34f> — 



SECTION III 



Importance of the present investigations for the eel fisheries in the Baltic 



countries and Denmark' 



In various ways the investigations described liere are of importance for understanding 

 the practical eel-fisheries, particularly of Denmark and the Baltic countries. 



It holds generally as a main rule for a fishery that we should seek to so regulate 

 its extent, that sufficient young fish may constantly be produced in order that 

 the stock may be maintained properly. This rule holds for all those fishes, which remain 

 in essentially the same waters, during their whole life. For the eel-fisheries in Denmark 

 and the Baltic countries the condition is different. We have seen that the stock of eels 

 here is dependent entirely on the young which migrate in from the Atlantic Ocean. Let 

 us now imagine certain circumstances, which certainly cannot be realized, but may be 

 imagined for the sake of making the matter clear. 



Suppose we close up the English Channel and the passage into the North Sea north 

 of the British Isles in the winter and spring with a fine net, which will not allow the tiny 

 eel fry to pass. What would the result be? Clearly, that after not many years both the 

 Baltic and the North Sea countries would be without eels, as the supply of young fish 

 would be stopped. And it would not make the slightest difference, if, simultaneously 

 with the closing of the passages and meaning to save the stock, we fished fewer eels 

 than usual, perhaps none at all, or if we on the other hand every year fished up all the 

 silver eels (if this could be done). In both cases the result would be, that silver eels would 

 be taken from the closed waters in the first few years as usual in the autumn, that is, 

 so long as the yellow eels present were growing up to silvereels; but after this had 

 happened, there would not be a single eel left in the North Sea and Baltic 

 countries. 



From this we see that the North Sea and Baltic countries are entirely dependent on 

 the supply of eel fry from the Atlantic Ocean. Even though we protect our eels 

 here ever so much, this would not be of any use if the conditions for the 

 supply of young fish from the Atlantic Ocean are unfavourable. We have 

 already seen, how millions upon millions of tiny eel fry begin out here in the autumn to 

 mowe in towards the coasts of West Europe in order to reach the goal necessary for 

 their future development, namely, the fresh water or the shallow coastal waters. Further 

 we have seen, that it depends on many chances, namely, the direction and strenghts of 

 the currents and winds during the period of immigration, how many eel fry will gain a 

 foothold along the coasts that lie nearest the breeding places. It thus depends on 

 these chances, which vary from one year to another, how many young 

 eels are brought to the North Sea and Baltic countries in any particular 

 year. 



It is clear, that of the silver eels which come from the coasts of France and Great 

 Britain, a larger number have the chance of being able to propagate, than of those which 



i) While working up this section I have received very precious assistance from different antherities, 

 especially from Fiskerikonsulent Mag. Sc. Chr. Levinsen. 



