— 111 — 
the following record of hauls made with the fine-meshed trawl on board the “Michael 
Sars”. 
Trawl Catches. Percentage of 5 cm. groups. 
Il 1 T 
|| 10— 15-20 125 |30— | 35— | 40— | 45— 50 55 60—|65—|70 
| 14 EIEN 54 | 59 | 64 | 69 | 74 
| Zu ] ie | | a | | 
| | N | 
Bear Island, Aug. 1905....... à 001 (640 136 7 7.2 | 7 A| BO ce Ihe | | 
Cape Kanin Bank, er 1907. | | | Ar 3 | 32.1 | 18.0 8.0 2 jos 04) ne 
Varangerfj., June 1913. = 40 | 3 | 2 | | 8 | 10 | 13 DE | 1/2/12 
| | | | 
During August 1905, the mass of the trawl catches made off Bear Island consisted 
of fish between 15 and 19cm. long. In August 1907, the hauls made in the eastern part 
of the Barents Sea were mainly composed of young cod between 25 and 34 cm. long. 
In 1913 however, we again find a great quantity of quite small fish (10—14 cm.), the 
catches here, however, also including many specimens belonging to the 40—44 cm. group. 
As will be seen later, this difference in the respective composition of the catches can 
scarcely have been accidental, but must rather be considered as due to great fluctua- 
tions in the average size of the stock, and as the older and larger groups recruit from 
these small fish, it is of great importance to note the existence, even at this early stage, 
of fluetuations in the relative frequency of the different sizes. 
Not until they have reached a length of some 40 cm. do the cod begin to be taken 
by the fishermen’s lines, for which reason no information is available as to the younger 
stages save that obtained by scientific investigations. As to their migrations also, little 
is known; no marking experiments have ever been carried out with cod of less than 40 
em. length, either in the Barents Sea or the Finmark waters. Marking experiments with 
young cod have, however, been carried out to a considerable extent elsewhere. 
Marking of small cod. 
Dr. Jous. Scumipt has made marking experiments with a number of young cod in 
the Iceland and Faroe waters. In the former*), two series of experiments resulted in 
the recapture of only 8.4 and 1.6 % of the marked fish, the migrations indicated being 
of small extent. In the latter water however**), where some 4—5,000 cod were marked 
during the years 1909—1912, an extremely large proportion was retaken. Of 800 fish 
marked in 1909, no less than 485, or over 60 %, were recaptured, and this very close 
to the spot where they had been set free. 
In the North Sea, marking experiments with small cod under 40 cm. have been car- 
ried out by the German fishery investigations, especially from Heligoland. Of the fish 
here marked, 76.5 % were recaptured at the places where they were freed. WercoLp, 
in his description***) of the experiments, is of opinion that about half of the fish marked 
were retaken at exactly the same spot. 
*) Marking experiments on Plaice and Cod in Icelandic waters. Meddel. fra Kommissionen for 
Havundersogelser, Kobenhavn 1902. N 
**) Command. C. F. Drechsel: The International Investigation of the Sea, its results and prac- . 
tical objects. Kobenhavn 1912. 
***) Die deutschen Versuche mit gezeichneten Dorschen. 1. Bericht. Arb. der deutschen wiss. 
Kommission für die internationale Meeresforschung 1913. 
