RAPA WHELK (Rapana venosa Valenciennes, 1846) FISHERY ALONG THE TURKISH COAST OF THE BLACK SEA

Abstract

In this study, the current situation of an invasive gastropod rapa whelk fishery with dredges and hookah systems were comparatively evaluated. On the other hand, a socio-economic analysis was conducted to evaluate the hookah (diving) system via face to face interviews. There were 207 vessels legally operating in the research area for whelk fisheries 108 of which were using the hookah system. Mean length and engine power of the hookah vessels were 8.8 m and 65 HP, respectively. It was also found that the average CPUE   was 1050 kg/day and income rate was 79%, suggesting that whelk fishing had a high economic gain. Each of the hookah vessels provided an employment to average 3 individuals. According to the results, mean lengths of whelks harvested with dredges and hookah vessels were 5.61 cm and 5.83 cm, respectively. Length-weight relationship of the total production was determined as W=0.0223L^2.965 (R²=0.85). It was concluded that the hookah system is more environmentally friendly method for the ecosystem than dredges. 

Keywords

• Rapana venosa,Black Sea,Dredging,Hookah systems

Kaynakça

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