Food and feeding habits of commercially important demersal finfishes off Veraval coast

Abstract

Stomach contents of nine species of commercially important demersal finfishes off Veraval coast were examined. Fish samples were collected periodically from the commercial trawlers of Veraval from January 2009 to October 2010. The dietary components of each species was studied and expressed as percentage of numerical composition (CN), percentage of gravimetric composition (CW) and percentage of frequency of occurrence (F). The major food items in the stomachs of each species were determined using an Index of Relative Importance (IRI). The gut contents of the fish varied in number, weight, and their frequency of occurrence with species to species. The study showed that prey items that were smaller in size constituted the major bulk, while the large size prey items were in fewer numbers. Based on cluster analysis (Bray-Curtis similarity) of predator (fish) feeding similarities , six sub-groups and the following three major groups were identified: group I (detritus feeders) comprised Pampus argenteus and Arius thalassinus; group II, (pisces feeders), was the largest group identified and included Saurida tumbil, Saurida undosquamis, Otolithes cuvieri and Johnius glaucus; group III,(shrimp feeders), consisted of Priacanthus hamrur, Nemipterus japonicus and Nemipterus mesoprion. Acetes spp., prawns and juvenile finfishes were the most important food items consumed by majority of the species. The values of the feeding index did not show any significant variation in different months during the two years of observation. However, the feeding intensity was slightly higher during the period of September to December. The results of the present investigation could provide valuable information in formulating strategies for management of fishery resources in the region.