Selectivity Study of trawl in Chabahar Water by cover codend method

Document Type : Other

Authors

1 Department of Fisheries, Faculty of Fisheries and Environment, Gorgan University of Agricultural Sciences and Natural Resources, Iran

2 Scientific Staff of Institute of Baltic Sea Fisheries, Germany

3 Iranian Fisheries Organization, Tehran, Iran

4 Offshore fisheries research center ,Iranian Fisheries Science and Research Institute, Agricultural Research, Education and Promotion Organization, Chabahar, Iran

Abstract

To understand selectivity of trawl, a study was done in fishing ground of Chabahar, Konarak and Pozm by cover cod method in April 2016. 1876 fish including 23 species belonging to 15 families were caught and identified from sampling places among which Cutlassfish (Trichiurus lepturus) with 63% the largest number and Epinephelus areolatus, Torpedo sinuspersici, Epinephelus coioides, Pristipomoides multidens and Netuma thalassina with 0.05 % the lowest number to be included. Catch per unite effort (CPUE) was measured between 161.2 to 637 kg/h but its average measured as 289.98 kg/h.  L50 for Trichiurus lepturus 28.18 cm, for Pomadasys stridens 11.19 cm and for Nemipterus japonicus 12.44 cm measured. Results show T. lepturus caught at the age of maturity. But P. stridens and N. japonicus caught in length much lower than maturity length. In this sense the trawl is not selective and there is a threat to fish stocks in the region.

Keywords

References

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Journal of Animal Environment
Volume 10, Issue 1
April 2018
Pages 263-270

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