ON THE SEX-RATIO OF THE PAINTED GHOST CRAB OCYPODE-GAUDICHAUDII EDWARDS,H.MILNE AND LUCAS, 1843 (BRACHYURA, OCYPODIDAE)

The sex ratio of the painted ghost crab Ocypode gaudichaudii is 1:1. W hen sampled in different areas of the intertidal zone, the number of m ales and females varied according to differences in their spatial patt erns of behaviour. Male crabs that remained in the burrow area, i.e., the upper third of the beach, at low tide outnumbered females 2:1. Lar ge sexually mature males were more abundant in the upper third of the beach in the burrow area than near the low-tide mark. Equal numbers of males and females foraged away from the burrow area at the waters edg e. Twice as many females were captured away from the burrow area than in it. Previous reports of skewed sex ratios may have resulted from sa mpling bias introduced by the different behaviours of each sex.