Sand disposal of the painted ghost crab Ocypode gaudichaudii (Decapoda: Ocypodidae): A possible role in courtship

In 1991/1992, we studied the sand disposal behavior of the painted ghost crabs Ocypode gaudichaudii on the Pacific coast of Panamá. O. gaudichaudii either kick, dump or tamp sand they excavate from their burrows. Here we relate these three kinds of sand disposal to burrow structure and distribution, as well as to crab size and sex. Our objective was to determine whether tamping may be a male courtship signal. Burrows whose owners tamped sand were on average longer, deeper, and higher on the beach than were burrows whose owners kicked or dumped sand. Five burrow shapes were distinguished, with half-spiral and spiral shapes being most common among tamped burrows. All crabs excavated from tamped burrows were males. Tamped burrows peaked in abundance around full and new moons. These observations, together with what is known about mating and breeding behavior of other ghost crabs, suggest that tamping may be involved in O. gaudichaudii courtship.