FISHES OF THE GULF OF MAINE 



93 



of fish about Eastport, herring rarely spawn when 

 less than 9% inches long; usually not until they 

 are 10 to 10% inches; and most of the spawners 

 are 12 to 13 inches long. This means that some 

 few spawn when only 3 years old, if the growth 

 schedule outlined above is correct, but most of 

 them not until 4 years or older, to continue 

 spawning annually thereafter as long as they live. 

 In Norwegian waters, too, a few spawn at 3 years, 

 many at 4 years, and the majority at 5 years; some 

 few not until 6 years old. Herring have been seen 

 as old as 20 years, and they may live even longer. 



Success of reproduction. — The relative abund- 

 ance of any species of sea fish from year to year 

 depends less on how many individuals spawn in 

 any locality than it does on how many of the 

 resultant fry survive. And the many age analyses 

 that have been made of herring in European waters 

 have proved that while a very large crop of young 

 may be produced in some years, hardly any are in 

 others, even in favorable nurseries. Apparently 

 this applies more to the northern breeding grounds 

 than to the southern (to some extent, however, to 

 all) the result being that the herring spawned in 

 some one favorable breeding season may dominate 

 the schools over large areas for many years, or 

 until another successful breeding year comes, 

 producing another large crop. In Norwegian 

 waters, for example, the herring produced in 1904 

 was dominant in the catches for the next six years, 

 at least; this is a classic instance. Lea found, 

 similarly, that herring hatched that same year 

 (1904) dominated the catches on the west coast of 

 Newfoundland as long afterwards as 1914 and 

 1915. And while precise information is not avail- 

 able for our Gulf, no doubt the same rule governs 

 there. 



One case, at least, is well documented of a 

 particular body of Bay of Fundy herring that 

 received no important recruitment for something 

 like 10 years, when the few still remaining seem 

 to have disappeared, from old age (p. 99). 



Various explanations have been proposed to 

 account for this, such as abundance or scarcity of 

 microscopic plankton, favorable or unfavorable 

 temperature, salinity, or other factors, all of 

 which may enter in. And while it is during the 

 first few weeks of life that the herring is most 

 vulnerable, it is also possible that the conditions 



under which the parent fish lived for the year 

 preceding spawning may influence the fate of the 

 fry. Whatever the explanation, the fact that 

 such fluctuations do occur from year to year, in 

 the numbers of fry reared is of the greatest 

 practical interest to all concerned with the sea 

 fisheries, as evidence that variations existing in 

 the stock of herring, and consequently in the 

 catch, may be due more to the success or failure 

 of reproduction than to any effect the fishery may 

 have on the stock. 



General range. — Both sides of the North Atlan- 

 tic. Off the European coast the herring ranges 

 north to Norway, Iceland, Spitzbergen, and the 

 White Sea; south to the Straits of Gibraltar. It 

 is known on the American coast as far north as 

 northern Labrador and the west coast of Green- 

 land; regularly and commonly as far south as 

 Cape Cod and Block Island ; and it is occasionally 

 seen in small numbers as far south as Cape Hat- 

 teras in winter. It is replaced by a close ally 

 (C. pallasii) in the North Pacific. 



Occurrence in the Gulf of Maine. — To fist the 

 localities where herring have been recorded would 

 be to mention every hamlet along our coasts 

 whence fishing boats put out, for more or less 

 herring, large or small, appear at one season or 

 another around the entire coast line of the Gulf, 

 and on the offshore fishing banks as well. They 

 also enter bays and estuaries freely, but they have 

 never been reported in our Gulf from water that 

 is appreciably brackish; perhaps 2.8 percent 

 salinity 38 may be set at about their lower limit. 



The distribution of commercial catches, plotted 

 by Needier (fig. 44) 39 shows that herring are far 

 more plentiful from Casco Bay eastward along 

 the coast of Maine, and especially in the Passama- 

 quoddy Bay-Grand Manan region than they are 

 along the western shores of the Gulf on the one 

 hand, or up the Bay of Fundy on the other, or 

 along western Nova Scotia. Thus the landings 

 per unit length of coast averaged 3 times as great 

 for the Passamaquoddy-Grand Manan region 

 and for the coast of Maine to Mount Desert, as 

 for the coast sector from Mount Desert past 

 Penobscot Bay; about 4 times as great as for the 

 Maine coast as a whole, westward and southward 



» Surface, in Bay of Fundy in May. 



" A reliable index, for the herring is a valuable fish. 



