December 30, 1909] 



NA TURE 



249 



While in Wales generally hiring fairs are held in 

 ]Mav and November, in districts like South Pem- 

 broke, known to have been occupied by Scandinavians, 

 the hiring fairs are in April and October, and they 

 represent an old equinoctial division of the year. 



John Griffith. 



MARINE INVESTIGATIONS IN NORWAY.' 



THE work done by the Norwegians takes a fore- 

 most place amongst the fishery and marine 

 investigations whicli have been carried out in recent 

 years under the general guidance of the International 

 Council, which was established in igoi to coordinate 

 the researches of the different countries bordering on 

 the North Sea. The present report gives a general 

 review of this work in readable form, without being 

 burdened with any excess of detail, such detail being 

 reserved for special memoirs, some of which are 

 already published. 



The introductory account of the plan and organisa- 

 tion of the work is written by Dr. Johan Hjort, the 

 director of Ihe investigations, and sets forth in the 

 clearest way that effective combination of precise and 

 accurate scientific investigation with practical develop- 

 ments of commercial fisheries which has always 

 specially characterised the work of this investigator. 

 Hydrographical investigation, plankton research, the 

 study of the bottom fauna, each has received its due 

 share of care and attention equally with the study 

 of the natural history of fishes and the experiments 

 which have led to the establishment of new fisheries 

 for cod and for deep-sea prawns off the Norwegian 

 coast. 



In one important respect Norway has been especially 

 fortunate, that is in having had the use of a research 

 steamer, the Michael Sars, designed and built for the 

 particular work of fishery research, an advantage which 

 a parsimonious Government has denied to those who 

 have to carry out similar work in England and Scot- 

 land. A detailed description of this vessel and her 

 special equipment is given by Dr. Hjort, and the 

 efficient and seamanlike way in which she must have 

 been used could not have been better brought out 

 than by the illustration showing the arrangement 

 adopted for working two Petersen young-fish trawls 

 and five tow-nets at the same time, and each at a 

 different water-level. Equally striking are the 

 successful results obtained by working a 50-foot otter 

 trawl at depths of from 400 to nearly 700 fathoms. 



The section of the review dealing with hydro- 

 graphical investigations, by Dr. B. Helland-Hansen, 

 summarises the results which have been reached by 

 a study of the salinities, temperatures, and currents 

 of the Norwegian Sea. In the concluding para- 

 graphs of the section attention is directed to a series 

 of striking correlations between the hydrographical 

 conditions prevailing in the Norwegian Sea and 

 various climatic, fishery, and other phenomena, which 

 appear to be affected by these conditions. Evidence 

 is given for thinking that the amount of heat which 

 the Gulf Stream conveys into the Norwegian Sea 

 has a controlling influence on the winter climate of 

 Scandinavia. From the amount of warmth in the 

 water, recorded as early as the month of May, the 

 author considers that it should be possible to tell 

 whether the succeeding winter will be warmer or 

 colder than usual. For the years 1902-6, in which 

 the investigations took place, a low temperature in 

 the Gulf Stream in the southern portion of the Nor- 



Report on N. 



of Norwegian Fishery and Ma 

 ■ 1 Fishery and M.ariae 



IS, vol. ii., 1909, 



NO. 2096, VOL. 82] 



wegian Sea in May was followed by an early fishing 

 for cod in Lofoten in the next winter, and vice versa. 

 Other correlations of a similar character are also 

 described. 



In dealing with the plankton investigations. Dr. 

 Damas gives an interesting account of his observa- 

 tions on the distribution of the medusa, Cyanea 

 capillata, which is of considerable importance from its 

 intimate association with the fry of the haddock, 

 whiting, and cod. The fry of these fishes shelter 

 themselves under the disc of the jelly-fishes, and are 

 borne along with the latter in their passive wander- 

 ings. Shoals of these Cyanea have been traced from 

 the shores of Jutland into the Skagerak, and thence 

 along the coast of Norway to the north, carrying the 

 young fish with them. Another medusa, ' CyaH«a 

 lamarcki, which has its home in the temperate 

 Atlantic, occasionally reaches the west coast of 

 Norway, accompanied by the fry of southern gadoid 

 fishes, poor-cod, pout, and pollack. 



But in addition to the more indirect, though not 

 therefore less important or less fruitful, ways of 

 approaching fishery problems, represented by the 

 hydrographical and plankton investigations just men- 

 tioned, the Norwegians have devoted very consider- 

 able attention to the natural history of the fishes 

 themselves. Dr. Damas writes on the distribution of 

 the eggs and young stages of the gadoids, and gives 

 also many results of the greatest significance con- 

 cerning the age and growth of these fishes. By an 

 examination of the scales it is now possible to deter- 

 mine with considerable certainty the age of each 

 individual fish. Many catches of cod and haddock 

 were examined in detail in this way, and the number 

 of fish belonging to each year-group was ascertained. 

 The important fact has been determined that fishes 

 born in certain years largely preponderate in the 

 catches, and the effect of these favourable breeding 

 years can be traced in the catches year after year. 

 Similar results have been obtained by Knut Dahl in 

 the case of the herring. Thus in a sample of spring 

 herring examined in the spring of 1907 the eight- 

 year-old fish were in remarkable abundance. The 

 same year-class, in the autumn of 1907, was the most 

 numerous of all the thirteen year-classes which com- 

 posed the large herring of the coast of Helgeland. 

 In the spring of 1908 several thousand spring herring 

 were examined, and the nine-year-old fish were con- 

 spicuously abundant. In the autumn of iqoS, in a 

 large sample of herring from Kristiansund, it was 

 found that the qj-year-old fish were more numerous 

 than either the preceding or succeeding year-classes. 

 In samples from the North Sea and Skagerak the 

 data appear to indicate that here, also, the same vear- 

 class predominated. It is clear that knowledge of 

 this kind, if regularly and systematically collected, 

 will enable estimates of the yield of the fisheries to be 

 made some years before the fishing actually takes 

 place, a result which cannot but be regarded as a 

 triumph for the scientific method of approaching 

 fishery problems. 



Space has only allowed us to touch upon a few of 

 the more striking features of this report. One would 

 imagine that a perusal of it must convince the most 

 sceptical of the value of the new knowledge which 

 is now being rapidly made available as the result of 

 the labours of the International Council for the Study 

 of the Sea. Unfortunately, in this country the con- 

 tinuation of the work still, to some extent, hangs in 

 the balance, but it is to be hoped that our Govern- 

 ment, representing as it does by far the largest 

 fishery interest of the countries bordering on the 

 North Sea, will be induced to take a broad view of 

 its responsibilities. 



