SCIENTIFIC REPORTS. 



I. — TRAWLING INVESTIGATIONS. By Dr. T. Wbmyss Fulton, 

 F.R.S.E., Superintendent of Scientific Investigations. 



Introductory. 



The investigations into the condition of the fishing grounds in certain 

 parts of the closed waters, particularly in the Moray Firth and Aberdeen 

 Bay, which were begun a few years ago by the employment of commercial 

 steam trawlers, were continued last year as frequently as circumstances 

 allowed. Trawlings were made in January, March, April, September, 

 October, November, and December, the total number of recorded hauls 

 in the closed waters amounting to 91, of which 14 were made in Aber- 

 deen Bay, 75 in the Moray Firth, and 2 in Sandside Bay, on the north 

 coast of Scotland. The localities in the Moray Firth which were most 

 thoroughly examined were Burghead Bay and adjoining parts of the 

 south coast, the Dornoch Firth, and the grounds off the coast of Caith- 

 ness. A few hauls were also taken on Smith Bank, and in the deeper 

 parts of the Firth, at the so-called " witch-grounds." 



The aggregate number of fishes taken in the course of these trawlings, 

 so far as they were completely recorded, was 63,525, and of these 44,538 

 were taken to market, the remaining 18,987 being thrown overboard, 

 either because they belonged to species which are not edible, or, more 

 commonly, because they were too small to be marketable. The propor- 

 tions of the marketable and unmarketable in each of the recorded hauls 

 are given in the Tables appended. 



Records were also made of a number of hauls of a steam trawler which 

 fished at the Faroes in the month of May, and these are likewise 

 included in the Tables. 



One of the chief objects of these trawling investigations is to ascertain 

 as far as possible the changes which may occur in the abundance of the 

 food and other fishes in the closed waters in different years and at 

 different seasons, but observations are also made on the reproduc- 

 tion of the fish, their spawning, food, &c, and on various other matters 

 connected with their life-history, while at the same time records 

 are made of the surface and bottom temperatures of the water on the 

 various grounds visited. The employment of commercial vessels for this 

 purpose is associated with certain disadvantages ; but from the fact that 

 the actual trawling work, is carried on precisely as it is when fishing for 

 market purposes, opportunities are afforded for a number of observations 

 bearing on this method of fishing, as, for example, the proportion of the 

 marketable and unmarketable fishes which are captured, the relation 

 between the size of the fishes taken and the size of the meshes of the 

 net, the vitality of the fishes, &c. Collections are also made of the floating 

 organisms, or plankton, and of fish eggs and larvae, and experiments con- 

 ducted with small-meshed nets with the view of procuring collections of 

 fishes of various sizes in connection with the study of their rate of 

 growth, distribution, &c. 

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