THE UTILITY AND METHODS OF MACKEREL PROPAGATION. 



BY J. PERCY MOORE. 



The esteem in which the mackerel is commonly held as a food-fish and the great 

 importance of its pursuit and capture to a large part of the population of certain 

 sections of New England have naturally caused the welfare of the fishery to be jeal- 

 ously guarded. During the past decade the frequent failure of a season's fishing to 

 earn profits has given rise to a fear that the supply is in danger of speedy exhaustion. 

 It was this supposed danger which several years ago led those who have labored in 

 the interests of improved fisheries to experiment with the artificial propagation of 

 the species. It was hoped that the method which had repeopled so many depleted 

 streams and lakes, which not only saved from extinction but extended the shad fish- 

 cries, and which is no doubt destined for still greater triumphs in the future, would 

 be capable of rejuvenating some of our decrepit sea fisheries. Though the evidence 

 is by no means unequivocal, these hopes appear to have had a certain warrant in 

 the cases of two sea fishes, for which suitable apparatus and methods have been 

 devised. It is the purpose of the present sketch to point out what appear to be the 

 possibilities and limitations of the method when applied to the mackerel. 



The subject may be stated as two principal problems, viz: (1) Is the alleged 

 scarcity of the mackerel a sufficient reason for believing that the supply is becoming 

 exhausted? (2) If so, can the supply be increased and maintained by recourse to 

 artificial propagation ? 



A glance at the statistics covering the last twenty years may seem to confirm the 

 gravest fears, for from 350,000 barrels in 1880 and 395,000 barrels in 1881 the catch 

 inspected in Massachusetts fell to 75,000 barrels in 1886 and 18,000 barrels in 1891, 

 since which year there has been some slight increase. Fortunately statistics of the 

 catch covering a long period are available for several of the New England States. 

 The late Dr. Goode has presented, in his " History of the mackerel," a curve showing 

 the number of barrels of salt mackerel inspected in Massachusetts annually from 1804 

 to 1881, and this exhibit has been extended in the annual reports of the Boston Fish 

 Bureau. The frequent and great changes in the course of the curve, corresponding to 

 variations in the number of barrels, are very striking. But a remarkable regularity in 

 the periodicity of the more important fluctuations, is apparent. Thus, great catches 

 were made at intervals of about twenty years, in 1831, 1851, about 1870, and in 1881; 

 the smallest catches alternate with these, namely, in 1814, 1840, 1850, 1877, and 1891. 

 Smaller variations of shorter and less regular duration occur between the larger. 



By eliminating these minor irregularities, the great movements and the general 

 tendency of the fishery become more evident. This elimination is accomplished by 

 averaging the annual figures for overlapping periods of ten successive years, beginning 

 with each year from 1820 to 1882. The curve plotted from these results is much more 

 uniform than that exhibiting the annual inspection ; it rises and falls regularly and 

 gradually at long intervals above and below a line representing the mean annual 



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F. C. B. 1897-23 



