Prey selectivity and feeding rates of the scyphozoan Catostylus tagi (Haeckel, 1869)

Abstract

The occurrence of scyphozoan blooms is frequently reported in coastal areas, suggesting a need to assess its impacts on trophic webs. However, many scyphozoan species remain understudied with regard to their feeding ecology. Here, feeding selectivity experiments were conducted to learn about the possible prey preference of Catostylus tagi among mesozooplankton prey and estimate feeding rates. In general, C. tagi demonstrated a relative positive selection on small prey as cyclopoid copepods (Oithona spp. and Oncaea spp.), copepod nauplii as well as non-swimming prey (fish eggs), and ingestion rates increased with prey concentration. Further in situ studies must be conducted during summer blooms, to determine the predatory impact, retrieving data of C. tagi and prey abundance, particularly in important nursery areas such as estuaries.