- 80 - 



The further we go northwards in the North Sea along the continental coast, the 

 scarcer is Gadus luscus. Thus in Redeke's trawling investigations on the Dutch coast to 

 study the proportion of fish remaining in the -net and the proportion escaping, only 

 1 Gadus luscus was obtained in contrast to 30 Gadus callarias and 1581 Gadus merlan- 

 gus^, and still further to the north it is so rare on the Danish coast, that Dr. A. C. Jo- 

 HANSEN according to information from him has not found a single specimen in his exten- 

 sive hauls with the trawl. From the Danish waters only quite few specimens on the 

 whole of Gadus luscus have been recorded hitherto, so that it is obviously very rare there 

 and this applies also to the Norwegian and Swedish waters (Lilljeborg). At western Nor- 

 way it has not been found at all (R. Collett, Meddelelser om Norges Fiske i Aarene 1884 

 — 1901, II, 1903), which is sufficiently remarkable in itself, since it is not altogether un- 

 common in the Atlantic on the north of Scotland and is even known from the Shetlands. 



It seems therefore as if the pelagic young of this species were not carried in any 

 large numbers very far away from the spawning places (in the Channel and the most 

 southern parts of the North Sea as also the Scottish coasts), as may be the case with 

 other gadoids, and the reason for this in my opinion is to be found in the fact that the 

 species is so distinctly a shallow water (coastal) form, whose pelagic life likewise seems to 

 be only of short duration. 



Whilst Gadus luscus is extremely rare so far to the north as the Danish and Swe- 

 dish waters, it is said to be fairly common at Heligoland according to Heincke and Ehren- 

 BADM (1. c), but how far it reproduces there cannot as yet be said to be determined. Ac- 

 cording to friendly information from Prof. Ehrenbaüm the fry of this species are in any 

 case not common at Heligoland, where the pelagic stages have not been found. On the 

 other hand Prof. Ehrenbaüm once took 12 Gadus luscus young of 3—9 cm. in length in 

 13 meters depth at the mouth of Oster Ems on June 15th, but he does not believe that 

 these were spawned at that place or in its neighbourhood, but that they came from 

 further to the west. 



As the main result of the above considerations it may be said, that Gadus luscus 

 reproduces at most extremely little in the North Sea with exception perhaps of the most 

 southerly part. It may not be considered as excluded also , that the greater part of the 

 young specimens which are found fairly commonly in the southern and south-eastern 

 parts of the North Sea have been carried there as pelagic fry. Since the species is so 

 distinctly a coastal form, it is not surprising that we have not found its young on our 

 lines across the North Sea, but that this has not been the case at our stations in the 

 neighbourhood of the English and Scottish coasts seems to show that there also extremely 

 few young at most are produced^. 



' Bedeke, Ueber einige Versuche mit Netzen, Verhandelingen uit het Eijksinstituut voor het onder- 

 zoek der Zee, I, 1906, Tabelle V. 



'^ It is not improbable however that a more intensive investigation of the coastal belt than naturally a 

 foreign vessel like ours could make, will be able to prove the presence of the pelagic fry on those coasts 

 from which ripe specimens of Gadus luscus have been noted by several British authors, most recently by 

 WiLLTAMSON from the neighbourhood of Aberdeen (24th Ann. Report fishery Board for Scotland, 

 p. 130, 1906). 



