the size of fish that will be retained by the net, since the smaller, immature fish readily escape through the meshes. Of recent years the various fishery boards, with a view to preventing the catching of such small, immature fish, have increased the size of mesh that is to be used—particularly when trawling within the three mile limit, where the greatest proportion of immature fish is generally encountered. For steam trawlers working in deep water a 2-1/2 in. mesh is generally used, but within the three mile limit it is frequently increased from 3 to 3-1/2 ins. [Illustration: FIG. 18 THE CATCH ABOARD] Herring are caught with drift nets at night near the surface. In the daytime they frequent the sea bottom and can then be caught with a trawl net. Trawling for herrings was first practised by the fishermen of Milford Haven and Fleetwood in 1901. They used an ordinary otter trawl lined with a piece of herring net. A specially constructed herring trawl is now used, of which the cod end is made of 2-1/2 in. mesh instead of the usual 3-1/2 in. When trawling for herrings the steamer goes at full speed, generally for two to four hours, unless a shoal is encountered, when half-an-hour is frequently sufficient. Herrings are trawled in from 70 to 100 fathoms of water over a soft bottom. The main centre for trawled herrings is North-West of Ireland, other fisheries being carried on off the South-West of Ireland, the West of Scotland, and in the North Sea. In 1913 over 500,000 cwts. of herrings were taken with trawl nets in these areas. This method of catching herrings aroused serious opposition among the drift net fishermen. They asserted that the trawl catches and destroys a high proportion of immature fish, and also destroys the herring eggs as it passes along the sea bottom. In 1913 the matter was investigated by a Parliamentary Committee, but any Government action was checked by the outbreak of war. Since 1905 the trawling grounds frequented by British steam trawlers have been divided for statistical purposes into eighteen fishing areas. The names and areas of these regions are shown in the chart of the trawling grounds (Fig. 19). Table I shows in hundredweights the average catch per day’s absence from port in different areas. [Illustration: FIG. 19 CHART SHOWING TRAWLING GROUNDS Frequented by British Trawlers, the “Regions” into which they are divided for statistical purposes, and the approximate area of each in square miles (Nautical) calculated from the 3 mile limit to the 200 metre line. NO. OF REGION. NAME. APPROX. AREA IN SQ. MLS. NAUTICAL I. White Sea 128,917 II. Coast of Norway 29,648 III. Baltic Sea 134,891 IV. North Sea 129,804* V. North of Scotland 18,096 (Orkney and Shetland) VI. Westward of Scotland 32,099