A series of nine fishing trips with on board observers were carried out on MFV UK153 (PT1) and two beam trawlers (BT1, BT2) of comparative engine power and size to appraise the performance of pulse beam v.s. conventional tickler chain beam trawls. The main conclusions from this study are: 1. Landings of plaice and sole are significantly lower in the pulse trawl when compared to the conventional beam trawl. 2. There was no significant difference in the catch rates of undersized (discard) plaice between the pulse trawl and the conventional trawl. 3. In the pulse trawl, the catch rates of undersized (discard) sole were significantly lower than in the conventional beam trawl. 4. The catch rates of benthic fauna (nrs/hr of Astropecten irregularis, Asterias rubens, and Liocarcinus holsatus) were significantly lower in the pulse trawl compared to the conventional beam trawl. 5. There are indications that undersized plaice are damaged to a lesser degree in the pulse trawl and will survive better in the pulse trawl. Based on previous research, these results would indicate a survival rate of plaice in the pulse trawl that is twice as high as in a conventional beam trawl. But since the method of determining damage to fish by visual observation is subjective, this conclusion should be treated with caution.
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