Size-related changes in predatory behaviour of naticid gastropods from the Middle Miocene Korytnica Clays, Poland

The analysis of shell-drilling predation by naticid gastropods on molluscs from the Korytnica Clays (Middle Miocene, Holy Cross Mountains, Central Poland) has focused on the bivalve Corbula gibba and gastropods Natica tigrina and Hinia restitutiana. The results indicate that predatory behaviour of naticids varies depending on the size of the predator. When drilling corbulids, large naticids displayed higher site-selectivity than smaller naticids. Also, large naticids drilled energetically attractive prey (Hinia restitutiana and Natica tigrina) more frequently than small naticids. Preferential drilling displayed by large naticids from the Korytnica Clays increases the net energy gain for the predator and in result allows it to drill more effectively.