In 1981, Kitchell et al. envisaged a net energy maximization
model that can rank different prey according to their preferences.
Several workers tested the model both in experimental
studies and in fossil records. In the present endeavor we have
tried to analyze the nature, from a cost-benefit perspective, of
naticid predation on two Recent prey bivalve species Mactra
luzonica Reeve, 1854, and Donax scortum Linnaeus, 1758,
collected from eastern coast of India. The results have broadly
supported the theoretical cost-benefit curve of Kitchell et al.
(1981). While Mactra luzonica was thoroughly preyed upon
regardless of body size, predation on Donax scortum significantly
decreased after prey body size exceeds 3 cm. This is
explained on the basis of a change in mode of living of the prey
during late ontogeny. Other factors like prey availability, prey
ornamentation, consumption rate, and presence of secondary
predators that may constrain the model, have been discussed.