Analysis of the feeding ecology of the sea anemone Bunodosoma zamponii: populations under differential anthropogenic pressures

Abstract

The feeding ecology of two populations of the sea anemone Bunodosoma zamponii Schama and Solé-Cava, 2012 living under different anthropogenic pressures in the coast of Mar del Plata (Buenos Aires, Argentina) was studied. One population was located in Las Delicias (LD, an impacted site adjacent to a wastewater treatment plant) and another in Punta Cantera (PC, the reference site). Both populations of sea anemones were monitored for two years and their trophic ecology was analyzed. The mytilid Brachidontes rodriguezii (d'Orbigny, 1842) was the main item found throughout all seasons. Prey diversity was highest in PC during autumn and lowest during winter for both sites. Prey abundance was lower in LD during autumn and summer. Additionally, prey items were larger in PC during autumn, winter and summer. Item capture probability in autumn was significantly lower in LD. Altogether, the results indicate that the diet of B. zamponii differed significantly between sites and such differences varied throughout the year. Most of the differences occurred during autumn and winter, which corresponds with a greater concentration of organochlorine pesticides, chlorpyrifos and polychlorinated biphenyls in anemones from LD registered in previous studies. Overall, this study provides significant knowledge on the feeding ecology of Bunodosoma zamponii that complements the existing information and will provide meaningful insight into the current status of this anemone’s populations.