PROGRESS m BIOLOGICAL INQUIRIES, 19 3 571 



observations of age composition of the catch is the virtually complete 

 absence of yearling squeteague in all three seasons, although fish 

 a year younger and a year older are present. Not only are yearlings 

 absent from the commercial catch, but they also are absent from the 

 catches made by experimental trawls, seines, and hand lines in the 

 bavs where juveniles in their first summer are readily taken. 



Study of published and specially collected statistics of yield indi- 

 cate that fluctuations in central aiid southern New Jersey have been 

 moderate and that squeteague are little, if any, less abundant than 

 during the early years of the fishery. In New York and northern 

 New Jersey, however, remarkable fluctuations, similar to those re- 

 corded from southern New England, were noted. In these localities, 

 a spectacular increase in yield occurred in 1902. The increase per- 

 sisted through 1908, but since that year the catch has fluctuated mod- 

 erately about a level even lower than that which obtained before the 

 increase. 



It was expected that discovery of the causes of the minor fluctua- 

 tion in recent years would cast light on the probable causes of larger 

 changes in the past. This expectation has not been realized, for it 

 appears that fluctuations during the course of the investigations are 

 due largely to marked variation in the numbers of 2-year-old sque- 

 teague entering the fishery for the first time. Thus the general 

 increase in yield of squeteague in New York in 1929 over that of 1928 

 was due almost entirely to the appearance of large numbers of sque- 

 teague of the 1927 year class. This year class continued to dominate 

 the catch in 1930. 



Seasonal distribution of the large catches between 1902 and 1908 

 was so markedly different from that of recent years as to suggest that 

 quite different causes were concerned. Virtually all of the 2-year- 

 oild fish have appeared in the spring during the three years of scien- 

 tific observation, while the few large fish taken have appeared during 

 the summer and autumn. During the period of very large catches, 

 the bulk of the catch was taken in the summer and autumn, the spring 

 ( atches being actually less than those of recent years. This suggests 

 that the large catches between- 1902 and 1908 consisted of large fish 

 and that their appearance was not heralded by unusually large 

 catches of 2-year-old squeteague a few years prior to the period of 

 abundance. This suggestion is confirmed by the testimony Oif living 

 witnesses. 



These facts suggest the hypothesis that migration, either from other 

 coastal waters, or from an offshore reserve, is an important cause of 

 such remarkable increases in abundance as those which occurred in 

 New York and southern New England 30 years ago. Otherwise, it 

 is scarcely credible that such extraordinary numbers of large fish, 

 described as averaging from 3 to 5 pounds in weight, could have 

 appeared without giving notice of their existence by marked increases 

 in spring catches during the years immediately preceding their ap- 

 pearance as large summer fish. 



The principal objective of further investigation will be the testing 

 of the two hypotheses offered in explanation of these peculiarities 

 of behavior on the part of the squeteague. These hypotheses are: 

 (1) Stocks of squeteague north of Delaware represent one or more 

 self-perpetuating units of population, in which successful local repro- 



