P^] THE FISHERIES OF SWEDEN. 391 



The prepnrino. of useful fishery statistics is connected with consider- 

 able trouble and expense, which might justly be considered as too ore^t 

 il the question wa^merely to learn how many tish were caught mid the 

 economical significance of such numbers • but fishery statistics are also 

 from another point of view, of the greatest importance for the fishin- 

 industry. Like any other industry, the fisheries, if thev are to be man" 

 aged m a rational manner, must rest on a scientific basis The first 

 questions which have to be answered are the following : What circiim 

 stances determine the changes in the result of the fisheries ? And which 

 among these are caused by man, and which not ? For this purpose it is 

 m the first place necessary to know the yield of the fisheries, for with- 

 out a knowledge of the fisheries and their yield it is impossible to draw 

 any certain conclusions relative to the circumstances which influence 

 the fisheries. Any one who is earnestly determined to answer the above 

 questions will soon find that the statements of old fishermen cannot 

 be relied upon, as has hitherto been the case in many instances As 

 soon as the question becomes one of science, one can no longer content 

 himself with statements of fishermen, such as that the fisheries o-row 

 worse from year to year, or that such and such a wind brings good^fish- 

 eries &c. Observations are necessary, observations taken systematic- 

 ally for a considerable length of time and taken in different ^localities- 

 in short, the course of the fisheries must be made the subject of scientific 

 investigations. 1 shall below give an instance to show how easy it is 

 to draw hasty conclusions from a knowledge of fisheries limited to a 

 tew years. The importance of investigating the fisheries themselves has 

 ID my opinion, always been too much overlooked, while we are often 

 to d of the vast importance of the investigation of various circumstances 

 which have an influence on the fisheries, such as the flora and fauna of 

 the water, its saltness, temperature, &c. Such investigations are doubt- 

 less important, but only by combining them with data relative to the 

 fisheries themselves do they become of practical value, as otherwise 

 they easily lead to erroneous hypotheses of doubtful value, instances of 

 which are b.it too frequent in th^ history of thefisheries. A knowledo-e 

 VlTT ''.l'''\^f''^'' f«r «"y considerable period of time cannot 

 be obtained without statistical data, and this goes to show that statis- 

 tic^ are the true basis of a thorough investigation of the fisheries 



iMshery statistics are of considerable value, even if thev relate onlv 

 to a certain fishery or a single locality, as showing the cour^^. of the fish- 

 eries; especially if they are accompanied by data relative to variTs 

 circumstances which have exercised an influence on the fisheries. The 



ZZ VuT 'f • r'?f " ''" ''^'''''''' ""'^^ ^^'^ ^''^''' -^^1 »^« their 

 rrnT-hi 1 «"tside of the interest which fishery statistics possess, as 

 furuKshmg the material for a scientific solution of the various problems 



owneis of fishing waters, for judging whether the quantitv of fish will 

 be influenced by the extent to which fishing is carried on,Vor calculat- 



