Manjunathan, M.; Ravikumar, T.; Chandran, S.; Neethiselvan, N.; Jawahar, P.; Arisekar, U., and Karthy, A., 2023. Catch efficiency and economic analysis for traditional fishing gear (troll lines) operated along the Coromandel and Gulf of Mannar coasts (southeast India). Journal of Coastal Research, 39(6), 1137–1145. Charlotte (North Carolina), ISSN 0749-0208.

This study evaluated the effects of three different J hook types, single hook no. 6, double hook no. 6, and triple hook no. 8, on catch rate, catch composition, and economics of two traditional troll-line methods used along the southeast coast of India. Traditionally, the hand- and leg-held troll line has been used in the Gulf of Mannar (GoM), and the outrigger boom-held method has been used on the Coromandel (CoM) coast. The studies were conducted at fortnightly intervals between June 2020 and January 2021. The overall catch rate (no. h²¹) was found to be highest with the double hook (0.6 fish h²¹) and lowest with the triple hook (0.04 fish h²¹) on the CoM coast, while the single hook (0.34 fish h²¹) and triple hook (0.02 fish h²¹) showed the highest and lowest catch efficiency along the GoM coast, respectively. The catch composition was constituted by Scomberomorus commerson (36%), Auxis thazard (18%), Euthynnus affinis (16%), Caranx ignobilis (13%), Thunnus albacares (9%), Scomberomorus guttatus (7%), Coryphaena hippurus (0.8%), and Istiophorus platypterus (0.2%) in the GoM, while it was Thunnus albacares (45%), Euthynnus affinis (18%), Auxis thazard (14%), Istiophorus platypterus (7%), Coryphaena hippurus (6%), Acanthocybium solandri (5%), Scomberomorus commerson (3%), and Caranx ignobilis (2%) on the CoM coast. The chi-square test showed a significant correlation between hook type and fish composition (χ² = 9650.6, df = 16, p < 0.05). The current study demonstrated a net profit improvement of 3313 rupees/trip at GoM and 2093 rupees/trip at CoM. The benefit-cost ratio (B:C) for GoM and CoM was calculated to be 1.84 and 1.76, respectively.