POPULATION CHARACTERISTICS AND FOOD RESOURCE UTILIZATION OF CONUS IN THE SEA OF CORTEZ AND WEST MEXICO

The diets and population characteristics of three abundant speciesof Conns, nux, diadema and princeps, from the Sea of Cortezare described. All were found to feed predominantly upon polychaeteworms. In addition, food notes are presented for six less abundantspecies from the same area. Comparison of the diversity of thediets of the three dominant species in the Sea of Cortez withcognate species in the Indo-West Pacific, where significantlymore congeneric species occur in any single habitat, indicatedno significant increases in diversity of prey. This lack ofecological release with respect to food in the presence of fewercompeting congeners was attributed to the presence of significantlyfewer prey species when compared to the Indo-West Pacific. (Received 23 March 1978;