SECRETS OF NORTH SEA

Ashburton Guardian, Volume 69, Issue 75, 8 January 1949, Page 5

SECRETS OF NORTH SEA

Investigation by Fishing Experts WHERE DOES WATER COME FROM, AND WHEN? (From Charles Croot.—Reuter’s Correspondent). (By Airmail) . COPENHAGEN. Large-scale and detailed plans have been drawn* up here for a thorough exploration of the North Sea, in the hope of discovering the answer to questions which are puzzling Europe’s fishing fleets. Some of the qustions which experts of six nations will pool their knowledge to answer are: 1. Why do certain varieties of fish suddenly disappear from areas in which they have been found for years? 2. How much of the water in the North Sea comes from where —and when does it come? 3. Why did large numbers of sole die in the Dogger Bank last year? 4. Are fish in the North Sea changing their feeding grounds?

The answers to these and other questions are of more than academic interest to a handful of scientists.

The Iceland fishing industry, for example, has lost some £5,000,000 over the past two years because herring have been driven from the vicinity of the Icelandic coasts by streams of icy water from melting Greenland glaciers. Icelandic fishers want to know where those herring have gone. The plans for the survey were drawn up at a recent meeting here of the International Survey Council for the exploration of the North Sea. For the purposes of this survey, the North Sea has been divided into six areas. Each area will be examined carefully by the appropriate one of the six participants in : the survey—England, Scotland, Norway, Sweden, Denmark and Holland. The w T ork will be carried out by the fishery research vessels of the six nations, by lightships and some of the weather ships stationed in the Atlantic.

Differences in Properties

A survey of the North Sea, according to the experts, must start in the Atlantic, the Southern Arctic, and the Baltic. Water from each of these areas flows into'the North Sea and each has very different properties. Some is warm And some is cold; some is salt and some is only slightly salt. An accurate survey of the precise nature of the various waters entering the North Sea would, it was stated, provide a clue from which it may prove possiblefto deduce the possible movement of the huge North Sea fishing grounds. Temperatures of water all over the North Sea will be recorded at various depths and samples of water will be taken at regular and close intervals. These samples will be examined for oxygen, salt and other chemical content. It is upon this content that depends the growth of marine plants on which fish feed. Professor H. W. Ahlmann, wellknown Swedish glaciologist, who first discovered that the ice and glaciers of Northern Scandinavia and the Arctic were melting and retreating toward the Pole, was one of the scientist® who addressed the International Council. He said there had been climatic changes t'hich had brought to Denmark 25 species of bird which had never been known so far north before. In Greenland, he said, increased temperatures had become particularly noticeable. This has caused certain mammals, such as the seal—.the Eskimo’s main food supply—to retire to colder districts further north. Of interest to the fishing industries was the fact that higher sea temperatures had resulted in enormous catches of cod off Greenland. . He added that cold streams from the melting Greenland glaciers, similar to those which had driven herring from Icelandic waters, were threatening the cod fishery along the Norwegian coast. It is hoped that when the International Council meets in Edinburgh in October, 1949, the countries taking part in the survey will have some interesting reports to make. In addition to the North Sea survey, reports are expected from . a sub-committee- which is examining the comparative efficiency of various types of gear. Swedish and Norwegian experts are experimenting with underwater photography to discover what fish do in the vicinity of nets and other fishing gear.