Growth rate of the gastropod Lepsiella vinosa on the West Head rocky shore in Victoria

This study used a mark-recapture method to examine the patterns of shell growth of Lepsiella vinosa on the rocky shore at West Head, Victoria. Individuals were collected from the West Head shore on 24th March 1974 and 29th May 1975. They were transported back to the laboratory and marked with individually labeled tags. The next day they were released in the field in the areas from where they were collected. Study sites 1 and 2 were searched on 36 occasions between 25th April 1974 and 28th June 1978. The number of marked individuals, the number of unmarked individuals, and the shell length of marked individuals in the study sites were recorded. When marked individuals were recpatured on successive 1-month or 2-monthly sampling occasions the monthly or mean monthly growth-increments were calculated.

There was a total of 254 marked individuals recapture and a total of 626 growth increments recorded. The growth rate of L.vinosa depended on the size of the individual and ranged between 0.025 and 0.4 cm per month. Maximum growth of L.vinosa in all size classes occurred between September and October. Variation in growth rate between seasons was most evident in size classes from 1.00 to 1.09 cm and less pronounced in larger size classes from 1.10 to 1.59cm.