Feeding patterns of the gastropod Lepsiella vinosa on the West Head rocky shore in Victoria

This study used observations of Lepsiella vinosa and surveys of prey species to describe the diet of L.vinosa on rocky shore at West Head, Victoria. The numbers of individual L.vionsa observed feeding were recorded during the surveys of Site 1 and Site 2 from 1975 to 1978 (see ?The population dynamics of the gastropod Lepsiella vinosa on the West Head rocky shore in Victoria? file identifier: 05f4f7f0-f49f-11dc-9f74-00188b4c0af8). In addition, six quadrats (25 x 25 cm) were randomly placed at the 2 sites every 2 months from March 1976 to January 1977. The number and size (measured to the nearest 0.01 cm) of prey species was recorded in each quadrat.

The number of L.vinosa recorded feeding varied seasonally and strongly correlated with the changes in density of prey species. In Area 1, L.vinosa was feeding on Littorina unifasciata for 66% of the observations and Littorina praetermissa, Bembicium nanum, Kellia australis, Nerita atramentosa, Chthamalus atennatus and Zenostrobus pulex for the remaining proportion of observations (n=895). In Area 2, there were fewer observations of feeding L.vinosa (n=53) with the same species recorded as prey items but the majority 34% of L.vinosa was feeding on Nerita atramentosa. Analyses of the data from the quadrats indicated that, in late summer and autumn, L.vinosa reduced its selectivity for prey species, compared to early winter and spring, when they targeted Littorina spp.