An investigation of escapement status of aquatic animals from different parts of trawl nets by pockets in the coastal waters of Chabahar

Abstract

The trawl fishing is used in the waters of the Persian Gulf and the Sea of ​​Oman to catch different kinds of aquatic animals by small and large trawler. One of the most important subjects is the rate and process of aquatic escapement during fishing and standardization of the nets. This research was designed to investigate fish escapement from different parts of the trawl. Sampling was carried out with four small pockets attached in different parts of the net. After six hauling operations, aquatic animals from all of the pockets were identified and measuring. Compare between pockets showed that T. lepturus with mean length of 72.5 cm had the highest value and S. insidiator with 5.2 cm length had the lowest one. In addition, S. tumbil with mean weight of 226 g had highest level while P. semisulcatus with the value of 1.7 g had lowest mean weight. Study of pockets showed highest escapements (64.52%) which was happened in the pocket close to cod end. Comparison between four pockets showed significant difference on amounts of aquatic escapement and the most escapements happened in the pockets close to cod end.