APPENDIX W _ 14 _ 



Where such catches were ohtaimahle in great quantities, it has been possible to go a step 

 further and obtain from a close study of a large number of catches (journals) an idea of a 

 number of other catches, that is, a representative statistic to a certain extent. 



In this way, the appearance of the fishes at different periods of the year has been ascer- 

 tained; and without actually fulfilling the requirements of a true statistic, namely, that it 

 should give information over the total quantities, this method has yet learnt us which 

 species form the main contributions of the various fisheries (trawl-, long-, line-, snurrevaad- or 

 driftnet-fishery). In the countries where the true statistic is only slightly represented, the 

 representative statistic has naturally had the greatest importance. 



Nevertheless, it is not possible to remain at this stage; in as much as we should like to 

 follow the life of a fish, so to speak from birth to death, it has constantly happened that the 

 data obtainable from the practical fisheries fails in some point or other. Either for example, 

 the quite young stages of the species concerned are not brought in at all by the fishermen, 

 or the species is not taken at certain periods of the year and in such assortments that the 

 required information is forthcoming; consequently, special investigations with profes- 

 sional apparatus had to be undertaken. 



The great expeditions which have been fitted out within recent years for the purpose of 

 investigating the animal-life in the sea — especially at great depths — have been restricted 

 mainly to the use of fishing apparatus wliich had only the width of a few meters (dredge). 

 In the international investigations however, with, it is true, a somewhat different program, stronger 

 fishing apparatus chosen from that which fishes the most and best, has been employed in all 

 lands; the modern ottertrawl especially, has proved to possess an extraordinary importance for 

 these investigations. In the shallower parts of the sea, to a depth of ca. 200 m, it has been 

 possible to use directly the ordinary ottertrawl with a stretch of ca. 30 m. in the ordinary 

 manner of the fishermen. The principal change made, has been to surround the narrow end 

 with a sack of smaller mesh in order to gain possession of the smaller fishes also; in addition, 

 many other attempts have been made, e. g. in Scotland, to study and to improve the fishing- 

 capacity of this apparatus. In the deeper seas, especially near Norway and Iceland, it has 

 been necessary nevertheless to emploj' the ottertrawl in much deeper water, at a depth of 

 some thousands of meters, and a change was thus necessitated in the use of the ordinary 

 fishing apparatus. The change consisted chiefly in this, that only one line was used in towing 

 the trawl and that the two otterboards were connected by means of a crowfoot, so that both 

 could come on board at one place, i. e. over one gallows (see Dansk Biologisk Stations 

 Beretning, VIII). This modification of the apparatus has everywhere proved itself of prac- 

 tical use during the international investigations of late years, at Iceland and Norway. 



The investigations have also been obliged to employ other apparatus. Thus, long-lines 

 have been much used, both lines lying along the ground and lüies floating in the upper 

 water-layers. Seines for fishing on the coasts have also done good service, complementary to 

 the trawl-fishery, for the investigation of the young of the flatfish and gadoids. Drift-nets, 

 especially for herring, have been much used, especially from Norway; it is easily seen however, 

 that the investigation of a mass of water perhaps 100 times deeper than the driftnet is either 

 very imperfect or very protracted; we are lacking here an investigating apparatus for the 

 capture of fishes and other larger animals, e. g. inkfish, which live up in the water, an appa- 



