Preliminary Tests of a Shrimp-fish Separator Section for Use in Shrimp Trawls

A prototype shrimp-fish separator to be installed between the body\nand codend of a shrimp trawl was designed and constructed. The\nseparator uses large square meshes to provide an escape path for fish,\nwhile funnels constructed of small mesh webbing keep the shrimp away\nfrom the big meshes and act as leading panels to guide the fish out of\nthe trawl. A prototype was installed in the cut away after parts of a\nshrimp trawl, which was then mounted on an oval steel frame and towed\njust below the surface so that necessary adjustments could be identified\nand tested. After a satisfactory design had been developed, fishing\ntrials were carried out in May, 1984, and further modifications to\nimprove the separating efficiency were made. Preliminary analysis of\nthis data shows that up to 61% of haddock less than 39 cm escaped, and\nup to 30% of cod less than 42 cm. Visual observations of a similar\nseparating section were carried out with a remotely controlled\nunderwater TV vehicle, and these are described.