The Effects on Target, By-Catch and Discard Catch of Using Multifilament and Monofilament With Selvedge (Guarding Net) on the Trammel Nets in the Black Sea Coastal Fisheries

Abstract

This study was carried out in 13 fishing operations in the inner harbor area of Sinop, from September through November of 2004. Trammel nets were used, which has 32 mm mesh size and target fish species of the fishing gear is red mullet (Mullus barbatus) in the study. Three net groups were used in the experiments, without selvedge (A0) for the control net, multifilament with selvedge (A1) and monofilament with selvedge (A2) respectively. 65.3% Osteichthyes fish (696 individuals), 16.8% Mollusca (179 individuals), 16.4% was Arthropoda (175 individuals) and 1.5% was Chondrichthyes fish (16 individuals) of catch obtained from the operations were form. A total 124 individuals as the target species (red mullet), 398 individuals as bycatch species, and 544 individuals as discarded species were captured sea trials. Catch ratio of A0, A1 and A2 nets were determined 51.88%, 21.58% and 26.55% respectively. 48.38% of the target species, 30.40% of the bycatches and 57.53% of the discarded catch were caught by the A0 net. 25.81% of the target species, 45.23% of the bycatches, and 18.57% of the discard catch were caught with A1 net. 25.81% of the target species, 24.37% of the bycatch and 24.37% of the discarded catch were caught by the A2 net. The results showed that the use of selvedge (guarding net) on trammel nets in the Black Sea coastal fisheries caused a slight decrease in target fish catch, but significantly decreased the amount of discarded catch.

Keywords

• Coastal fisheries
• Trammel net
• Bycatch
• Discard
• Black Sea

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