166 REPOET OF COMMISSIONER OF FISH AND FISHERIES. 



can be quickly filled. The oblique direction in wliich the rays of the 

 sun and the moon strike the surface of the water doubtless has a great 

 influence. In many places the fishermen use torches during fishing- 

 firmly convinced that the herrings are at night-time attracted toTvards 

 the surface by light. Valenciennes mentions an observation made by 

 Prench fishermen, "that in -udnter the herrings do not begin to stir 

 until the sun rises, when they come nearer the surface, and that the 

 same also applies to the newly-hatched herrings." 



13. Of all meteorological causes, the temperature of the air seems to exer- 

 cise the most decided influence on the herrings, chiefly through its influ- 

 ence on the weather in general, and more especially on the temperature of 

 the water and the quantity of herring-food. The herring (as we shall 

 show farther on) prefers a certain even temperature, and as this is 

 not found near the surface or near the coast, it goes into deeper water 

 or farther away from the coast. We thus possess numerous data show- 

 ing that both the herring and the small herring have .by cold weather 

 been hindered from approaching the coast, or that the fisheries which 

 had already commenced duiing mild weather have been interrupted 

 from the same cause. During the winter herring-fisheries mild weather 

 is therefore generally considered favorable, although this is certainly 

 not the case under all circumstances. For it is well known from the 

 last great Bohuslan herring-fisheries as well as from the western coast 

 of Scotland, that the remaining of the snow on the mountains and the 

 consequent considerable cold are thought to promise good winter fishing, 

 whilst thawing weather produced by a southeasterly wind is considered 

 unfavorable. Gre*at heat has just as much influence on the fisheries as 

 great cold, and the fisheries which are carried on during the warm sea- 

 son are just as much inconvenienced by the heat as the winter fisheries 

 by the cold. The herrings seem to keep at a certain depth which is 

 regulated by the temperature, so that in moderately mild weather they 

 are nearer the surface, and at a greater depth either in very cold or very 

 warm weather. Miinter relates, that in Pomerania the wicker baskets 

 for catching herrings must be placed deeper, as in spring the warmth of 

 the sun increases ; and it is well known from the large fisheries which 

 during summer and the beginning of autumn are carried on in the north- 

 western portion of the North Sea, that cooler weather brings good fish- 

 ing. After a very hot spring and summer the herrings are also said not 

 to come so near the eastern coast of Scotland as they do otherwise. 

 There it has, however, been noticed that a high temperature at the be- 

 ginning of the fisheries, if immediately followed by a comparatively lower 

 temperature, has been favorable to fishing. It is well known on the 

 Limfiord (Denmark) that a warm summer is generally followed by rich 

 autumn fisheries, so that the saying has become proverbial there, " Many 

 files, many herrings." Both the herring and the small herring are 

 northern fish which like cool but not entirely cold water, and some of 

 our most important fisheries are therefore carried on during the coldest 



