. The mean and coefficient of variation of the timing of the surveys by season are given in blue. (c) Number of surveys per year.