174 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. 



Ill speaking- of the influence of the wind, it has akeady been said, that 

 when it blows towards the coast and consequently produces high water 

 it is favorable to the fisheries, •whilst when it blows from the coast and 

 produces low water it is unfavorable. Very high water, however, is, 

 according to Gisler, not favorable to fishing on the coast of Korrland. 

 On the coast of Bohusliin it is considered a general rule that steady and 

 tiue weather and high water are best for the fisheries. Very high water 

 is, with us, only caused by violent winds blowing from the sea, which, of 

 course, often interrui)t the fisheries. G. C. Cederstrom says that the 

 herrings are more lively when the water is moderately high than when it 

 is very high. 



22. Of all the hj^drological causes, the currents of the sea doubtless 

 exercise the most important influence on the mode of life and the migra- 

 tions of the herring. This influence seems chiefly to depend on the 

 herring-food which these currents carry, through the temperature and 

 the nature of their water, and through the aid which they render to the 

 migrations of the herrings. 



That the currents influence the herrings in the choice of their spawn- 

 ing-places is chiefly caused by their influence on the temperature of the 

 water and their carrying the necessary food for the young herrings. 

 According to JEclcstrom, it is also quite probable that the herrings in 

 moving to a distant spawning-place take advantage of the ease with 

 which the currents carry them towards their destination. This opinion 

 seems to be corroborated by the place where and the direction in which 

 those herrings which spawn in autumn came to the coast of Bohusliin 

 during the last great herring-fisheries. On the coiu-se of the spawning 

 herring during the spawning-season the current seems, as Boecic already 

 has said, to have but little influence, as the hemngs go to their spawn- 

 ing-places both ^vith and against the current. This does not coincide, 

 however, with the views of other naturalists, according to whom the 

 herrings always go against the current. As land-wind was during our 

 last herring-fishing period considered favorable as long as those herrings 

 which spawn in autumn came to the coast to spawn, and as most of their 

 spawning-places were on the southern coast, it seems that the herrings 

 generally went against the current. The circumstance that fishing 

 for spawning herrings near South Hisingen, at the mouth of the Gota 

 Eiver, is best when laud-wind prevails is explained by the fishermen in 

 this way : that the land-wind accelerates the current of fresh water which 

 is going out and increases the intensity of the under-current of salt water 

 Avith which the herrings are supposed to come in. 



With those herrings which come to the coast for the purpose of seek- 

 ing food, all this is diflerent; for they are chiefly influenced by the occur- 

 rence of this food, which is again dependent on the current.'^'' Thus 



*' Oue must be careful not to draw too rasii a conclusion that spa-vniiug herrings will 

 soon come to a coast in great quantities because many herrings come to that coast to 

 seek food. 



