Resumen
Methodology: The data are 29 sediment samples and these were collected (September 2006) each 200m in a parallel transect on the low spring tide level in a sandy beach of the Caribbean coast of Costa Rica. The data are counts of individuals of marine invertebrates. The samples were taken with a cylindrical core of 18.86 cm2 to a depth of 15 cm into the sediment. The data are part of the project 808-B4-117 of CIMAR, Universidad de Costa Rica.