xvi 



Fourth Annual Report of the 



Hatching of 

 Herring in 

 Deep Water. 



Loch Fyne 



Herring 



Fishing. 



Food of Loch 

 Fyne Herring. 



The results of the imformation gained, as to the food of the 

 herring in Loch Fyne during the summer and autumn, are incor- 

 porated in a paper referred to below. 



Loch Fyne afforded an opportunity during the autumn for con- 

 ducting an experiment as to whether herring ova are capable of 

 developing in deep water. During recent years the great summer 

 herring fishing has been prosecuted further and further from shore, 

 and the average size of the fish captured has diminished so greatly 

 that while in 1860 only, in round numbers, 170 of the 193,000 

 barrels branded were maties, there were 313,000 barrels of maties 

 and only 220,000 barrels of full herrings branded in 1885. Some 

 are inclined to believe the herring shoals are prevented from 

 reaching the inshore spawning banks by the thousands of drift-nets, 

 while others allege that herring eggs are incapable of developing 

 in deep water, i.e., on banks from 50 to 80 fathoms beneath the 

 surface. 



Professor Ewart, when on board H.M.S. 'Jackal,' attempted to 

 ascertain whether spawn was deposited on the offshore banks by 

 dredging. He was, however, unsuccessful, and instead of con- 

 tinuing the dredging in 1884 he deposited artificially fertilised eggs 

 in deep water (104 fathoms) off Fraserburgh. Having failed in 

 the Moray Firth, he next made arrangements for depositing eggs 

 in a heavy slate tank in Loch Fyne during the summer of 1885. 

 From this experiment (see Appendix, page 43), which was entirely 

 successful, it was found that the only difference between the 

 hatching of herring ova in deep and shallow water is one of time. 

 The eggs deposited on deep offshore banks will hatch some days 

 later than those deposited on shallow inshore banks. If the herring 

 which formerly spawned on the inshore banks of the Moray Firth 

 in from 10 to 20 fathoms now spawn offshore in from 40 to 60 

 fathoms water, hatching will be delayed for several days, and 

 maturity will not be reached as early as formerly. This may 

 be deemed an argument in favour of beginning the herring fishing 

 later, instead of earlier, than in former years. 



During the summer and autumn, the migration, rate of growth, 

 and time of spawning of the Loch Fyne herring were studied as far as 

 practicable. These and other questions are referred to in a paper 

 by Mr Brook (Appendix 47). It seems many of the Loch Fyne 

 fishermen believe that the herring migrate backwards and forwards 

 between Loch Fyne and Ballantrae, leaving Loch Fyne in the autumn, 

 to return again in the spring. During 1885 the herring are said to 

 have reached Loch Fyne earlier than usual, and to have, to a great 

 extent, left in August and September instead of October and 

 November. 



On reaching Loch Fyne the herring are chiefly in a spent condition, 

 but they rapidly improve by feeding extensively on the immense 

 shoals of copepods found in the surface waters. 



The most important species of copepod is Calanus finmarcMcus^ 

 which, during the summer, is charged with rich oil globules, that 

 render this species particularly nourishing as food. The superior 

 quality of the Loch Fyne herring is probably due to the richness of 

 the copepods on which they feed. Many of the herring increase 

 considerably in length during the months of May, June, and July, 



