Diet composition and feeding habits of Trachurus japonicus And Scomber Spp. larvae in the shelf break region of the East China Sea

• Autores: Chiyuki Sassa, Youichi Tsukamoto, Yoshinobu Konishi
• Localización: Bulletin of Marine Science, ISSN 0007-4977, Vol. 82, Nº. 1, 2008, págs. 137-153
• Idioma: inglés
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• Resumen

  • The feeding habits of larvae of co-occurring jack mackerel Trachurus japonicus (Temminck and Schlegel, 1844) and mackerels Scomber spp. in the shelf break region of the East China Sea were examined and compared. These larvae showed a high feeding incidence for daytime samples (82.9%-100% and 78.9%-96.2%, respectively). Prey size increased with larval development, while niche breadth was independent of larval size, and did not change during development for either taxon. The number of prey consumed was positively correlated with body length for T. japonicus, but not for Scomber spp. Although copepod nauplii and Paracalanus parvus were highly consumed by both T. japonicus and Scomber spp. larvae, the differences in prey composition were (1) the diversity of prey items in T. japonicus was much higher than that of Scomber spp. throughout the larval stage; (2) the gut contents of T. japonicus and Scomber spp. larvae > 6 mm in body length were mainly characterized by poecilostomatoid copepodites and appendicularians, reoecilostomatoid and spectively. The dietary overlap based on Schoener's index revealed low dietary affinities (35.6%-47.1%) between T. japonicus and Scomber spp. throughout the larval stage, illustrating their diet segregation.