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Area surveyed includes the Humber estuary. In 1973 and 1979, the east coast was sampled thoroughly. The 1974 sampling only included the south coast. From 1981-1995, both east and south coasts were sampled annualy during September. Data provided are the mean catch during the period. Two types of fishing gears were used during the survey (2m beam trawl and 1.5m push net), both used fine mesh nets with codend liner of 4 mm knotless mesh, a light chain footrope and three tickler chains stretched loosely between shoes. The push net was operated in areas between 0-1m depth while the beam trawl was deployed from a small boat in water up to 20m deep, moving at approximately 1 knot or 35 min per minute. |