Contribution of different seston components to ascidian food in Potter Cove

Abstract

The ascidian Corella eumyota Traustedt, 1882 is one of the dominant macrobenthic species within inner Potter Cove, and can reach an abundance of 2.2 individuals m-2. Despite its large size (up to20 cm in length) it shows a depressed shape and it is attached to the bottom by its ventral side. It is commonly covered by mud with the siphons close to the bottom surface. This ascidian was selected for microscopical gut contents analysis to determine its diet throughout the year. Comparison between the erect C. verrucosa and the depressed C. eumyota will help us to understand the structure of the diverse ascidian community that is affected by short-term changes characteristic of Antarctic-coastal ecosystems.