Papers in Marine Biology and Oceanography. Suppl. to vol. J of Dccp-Sca Research, pp 471-471 



New directions in fishery research 



By Lionel A. Walford 



The Fishes of the Gulf of Maine, by Bigelow and Schroi.der, published two years 

 ago, brings up to date a work that has been an American ichthyological classic for 

 30 years. It sums up our knowledge about every species of the northwest Atlantic 

 that regularly occurs in the oceanic bight from Nantucket Shoals and Cape Cod 

 eastward to about 65° W. longitude and including the Bay of Fundy. When read in 

 comparison with the 1924 edition, it measures the progress which biologists have 

 been making in their studies of fishes in this area. In bringing together the work of 

 three generations, it marks where we are now, and serves as a basis on which to 

 consider the question of where to go from here. In the following paragraphs, I propose 

 to examine some facets of this question from the viewpoint of fishery research. 



In general, the ichthyological fauna of the North Atlantic is now fairly well known; 

 at least the species which are of actual or potential commercial interest are well 

 known. This does not mean that taxonomy is finished in the Gulf of Maine (or any- 

 where else for that matter) leaving only the routine job of keeping the bottles on the 

 museum shelves properly labelled and filled with alcohol. What has been done so 

 far is to lay the foundation on which the taxonomy of the future must be built; for 

 there remains the enormously important and difficult work of clarifying conceptions 

 of the sub-populational structure of the species. This is not of '" mere academic 

 interest ", as people who are unsympathetic to this line of research sometimes scorn- 

 fully assert. Fishery investigators have everywhere shown it to be a fundamental 

 necessity; for sub-populations often differ enough from each other in many ways— 

 in rates of growth and mortality, in fecundity, in migratory habits, and in various 

 other biological characteristics, that these segments of species must be studied, fished 

 and regulated as distinct entities. 



No matter how distinct they may be genetically, however, they are exceedingly 

 diflficult to define, for body proportions and meristic counts vary widely within sub- 

 populations; they overlap broadly between populations; and they are affected by 

 the continually varying conditions of the environment, particularly temperature. 

 Because of the consequent hmitations in the usefulness of anatomical features, other 

 means of identifying sub-populations are being sought in the fields of biochemistry, 

 serology, parasitology, and experimental marking. Whatever methods be used for 

 analysing sub-populations, it is necessary to systematically sample large quantities of 

 fish throughout the range of each species under study. In the northwest Atlantic, 

 this laborious and costly work has hardly begun. So far. it has necessarily been 

 concentrated on only the species of greatest commercial importance, namely haddock, 

 cod and red-fish; and even these few species have been studied intensely only over a 

 part of their total distributions. Thus, the study of sub-populations oi these must 

 continue, while that of all the other species still lies ahead. 



The Fishes of the Gulf of Maine is full of information that is best classed as Natural 

 History. There is much more of this than could be assembled for other parts of North 



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