Seasonal variation in the food and feeding habits of Setipinna taty (Valenciennes, 1848) inhabiting the Hooghly-Matlah estuary of West Bengal, India

Abstract

The food and feeding habits of Setipinna taty collected from the Hooghly-Matlah estuary, West Bengal, India, for a period of 12 months (February 2022 to January 2023) were studied. Zooplankton, crustaceans, insects, annelids, and molluscs have dominated the food items in the gut. Throughout the year, there were a very high percentage of empty stomachs. The Empty Stomach Ratio (ESR) value was highest in males during the pre-monsoon, and for females, it was higher in the post-monsoon. The mean Relative Length of Gut (RLG) value varied from 0.3147 to 0.389 in males and 0.323 to 0.425 in females. RLG values were found to be highest during the monsoon and lowest during the post-monsoon for both sexes. The species is a carnivorous fish and feeds mainly on zooplankton and crustaceans. The feeding intensity is higher in the adult stage, with crustaceans and insects dominating the gut contents, while zooplankton and annelids are preferred by the juveniles. Among the zooplankton, the main food items are copepods, rotifers, lichens, and crustaceans, mainly megalopa larvae, alima larvae, Labidocera sp., and unidentified shrimps. Among non-penaeid prawns, Acetes spp. was the most dominant food item. Bray-Curtis similarity shows 66 – 70 % similarity between the pre-monsoon season and both the monsoon and post-monsoon seasons. According to the Bray-Curtis similarity index, the seasonal diet variations of anchovy were alike each other by 66 – 70 %.