Trapping of three drilling whelks by two species of mussel

Abstract

The mussels Choromytilus meridionalis (Krauss) and Mytilus galloprovincialis (Lamarck) coexist with the predatory drilling whelks Nucella cingulata (Linnaeus), N. dubia (Krauss) and N. squamosa (Lamarck) on the west coast of southern Africa. Samples revealed that these whelks are trapped by byssus threads in intertidal mussel beds. Nucella of each species were enclosed with high and low densities of each mussel. Both mussels attached byssal threads to large numbers of all the Nucella species, and trapped some of those attacked. When M. galloprovincialis were enclosed with the non-drilling whelks Burnapena catarrhacta (Gmolin) and B. limbosa (Lamarck), the mussels attached few threads to the ..