Feeding Habits of Larvae and Juveniles for Hilsa Shad Tenualosa ilisha (Hamilton, 1822) in Southern Iraq

A total of 646 stomachs were examined to assess the food components of Tenualosa ilisha at different developmental stages—209 from larvae and 437 from juveniles. Ichthyoplankton samples were collected from the eastern part of Al-Hammar and the Shatt al-Arab River using conical nets equipped with a flow meter. The larvae of T. ilisha fed primarily on zooplankton. Throughout the larval stage of their life cycle, the larvae exhibited continuous feeding activity and did not show any signs of cessation. In contrast, phytoplankton constituted the dominant food source for juvenile fish. The relative importance index (IRI) of T. ilisha larvae revealed five main dietary groups: Copepoda (including adult and larval stages), Cladocera (Daphnia spp.), Rotifera, and detritus. The respective proportions of these groups in the IRI were 28, 15, 26, 20, and 11% for copepods, cladocerans, rotifers, and detritus, respectively. Among the juveniles, diatoms represented the largest portion of the IRI at 42%, followed by algae (27%) and detritus (11%), while Cladocera contributed almost as much as Copepoda (10%).