Comparative Evaluation of Barbed and Barbless Hooks in Artisanal Longline Fishing: Hooking Efficiency, Catch Dynamics, and Fuel Economics off Panambur Coast, South-Eastern Arabian Sea
A. N. Nikhil
*
Department of Fisheries Engineering and Technology, College of Fisheries, Mangaluru, Karnataka, India.
Mayur Tandel
Department of Fisheries Engineering and Technology, College of Fisheries, Mangaluru, Karnataka, India.
Ishani S. Gowda
Department of Fisheries Extension, Economics and Statistics, Fisheries College and Research Institute, India.
Jaya Naik
Department of Fisheries Engineering and Technology, College of Fisheries, Mangaluru, Karnataka, India.
Prapthi Mendon
Department of Fisheries Engineering and Technology, College of Fisheries, Mangaluru, Karnataka, India.
Tamil Prakash
Department of Fisheries Engineering and Technology, College of Fisheries, Mangaluru, Karnataka, India.
Appanna Jyothika Rani
Department of Fisheries Engineering and Technology, College of Fisheries, Mangaluru, Karnataka, India.
*Author to whom correspondence should be addressed.
Abstract
Background: Hook design is an important factor influencing catch retention, hooking efficiency and fish injury in artisanal longline fisheries. Although barbless hooks may reduce hooking-related injuries and facilitate easier fish release, their effects on catch productivity and operational efficiency remain insufficiently documented in tropical small-scale fisheries.
Aims: To evaluate and compare the hooking efficiency, species selectivity, total catch biomass, and operational fuel economics of barbed versus barbless terminal hooks rigged on motorised artisanal longlines.
Study Design: Comparative experimental field fishing trials using an alternating hook deployment regime across consecutive commercial voyages.
Place and Duration of Study: The study was conducted in neritic coastal waters off Panambur, Mangaluru (south-eastern Arabian Sea), Karnataka, India, between Station 1 (12°56'50.9" N, 74°20'27.9" E) and Station 2 (12°56'37.4" N, 74°41'03.7" E) along a continuous 30 m depth contour, with fortnightly sampling over 18 voyages between December 2024 and August 2025.
Methodology: Experimental longline gear comprising a 200 m polyamide monofilament mainline (0.60 mm) and 100 branchlines (0.30 mm, spaced at 2.0 m) was deployed from a 10-m fibreglass-reinforced plastic (FRP) canoe powered by twin 9.9 HP dual-fuel outboard motors. Exactly 50 barbed and 50 barbless forged stainless steel hooks (40 mm) were arranged alternately along the mainline and baited with live carangids and mackerels. Total landed biomass, species composition, hooking ability (HA), and trip fuel expenditures were recorded and evaluated using two-sample independent Student's t-tests.
Results: Barbed hooks demonstrated significantly higher mean hooking efficiency (0.52 ± 0.10) than barbless hooks (0.23 ± 0.07; t = 10.037, P < .001). Cumulative landed biomass across 18 voyages totalled 8019.00 kg, with barbed hooks accounting for 89.16% (7150.00 kg; voyage mean: 397.22 ± 61.43 kg) and barbless hooks contributing 10.84% (869.00 kg; voyage mean: 48.28 ± 2.37 kg; t = 24.080, P < .001), representing an 87.8% catch reduction. The landings were dominated by Katsuwonus pelamis (62.68%) and Scomberomorus commerson (19.35%). While barbless hooks caused zero deep-visceral trauma, wave-induced heave and manual line slack induced severe escapement. Average voyage fuel consumption was 70.09 ± 0.81 L, translating to a specific fuel expenditure of 0.176 L/kg for barbed gear versus 1.452 L/kg for barbless gear (an 8.25-fold escalation).
Conclusion: A complete conversion to barbless hooks severely compromises the economic viability of small-scale longline fishers operating under coastal auction/share systems. Intermediate terminal modifications such as micro-barbed or semicircular offset hooks are recommended for balanced conservation and catch retention.
Keywords: Artisanal longline fisheries, barbed hook and barbless hook, hooking ability, Panambur coast, Arabian Sea