bottom and other factors are variable, but average in no con- 

 spicuous way as any more or less favorable than those of other 

 continents taken as a whole. The character and diversity of 

 our marine life is adequate for conversion of these physical 

 attributes into "fish-flesh." Thus, there is no biological rea- 

 son why production along our coasts should not be roughly 

 equal to that of comparable stretches of coastline in other con- 

 tinents. Ignoring all unproductive polar regions, our coast- 

 lines are about 20% of the world's total. Marine production 

 from regions of our coast is about 9% of the world's total. 

 Evidently, the gross potential for kinds of fish which can be 

 used by man today is at least twice what is now caught off 

 our shores. With this doubling, the catch would still be only 

 at the average world rate, and much greater catches are pos- 

 sible with an intensification to the higher rates of utilization 

 in the more developed fisheries of the world. The North 

 American coastal fisheries are apparently amongst the "devel- 

 oping fisheries" of the world. 



Where is this potential? What is not now being caught 

 that could be turned to as a basis for immediate increases in 

 catch off our shores? Several recent publications summarize 

 potentials region by region, and this is perhaps not the time and 

 place to summarize the local statistics. Of real interest are 

 the trends which seem to be suggested around all shores of the 

 continent. 



First, the offshore fisheries for demersal species are capable 

 of greatly increased production. On both Atlantic and Pacific 

 coasts various species of groundfish are currently being exploited 

 in quantity for the first time — and as we all know, largely by 

 other countries. For example, in the ICNAF area, the North- 

 west Atlantic, there was a catch in 1963 of 2.8 million tons, of 

 which only about one million was taken by Canada and the 

 United States. There seems every prospect that the annual 

 catch from the area can be further increased by harder fishing 

 of the species now taken and by further diversification into 

 species not now utilized ( Martin, 1963 ) . 



A similar demonstration of North American groundfish po- 

 tentials is available on the Pacific coast. In 1961, the catch 

 of groundfish in the Bering Sea by the USSR and Japan ap- 

 proximated 850,000 tons, and included just about one-half of 

 the world's catch of flatfish for that year. By contrast, Ca- 

 nadian and United States production from the Bering Sea 

 grounds was confined to the harvest of less than 3,000 tons of 

 halibut. In recent years, also, the Bering Sea and the Gulf 

 of Alaska have produced substantial quantities of ocean perch, 

 enough to account for from 10 to 30% of the world production 

 of redfish ( rockfish ) . This catch in the past year was made 

 perhaps nine-tenths by countries other than Canada and the 

 United States. And, as in the case of the Atlantic fisheries, 

 there seem many more opportunities for expanding catches of 

 these and other species of groundfish. 



Second, the pelagic and midwater fisheries seem capable of 

 much greater expansion off North American shores. Although 

 herring and their relatives already account for 30% of North 

 American production, their catch could be greatly increased 

 off almost all of our coasts. The anchovies of California, 

 threadfins in the Gulf of Mexico, the herrings of Alaska and 



the herring, capelin, argentine and sandlance of the Canadian 

 east coast have all been mentioned recently as attractive oppor- 

 tunities. Similarly there appear to be large quantities of hake 

 on both east and west coasts that await exploitation, particu- 

 larly perhaps by midwater trawls. 



Third, there are many opportunities for increased catches 

 of crustaceans, molluscs and other bottom-dwelling inverte- 

 brates. Many shrimp and mollusc potentials remain unex- 

 ploited, and a great variety of species which are used in some 

 parts of the world are still untouched along most of our shores. 



Fourth, as the overall rate of fishing intensifies, the rate of 

 catch of some of the favored species declines, and their aver- 

 age size also declines. With progressively smaller catches of 

 smaller-sized fish, the economic return diminishes, even though 

 biologically the species may be capable of supporting an even 

 greater maximum sustained yield. As fisheries biologists have 

 begun to realize, considerations of maximum sustained yield 

 decide how much can be caught, but considerations of maxi- 

 mum economic yield decide how much is caught, and who 

 catches it. In consequence of the competition, some fishermen 

 (perhaps largely from some countries) drop out of the race, 

 and turn instead to other species for which a market can be 

 created. Potential can thus be measured only within the con- 

 text of international competition. Whoever is most efficient 

 has the greatest potential. 



The diversification of catch which arises from competition 

 also carries in its train a number of biological consequences. 

 The ocean is the world's oldest and most complex community 

 of animals. A complex web of interrelationships relates each 

 species, in one way or another, to almost every other species. 

 It is as though, instead of selecting only one species of tree to 

 harvest in the forest, we had begun to take some of each kind. 



What this may do to the ultimate proportions of the various 

 species is difficult to assess. Our ignorance is best illustrated 

 by pointing out that at present we have no generally accepted 

 theory for the effects of fishing on any given pair of species that 

 may be related as predator and prey, or as competitors. Bear- 

 ing in mind that as many as several hundred species may be in- 

 volved in such interrelations, we are on the threshold of some 

 exciting new experiments in marine science as our fisheries 

 develop. 



From the viewpoint of potentials, it would seem likely that 

 we should expect increases in total production but not neces- 

 sarily from the species we have traditionally fished or are now 

 fishing. 



It would seem then from this brief appraisal that our offshore 

 fisheries are capable of substantial expansion. A decade ago 

 we might have been in doubt about some of these potentials. 

 Today they are largely being demonstrated for us by others 

 who, either fishing off our coasts or by their example off their 

 own shores, are pioneering intensive cropping of a great di- 

 versity of marine animals. It is worth saying again — when it 

 come to offshore fisheries, we of North America are amongst 

 the "developing countries". 



Our freshwater fisheries potential is very great compared to 

 other continents, for with the Great Lakes and the large Ca- 

 nadian northern lakes we, together, own the biggest expanses of 



