Abstract: The bottom trawls were modified by increase in network back mesh size in the original network of the fifth section of the bottom trawls in order to reduce bycatch and small juvenile fish in the operation of the bottom trawl,and tested 10 times in the waters near the Haiyang Island using alternating operations issued by the original production network.The results showed that there was 69.87 kg of catch weight in the test network,less than that in the original production network,and that 27 species of fish were captured by the original production network. While 19 species were caught in the test network,8 species less than by the original production network,and with less bycatch.Compared to the original production network,the body length of the main catch in the test network was shifted to the right in the body length frequency curve,indicating that the test network released the smaller catches of the fish and protected the larvae resources.The findings provide a reference for the structural optimization of trawl fishing gear and the protection of fishery resources.
2017, Vol. 32 
