Turkish Journal of Fisheries and Aquatic Sciences
2015, Vol 15, Num, 3 (Pages: 561-567)
Effect of Hanging Ratio on Selectivity of Gillnets for Bogue (Boops boops, L. 1758)
Can Ali Kumova 1 ,Uğur Altınağaç 1 ,Alkan Öztekin 1 ,Adnan Ayaz 1 ,Alparslan Aslan
1 Çanakkale Onsekiz Mart University, Faculty of Marine Sciences and Technology, 17100, Çanakkale, Turkey
DOI :
10.4194/1303-2712-v15_2_44
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This study was conducted between November 2011 – January 2013 on Bogue gill nets in mesh size of 36, 40, 44 and 50
mm targeting bogue (Boops boops, L. 1758), which is used in commercial fishing commonly at Canakkale shores. The bouge
nets were rigged in three varying hanging ratios (E=0.40, E=0.50, E=0.60) with the purpose of determining the effect of
hanging ratio to selectivity. SELECT (Share Each Lengthclass Catch Total) method was used to fit selectivity curves.
Lognormal model gave the best fit for selectivity curve of bogue selection according to the findings obtained from five
different curve models (normal location, normal scale, gamma, lognormal, bimodal). According to the lognormal method
modal lengths of bogue nets in mesh size of 36, 40, 44 and 50 mm, following findings were obtained; in hanging ratio of 0.4,
rigged nets are 18.65 cm, 20.72 cm, 22.80 cm and 25.90 cm, respectively; in hanging ratio of 0.5, rigged nets are 17.90 cm,
19.89 cm, 21.88 cm and 24.86 cm, respectively; in hanging ratio of 0.6, rigged nets are 16.98 cm, 18.87 cm, 20.75 cm and
23.58 cm, respectively. Model lengths of bogue nets that were used in field studies are quite higher than the first reproduction
length. The results show that the nets used in research have no pressure on bogue stock. It was determined that the hanging
ratio may affects the selectivity with the help of other factors. It is taken into account the hanging ratio together with the other
factors affect the selectivity.
Keywords :
SELECT, Hanging ratio, Canakkale, Gillnet, Selectivity, Bogue